DIYBio meeting notes
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Bugs
Jan 16, 2011, 12:14:50 PM1/16/11
to London Hackspace
This is a brief(ish) summary of what we got up to at the biohacking
meeting last night. Thanks to everyone who came along; i was good fun
and I think we go some useful ideas out of it!
==================
Research Projects:
Food Phylogeny project:
Collecting samples of foodstuff from various sources (different shops,
markets, etc), then extracting DNA and sending it for partial DNA
sequencing. By looking at something like ribosomal RNA sequences [1],
we should be able to build up an idea of e.g. whether all of a certain
fruit from a given company are actually all from cones of the same
plant, how much diversity there is between suppliers, etc. Extracting
the DNA is pretty easy (we need a kit, but they're readily available),
then we need to do a PCR to amplify the gene(s) we decide to sequence,
then pass this amplified DNA on to a sequencing service. We can start
experimenting with DNA collection (I can take small samples into my
lab to assess the DNA we get out for purity), but can't go ahead
properly until we get PCR ingredients [5] access to a thermal cycler.
Microbial survey:
Collecting samples from our environment, then swabbing them onto
various differential growth media [2]. For a given sample, the pattern
of media on which it does or doesn't grow (and how it looks on some
media) will tell us a lot about what bacteria, yeast and fungi were in
that sample. Ideas include: (a) Do we have Legionella sp. in the
space's water tanks? (b) How clean are our fridges, kitchen, etc? (or
cutlery swiped from local restaurants) (c) How does the population of
bacteria living on our skin vary between group members? ...etc. Need
to get some ingredients in for making the media and need to set up an
incubator to grow the bacteria in.
Endogenous retroviruses:
Endogenous retroviruses [3] are cool. This would be a project to take
samples of our own DNA and perform PCRs designed to detect the
presence or absence of specific endogenous retrovirus fragments in our
own DNA. We can see how much we vary in which endogenous retroviruses
we're all carrying. Needs DNA extraction kit, PCR ingredients, a
thermal cycler and a load of thought to design the primers. Also need
to be able to do agarose gel electrophoresis... so something like the
gel box from pearl biotech. [4]
Detecting GMO in foods:
Taking samples of foods from a range of sources, extracting the DNA
and then checking to see whether the foods contain DNA from
genetically modified organisms. Despite strict restrictions on
importing them to the EU, it's surprising where these things crop up.
Sequences that would allow us to design the appropriate PCR primers
are available online. We need DNA extraction, PCR ingredients and
access to a thermal cycler, agarose gel electrophoresis.
Curry Identification Project:
Similar idea to Food Phylogeny and Detecting GMOs - taking samples of
meat from various curry houses, and checking to see whether they're
actually the meat that they claim to be and whether they're
contaminated with any other species. I'm told (although have never
checked) that some years back, pork DNA was found in chicken breasts
sold in a UK supermarket (some pig product was used in the solution
that gets injected into cheap chicken breasts to bulk them up) which,
understandably, irked a load of religious people. So could be an
interesting one! Requirements are probably the same as those for
Detecting GMOs in foods.
Microbial Fuel Cells:
Tim is experienced in experimenting with microbial fuel cells [6].
Briefly, bacteria are encouraged to grow on an electrode in an
environment without oxygen (e.g. in the mud under a pond), where
they're forced to break down their food in a way that involves dumping
electrons into their environment (thus, the bacteria dump electrons
into our electrode). A second electrode is suspended in a body of
water, which can act as a sink for the dumped electrons, and so we can
get a current flowing between the two. If algae are growing in the
water, they can turn sunlight into sugar to be eaten by the generating
bacteria, thus effectively turning the system into a solar cell. Lots
of room for experimentation here: isolating and identifying the most
efficient species/strains of generating bacteria (and fun with
directed evolution to improve this), playing with environmental
conditions (temperature, pH, salinity, light exposure, purity of
culture, etc etc).
We set up a first fuel cell last night, fed with cheese and few salad
leaves as starting biomass. Weird way to set one up so it might not
work, but worth a try until we get some more resources (basically:
mud) together. At the moment it's on the windowsill in the room where
we had our meeting, that used to be the machine shop.
================
Equipment Projects:
Incubator:
We need a warm box (one or two cubic feet will be fine) with a shelf
inside, that we can keep at 37 degrees. Realistically, 35 degrees +/-
3 degrees should be OK. We discussed setting up a system relying on
peltier warmers/coolers with a fan to circulate the air. This would be
great, as we should have good control over temperature and be able to
set e.g. 16 hours at 37 degrees then stay around 4 degrees until
turned off, if we set up a bacterial culture overnight and no-one is
free to come in the next day.
Thermal cycler:
There are several possibilities for thermal cyclers... they turn up on
eBay fairly regularly, or we can build our own. OpenPCR are due to
release their open-source machine, kit, and plans within the next few
months (no set release date, though). Much simpler designs may also be
possible, e.g. with peltier systems or the "lightbulb PCR" system.
These will be cheaper and faster to get hold of, but possibly a lot
more tempermental. They could certainly be a lot of fun to build and
test, though!
Centrifuge:
We'll need a microcentrifugue at some point. We can try printing a new
dremelfuge or getting one machined out of metal (possibly safer
failure characteristics). We're also going to try opening up a "Henry"
vacuum cleaner, as it's already a fairly powerful motor inside a
robust plastic bucket. We need to do some calculations to check the g
forces we could achieve, and we need to keep an eye out for a free or
very cheap Henry.
Vacuum manifold:
Easier and safer alternative to a microcentrifuge for some
applications. Basically a box hooked up to a vacuum source (vacuum
cleaner should be easily good enough), with nozzles on the top to
accommodate a specific fitting common to several molecular biology
kits. Should be an extremely simple build. I'll look into the
measurements for this.
============
Next steps:
A) This information -- along with all that I've forgotten, got wrong
or omitted -- would be useful on the wiki. Maybe a short page for each
project?
B) I will select and find prices for the resources we'll need for the
two least resource-intensive projects: microbiological survey and fuel
cells. I'll put up a wiki page ASAP, followed by a pledge page so we
can get going.
C) Meanwhile, we'll look into building (or buying):
An incubator (should be an easy build, probably the most urgent on
this list)
A thermal cycler (eBay or home-built)
A centrifuge (might take some thought; I'm keen to try printing and
testing a new dremelfugue, when the printer is back in action)
A fridge (ideally with a small freezer compartment)
An electrophoresis tank: plans are available online, so it should just
be finding the materials and laser cutting them?
...Then as these things become available, we can start moving onto the
other cool projects that we've had suggested.
D) Plan another meetup soon. A day where we can build and prototype
some of the equipment, as well as get started on the first experiment.
Wow, that was long!
Thanks again to everyone who came along! Probably most of our meet-ups
in the future will be more practical than talky, unless people are
interested in education sessions?
Have fun,
Bugs
[1]http://en.wikipedia.org/wiki/18S_ribosomal_RNA
[2]http://www.midlandstech.edu/science/kelleherk/225/labmaterials/
sel_diff_media.html
[3]http://en.wikipedia.org/wiki/Endogenous_retrovirus
[4]http://www.pearlbiotech.com/hardware/
[5]http://www.qiagen.com/products/pcr/fastcycling/
qiagenfastcyclingpcrkit.aspx ...or similar
[6]http://www.microbialfuelcell.org/
meeting last night. Thanks to everyone who came along; i was good fun
and I think we go some useful ideas out of it!
==================
Research Projects:
Food Phylogeny project:
Collecting samples of foodstuff from various sources (different shops,
markets, etc), then extracting DNA and sending it for partial DNA
sequencing. By looking at something like ribosomal RNA sequences [1],
we should be able to build up an idea of e.g. whether all of a certain
fruit from a given company are actually all from cones of the same
plant, how much diversity there is between suppliers, etc. Extracting
the DNA is pretty easy (we need a kit, but they're readily available),
then we need to do a PCR to amplify the gene(s) we decide to sequence,
then pass this amplified DNA on to a sequencing service. We can start
experimenting with DNA collection (I can take small samples into my
lab to assess the DNA we get out for purity), but can't go ahead
properly until we get PCR ingredients [5] access to a thermal cycler.
Microbial survey:
Collecting samples from our environment, then swabbing them onto
various differential growth media [2]. For a given sample, the pattern
of media on which it does or doesn't grow (and how it looks on some
media) will tell us a lot about what bacteria, yeast and fungi were in
that sample. Ideas include: (a) Do we have Legionella sp. in the
space's water tanks? (b) How clean are our fridges, kitchen, etc? (or
cutlery swiped from local restaurants) (c) How does the population of
bacteria living on our skin vary between group members? ...etc. Need
to get some ingredients in for making the media and need to set up an
incubator to grow the bacteria in.
Endogenous retroviruses:
Endogenous retroviruses [3] are cool. This would be a project to take
samples of our own DNA and perform PCRs designed to detect the
presence or absence of specific endogenous retrovirus fragments in our
own DNA. We can see how much we vary in which endogenous retroviruses
we're all carrying. Needs DNA extraction kit, PCR ingredients, a
thermal cycler and a load of thought to design the primers. Also need
to be able to do agarose gel electrophoresis... so something like the
gel box from pearl biotech. [4]
Detecting GMO in foods:
Taking samples of foods from a range of sources, extracting the DNA
and then checking to see whether the foods contain DNA from
genetically modified organisms. Despite strict restrictions on
importing them to the EU, it's surprising where these things crop up.
Sequences that would allow us to design the appropriate PCR primers
are available online. We need DNA extraction, PCR ingredients and
access to a thermal cycler, agarose gel electrophoresis.
Curry Identification Project:
Similar idea to Food Phylogeny and Detecting GMOs - taking samples of
meat from various curry houses, and checking to see whether they're
actually the meat that they claim to be and whether they're
contaminated with any other species. I'm told (although have never
checked) that some years back, pork DNA was found in chicken breasts
sold in a UK supermarket (some pig product was used in the solution
that gets injected into cheap chicken breasts to bulk them up) which,
understandably, irked a load of religious people. So could be an
interesting one! Requirements are probably the same as those for
Detecting GMOs in foods.
Microbial Fuel Cells:
Tim is experienced in experimenting with microbial fuel cells [6].
Briefly, bacteria are encouraged to grow on an electrode in an
environment without oxygen (e.g. in the mud under a pond), where
they're forced to break down their food in a way that involves dumping
electrons into their environment (thus, the bacteria dump electrons
into our electrode). A second electrode is suspended in a body of
water, which can act as a sink for the dumped electrons, and so we can
get a current flowing between the two. If algae are growing in the
water, they can turn sunlight into sugar to be eaten by the generating
bacteria, thus effectively turning the system into a solar cell. Lots
of room for experimentation here: isolating and identifying the most
efficient species/strains of generating bacteria (and fun with
directed evolution to improve this), playing with environmental
conditions (temperature, pH, salinity, light exposure, purity of
culture, etc etc).
We set up a first fuel cell last night, fed with cheese and few salad
leaves as starting biomass. Weird way to set one up so it might not
work, but worth a try until we get some more resources (basically:
mud) together. At the moment it's on the windowsill in the room where
we had our meeting, that used to be the machine shop.
================
Equipment Projects:
Incubator:
We need a warm box (one or two cubic feet will be fine) with a shelf
inside, that we can keep at 37 degrees. Realistically, 35 degrees +/-
3 degrees should be OK. We discussed setting up a system relying on
peltier warmers/coolers with a fan to circulate the air. This would be
great, as we should have good control over temperature and be able to
set e.g. 16 hours at 37 degrees then stay around 4 degrees until
turned off, if we set up a bacterial culture overnight and no-one is
free to come in the next day.
Thermal cycler:
There are several possibilities for thermal cyclers... they turn up on
eBay fairly regularly, or we can build our own. OpenPCR are due to
release their open-source machine, kit, and plans within the next few
months (no set release date, though). Much simpler designs may also be
possible, e.g. with peltier systems or the "lightbulb PCR" system.
These will be cheaper and faster to get hold of, but possibly a lot
more tempermental. They could certainly be a lot of fun to build and
test, though!
Centrifuge:
We'll need a microcentrifugue at some point. We can try printing a new
dremelfuge or getting one machined out of metal (possibly safer
failure characteristics). We're also going to try opening up a "Henry"
vacuum cleaner, as it's already a fairly powerful motor inside a
robust plastic bucket. We need to do some calculations to check the g
forces we could achieve, and we need to keep an eye out for a free or
very cheap Henry.
Vacuum manifold:
Easier and safer alternative to a microcentrifuge for some
applications. Basically a box hooked up to a vacuum source (vacuum
cleaner should be easily good enough), with nozzles on the top to
accommodate a specific fitting common to several molecular biology
kits. Should be an extremely simple build. I'll look into the
measurements for this.
============
Next steps:
A) This information -- along with all that I've forgotten, got wrong
or omitted -- would be useful on the wiki. Maybe a short page for each
project?
B) I will select and find prices for the resources we'll need for the
two least resource-intensive projects: microbiological survey and fuel
cells. I'll put up a wiki page ASAP, followed by a pledge page so we
can get going.
C) Meanwhile, we'll look into building (or buying):
An incubator (should be an easy build, probably the most urgent on
this list)
A thermal cycler (eBay or home-built)
A centrifuge (might take some thought; I'm keen to try printing and
testing a new dremelfugue, when the printer is back in action)
A fridge (ideally with a small freezer compartment)
An electrophoresis tank: plans are available online, so it should just
be finding the materials and laser cutting them?
...Then as these things become available, we can start moving onto the
other cool projects that we've had suggested.
D) Plan another meetup soon. A day where we can build and prototype
some of the equipment, as well as get started on the first experiment.
Wow, that was long!
Thanks again to everyone who came along! Probably most of our meet-ups
in the future will be more practical than talky, unless people are
interested in education sessions?
Have fun,
Bugs
[1]http://en.wikipedia.org/wiki/18S_ribosomal_RNA
[2]http://www.midlandstech.edu/science/kelleherk/225/labmaterials/
sel_diff_media.html
[3]http://en.wikipedia.org/wiki/Endogenous_retrovirus
[4]http://www.pearlbiotech.com/hardware/
[5]http://www.qiagen.com/products/pcr/fastcycling/
qiagenfastcyclingpcrkit.aspx ...or similar
[6]http://www.microbialfuelcell.org/
Adrian Godwin
Jan 16, 2011, 12:58:26 PM1/16/11
to london-h...@googlegroups.com
Curry Identification Project:
Similar idea to Food Phylogeny and Detecting GMOs - taking samples of
meat from various curry houses, and checking to see whether they're
actually the meat that they claim to be and whether they're
contaminated with any other species. I'm told (although have never
checked) that some years back, pork DNA was found in chicken breasts
sold in a UK supermarket (some pig product was used in the solution
that gets injected into cheap chicken breasts to bulk them up) which,
understandably, irked a load of religious people. So could be an
interesting one! Requirements are probably the same as those for
Detecting GMOs in foods.
There was a report a few months ago that accused fish & chip shops of selling almost any fish as cod. Could checking this be an interesting alternative ?
Incubator:
We need a warm box (one or two cubic feet will be fine) with a shelf
inside, that we can keep at 37 degrees. Realistically, 35 degrees +/-
3 degrees should be OK. We discussed setting up a system relying on
peltier warmers/coolers with a fan to circulate the air. This would be
great, as we should have good control over temperature and be able to
set e.g. 16 hours at 37 degrees then stay around 4 degrees until
turned off, if we set up a bacterial culture overnight and no-one is
free to come in the next day.
I have a small environmental chamber. It has both heating and refrigeration and a reasonable temperature controller. I don't think it will automatically switch to refrigeration if required - not sure if that's a bug or a design limitation. However it would probably keep 37C pretty well. The chamber is about the size you suggest but insulation and control gear makes the overall machine fairly big .. the size of a small table.
Could this be useful ? I'l gladly bring it in if it won't take too much space.
-adrian
Nigel Worsley
Jan 16, 2011, 5:14:12 PM1/16/11
to london-h...@googlegroups.com
> We set up a first fuel cell last night, fed with cheese and few salad leaves as starting biomass.
That sounds very unscientific. Did you record the variety of cheese :-)
Unfortunately I couldn't make the meeting, it sounds like it was really interesting and that is a great list
of projects.
A few thoughts about equipment:
Although hacking our own PCR machine is a worthwile aim, buying a cheap one from ebay would
help kickstart things. Is this one suitable http://cgi.ebay.co.uk/270691363646 if it is then start a
pledge for it - I am up for �30, and may be able to collect it as well.
One thing that seems to be missing from the list is a power supply for electrophoresis. My limited
understanding of the subject suggests 100V or more is desirable, so the existing supplies in the space
probably aren't going to be very useful. What sort of voltage and current should we be looking for?
How many base pairs are we looking at running a gel for? A good while back I had a discussion
over a beer with a molecular biologist who enthused about the new FIGE (Field Inversion Gel
Electrophoresis) technique. He was working with upto 500,000 base pairs, probably rather more
than the current projects require but why limit our capabilities?
Things have probably moved on a lot since then, but the main requirement seemed to be a computer
controlled polarity switch, very expensive back then but high voltage FETs are fairly cheap now.
The switch timing was varied during the run, and I think the voltage was as well but not under
computer control. Building such a supply with built in switch should be fairly easy, so what
specification is required?
A final thought, would it be practical to modify a scanner to use UV leds as the illumination source
to get a dimensionally accurate high resolution scan of the finished gel?
Nigle
Gilda Maurice
Jan 16, 2011, 5:44:10 PM1/16/11
to london-h...@googlegroups.com
Great find Nigel!
I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
I can put £40 towards the thermal cycler.
Lee Nelson
Jan 16, 2011, 5:58:19 PM1/16/11
to london-h...@googlegroups.com
I someone on the Histonet group mention converting a flatbed scanner into a gel imager by replacing the light with a UV tube. This was done in a professional lab due to lack of funding for a commercial imager.
Nigel Worsley
Jan 16, 2011, 6:57:13 PM1/16/11
to london-h...@googlegroups.com
> Great find Nigel!
> I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
> I can put �40 towards the thermal cycler.
> I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
> I can put �40 towards the thermal cycler.
We are very close to having enough pledges to start bidding on this. Will you do the bidding on this or shall I?
Nigle
Sam Cook
Jan 16, 2011, 6:57:18 PM1/16/11
to london-h...@googlegroups.com
Hi Gilda,
I've moved this section to http://wiki.hackspace.org.uk/wiki/Pledges/Biohacking under the main pledges page, there's a link to it in that section though. I've just created a single biohacking pledges page, if you want you can create further pages from this for individual items. This should mean that people only have to look in one place to find any pledges going on in the hackspace,
Thanks
Sam
I've moved this section to http://wiki.hackspace.org.uk/wiki/Pledges/Biohacking under the main pledges page, there's a link to it in that section though. I've just created a single biohacking pledges page, if you want you can create further pages from this for individual items. This should mean that people only have to look in one place to find any pledges going on in the hackspace,
Thanks
Sam
Sam Cook
Jan 16, 2011, 7:01:22 PM1/16/11
to london-h...@googlegroups.com
Also added a bit on the projects wiki page, it can be found here:
http://wiki.hackspace.org.uk/wiki/Projects#Biohacking
http://wiki.hackspace.org.uk/wiki/Projects#Biohacking
On 16 January 2011 23:57, Nigel Worsley <nig...@googlemail.com> wrote:
Great find Nigel!
I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
I can put Ł40 towards the thermal cycler.
Gilda Maurice
Jan 17, 2011, 4:16:34 AM1/17/11
to london-h...@googlegroups.com
I've already put a bid in :-)
What should our max bid be, do you reckon?
On 16 January 2011 23:57, Nigel Worsley <nig...@googlemail.com> wrote:
Great find Nigel!
I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
I can put Ł40 towards the thermal cycler.
We are very close to having enough pledges to start bidding on this. Will you do the bidding on this or shall I?
Nigle
Martin Dittus
Jan 17, 2011, 4:36:59 AM1/17/11
to london-h...@googlegroups.com
Random search suggests a new one costs $1,000.
Sara Tocchetti
Jan 17, 2011, 11:38:09 AM1/17/11
to london-h...@googlegroups.com
Hi Nigel,
the kind of voltages needed for a electrophoresis are from 10 to 200v , this could help you http://www.coleparmer.com/1/1/71194-thermo-scientific-electrophoresis-power-supply-200v-120v.html
so let us know if you find something, we are trying to builf an electrophoresis box.
For you question about the size of the DNA fragment is rarelly more than 1000pb that I thing we are going to run, not entire genomes, so should not require special techniques such as the FIGE.
thanks for your time,
sara
2011/1/16 Nigel Worsley <nig...@googlemail.com>
Adrian Godwin
Jan 17, 2011, 12:27:28 PM1/17/11
to london-h...@googlegroups.com
How much current ?
That one's specified at 2A, which it calls high. So possibly less is OK for some things. 200V at 2W is a fairly substantial power supply.
I have a rather old PSU that can do 500V but is presently limited to 200mA. It could perhaps be upgraded to 500mA.
Also, there's a Variac on the rack in unit 23, property of /donated by Russ. It's about 1A, I think. Add rectification and smoothing and this would do a reasonable job of it.
-adrian
That one's specified at 2A, which it calls high. So possibly less is OK for some things. 200V at 2W is a fairly substantial power supply.
I have a rather old PSU that can do 500V but is presently limited to 200mA. It could perhaps be upgraded to 500mA.
Also, there's a Variac on the rack in unit 23, property of /donated by Russ. It's about 1A, I think. Add rectification and smoothing and this would do a reasonable job of it.
-adrian
Radek Maciaszek
Jan 17, 2011, 3:02:37 PM1/17/11
to london-h...@googlegroups.com
Hi,
I will be happy to contribute 30£ to it as well. I assume this is the one we want? As I don't know much about this kind of hardware I will leave it to you guys to decide which one is best.
P.S. I guess its too late for this kind of question anyway since there is already a bid on it ;)
Cheers,
Radek
On 16 January 2011 22:14, Nigel Worsley <nig...@googlemail.com> wrote:
Radek Maciaszek
Jan 17, 2011, 3:01:41 PM1/17/11
to london-h...@googlegroups.com
Hi,
I will be happy to contribute 30£ to it as well. I assume this is the one we want? As I don't know much about this kind of hardware I will leave it to you guys to decide which one is best.
P.S. I guess its too late for this kind of question anyway since there is already a bid on it ;)
Cheers,
Radek
On 16 January 2011 22:14, Nigel Worsley <nig...@googlemail.com> wrote:
Bugs
Jan 17, 2011, 4:37:09 PM1/17/11
to London Hackspace
Food species:
Checking fish to see what species they are would probably net us more
mis-sold foods than checking meat IMO, so it's definitely worth adding
to the slate :).
For the electrophoresis power supply:
120V DC is a sensible upper limit: you *can* go higher, but have to
start worrying about melting the gel. The speed at which a gel runs
scales linerarly (ish) with the voltage you put across it, so the
lower limit is defined by how patient you are. 20V will need to be
left overnight, 120V will take about 30-45min for the gel sizes that
we're interested in. I've never timed a gel running at 100V, but it's
probably OK.
I agree with Sara that we're unlikely to need FIGE. Building the
capability for it could be a cool project in the future, but I don't
think we should make it a priority. When or if we start cloning work
(which is dependent on antibiotic availability and various legal
issues getting sorted), the maximum I can see us needing is around
10,000bp which runs very well using an ordinary DC supply.
The powerpacks in my lab max out at 400mA, which is comfortably enough
for three large gel tanks, each roughly double the size of the Pearl
Biotech tank that Sara is interested in building. So I expect that we
could happily get away with 200mA, and that the 2A supply is far more
than we'll ever need.
Thermal cycler:
As well as the cool retro stylings, the thermal cycler that Gilda has
bid on does look good for us. Might not be the simplest thing to
program but, luckily, we're all great :). A quick root through a few
second hand lab equipment sites puts the going rate for this model at
around $750.
UV Scanner:
I really like this idea, probably much better for us than the normal
approach of using an illuminated "table" (transilluminator) and taking
photos in the dark through a filtered lens. We'd need to be careful
about making it fairly light-tight of course... I've known several
people get funky tan lines in the lab from leaning over their gel on a
UV source for too long! We might be able to get away with using
high(ish) frequency blue light. The transilluminator I use in my lab
is blue (as opposed to UV); you get a somewhat dimmer signal, but it's
safer and probably cheaper.
On Jan 17, 8:01 pm, Radek Maciaszek <ra...@maciaszek.co.uk> wrote:
> Hi,
>
> I will be happy to contribute 30£ to it as well. I assume this is the one we
> want? As I don't know much about this kind of hardware I will leave it to
> you guys to decide which one is best.
>
> P.S. I guess its too late for this kind of question anyway since there is
> already a bid on it ;)
>
> Cheers,
> Radek
>
> On 16 January 2011 22:14, Nigel Worsley <nig...@googlemail.com> wrote:
>
> > We set up a first fuel cell last night, fed with cheese and few salad
> >> leaves as starting biomass.
>
> > That sounds very unscientific. Did you record the variety of cheese :-)
>
> > Unfortunately I couldn't make the meeting, it sounds like it was really
> > interesting and that is a great list
> > of projects.
>
> > A few thoughts about equipment:
>
> > Although hacking our own PCR machine is a worthwile aim, buying a cheap one
> > from ebay would
> > help kickstart things. Is this one suitable
> >http://cgi.ebay.co.uk/270691363646if it is then start a
Checking fish to see what species they are would probably net us more
mis-sold foods than checking meat IMO, so it's definitely worth adding
to the slate :).
For the electrophoresis power supply:
120V DC is a sensible upper limit: you *can* go higher, but have to
start worrying about melting the gel. The speed at which a gel runs
scales linerarly (ish) with the voltage you put across it, so the
lower limit is defined by how patient you are. 20V will need to be
left overnight, 120V will take about 30-45min for the gel sizes that
we're interested in. I've never timed a gel running at 100V, but it's
probably OK.
I agree with Sara that we're unlikely to need FIGE. Building the
capability for it could be a cool project in the future, but I don't
think we should make it a priority. When or if we start cloning work
(which is dependent on antibiotic availability and various legal
issues getting sorted), the maximum I can see us needing is around
10,000bp which runs very well using an ordinary DC supply.
The powerpacks in my lab max out at 400mA, which is comfortably enough
for three large gel tanks, each roughly double the size of the Pearl
Biotech tank that Sara is interested in building. So I expect that we
could happily get away with 200mA, and that the 2A supply is far more
than we'll ever need.
Thermal cycler:
As well as the cool retro stylings, the thermal cycler that Gilda has
bid on does look good for us. Might not be the simplest thing to
program but, luckily, we're all great :). A quick root through a few
second hand lab equipment sites puts the going rate for this model at
around $750.
UV Scanner:
I really like this idea, probably much better for us than the normal
approach of using an illuminated "table" (transilluminator) and taking
photos in the dark through a filtered lens. We'd need to be careful
about making it fairly light-tight of course... I've known several
people get funky tan lines in the lab from leaning over their gel on a
UV source for too long! We might be able to get away with using
high(ish) frequency blue light. The transilluminator I use in my lab
is blue (as opposed to UV); you get a somewhat dimmer signal, but it's
safer and probably cheaper.
On Jan 17, 8:01 pm, Radek Maciaszek <ra...@maciaszek.co.uk> wrote:
> Hi,
>
> I will be happy to contribute 30£ to it as well. I assume this is the one we
> want? As I don't know much about this kind of hardware I will leave it to
> you guys to decide which one is best.
>
> P.S. I guess its too late for this kind of question anyway since there is
> already a bid on it ;)
>
> Cheers,
> Radek
>
> On 16 January 2011 22:14, Nigel Worsley <nig...@googlemail.com> wrote:
>
> > We set up a first fuel cell last night, fed with cheese and few salad
> >> leaves as starting biomass.
>
> > That sounds very unscientific. Did you record the variety of cheese :-)
>
> > Unfortunately I couldn't make the meeting, it sounds like it was really
> > interesting and that is a great list
> > of projects.
>
> > A few thoughts about equipment:
>
> > Although hacking our own PCR machine is a worthwile aim, buying a cheap one
> > from ebay would
> > help kickstart things. Is this one suitable
Bugs
Jan 17, 2011, 4:58:11 PM1/17/11
to London Hackspace
Thinking of the GM food project, this looks interesting:
http://www.carolina.com/product/life+science/biotechnology+kits+%26+materials/polymerase+chain+reaction+%28pcr%29/gm+food+extraction+and+amplification+kit+with+0.5-ml+tubes+%28with+prepaid+coupon%29.do?sortby=ourPicks
It's a very complete-looking kit to detect a specific gene that's
commonly inserted into wheat and soy. We'd need to supply basic
equipment: thermal cycler, pipettes, electrophoresis tank and power
supply. All the chemicals and enzymes are in the kit, including GM and
non-GM soya beans to act as positive and negative controls. I've just
skimmed the manual, which is a bit technical in parts but might be an
interesting read for anyone interested in our own version of this
project.
It isn't cheap ($180 for 24 reactions) and it's not very
generalisible, in that the leftovers -- if any -- might not be
terribly useful to us. But it's potentially a fast and reliable way to
get some results for that project, if anyone is really keen to get
started. At the very least, it'll be worth bearing in mind as we price
up the necessary stuff to get our projects up and running.
> > >http://cgi.ebay.co.uk/270691363646ifit is then start a
http://www.carolina.com/product/life+science/biotechnology+kits+%26+materials/polymerase+chain+reaction+%28pcr%29/gm+food+extraction+and+amplification+kit+with+0.5-ml+tubes+%28with+prepaid+coupon%29.do?sortby=ourPicks
It's a very complete-looking kit to detect a specific gene that's
commonly inserted into wheat and soy. We'd need to supply basic
equipment: thermal cycler, pipettes, electrophoresis tank and power
supply. All the chemicals and enzymes are in the kit, including GM and
non-GM soya beans to act as positive and negative controls. I've just
skimmed the manual, which is a bit technical in parts but might be an
interesting read for anyone interested in our own version of this
project.
It isn't cheap ($180 for 24 reactions) and it's not very
generalisible, in that the leftovers -- if any -- might not be
terribly useful to us. But it's potentially a fast and reliable way to
get some results for that project, if anyone is really keen to get
started. At the very least, it'll be worth bearing in mind as we price
up the necessary stuff to get our projects up and running.
Adrian Godwin
Jan 17, 2011, 5:18:56 PM1/17/11
to london-h...@googlegroups.com
On Mon, Jan 17, 2011 at 9:37 PM, Bugs <bu...@binny.eu> wrote:
For the electrophoresis power supply:
120V DC is a sensible upper limit: you *can* go higher, but have to
start worrying about melting the gel. The speed at which a gel runs
scales linerarly (ish) with the voltage you put across it, so the
lower limit is defined by how patient you are. 20V will need to be
left overnight, 120V will take about 30-45min for the gel sizes that
we're interested in. I've never timed a gel running at 100V, but it's
probably OK.
-adrian
Nigel Worsley
Jan 17, 2011, 5:30:31 PM1/17/11
to london-h...@googlegroups.com
> Fairly easily solved then - there's a Weir PSU in the lab that will do 60V at 1A
Looks like we are sorted then, at least to begin with.
I like the idea of designing our own affordable supply in the longer term, but I need to finish several
existing projects before I start another one. Your higher voltage one may well be called upon!
Nigle
Gilda Maurice
Jan 18, 2011, 3:38:49 AM1/18/11
to london-h...@googlegroups.com
We won the PCR! £120. Well that was easy :-)
I have a friend who lives half the time in Kent - I'll ask him if he
can go and collect the machine for us. If that doesnt work out, does
anyone have a car we can use? Maybe the hackvan? I'll email the seller
and ask for their exact location.
On 16 Jan 2011, at 23:57, Nigel Worsley <nig...@googlemail.com> wrote:
>> Great find Nigel!
>> I've added a pledge section to the biohacking page: http://wiki.hackspace.org.uk/wiki/Biohacking#Pledges
>> I can put �40 towards the thermal cycler.
Martin Dittus
Jan 18, 2011, 4:30:23 AM1/18/11
to london-h...@googlegroups.com
At that price we could rent a car from pledge money. I can drive, though it looks like I'll be busy this coming weekend.
Or risk shipping it with parcel2go (cheap but only "96% success rate".)
m.
cassj
Jan 18, 2011, 6:26:05 AM1/18/11
to London Hackspace
On Jan 18, 8:38 am, Gilda Maurice <gmaur...@gmail.com> wrote:
> We won the PCR! £120. Well that was easy :-)
> I have a friend who lives half the time in Kent - I'll ask him if he
> can go and collect the machine for us. If that doesnt work out, does
> anyone have a car we can use? Maybe the hackvan? I'll email the seller
> and ask for their exact location.
We can probably pick it up at the weekend if you like? How big is it?
Cass xx
> --
> gmaur...@gmail.com
Nigel Worsley
Jan 18, 2011, 6:33:58 AM1/18/11
to london-h...@googlegroups.com
> We can probably pick it up at the weekend if you like? How big is it?
According to a website I found:
Weight: 57 lbs.
Measurements: 13 x 19 x 12
Not huge, but rather heavy!
Nigle
cassj
Jan 18, 2011, 6:46:45 AM1/18/11
to London Hackspace
> Weight: 57 lbs.
> Measurements: 13 x 19 x 12
>
> Not huge, but rather heavy!
Hmm. Should fit ok if we put one of the back seats down. Would leave
> Measurements: 13 x 19 x 12
>
> Not huge, but rather heavy!
space for an extra body in the car to help with the heavy lifting if
anyone fancies volunteering?
Cass.
Gilda Maurice
Jan 18, 2011, 6:55:32 AM1/18/11
to london-h...@googlegroups.com
I've asked the seller if we can pick up the machine this weekend.
However their address is Sittingbourne Research Centre, Kent ME98HL United Kingdom
so the seller (Steve) might not be working this weekend.
In which case Parcel2Go can do a next-day delivery of a 25kg parcel for £14, including insurance up to £120!!
Which sounds amazingly cheap to me.
Should we trust them?
Nigel Worsley
Jan 18, 2011, 7:02:39 AM1/18/11
to london-h...@googlegroups.com
> Parcel2Go can do a next-day delivery of a 25kg parcel for �14, including insurance up to �120!!
By my calculation it weighs 25.9kg. Plus packing.
Nigle
Andrew Cousins
Jan 18, 2011, 2:07:32 PM1/18/11
to london-h...@googlegroups.com
then disappeared for three days, sorry). If we've got a suitable
supply already, good.
If we decide to roll our own regardless (I like that idea also),
it seems a reasonable minimum spec is:
40 to 120V adjustable, galvanically isolated from the input
200mA (at 120V this is 24W, do we want an adjustable current limit?)
timer (20 minutes to 24h)
Nice to have, why do things by halves? :) :
20 to 200V
400mA (definitely with adjustable current limit, 80W at 200V)
programmable profile over time, including reverse
We would also need to pick a physical format and user interface
and a remote control interface.
Andrew
--
Andrew Cousins
A little inaccuracy sometimes saves tons of explanation.
-- H.H. Munro, "Saki"
Andrew Cousins
Jan 18, 2011, 2:08:39 PM1/18/11
to london-h...@googlegroups.com, a...@thebookgallery.ca
On 16/01/11 17:58, Adrian Godwin wrote:
>>
[SNIP]
>> Incubator:
>> We need a warm box (one or two cubic feet will be fine) with a shelf
>> inside, that we can keep at 37 degrees. Realistically, 35 degrees +/-
>> 3 degrees should be OK. We discussed setting up a system relying on
>> peltier warmers/coolers with a fan to circulate the air. This would be
>> great, as we should have good control over temperature and be able to
>> set e.g. 16 hours at 37 degrees then stay around 4 degrees until
>> turned off, if we set up a bacterial culture overnight and no-one is
>> free to come in the next day.
>>
>>
> I have a small environmental chamber. It has both heating and refrigeration
> and a reasonable temperature controller. I don't think it will automatically
> switch to refrigeration if required - not sure if that's a bug or a design
> limitation. However it would probably keep 37C pretty well. The chamber is
> about the size you suggest but insulation and control gear makes the overall
> machine fairly big .. the size of a small table.
> Could this be useful ? I'l gladly bring it in if it won't take too much
> space.
>
> -adrian
>
>>
[SNIP]
>> Incubator:
>> We need a warm box (one or two cubic feet will be fine) with a shelf
>> inside, that we can keep at 37 degrees. Realistically, 35 degrees +/-
>> 3 degrees should be OK. We discussed setting up a system relying on
>> peltier warmers/coolers with a fan to circulate the air. This would be
>> great, as we should have good control over temperature and be able to
>> set e.g. 16 hours at 37 degrees then stay around 4 degrees until
>> turned off, if we set up a bacterial culture overnight and no-one is
>> free to come in the next day.
>>
>>
> I have a small environmental chamber. It has both heating and refrigeration
> and a reasonable temperature controller. I don't think it will automatically
> switch to refrigeration if required - not sure if that's a bug or a design
> limitation. However it would probably keep 37C pretty well. The chamber is
> about the size you suggest but insulation and control gear makes the overall
> machine fairly big .. the size of a small table.
> Could this be useful ? I'l gladly bring it in if it won't take too much
> space.
>
> -adrian
>
On Saturday I also mentioned that for an incubator we could look
at what this guy uses for a DIY thermal chamber for electronics:
http://www.eevblog.com/2010/07/25/eevblog-101-hacking-your-own-peltier-lab-thermal-chamber/
It seems to be a 19 litre beer fridge / pie warmer, driven by a
peltier.
http://www.amazon.com/gp/product/B001F7H4RY?ie=UTF8&tag=ee04-20&linkCode=as2&camp=1789&creative=390957&creativeASIN=B001F7H4RY
A search on Google UK for cooler and warmer turns up a 14 litre
food warmer/ cooler for �51 from Argos. I assume this is also
driven by a peltier, there are no specs on accuracy or how much
load it can handle:
http://www.argos.co.uk/static/Product/partNumber/9248832.htm?_$ja=tsid:11527|cc:|prd:9248832|cat:gifts+and+hobbies+%2F+mini+fridges+and+water+dispensers+%2F
It does say that it can only pull to 18 degrees below ambient,
which might not be enough.
To get a timed temperature profile we would have to hack it. If
we don't hack it for the timed profile we might as well get an
oven that can be set to 37C reasonably accurately (how often will
the space be warmer than that?).
If we use Adrian's proper environmental chamber then this is all
moot of course.
Andy
Nigel Worsley
Jan 18, 2011, 4:21:50 PM1/18/11
to london-h...@googlegroups.com
> it seems a reasonable minimum spec is:
> 40 to 120V adjustable, galvanically isolated from the input
> 200mA (at 120V this is 24W, do we want an adjustable current limit?)
> timer (20 minutes to 24h)
>
> Nice to have, why do things by halves? :) :
> 20 to 200V
> 400mA (definitely with adjustable current limit, 80W at 200V)
> programmable profile over time, including reverse
> 40 to 120V adjustable, galvanically isolated from the input
> 200mA (at 120V this is 24W, do we want an adjustable current limit?)
> timer (20 minutes to 24h)
>
> Nice to have, why do things by halves? :) :
> 20 to 200V
> 400mA (definitely with adjustable current limit, 80W at 200V)
> programmable profile over time, including reverse
I was looking into doing an isolated 20-200V supply at 200mA, initially a dumb one and adding processor control
later.. It should be easy to increase to 400mA, but I suspect that will only be necessary for runnning multiple gels
and I prefer the flexibility of a pair of 200mA supplies independently controlled. The extra cost of doing it this way
should be less than �10.
> We would also need to pick a physical format and user interface
I was thinking og a graphic LCD, mainly because I already use them in a product. I have some small (2.4"?) TFT
displays that I haven't got around to using, over the top but it would look very nice, may use them instead.
> and a remote control interface.
USB is trivial, ethernet is a bit more work but would allow checking progress over the internet. Not at all sure about
allowing control over it though, could be dangerous.
Nigle
Nigel Worsley
Jan 18, 2011, 4:26:53 PM1/18/11
to london-h...@googlegroups.com
> It does say that it can only pull to 18 degrees below ambient, which might not be enough.
This one will cool by 27 degrees and heat up to 65 degrees (absolute I think, presumably the plastic won't cope with more)
http://cgi.ebay.co.uk/220725833946
I have already put a bid in on this as I can make use of it myself if the space doesn't want it.
> To get a timed temperature profile we would have to hack it.
That's what we do, isn't it?
How accurate does the temperature have to be? 1 degree is not too difficult but anything better will get expensive.
Nigle
Gilda Maurice
Jan 18, 2011, 5:38:47 PM1/18/11
to london-h...@googlegroups.com
I was thinking of simply putting a box box behind the hackspace fridge and measuring how warm it gets inside - might possibly be a good solution! If it's not warm enough, then I was going to try and light lightbulbs of various intensities in the box until a constant 37C is reached.
However we do seem to have spare money from the PCR pledge so maybe we can buy a ready-made solution.
Adrian Godwin
Jan 18, 2011, 5:41:14 PM1/18/11
to london-h...@googlegroups.com
What temperature does a yoghurt maker run at ?
-adrian
-adrian
Gilda Maurice
Jan 18, 2011, 6:12:10 PM1/18/11
to london-h...@googlegroups.com
On 18 January 2011 21:26, Nigel Worsley <nig...@googlemail.com> wrote:
This one will cool by 27 degrees and heat up to 65 degrees (absolute I think, presumably the plastic won't cope with more) http://cgi.ebay.co.uk/220725833946It does say that it can only pull to 18 degrees below ambient, which might not be enough.
I have already put a bid in on this as I can make use of it myself if the space doesn't want it.
That looks ideal. I live and work near the hackspace so I could come in the morning and change it from 37C to 4C manually in the morning before I go to work. And when I'm not here we can always ask whoever is in the space to do it for us, That's probably an ok solution for now!
Should we add this to the pledge page?
Gilda Maurice
gmau...@gmail.com
Bugs
Jan 19, 2011, 7:39:08 AM1/19/11
to London Hackspace
===Cycler===
I'll be free on Sunday afternoon if needed to help heft the cycler.
Just promise not to mock my puny arms :).
===Incubator===
If that box can maintain its temperature with decent accuracy, it does
look ideal. In an ideal world we're after 37 +/- 2, but 35+/- 4 would
probably be fine. Any idea if it can be set to an absolute
temperature, or will it be relative to the temperature in the room? If
the latter, we'd need to put our own thermostat in there.
Do we have (or can we easily set up) a temperature probe + logger?
It'd be nice to test it in advance, just leave it running for a day or
two and see how much the temperature fluctuates.
Cooling isn't too important. There's nothing magic about 4 degrees,
it's just that the cooler we keep these things the longer we can leave
plates in there before having to do something with them. In the longer
term we're going to need a dedicated fridge (ideally with freezer
space) anyway.
===Gel running===
Using the existing power supply at 60V will mean running some slow
gels, but I'm inclined to suggest doing that while taking slightly
longer to build the fancy power supply that Andrew and Nigel are
describing.
I agree with Sara that the Pearl Biotech tank is probably the way to
go. We could order a kit but, from skimming the plans (http://
www.pearlbiotech.com/hardware/) we should be able to whip one out on
the laser cutter with very little effort. Any volunteers to look into
getting the materials?
The idea of putting a UV tube into a scanner is great. Are there any
scanners in the space, or will we need to scrounge one? Are UV tubes
expensive?
===Pledges===
People who've pledged: as we've pledged quite a bit more than the cost
of the thermal cycler, is it OK to redistribute the excess to other
bits of essential kit for the DIYBio work? Obviously we'll check with
the pledgers before spending any of it. Or would it be better form to
only take what's needed and wipe the slate clean for future pledges?
> gmaur...@gmail.com
I'll be free on Sunday afternoon if needed to help heft the cycler.
Just promise not to mock my puny arms :).
===Incubator===
If that box can maintain its temperature with decent accuracy, it does
look ideal. In an ideal world we're after 37 +/- 2, but 35+/- 4 would
probably be fine. Any idea if it can be set to an absolute
temperature, or will it be relative to the temperature in the room? If
the latter, we'd need to put our own thermostat in there.
Do we have (or can we easily set up) a temperature probe + logger?
It'd be nice to test it in advance, just leave it running for a day or
two and see how much the temperature fluctuates.
Cooling isn't too important. There's nothing magic about 4 degrees,
it's just that the cooler we keep these things the longer we can leave
plates in there before having to do something with them. In the longer
term we're going to need a dedicated fridge (ideally with freezer
space) anyway.
===Gel running===
Using the existing power supply at 60V will mean running some slow
gels, but I'm inclined to suggest doing that while taking slightly
longer to build the fancy power supply that Andrew and Nigel are
describing.
I agree with Sara that the Pearl Biotech tank is probably the way to
go. We could order a kit but, from skimming the plans (http://
www.pearlbiotech.com/hardware/) we should be able to whip one out on
the laser cutter with very little effort. Any volunteers to look into
getting the materials?
The idea of putting a UV tube into a scanner is great. Are there any
scanners in the space, or will we need to scrounge one? Are UV tubes
expensive?
===Pledges===
People who've pledged: as we've pledged quite a bit more than the cost
of the thermal cycler, is it OK to redistribute the excess to other
bits of essential kit for the DIYBio work? Obviously we'll check with
the pledgers before spending any of it. Or would it be better form to
only take what's needed and wipe the slate clean for future pledges?
Nigel Worsley
Jan 19, 2011, 7:54:07 AM1/19/11
to london-h...@googlegroups.com
> Do we have (or can we easily set up) a temperature probe + logger?
I have a dual thermocouple digital thermometer. I can also borrow one of these from work:
http://www.picotech.com/thermocouple.html#buy It hasn't been used for years, nobody
would miss it for a while.
> The idea of putting a UV tube into a scanner is great. Are there any
> scanners in the space, or will we need to scrounge one?
One got junked a while back, I think it was because there were too many of them lying around.
> Are UV tubes expensive?
Depends on the wavelength. I was thinking of using LEDs, replace the RGB LEDs of the scanner with UV
ones and job done :-)
Maybe an interlock switch on the lid for safety.
> People who've pledged: as we've pledged quite a bit more than the cost
> of the thermal cycler, is it OK to redistribute the excess to other
> bits of essential kit for the DIYBio work?
Fine with me.
Nigle
Meurig Freeman
Jan 19, 2011, 7:54:55 AM1/19/11
to london-h...@googlegroups.com
> The idea of putting a UV tube into a scanner is great. Are there any
> scanners in the space, or will we need to scrounge one? Are UV tubes
> expensive?
I may be able to put my hands on an old flatbed scanner if it would be helpful.> scanners in the space, or will we need to scrounge one? Are UV tubes
> expensive?
I don't think there's a power supply with it, but I imagine a new supply would be required for a UV tube anyway?
--
Meurig
Martin Dittus
Jan 19, 2011, 8:05:34 AM1/19/11
to london-h...@googlegroups.com
>> People who've pledged: as we've pledged quite a bit more than the cost
>> of the thermal cycler, is it OK to redistribute the excess to other
>> bits of essential kit for the DIYBio work?
>
> Fine with me.
>> of the thermal cycler, is it OK to redistribute the excess to other
>> bits of essential kit for the DIYBio work?
>
> Fine with me.
Yes of course.
m.
Irwin Zaid
Jan 19, 2011, 7:56:34 AM1/19/11
to london-h...@googlegroups.com
>> People who've pledged: as we've pledged quite a bit more than the cost
>> of the thermal cycler, is it OK to redistribute the excess to other
>> bits of essential kit for the DIYBio work?
>> of the thermal cycler, is it OK to redistribute the excess to other
>> bits of essential kit for the DIYBio work?
Yes, please do.
Irwin
Gilda Maurice
Jan 19, 2011, 8:27:21 AM1/19/11
to london-h...@googlegroups.com
No problem!
--
Gilda Maurice
gmau...@gmail.com
People who've pledged: as we've pledged quite a bit more than the cost
of the thermal cycler, is it OK to redistribute the excess to other
bits of essential kit for the DIYBio work?
Gilda Maurice
gmau...@gmail.com
caroline johnston
Jan 19, 2011, 8:30:59 AM1/19/11
to london-h...@googlegroups.com
On 19 January 2011 12:39, Bugs <bu...@binny.eu> wrote:
> ===Cycler===
> I'll be free on Sunday afternoon if needed to help heft the cycler.
> Just promise not to mock my puny arms :).
> ===Cycler===
> I'll be free on Sunday afternoon if needed to help heft the cycler.
> Just promise not to mock my puny arms :).
Tom says he's happy to drive to Kent to pick the thing up, but is less
keen on driving through London. Do you think we'd be able to get it on
a train at Forest Hill and off again at Hoxton?
scary boots
Jan 19, 2011, 8:44:48 AM1/19/11
to london-h...@googlegroups.com
I own an old flatbed scanner which i don't use as it has a parallel port and nothing else I own does. It does have a power supply. Would it be any use?
Gilda Maurice
Jan 19, 2011, 8:43:27 AM1/19/11
to london-h...@googlegroups.com
It's over 25kgs! You'll need one of these: http://www.cupboardsdirect.co.uk/store/assets/product/ECONSTRAIGHTSACKTRUCK.jpg
Nigel Worsley
Jan 23, 2011, 9:22:37 AM1/23/11
to london-h...@googlegroups.com
I won the auction on the thermoelectric coolbox: http://cgi.ebay.co.uk/220725833946
We will need a fairly beefy 12V power supply for it, is there a spare one in the space?
I should finally get the ethernet arduino board finished in the next few days, this would be
ideal for controlling it :-)
Nigle
Adrian Godwin
Jan 23, 2011, 9:44:33 AM1/23/11
to london-h...@googlegroups.com
-adrian
James Harrison
Jan 23, 2011, 9:53:24 AM1/23/11
to london-h...@googlegroups.com
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If it's expecting a car power source for normal operation it won't be
that much; if it's just a peltier heat pump and some fans probably a
few hundred mA tops I'd have thought.
James
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Nigel Worsley
Jan 23, 2011, 10:25:33 AM1/23/11
to london-h...@googlegroups.com
> Don't think there's anything much above about 2A in the space. What will it need ?
Somewhere between 5 and 10 amps at a rough guess. I have an 18 amp one I can loan
until we can sort out a flashy automated one.
Nigle
Adrian Godwin
Jan 23, 2011, 4:55:15 PM1/23/11
to london-h...@googlegroups.com
One possibility is the stack of power supply modules that came from the BBC (in a linbin in hangar 23). They seem to be mostly 24V at 2.5A and 5V at 8A. Maybe they could be linked up, or the peltiers rearranged to match one of those voltages.
-adrian
Nigel Worsley
Jan 23, 2011, 5:26:53 PM1/23/11
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> One possibility is the stack of power supply modules that came from the BBC (in a linbin in hangar 23)
> They seem to be mostly 24V at 2.5A and 5V at 8A. Maybe they could be linked up, or the peltiers
> rearranged to match one of those voltages.
> rearranged to match one of those voltages.
The cooler claims autoswitching between 12V and 24V, 2.5A may be enough. If not then it should be possible
to bodge a pair together. Are these proper supplies or something that the BBC kludged together?
Nigle
Adrian Godwin
Jan 23, 2011, 5:30:28 PM1/23/11
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-adrian
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