"Dauerdruckplatte" PEI coated Aluminum bed

[Polygonhell]

This is something I came across a few weeks ago on the reprap forum, apparently they are quite popular in Germany.
Basically it's an aluminum tooling plate (usually 6mm), with a thin coating of PEI bonded to it. It is not adhered to the surface, but some sort of a molecular bond.

I haven't been able to source one in the US and my home shop isn't up to manufacturing one.
I'm wondering if anyone here has tried one? or is up to making one and reporting?
I'm interested in how the surface holds up, the reports on the reprap forum are all very positive.

The basic process to manufacture one as I understand it is

use a piece of Mic-6 tooling plate.
anodize the tooling plate to get an "openpore-surface"
dissolve some PEI in dichlormethane
wipe the solution over the surface so that the PEI got soaked into the pores.
let it dry

dicloromethane is nasty stuff.

[Viking]

After a quick search I found this one http://clever3d.de/epages/7a4290fc-7c7f ... -DeltaOnyx

[Jimustanguitar]

$150 for a PEI coated aluminum bed with a silicone heater pad... That's tempting. Salty, but tempting.

[teoman]

One of our members purchased one.

I prodded him to report back but then lost traco of that thread.

[Viking]

My PEI coated Alu plate has arrived, soon printing time...

[Viking]

Update on the Dauerdruckplatte:

I got one of these plates, 8mm thick, and tried to print at 90C. The result was like water on teflon.

Afte an email to the germans asking about the working temperature for this plate, they answered that I need to reasch 130 - 135C to get it to work.

The next question is, are the Onyx rev 7 heatbed powerfull enough to heat up 1kg alu to 135C ? Or can I feed it with higher voltage to manage this ?

[mhackney]

That's odd. One of the advantages of PEI is being able to print ABS at much lower bed temps. I typically print on an 85deg C bed.

[Viking]

Yes, thats correct, on my glass plates with attached PEI, it works at 85C.

So to get this Dauerdruckerplatte to work I ordered a 300mm dia 500w 220VAC silicon heater. I think I can controll this thru a SSD relay.

[Viking]

Alternative to my last post.

Is it possible to feed an alternativ voltage to the heatbed power connector, and 12v to the rest of the RAMBo ? After reading a lot about heating isues, I think I will try du connect an adjustable lab PSU to find out how much I have to ramp up the voltage to the onyx to be able to reach 135c. on 11.95 V it vil reach around 105c at maxiumum.i thinking it will need somwhere between 12 and 15V to reach 135c

[Xenocrates]

It should be pretty easily possible, although I don't know too many high amperage lab supplies (if you hit 24V's, you'll need at least 20. It gets worse from there). If you get over 15A's, you should switch to an SSR to control the power (use a DC DC one, not a DC AC model, the DC AC will stick open due to the nature of the circuitry inside).

[IMBoring25]

I like having an SSR in the system to get the high bed currents off the control board and I've just been running the bed off its own PSU, controlled through the SSR. Other options are converting to higher voltage for everything or running everything off a higher-voltage supply and using a step-down transformer for the lower-voltage components.

Based on the math, I think you'll need closer to 15V than 12, maybe even slightly more, depending on your ambient temperature and the efficiencies of the system. You're probably also looking at heavier wiring (which would be another recommendation for an SSR).

[Viking]

I plan to use an 320w lab psu where I can Limit the current and Voltage. I plan to take this in stages just to se what I need before I order a new PSU.

When I reach this higher temp on my print bed I will also go back and test the PEI tape I have, it's have the same carracteristics as the daudedruckerplatte when it comes to ABS printing.

[DeltaCon]

I know that aluminium transfers heat pretty well, but would it be possible that the Onyx reports the temp at the onyx bed, while the temp at the PEI surface is just not there yet? I have no experience using PEI, but if I would have to print at 130 degrees I would not even want that experience... Lately I have been pretty satisfied with my sanded glass bed and some Disappearing Blue Glue. For the parts with a small bed-surface I use the famous slurry. Al at temps around 85 because else it is too much irritating my impatience.

[Viking]

I have several variantion of PEI bed's I can use. I have the orginila glass plate with an 0.8mm pei sheet attached to it. it's possible to print at a setting of 85C, but if you go a little hihger to 90C you get a more stable adhesion to the PEI sheet. I also found that the PEI is an pretty good insulator, so I measure a difference from the onyx heater to the surface of the PEI sheet up to 12 C. This wil eben it'self out over time, depending how long you are willing to preheat the printer.

When it comes to thin PEI tape and this dauderdruckerplatte, I found that you need much higher bed temps, around 135 to get it working well.

[mhackney]

I know that aluminium transfers heat pretty well, but would it be possible that the Onyx reports the temp at the onyx bed, while the temp at the PEI surface is just not there yet? I have no experience using PEI, but if I would have to print at 130 degrees I would not even want that experience... Lately I have been pretty satisfied with my sanded glass bed and some Disappearing Blue Glue. For the parts with a small bed-surface I use the famous slurry. Al at temps around 85 because else it is too much irritating my impatience.

Absolutely that happens. You need to let the system equilibrate - which takes time. The aluminum heat spreader helps with this but it still takes time. How much time depends on your power supply and other factors (glass? glass thickness? good contact between bed elements? etc). For me, it takes about 6 minutes for the bed surface to reach the target temp.

[mhackney]

And to be clear - with the "normal" PEI that I describe and most of us use, you DO NOT print ABS at 130 degrees. 80-85 degrees is typical. This is another reason PEI is advantageous - you can lower your bed temp to minimize thermal stress and still get EXCELLENT first layer adhesion.

[Viking]

Now I have reconfigured my powersupply setup and done a test run with the glassbed PEI combo most of us use.

I used my lab PSU to power only the heatbed circut on the RAMBO. I set Cirrent limit to 14.95A and let it run free on voltage. First I set it to 100C wich it reached much faster than stock setup, and held it more stable too. here i drawed 14.95A at 18V.

When I did a test run to 135C at 14.95A limit, it reached 20V and still heated up reasonable fast. and much less fluctuations on the set temp when reached.



So I think I will change the setup to run on a SSR with a separat PSU set to 18v and max 20A, maybe with a tunable limiter on the current.

Then I will get a setup that can manage all my different print plates, and materials and run the prints at optimum temp for each plate / material combo.