Dremelfuge, the one-piece low-cost centrifuge

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Cathal Garvey

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Dec 29, 2009, 9:58:07 AM12/29/09
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Dremelfuge is a rotor designed to fit standard lab microcentrifuge tubes and miniprep/purification columns, to be spun by either a powerdrill or other chuck-loading machine or by a popular rotary tool.

Dremelfuge features an easy click-in loading system which holds tubes parallel to the plane of rotation for optimum pelleting and delivery of force.

Intended basic applications of Dremelfuge include column purification (tested to work with miniprep columns) and bacterial/cell debris pelleting (under testing). With standard microcentrifuge tubes, the average rotary distance is 4cms.

Dremelfuge is open-source hardware. Source files are available on Thingiverse, linked from the items on Shapeways. The Creative Commons license used entitles copying, sharing and remixing for any non commercial purpose. Please consider that professional printing services qualify as commercial use.

Two editions of Dremelfuge are available for purchase at
www.shapeways.com/shops/labsfromfabs

One has an axle which can be gripped in a chuck fitting. The other is intended for fitting to a cutting-disc-holder for rotary tools such as a dremel*.

Please share your results and experiences on Thingiverse!

Note: Although I have shown Dremelfuge to work at 3000rpm/400rcf, and intend shortly to test at dramatically higher speeds on a low-cost rotary tool, I don't endorse or recommend use of Dremelfuge as anything but an ornament. Dremelfuge poses a serious safety hazard if used for any other purpose. Please take every precaution if you decide to take such risks. Further advice on Thingiverse.

*Design assumes a disc holder diameter of 3mm and a screw diameter of 2mm. Other designs available on request.

Bryan Bishop

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Dec 29, 2009, 12:23:36 PM12/29/09
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On Tue, Dec 29, 2009 at 8:58 AM, Cathal Garvey <cathal...@gmail.com> wrote:
> Dremelfuge is a rotor designed to fit standard lab microcentrifuge tubes and
> miniprep/purification columns, to be spun by either a powerdrill or other
> chuck-loading machine or by a popular rotary tool.

I looked around and I can't seem to find any solid models. Are there
any .STEP or .IGES files for this design? Thanks.

- Bryan
http://heybryan.org/
1 512 203 0507

Cathal Garvey

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Dec 29, 2009, 3:12:41 PM12/29/09
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I'm afraid not: Makerbot (my prototyper and the standard for Thingiverse) uses .stl, as do Shapeways. I've never had cause to use any other format. However, you might find a way to convert either the stl or .off format outputs that OpenSCAD uses as .step. Let me know if you do: I hunted for a converter before to no avail.

Tonight, I print and test Dremelfuge on the rotary tool it was named for. At 10krpm, that'll mean 4400g on an eppie. If you don't hear from me later, I've probably injured myself trying.

On Dec 29, 2009 5:23 PM, "Bryan Bishop" <kan...@gmail.com> wrote:

On Tue, Dec 29, 2009 at 8:58 AM, Cathal Garvey <cathal...@gmail.com> wrote: > Dremelfuge is a rot...

I looked around and I can't seem to find any solid models. Are there
any .STEP or .IGES files for this design? Thanks.

- Bryan
http://heybryan.org/
1 512 203 0507


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Paul Anderson

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Dec 29, 2009, 3:14:37 PM12/29/09
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On Tue, Dec 29, 2009 at 9:58 AM, Cathal Garvey <cathal...@gmail.com> wrote:
> Dremelfuge is a rotor designed to fit standard lab microcentrifuge tubes and
> miniprep/purification columns, to be spun by either a powerdrill or other
> chuck-loading machine or by a popular rotary tool.
>
>
In honour of your name, I hereby present you with: ONE INTERNETS!
Congratulations!


--
Paul Anderson
VE3HOP
wacky...@gmail.com
http://www.andersonloco.com
QRP ARCI #13228, GQRP #12447

Bryan Bishop

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Dec 29, 2009, 3:42:24 PM12/29/09
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On Tue, Dec 29, 2009 at 2:12 PM, Cathal Garvey <cathal...@gmail.com> wrote:
> I'm afraid not: Makerbot (my prototyper and the standard for Thingiverse)
> uses .stl, as do Shapeways. I've never had cause to use any other format.

You can convert from .STEP or .IGES to .STL, but you can't go the
other way around. This is why I really really recommend you do all of
your designing in CAD tools instead of meshers. You can always get a
mesh from a solid geometry model, and even run it through on a
makerbot, but when you only have a mesh, you limit the number of tools
the artifact can be made on. :-(

I suggest HeeksCAD for starters.

http://code.google.com/p/heekscad/

Nathan McCorkle

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Dec 29, 2009, 4:23:04 PM12/29/09
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are there any designs that aren't orthogonally arranged in relation to the axis of rotation? sometimes its useful for cells to be pelleted along the edge of a tube, that way you can aspirate off more fluid than you could if the pellet was at the bottom.

very cool btw!!! we could throw this into a bowl for safety or something

On Tue, Dec 29, 2009 at 9:58 AM, Cathal Garvey <cathal...@gmail.com> wrote:

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Cathal Garvey

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Dec 29, 2009, 4:45:42 PM12/29/09
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Yea, I'll be spinning mine in a metal pot for safety!

Just a note for those seeking the recessed "Dremel" edition, it's down while I replace it with a more properly sized one. One that should actually fit the Dremel cutting-tool-holder widget. It'll be back shortly!

Thanks to everyone for the positive feedback. And sorry about the mesh Bryan!

Bryan Bishop

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Dec 29, 2009, 4:46:53 PM12/29/09
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On Tue, Dec 29, 2009 at 3:45 PM, Cathal Garvey wrote:
> Thanks to everyone for the positive feedback. And sorry about the mesh
> Bryan!

I was wondering if you would be willing to make another version of the design?

Cathal Garvey

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Dec 29, 2009, 4:52:06 PM12/29/09
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Well, the design is currently made in OpenSCAD, which doesn't support outputs besides .stl and .off. OpenSCAD and Sketchup are my suites of choice and I haven't worked with Solids before.

At some point I may learn another language for solid designing and re:make it, but at the moment I'm occupying my time testing the current version on a Dremel. If you're handy with a modeller, I invite you to replicate it though? Provided I could get a copy of the resulting source/model for Thingiverse, in case others need a solid too.

Cathal Garvey

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Dec 29, 2009, 7:05:58 PM12/29/09
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Quick update: Dremelfuge works comfortably at 10krpm. It can exert a maximum RCF of about 52000g, more than enough to shatter microcentrifuge tubes as it turns out. Dremelfuge itself is completely undamaged after this abuse.

This means that, when used within the speed envelope corresponding to normal lab forces (no faster than 16,680 rpm, or 14k RCF), Dremelfuge should be perfect for any DIYbio applications. It even evinced a robust disregard for unbalanced tubes.

As always, for reasons of liability I do not endorse use of Dremelfuge as anything but an Ornament.

Video forthcoming.

keen101

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Dec 29, 2009, 5:45:07 PM12/29/09
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hi, im new on the list, so im not sure what i might have missed.

Anyway, i like the idea of a low-cost centrifuge, but isn't the idea
of using a dremel tool a bit junky?
I understand the idea is to use parts that are cheap and available
anywhere, but it seems to me if many of the people here already have
makerbots or repraps, then it wouldn't be too much of a step to get a
decent motor with a speed controller circuit hooked up?

That way it would be safer, more usable, and more professional? Sorry
if i misunderstood something. Anyway, great work so far! Keep up the
good work.

(oh, and by the way i dont have a reprap or makerbot, but i wish i
did.)

-Andrew Barney
Northern Colorado

Cathal Garvey

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Dec 29, 2009, 8:16:45 PM12/29/09
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Hi Andrew,
You're quite right: A more complicated device that had better control systems and support would be a superior piece of lab equipment. These exist today, and cost over a grand, and occupy a large area on a workbench.

Dremelfuge was explicitly designed to be:
A) Cheap
B) Accessible
C) Simple

All in all I think I've done very well achieving these ends. If I were to have made it more complicated in any way, it would have cost far more to produce, and wouldn't have been possible to sell through Shapeways (which requires no investment from me and keeps the costs/complexity of manufacture low).

As things stand, I have demonstrated the Dremelfuge to work with Drills, dremels, minipreps and eppies. It is officially the cheapest available centrifuge, even including the cost of a totally basic rotary tool, and can equal or exceed professional-level centrifuges in terms of RCF applied to samples. Used properly, it can be used for any lab procedure requiring a microcentrifuge.*

Personally, I'm pretty happy with my "Junky" design. :)
-Cathal

*Don't use dremelfuge as anything but an ornament. ;)

Cathal Garvey

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Dec 29, 2009, 9:20:41 PM12/29/09
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A demo of Dremelfuge is now up on Youtube: http://www.youtube.com/watch?v=86WnXeTZO_Y

Please excuse my eccentric appearance and inability to avoid saying "ah" in the first ten seconds. Focus on the science people, the science!

wulfdesign

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Dec 29, 2009, 10:07:19 PM12/29/09
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I can't currently use OpenSCAD but will look at the .stl file and see
if I can convert it to STEP. in Rhino3D.

I've got a couple of ideas I'd like to try out on the conversion
process (by hand).
this is as good a file to try it with as any.

-L

Bryan Bishop

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Dec 29, 2009, 10:09:09 PM12/29/09
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On Tue, Dec 29, 2009 at 9:07 PM, wulfdesign wrote:
> I can't currently use OpenSCAD but will look at the .stl file and see
> if I can convert it to STEP. in Rhino3D.
>
> I've got a couple of ideas I'd like to try out on the conversion
> process (by hand).
> this is as good a file to try it with as any.

Neat, thanks. You might have to do it by hand, yeah. :-( I'd like to
hear of your progress or what steps you have to take, etc. You're my
hero!

Cathal Garvey

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Dec 29, 2009, 10:21:15 PM12/29/09
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I'm really delighted to see so much interest in the project! Please do document any further work here or on Thingiverse. I feel like this is my first proper open-source release, it's interesting to think what might become of it!

Alec Nielsen

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Dec 29, 2009, 10:33:00 PM12/29/09
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On Tue, Dec 29, 2009 at 6:20 PM, Cathal Garvey <cathal...@gmail.com> wrote:
> A demo of Dremelfuge is now up on Youtube:
> http://www.youtube.com/watch?v=86WnXeTZO_Y

I love this! It's high time I got my hands on a 3D printer. Excellent work, man.

Alec

Cathal Garvey

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Dec 29, 2009, 10:38:19 PM12/29/09
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Thanks! :) I gotta say, it wouldn't have happened if I didn't have a Makerbot.

Tito Jankowski

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Dec 30, 2009, 4:37:32 AM12/30/09
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Very slick. Good work, Cathal, great video too!

Tito

On Wed, Dec 30, 2009 at 9:08 AM, Cathal Garvey <cathal...@gmail.com> wrote:
> Thanks! :) I gotta say, it wouldn't have happened if I didn't have a
> Makerbot.
>

Cathal Garvey

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Dec 30, 2009, 8:16:45 AM12/30/09
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Thanks Tito!
Tested it with bacteria and mammal cells today:
www.twitpic.com/vvau6
www.twitpic.com/vvb2l

Both pellet just fine! :D

On Dec 30, 2009 9:37 AM, "Tito Jankowski" <titoja...@gmail.com> wrote:

Very slick. Good work, Cathal, great video too!

Tito

On Wed, Dec 30, 2009 at 9:08 AM, Cathal Garvey <cathal...@gmail.com> wrote: > Thanks! :) I gotta...

> -- > > You received this message because you are subscribed to the Google Groups > "DIYbio" group....

Tito Jankowski

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Dec 31, 2009, 3:24:06 AM12/31/09
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Cathal Garvey

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Dec 31, 2009, 8:20:08 AM12/31/09
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Awesome! Thanks!
Next on the list: Vacuum Manifold! ;)

Cathal Garvey

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Dec 31, 2009, 8:26:25 AM12/31/09
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Whoops, just looked at the Shapeways shop and realised the Recessed Edition has been missing for perhaps 24h.. It's now back up. Apologies in case anyone was confused by the lack of a Dremel-compatible Dremelfuge for a while there.

Tom Randall

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Dec 31, 2009, 8:09:35 PM12/31/09
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This looks extraordinarily useful. My current Microfuge for quick
spins is dying and this looks like a perfect replacement. What is the
difference between the Recessed Edition and the Chuck Edition shown at
Shapeways? I will definitely get one for spinning 1.5 ml Eppendorfs.
Will definitely not use this for "ornamental" purposes only.

> Please excuse my eccentric appearance

You appear completely normal, I was expecting nose rings and tattoos
from the comment.

wulfdesign

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Jan 1, 2010, 12:41:15 AM1/1/10
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think the only difference it that the Recessed Edition you use a metal
Dremel disc attachment tool.
and the Chuck Edition has a printed plastic Chuck.

I was thinking that the metal Dremel chuck would be stronger but
it appears that the Eppendorfs fail way before any DremelFuge parts
give out.

-Larry

Cathal Garvey

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Jan 1, 2010, 9:39:02 AM1/1/10
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Correct on all counts! I made two editions to allow people to pick one to suit their available tools. The recessed edition is designed specifically for the dremel cutting-disc holder, whereas the chuck edition can be used with any drill, router or machine that can grip it.

I can design other recesses for different tools on request, too.

I hope I'll get to hear about these non-ornamental uses, and that it serves your needs well! Always play it safe though. Enjoy it! :)

On Jan 1, 2010 5:41 AM, "wulfdesign" <wulfd...@gmail.com> wrote:

think the only difference it that the Recessed Edition you use a metal
Dremel disc attachment tool.
and the Chuck Edition has a printed plastic Chuck.

I was thinking that the metal Dremel chuck would be stronger but
it appears that the Eppendorfs fail way before any DremelFuge parts
give out.

-Larry

On Dec 31, 5:09 pm, Tom Randall <tarand...@gmail.com> wrote: > This looks extraordinarily useful. M...

Nathan McCorkle

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Jan 1, 2010, 2:20:35 PM1/1/10
to diy...@googlegroups.com, Christopher Tomkins-Tinch
What happened to the failed microtubes??? So can we use this to do ultracentrifugation stuff with caesium chloride gradients and separating proteins, etc?? I hear DIY enzyme production and purification!


That article says it requires 100,000 x G but the dremel can provide half of that... so maybe we can increase the rotor radius, or still do some decent protein purifications if we use enzymes linked to differing amounts of junk aminos to alter the density significantly between unique enzymes.

There is no reason this should be considered an ornament as long as there is a protection bowl around the device, unless of course we start finding that the device itself is self-destructing.

-Nate

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Tom Randall

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Jan 1, 2010, 7:52:09 PM1/1/10
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CsCl gradients, at least for DNA, usually require hours of spin time,
vacuums and more serious tubes than microfuge type eppendorfs. The
limitation there may be the power drill or other device doing the work
of generating the rpms and how long it would last and the heat it
might generate.

On Jan 1, 2:20 pm, Nathan McCorkle <nmz...@gmail.com> wrote:
> What happened to the failed microtubes??? So can we use this to do
> ultracentrifugation stuff with caesium chloride gradients and separating
> proteins, etc?? I hear DIY enzyme production and purification!
>
> http://en.wikipedia.org/wiki/Isopycnic_centrifugation
>
> That article says it requires 100,000 x G but the dremel can provide half of
> that... so maybe we can increase the rotor radius, or still do some decent
> protein purifications if we use enzymes linked to differing amounts of junk
> aminos to alter the density significantly between unique enzymes.
>
> There is no reason this should be considered an ornament as long as there is
> a protection bowl around the device, unless of course we start finding that
> the device itself is self-destructing.
>
> -Nate
>

> On Tue, Dec 29, 2009 at 7:05 PM, Cathal Garvey <cathalgar...@gmail.com>wrote:
>
>
>
> > Quick update: Dremelfuge works comfortably at 10krpm. It can exert a
> > maximum RCF of about 52000g, more than enough to shatter microcentrifuge
> > tubes as it turns out. Dremelfuge itself is completely undamaged after this
> > abuse.
>
> > This means that, when used within the speed envelope corresponding to
> > normal lab forces (no faster than 16,680 rpm, or 14k RCF), Dremelfuge should
> > be perfect for any DIYbio applications. It even evinced a robust disregard
> > for unbalanced tubes.
>
> > As always, for reasons of liability I do not endorse use of Dremelfuge as
> > anything but an Ornament.
>
> > Video forthcoming.
>

> > On Dec 29, 2009 9:52 PM, "Cathal Garvey" <cathalgar...@gmail.com> wrote:
>
> > Well, the design is currently made in OpenSCAD, which doesn't support
> > outputs besides .stl and .off. OpenSCAD and Sketchup are my suites of choice
> > and I haven't worked with Solids before.
>
> > At some point I may learn another language for solid designing and re:make
> > it, but at the moment I'm occupying my time testing the current version on a
> > Dremel. If you're handy with a modeller, I invite you to replicate it
> > though? Provided I could get a copy of the resulting source/model for
> > Thingiverse, in case others need a solid too.
>
> >  --
> > You received this message because you are subscribed to the Google Groups
> > "DIYbio" group.
> > To post to this group, send email to diy...@googlegroups.com.
> > To unsubscribe from this group, send email to

> > diybio+un...@googlegroups.com<diybio%2Bunsu...@googlegroups.com>

Nathan McCorkle

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Jan 1, 2010, 7:56:32 PM1/1/10
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On Fri, Jan 1, 2010 at 7:52 PM, Tom Randall <tara...@gmail.com> wrote:
CsCl gradients, at least for DNA, usually require hours of spin time,
vacuums and more serious tubes than microfuge type eppendorfs. The
limitation there may be the power drill or other device doing the work
of generating the rpms and how long it would last and the heat it
might generate.


So we use pneumatic tools instead
 
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Cathal Garvey

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Jan 2, 2010, 9:55:36 AM1/2/10
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Hi Nathan,
Although the device itself is able to survive 33,000 rpm admirably, the Eppies were less fortunate. Above the speeds you'd use on a normal centrifuge, it seems the plastic isn't that strong, and the eppies shattered and flew off the rotor. So, unless you want to experiment with tougher glass eppies (read DON'T), this isn't really intended for anything a normal microcentrifuge could do.

And yes, if you decide to use this (at your own risk), you could do protein or dna purification, but probably only with affinity columns suited for microcentrifuge work. I don't like to think of people going up to the full 52,000g or higher with this!

I can only ever endorse this for ornamental use, because it'd be very easy for someone to hurt themselves if they didn't take suitable safety precautions. I don't want to be responsible for personal harm, so I encourage anyone thinking of using this for other purposes to wear goggles, spin in a pot, etc etc. Just be really careful!

Meredith L. Patterson

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Jan 2, 2010, 11:40:12 AM1/2/10
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On Sat, Jan 2, 2010 at 3:55 PM, Cathal Garvey <cathal...@gmail.com> wrote:
> And yes, if you decide to use this (at your own risk), you could do protein
> or dna purification, but probably only with affinity columns suited for
> microcentrifuge work.

I have a bunch of plasmid miniprep columns that fit into 2mL eppies,
actually, so I've just ordered a Dremelfuge in order to give that a
try. It'll be easier than finding a US->EU transformer that can handle
the current my microcentrifuge takes, that's for sure!

> wear goggles, spin in a pot, etc etc.

Dremel makes a rather nice drill press attachment which I'm going to
try with this, as it holds the tool in the correct position and is
very stable. (I've successfully drilled clean holes through 1/4" steel
with it, so it definitely keeps the vibration down.)

Cheers,
--mlp

Derek

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Jan 2, 2010, 12:53:02 PM1/2/10
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I follow the competent cells protocol here:
http://openwetware.org/wiki/TOP10_chemically_competent_cells

This requires spinning down fairly large batches in the main lab's
refrigerated centrifuge, which I don't always have access to. In
trying to scale things down to be done at my bench microfuge, the
volumes work out to be able to prepare about one transformation's
worth of competent cells in an epi. Good enough, but the cells are
sensitive enough that most of them die during the unrefrigerated spin.

Dremelfuge is interesting in that it seems like by filling the bottom
of the metal bowl I'd be spinning in with dry ice that I might be able
to keep the ambient temperature low enough to keep my cells alive.

Of course, I'd love to be able to spin larger tubes to prepare more
than one transformation's worth at a time.

1) does the dry ice in the bowl scheme sound reasonable?
2) does it sound feasible to scale the dremelfuge up to handle 15ml
centrifuge tubes rather than epi's? (I think the answer here is no, at
least not without a really big metal bowl!)
3) any other ways around this problem, for instance are there decent
competency protocols that aren't as heat sensitive that I might not
know about? (without going to electroporation or something else that I
don't have sufficient equipment for.)

Thanks for any ideas!

--Derek

On Jan 2, 4:40 pm, "Meredith L. Patterson" <clonea...@gmail.com>
wrote:

Derek

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Jan 2, 2010, 1:12:51 PM1/2/10
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Oh shoot, sorry, I thought that by editing the title I was forking the
discussion, not changing it for the whole thread (changing it back
now...)

Cathal Garvey

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Jan 2, 2010, 1:16:49 PM1/2/10
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Cool! Let me know how it works! Bear in mind the latest design has a slightly bigger rotary distance, and with 2ml tubes you'll have to re-derive your intended rpms for the gees you need.

By way of reminder:
Gees = rpm^2 * rotary radius in cms * 0.00001118

Hope it doesn't take too long!

On Jan 2, 2010 4:40 PM, "Meredith L. Patterson" <clon...@gmail.com> wrote:

On Sat, Jan 2, 2010 at 3:55 PM, Cathal Garvey <cathal...@gmail.com> wrote: > And yes, if you deci...

I have a bunch of plasmid miniprep columns that fit into 2mL eppies,
actually, so I've just ordered a Dremelfuge in order to give that a
try. It'll be easier than finding a US->EU transformer that can handle
the current my microcentrifuge takes, that's for sure!

> wear goggles, spin in a pot, etc etc.

Dremel makes a rather nice drill press attachment which I'm going to
try with this, as it holds the tool in the correct position and is
very stable. (I've successfully drilled clean holes through 1/4" steel
with it, so it definitely keeps the vibration down.)

Cheers,
--mlp

-- You received this message because you are subscribed to the Google Groups "DIYbio" group. To po...

Cathal Garvey

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Jan 2, 2010, 3:41:11 PM1/2/10
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No, you forked it alright!
My thoughts:

- Eppies are spun "by the neck", which is part of the reason I could make the rotor so small. The rotor pretty much has to be small if you want to spin it by dremel, so it'd have to be a drill-fuge for anything bigger. Falcon tubes don't have a "neck", just a lid that'd pop off easily. You have to seat them on their ends when spinning.

- So to spin Falcon tubes, you'll need to have a bucket-style centrifuge, which probably means printing very sturdy, low-centre-of-gravity buckets, plus a pivot piece to seat the buckets in, plus a rotor which swings the pivot pieces. You'd probably use lengths of metal to connect the rotor to the pivots, maybe standard pieces like contraptor or makerbeams when they become available.

- This means more parts and a wider rotary distance, with moving parts as part of the rotary design. More parts means more points of potential failure.

So I'd say, you could certainly do this with a printed centrifuge, but it would want to be for low gees because the odds of failure are much higher, and the mass of the ejecta in the case of a failure are much much higher also. I can't remember offhand, but I reckon you'd need high gees for preparing competent cells. I'd reckon a multi-part centrifuge would be more suited to mammal cells that call for lower gees.

Also, you'd want a drill/machine you can slowly ramp up, because with a multi-part bucket rotor you'll need to start slow until the buckets have spun outward properly.

If you want a hand designing such a multi-part centrifuge, I'd be happy to help! But I don't foresee it being safe.

I'm planning to use my dremelfuge for prepping competent cells, by spinning it in a cold room, fridge or freezer. Your idea to use dry ice is pretty neat, I'd love to see your results if you do it! Bear in mind that when spinning, dremelfuge itself and the dremel you attach it to produce strong air currents, so it'll blow away the cold air unless it's contained somehow. Perhaps if you were to cut a dremel-neck-sized hole in the lid of a pot you could have a fairly closed cavity in which to spin, which would enable benchtop applications.

Cory Tobin

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Jan 2, 2010, 3:50:01 PM1/2/10
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> I can't remember offhand, but I reckon you'd need high gees for
> preparing competent cells.

The protocol I use for spinning down competent cells is: 10 minutes, 4C, 2700g.

-Cory

Cathal Garvey

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Jan 2, 2010, 3:58:06 PM1/2/10
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Hm, you wouldn't need that much speed with a larger rotary distance then. Still, any ejecta is going to be travelling fast enough to pack a dangerous wallop.
15ml ~ 15grams. 15grams * 2700g ~ 40.5kg.

Allowing for 50% speed decline due to tumble or wind resistance, that could still be 20kg to the head.

2010/1/2 Cory Tobin <cory....@gmail.com>
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Cathal Garvey

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Jan 18, 2010, 8:22:33 PM1/18/10
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Update for all interested in this and similar designs:

I received my own Dremelfuge today, and I am very satisfied with the quality of the printing. So much so in fact that I am concerned that the error tolerances I had included in the design may have slightly compromised the tightness of the Eppie Fit. I have immediately compensated for this, and I'm pretty sure the next generation of Dremelfuges will be far more to my satisfaction.

I am aware that Meredith ordered a Dremelfuge, and one other person so far. If either find that their Dremelfuge doesn't work as intended, please contact me and we'll sort it out! The last thing I'd want is an unsatisfied customer!

If people would like to follow developments in all of this, twitter would be the best way: @labsfromfabs. I'll be sharing my progress there.

All the best,
Cathal

Nathan McCorkle

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Jan 18, 2010, 8:30:39 PM1/18/10
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The innovation center at school has a makerbot, I want to make a
dremelfuge that is angled so the pellet forms along the side so I can
pipet out all the fluid without taking any cells/etc...

How do I draw stuff for the makerbot? And could I take your design and
hack it somehow? (would you let me)?

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Cathal Garvey

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Jan 18, 2010, 8:36:46 PM1/18/10
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Any modelling suite that exports STL files can be used by Makerbots. I chose OpenSCAD, as it is an excellent way to produce easily modified and parameterised designs. Some knowledge of coding required, though.

You are very welcome to hack the design, as it's licensed under a Creative Commons Attribution, Sharealike, Noncommercial License! Please do upload pictures and modified source files to Thingiverse if you do though, I'd love to see it.

Just a note of caution, the force in dremelfuge is perpendicular to the lip of the eppies, this is how it achieves the grip needed to spin. You'd need a very different edge on the rotor to grip eppies sideways safely.

Tom Randall

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Jan 19, 2010, 9:10:32 AM1/19/10
to DIYbio

On Jan 18, 8:22 pm, Cathal Garvey <cathalgar...@gmail.com> wrote:
> Update for all interested in this and similar designs:
>
> I received my own Dremelfuge today, and I am very satisfied with the quality
> of the printing. So much so in fact that I am concerned that the error
> tolerances I had included in the design may have slightly compromised the
> tightness of the Eppie Fit. I have immediately compensated for this, and I'm
> pretty sure the next generation of Dremelfuges will be far more to my
> satisfaction.
>
> I am aware that Meredith ordered a Dremelfuge, and one other person so far.
> If either find that their Dremelfuge doesn't work as intended, please
> contact me and we'll sort it out! The last thing I'd want is an unsatisfied
> customer!
>

Mine came on Monday, the fit looks pretty good, at least with the
eppendorfs I have, will try some spins tonight.
Tom

Cathal Garvey

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Jan 19, 2010, 9:57:56 AM1/19/10
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Take care! And please share your results. Don't hesitate to let me know if you have any issues.

On Jan 19, 2010 2:10 PM, "Tom Randall" <tara...@gmail.com> wrote:

On Jan 18, 8:22 pm, Cathal Garvey <cathalgar...@gmail.com> wrote: > Update for all interested in t...

Mine came on Monday, the fit looks pretty good, at least with the
eppendorfs I have, will try some spins tonight.
Tom

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Tom Randall

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Jan 19, 2010, 9:03:50 PM1/19/10
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Seems to work well, tested with 6 eppendorfs each loaded with 1 ml H2O
to test and it was ok. My current setup (see http://sites.google.com/site/roningenetics/pictures
and go to centrifuges picture) only goes 2000 rpm with the drill I
have, so it is probably only good for spinning down cells and simple
things, but eventually I will get hold of a drill that goes 10K or so
and test it with that, which should be good for phenol/CHCl3
extractions.

On Jan 19, 9:57 am, Cathal Garvey <cathalgar...@gmail.com> wrote:
> Take care! And please share your results. Don't hesitate to let me know if
> you have any issues.
>

> On Jan 19, 2010 2:10 PM, "Tom Randall" <tarand...@gmail.com> wrote:
>
> On Jan 18, 8:22 pm, Cathal Garvey <cathalgar...@gmail.com> wrote: > Update
> for all interested in t...
> Mine came on Monday, the fit looks pretty good, at least with the
> eppendorfs I have, will try some spins tonight.
> Tom
>
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Cathal Garvey

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Jan 20, 2010, 4:41:19 AM1/20/10
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I'm delighted to hear it's passed testing at 2krpm, and I'll be crossing my fingers for 10k also! Be thorough in testing before you work with Phenol/Chloroform, neither are much-desired projectiles! :)

2010/1/20 Tom Randall <tara...@gmail.com>
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Cathal Garvey

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Jan 20, 2010, 4:42:49 AM1/20/10
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Also, great to see one in the wild on your site! Thanks!

JonathanCline

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Mar 1, 2010, 11:21:00 PM3/1/10
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On Dec 29 2009, 6:58 am, Cathal Garvey <cathalgar...@gmail.com> wrote:
> Dremelfuge is a rotor designed to fit standard lab microcentrifuge tubes and
> miniprep/purification columns, to be spun by either a powerdrill or other
> chuck-loading machine or by a popular rotary tool.


Added to FAQ!

http://openwetware.org/wiki/DIYbio/FAQ/Projects#Homebrew_Centrifuge


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Cathal Garvey

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Mar 2, 2010, 3:56:28 AM3/2/10
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Cool, thanks! :)

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Phil

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Mar 2, 2010, 3:32:46 PM3/2/10
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I would really like a set of PCR tube adapters made from this printed
plastic, and sold online. I can buy adapters to spin .2ml or .5ml
tubes in an Eppendorf meant for 1.5ml tubes, but they cost $10
apiece! That's a lot to pay for a little piece of plastic. And there
are no .5ml to .2ml adapters that I can find anywhere. I have a .5ml
rotor that I'd like to use to spin .2ml PCR tubes.

Brian Degger

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Mar 2, 2010, 5:13:00 PM3/2/10
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i used to use 1.5ml PCR tubes with their lits cut off to spin single
0.5ml tubes, they nested well,
not sure how well the 0.2ml tubes nest as I didn't have any to try.

Cathal Garvey

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Mar 2, 2010, 5:28:48 PM3/2/10
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I find my PCR tubes spin well in 0.5ml tubes, and those in 1.5ml tubes. Should work fine!

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Nathan McCorkle

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Jan 31, 2013, 2:14:10 AM1/31/13
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On Tue, Mar 2, 2010 at 2:28 PM, Cathal Garvey wrote:
> I find my PCR tubes spin well in 0.5ml tubes, and those in 1.5ml tubes.
> Should work fine!

On 3/2/10 Brian Degger wrote
> i used to use 1.5ml PCR tubes with their lits cut off to spin single
> 0.5ml tubes, they nested well,
> not sure how well the 0.2ml tubes nest as I didn't have any to try.

So did either of you ever try 0.2mL tubes? I need a centrifuge, and I
have a dremel...

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Cathal Garvey (Phone)

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Jan 31, 2013, 5:09:49 AM1/31/13
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Yea, inside larger tubes. Just sit 0.2 inside 0.5 inside 1.5ml tubes, the fit is usually quite snug.
Sent from my Android phone with K-9 Mail. Please excuse my brevity.

Larry James

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Jan 31, 2013, 3:30:44 PM1/31/13
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oh,
thats smart,

duh.

thought would have to modify & print up a custom one for different sizes.

sometimes I wonder ;)

L

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Nathan McCorkle

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Jan 31, 2013, 4:06:15 PM1/31/13
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On Thu, Jan 31, 2013 at 12:30 PM, Larry James <wulfd...@gmail.com> wrote:
> oh,
> thats smart,
>
> duh.
>
> thought would have to modify & print up a custom one for different sizes.
>
> sometimes I wonder ;)

Well being that I don't have any tubes now, it is probably cheaper to
just modify the design and print different sized heads.

Cathal, would I just have to change the diameter of the hole?

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Cathal Garvey (Phone)

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Jan 31, 2013, 5:30:59 PM1/31/13
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IIRC you'd need to input the diameter of the tube just under the lip, and the additional mms added by the lip. Honestly I wouldn't recommend an open ended design for pcr tubes though, they are so small that errors in printing due to dodgy skeining or alignment could easily lead to ejection.

Possibly if you make the rim thickness big enough it'll enclose the tubes entirely, I don't recall offhand how closely the cutouts matched the shape of a tube. Play around in openscad I guess!

B SM

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Aug 10, 2013, 10:47:26 AM8/10/13
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Hello,
My question pertains the "chuck edition" that works with drills as stated in http://www.shapeways.com. Would any standard drill do? do we need any particular bit/adapter? What is the expected time for shipping? We are looking for an affordable option for an AP Biology course, as our school does not have the resources to purchase a microcentrifuge.
thanks



On Tuesday, December 29, 2009 8:58:07 AM UTC-6, Cathal Garvey wrote:

Dremelfuge is a rotor designed to fit standard lab microcentrifuge tubes and miniprep/purification columns, to be spun by either a powerdrill or other chuck-loading machine or by a popular rotary tool.

Dremelfuge features an easy click-in loading system which holds tubes parallel to the plane of rotation for optimum pelleting and delivery of force.

Intended basic applications of Dremelfuge include column purification (tested to work with miniprep columns) and bacterial/cell debris pelleting (under testing). With standard microcentrifuge tubes, the average rotary distance is 4cms.

Dremelfuge is open-source hardware. Source files are available on Thingiverse, linked from the items on Shapeways. The Creative Commons license used entitles copying, sharing and remixing for any non commercial purpose. Please consider that professional printing services qualify as commercial use.

Two editions of Dremelfuge are available for purchase at
www.shapeways.com/shops/labsfromfabs

One has an axle which can be gripped in a chuck fitting. The other is intended for fitting to a cutting-disc-holder for rotary tools such as a dremel*.

Please share your results and experiences on Thingiverse!

Note: Although I have shown Dremelfuge to work at 3000rpm/400rcf, and intend shortly to test at dramatically higher speeds on a low-cost rotary tool, I don't endorse or recommend use of Dremelfuge as anything but an ornament. Dremelfuge poses a serious safety hazard if used for any other purpose. Please take every precaution if you decide to take such risks. Further advice on Thingiverse.

*Design assumes a disc holder diameter of 3mm and a screw diameter of 2mm. Other designs available on request.

Larry James

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Aug 11, 2013, 3:51:18 PM8/11/13
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you'll need something with more rpm and variable speed... a dremel like tool.

be sure to follow safety instruction as well to keep from loosing important body parts that may be useful later.

L

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Christopher Pendlebury

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Aug 14, 2013, 5:27:14 PM8/14/13
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The rotor needs some design tweaking to hold the tubes in place. 

Also whenever you spin it do it in a steel pot or bowl. 

I tried it with two eppies with 500ul milk. I found that my eppies shot out of the rotor, ricocheted off the bowl and remain unaccounted for.

The rotor itself holds up fine when spun. It can take as much spin as a dremel can throw at it.

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Cathal Garvey

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Aug 14, 2013, 6:13:20 PM8/14/13
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Hi Christopher,
Dismayed to hear about your experiences, though not exactly surprised.

I'd love to hear more about the precise diameters of your tubes just
under the rim, and of the rim itself? Also, was this a self-print, or a
Shapeways print? If self-print, what are the diameters of the channels
the tubes sit into, and the diameters of the "lip-shelves" just inside
those channels that the tubes rest upon?

I'm assuming you're not using the earliest model, which simply had
conical shaped channels tubes were clicked into; those reliably ejected
above the second setting on my dremel! :)
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Avery louie

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Aug 14, 2013, 10:28:57 PM8/14/13
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I took some measurements of the tubes in my lab.


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