1 Topic by rickq (edited by rickq 2017-03-03 23:52:34)

  • rickq
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Topic: Double bed heater

A while back I posted pics of my all metal gantry and extruder hack:
http://www.soliforum.com/topic/15488/my … metal-sd3/

In that post I was annoyed that that the new MK2 PCB bed running at 24V was no faster heating than the original equipment 12V silicone pad.

Solution:
Short answer:  Connect the MK2 and the silicone pad (I left it on as insulation) in series and run them at 24V.  Heats up in 7min.


Longer answer: The MK2 bed measured 6ohm across the 24V leads and 3ohm across the 12V leads (duh).  The silicone pad measured 2ohms.  Wired the MK2 for 12V and connected it in series with the silicone pad. 3+2=5ohms.

20% power increase form 96W to 115W.  Current increases from 4A to ~5A.  That is okay for me since the the 24V supply is good for 15A and I am running it through a 30A solid state relay controlled directly from the original bed heater MOSFET on the Sanguinolulu.

Maybe should run the bed PID routine, but the glass does a good job of damping the power bumps.

Did I mention it heats up in 7min.

2 Reply by heartless

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Re: Double bed heater

better answer: get one of these: https://www.printitindustries.com/produ … -8-heatbed

SD4 #1 & #2 - Lawsy carriages, E3D v6, Rumba controller board, mirror bed plate, X motor fan, upgraded PSU & Mica bed heater
SD4 #3 - in the works ~ Folgertech FT-5, rev 1
Printit Industries Beta Tester - Horizon H1

3 Reply by rickq (edited by rickq 2017-03-04 19:00:39)

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Re: Double bed heater

Agreed - ish.

I had already purchased the MK2 and the rest came out of my "junk" bins.  So I paid around $13, plus the cost of storage in a plastic tote in my garage for who knows how long.

I am not a hoarder.  I say this to anyone who is around when I re-purpose someone's junk.

So, if over the years that the MK2 has existed anyone here has installed one and would like a 50 or 60% power bump for a little wiring and no tear down:  For the cost of a $9 relay and a $20 power supply ...

Not advocating, just information.

4 Reply by heartless (edited by heartless 2017-03-04 19:14:54)

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Re: Double bed heater

i have had both the silicone pads (stock SD4) and MK2 beds - altho I have never tried running both at once...

the Hale is far and away, leaps and bounds better. Even on a 3/16" thick aluminum plate with 3mm thick mirror tile on top of that, it takes Less than 10 mins to get to operating temp... I turn the bed on, and while it is heating, I will load my model, tinker with slicer settings, & slice - by the time I decide the model is ready for printing, the bed is hot and ready to go - and the heat is even across the bed, no hot spots, no cold spots - i can run stuff right out to the edge of the bed with no problems.

Oh, and i don't hoard either, wink lol  *shoves the tote with excess parts further under the desk with her toe*

SD4 #1 & #2 - Lawsy carriages, E3D v6, Rumba controller board, mirror bed plate, X motor fan, upgraded PSU & Mica bed heater
SD4 #3 - in the works ~ Folgertech FT-5, rev 1
Printit Industries Beta Tester - Horizon H1

5 Reply by Ski52

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Re: Double bed heater

I've heard a lot of good things about the Hale pad, but I use a SD2 - 150mm/6in bed.  Azerate had mentioned in the past that he had hoped to develop a 6' version.  I use an aftermarket silicone pad I bought from Azerate after my aftermarket one quit.  With a Supernight PS (12V), SSR and a silicone pad, I heat to 97C in 3 min or just under.

Ender 3 Pro

6 Reply by carl_m1968

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Re: Double bed heater

Just out of curiosity, why is everyone so worried about heatup times. I mean there has to be many things you do while waiting. Even work on the next project. Like heartless said, you can get the file ready while it is heating. I am just curious as mine take about ten minutes to reach 65, and that is no real issue to me as I can do other things while it heats so no time is lost.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

7 Reply by rickq

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Re: Double bed heater

10 min?  That would have been peachy.  But 22min to get to 100°C was tedious.

And my model has been sliced by then anyway.  For me slicing is part of the iterative design/modeling process.  I have never had the occasion to print a part I did not model. When I boot the printer I am ready to print.

Regardless, this thread was about an economical way to improve performance by utilizing some assets that are already on the printer that may have been disconnected due to a hack.  Not time management, which is not a hack.

No worries.  Next project, redo the crappy enclosure I made 4 years ago.  I have some 1/4 inch polycarb that I scavanged from a fume hood sitting next to a dumptser behind the neighboring prosthetics company (a few Benjamins retail).

I am not a hoarder.