How long should it take for the build platform to heat?

[Moby Disk]

How long should it take for the HBP on a Makerbot Replicator to get from room temperature (20 degrees c) to 110 degrees C? 

Mine seems to take about 15 minutes.  Is that normal?  Probably 10 minutes is spent going from 100 to 110.  Yet it only takes 20 seconds to cool down from 110 to 100.

During the warm-up time, my printer extrudes a few inches of ABS, which I have to reach in and chop off before the build starts or it carries this bead over to the print and develops into a blob.  About half my prints are aborted because of this problem.  If I fail to get it in time, I cancel the print and try again - which means I wait another 10 minutes.  Since I tend to print small objects, I'm spending more time in warm up than in actual printing.  I'm hoping that everyone here goes "Really?  Mine heats in under 5 minutes!" which would mean there is something I can look into to fix the problem.

[Dan Ujvari]

Yeah, it takes awhile for that bed to warm up.  I hope you're overstating the length of time between 100 and 110.  Mine takes about 10 to 15 minutes (never timed it), but it seems to heat at a fairly constant rate until it reaches the target temperature.  Maybe the thermistor output on your machine isn't linear?  

I typically tell the bot to preheat as soon as a job is done, so it doesn't cool down while I prepare for the next print.  If I leave the machine, I'm in the same boat... waiting for it to heat. ;-)  But that's better than it cooking away and we forget about it. 

Yeah, I get that little filament ooze too, but mine usually doesn't get to the print.  It either pops off when the print starts, or it gets caught up in that starting blob the extruder puts down just before it takes off to print the object.  Rarely, it makes it to the object and becomes a whisker hanging off the thing, but that's 1 time in 8 or 10.

--
You received this message because you are subscribed to the Google Groups "MakerBot Operators" group.
To unsubscribe from this group and stop receiving emails from it, send an email to makerbot+u...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
 
 

[brain...@comcast.net]

My old one took 8 minutes in a cold garage.  See here for thermal images: https://groups.google.com/forum/?fromgroups=#!topic/makerbot/1bhigvIOTNo
You may have a problem with your connector plug, or your screws may not be tight enough.  They should hold the aluminum against the board, but be loose enough to allow expansion.

Bob

[66tbird]

7 to 9 seconds per degree when I have a good connection on the far left pin of the HBP connector.  Any more and I add conductive grease to only that pin. (carefully)

I use an early version of Artic Silver CPU thermal compound that was made of fine silver and is extremely conductive (and messy)  The new stuff is not conductive.

[MacGyver]

This is on a Thing-O-Matic so it might not be your problem...

I found after replacing the fan on my extruder my HBP would take a very long time to heat up.  I discovered that the fan shroud I put on + the new fan were actively cooling my platform too much.  I ended up putting a piece of electrical tape over part of the fan and it's been heating up just fine since.  It usually takes less than 10 minutes, however, the HBP is much smaller on a TOM.

[Gary Crowell]

8:20.  I have replaced the board connector with an off-board connector.

--

You received this message because you are subscribed to the Google Groups "MakerBot Operators" group.
To unsubscribe from this group and stop receiving emails from it, send an email to makerbot+u...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
 
 

--
----------------------------------------------
Gary A. Crowell Sr., P.E., CID+

Linkedin  Elance  KE7FIZ

[CKChavez]

Hi Moby,

My Rep1 reaches target temp of 110c in 5 minutes 3 seconds followed by my extruder head target temp 230c in 1 Minute 46 seconds.

Note that early on when I first received my Rep1, I had removed the aluminum plate and put a layer of thermal compound paste (non-conductive) in between the actual HBP and aluminum plate and smeared it around evenly, then reattached. This sped up my time to the target heat temp substantially. My HBP gets to my target temperature quickly and also now evenly heats on all areas of the aluminum surface with no varying hot or cold spots.

Target temp is set at 110c (note that using an IR Thermometer to measure the surface of the aluminum plate, the IR thermometer reads at 100c on all areas of the plate.)

Hope this info helps.

[Moby Disk]

Thanks everyone for the timings.  I'm glad to know I'm not really that much of an outlier.  I finally timed my own printer: It took 10 minutes to go from 16 degrees to 110.  The last 2 degrees took 1.5 minutes.

Is there a calibration for the temperature sensors?  It isn't 16 degrees in my house right now, closer to 18 or 19.  I also notice that at power-on the extruders read a different temperature from the build platform.  Maybe I'll ask that in another thread.

Thanks!

[RocketGuy]

On Tuesday, April 23, 2013 1:02:35 PM UTC-7, CKChavez wrote:

Hi Moby,

My Rep1 reaches target temp of 110c in 5 minutes 3 seconds followed by my extruder head target temp 230c in 1 Minute 46 seconds.

Holy Carp!  That's fantastic!

 

Note that early on when I first received my Rep1, I had removed the aluminum plate and put a layer of thermal compound paste (non-conductive) in between the actual HBP and aluminum plate and smeared it around evenly, then reattached. This sped up my time to the target heat temp substantially. 

Can you advise which paste you're using?  I'm in the middle of upgrades and it's a perfect time for me to do this as well.   

[Matthew Marlowe]

Keep in mind what the goal is when pre-heating the build plate -- the
goal is not just reaching a set temperature but also a) warming up the
entire build environment and b) ensuring that however your build plate
deforms itself, that the process is complete and will not continue to
significantly change after you press the print button.

For me, this is about 20-25 minutes on my replicator1 depending on
ambient temperature. I usually re-home the build plate so that the
unused extruder is just above the plate (print with right extruder,
monitor temp of the idle extruder). I have my active extruder
pre-heat at 160 degree temp (not at the default 230) which is just
good enough to make it worthwhile to do w/o causing too much extra
filament to come out, and usually by the time the idle extruder turns
its fan on the entire environment is fully heated.... If I need to,
I'll quickly pull off any plastic that might have come out of the
active nozzle before starting the print.

[MBuser]

It looks like enclosure temp control is as important to ABS as plate temp. A long warm-up and cool-down period seem ideal. I guess this can can be programmed into a profile or slice?

[S Scherrer]

Tend to agree on this... Have been printing all week-edn quite well and no issues with ABS sticking to bed,,, yet I expereinced the following yesterday :

 - if I switch on everything and tried to print as soon as I could : I could start printing within 10mn (did not measure, but bed and extruder would take about this), yet I would have issue with ABS not sticking well on first layer. Considering I had printed very weell for thr weekend I knew my levels, and settings are correct...

 - So I patiently waited again exact same settings after another 10-15mn, then it sticked pretty well

 

In both cases the bed had reached target temp of 110 , yet the inside environment air was not sufficiently warmed up (should I had that I have NOT the enclosure lid and I';m using a towel on top...)

 

My conclusion from above is that YES the enclosure environment needs to warm up too and that can take longer than just heating the build and extruder... So from now on. I will make sure to warm up 25mn the enclosure and THEN start my build. It probably is down to the lid missing and the towel not ideal (this said., works beautifull once warmed up...).

 

Stephane

[66tbird]

For ABS the chamber temp is very important to get warp free prints. I print in a very warm barn and have fully enclosed my rep1 for two reasons. One is dust control, the other is chamber temperature. I have a top cover, top corner covers, inner chamber corner blocks, lcd cover, and magnetic mount side panels.  These summer months are my large print times because my ambient temp are 110-125F in the barn. When properly leveled, which for me is 0.12mm or .005'', and in a draft-less warm 70C+ chamber I can print anything without worry of warp-age.  There are times when my not-in-use extruder temp is 85C or more. I don't worry about the steppers. In gerenal those are cheap if they fail. I've got another cnc rig that gets the steppers so hot the will sizzle spit, and it's got lots of time on it. 8hr/day for five years.

[MBuser]

Sounds like it really is chamber temp that is important. Maybe the chamber could have a controlled cool-down via slowly lower the plate temp.