Spring steel PEI sheet recommendations?

droftarts

I'm upgrading my printers to aluminium Ecocast tool plate (thanks @deckingman!) and want removable magnetic PEI spring steel sheets. This means having the stick-on magnetic sheet too. Anyone got any recommendations for good quality PEI sheets?

Also, any advice on the aluminium tool plate thickness?
For my bed-slinger, I was going to go for 250x250x5mm aluminium tool plate and Keenovo (or similar) 240x240 silicone 350W 24V 14.5A heater wired directly to Duet, which should be good for 100C. As it's a bed slinger, I want to keep the weight down a bit, so 5mm thick; 4mm feels just a bit flimsy, 6mm adds a bit more weight.
For my CoreXY, I have chosen 350x350x8mm, again with a Keenovo heater (probably mains powered, yet to decide, happy for recommendations). The bed will be kinematic, on 3 leadscrews. Is 8mm okay for a bed this size?

Any thoughts and guidance greatly appreciated.

Ian

fcwilt

@droftarts

The vendor I use for CATP lists better flatness specs when the thickness is 0.5" or more - 0.005 versus 0.015 when thinner. Of course those are worst case specs.

CATP flyer

I have some beds that have milled pockets for discrete magnets which work great except with inductive Z probes.

The flexible magnetic sheets with adhesive backing don't appear to bother inductive Z probes but you have to be aware of the max temperature ratings.

I have those as well but none of the filament materials I use need bed temps that present a problem for the flexible stuff.

I have purchased a number of products from Amazon and directly from China. They all seem similar.

I have a lot of BuildTak stuff but I understand they have changed their magnetic sheet product to something that uses small discrete magnets
and has been described by some users as "inferior" to what they used to use.

But all of the flexible metal sheets stick to all of the magnetic "sheets" so you can "mix and match".

Frederick

deckingman

@droftarts said in Spring steel PEI sheet recommendations?:

............ Also, any advice on the aluminium tool plate thickness?.............As it's a bed slinger, I want to keep the weight down a bit.................

Maybe work backwards and use the thickest that your motor can move at the required rate of acceleration. There is a useful calculator here that you can use to get the weight of various thicknesses. https://www.omnicalculator.com/construction/aluminum-weight

droftarts

@deckingman Thanks. The aluminium bed, silicone heater and magnetic PEI sheet is going to replace 3mm MDF, PCB heater, 4mm glass and binder clips (very old school!) which I can at least take off and weigh, so that calculator will come in handy to work out if I can make something in the same weight range.

Ian

deckingman

@droftarts said in Spring steel PEI sheet recommendations?:

@deckingman Thanks. The aluminium bed, silicone heater and magnetic PEI sheet is going to replace 3mm MDF, PCB heater, 4mm glass and binder clips (very old school!) which I can at least take off and weigh, so that calculator will come in handy to work out if I can make something in the same weight range.

Ian

I reckon your glass will weigh about 780gms and the mdf about 142 gms making about 920gms. I wouldn't have though the PEI sheet was anything significant weight wise and maybe the PCB heater would be about the same weight as a silicone heater. 5mm thick aluminium would weigh about 840 gms so a bit less than the mdf/glass combo. 6mm thick aluminium would weigh about 1000 gms so a little more than the mdf/glass. If you used 6mm and found the motor struggled a bit you could either slow down the Y acceleration or maybe fit a bigger motor (or print smaller parts ).

If you are intending to use mesh compensation, then I don't suppose it makes much difference.

zapta

@droftarts, I am y happy with my Enegetic pei magnetic sheet. It’s thin, one sided, and smooth, and I get very good result. It was the recommended sheet in the voron part list at the time I built my printer.

oliof

@droftarts mueller-bestellungen offers genuine ultem and FR2 surfaces.