I'm A Convert! PEI Heated Spring Steel Bed Plate Surface

[Artur5]

Below you see a part of the hotbed's bottom. The rectangular magnets are glued all around the perimeter ( and also in the center). Being embedded in lozenge shaped gaps of the bed, they're flush with the surface. The glue fills totally the hole.
If you had to glue them on a flat surface, the magnets would stick out and would be far more difficult to keep them attached.

 

[The Hat]

If somebody wants to add magnets on the bottom side of a hotbed, I expect that they need to be glued really wel

OK guys, this someone wants to start out fresh and wishes to dump the 3M magnetic plate completely, and I figured metal round magnetic pieces would be a better option, that would give me more flexibility to try out this steel PEI sheet or other materials too..

I have two printers using the 3M adhesive plates but it’s not easy to change from one type of surface to another without pealing this strip off the bed, and you know how hard it is to get that Feckin stuff off.

I'll bet you a beer you won't need any additional magnets!

So I go to the trouble of using the steel PEI sheet, and say it lifts on one edge ? then I’ll have a sheet that has a permanent warp, that's a possibility and could happen, so for me I reckon the belt and braces approach would be better.. Double magnets on each corner..

I look forward to hearing your experience!

I bet @Artur5 will be also..

 

[Nifty]

in lozenge shaped gaps

I've NEVER heard this used like this... but I love that you used it!

lozenge: a rhombus or diamond shape.

brilliant!

LOL!

 

[Redbrickman]

On thing I found out about PEI sheets. They need to be cleaned properly with dish soap periodically. Using IPA does not completely clean the surface as it leaves a film. Best to take a sponge with dish soap and water on it and wash the suface, then dry with a clean micorfibre cloth or a piece of kitchen roll. Do not touch the surface after that with your fingers!

PEI can also get too smooth after a while and sometimes even when new. The solution is to lightly scuff the surface with the green side of one of those washing up pads, I usually add some soap and water and gently rub the entire surface then rinse and dry it. You only need to do this very occasionally and don't use much pressure.

I have learned all this after a frustrating time thinking IPA cleaned the surface and hours of not getting the prints to stick then reading about it

One other thing I learned from the Voron builders forum is that Acetone which some people use to clean the PEI will eventually damage it.

As for the magnetic sheet, the Chinesium ones are OK but are not great if you have a large piece printing on the bed. If you want to splurge out buy a Graviflex sheet. It is fine up to 130c temperature and the pull on the flex plate is amazing. Without a little tab on the steel sheet I reckon it would be near impossible to lift it off again.

Problem with using magnets is any machine with an inductive probe for bed leveling needs to have the probing software set up so it does not probe over the magnets. Thats is why many people choose a magnetic sheet as it has a uniform magnetic flux over the whole area.

 

[Artur5]

A lazy old fart like me doesn't cleans the PEI surface with soap and hot water after every print. I spray a thin layer of 3Dlac every four or five printing jobs and no more worries about parts getting loose from the bed.
Only when the coat of lacquer starts to wear visibly I clean the bed with dish soap and warm water. Be sure to get a brand free from additives/scents, which always leave a greasy residue. I use Fairy 'clean and pure', totally colorless and transparent like spring water.
PLA should stick well with no adhesive on a smooth PEI plate but PETg and specially flex (TPE/TPU) stick so well to the bed that you must use an intermediate layer of glue stick, 3Dlac/hairspray or similar to avoid damaging the PEI film when removing the model.

@Redbrickman.. good point about the magnets/inductive probe question.
My printer performs automatically a mesh bed leveling before starting a print job. The user can choose between a pattern of 3x3 ( 9 probing points) or 7x7 ( 49 points). So, either the probing avoids carefully the proximity of the magnets or they figured out how to compensate for the magnetic flux distorsions.

 

[Nifty]

On thing I found out about PEI sheets. They need to be cleaned properly with dish soap periodically. Using IPA does not completely clean the surface as it leaves a film. Best to take a sponge with dish soap and water on it and wash the suface, then dry with a clean micorfibre cloth or a piece of kitchen roll. Do not touch the surface after that with your fingers!

Interesting! I've been watching all the videos about IPA and so I've been using that... and it seems to work, but I'll keep an eye on it and use dish-soap if I run into problems getting things to stick.

PEI can also get too smooth after a while and sometimes even when new. The solution is to lightly scuff the surface with the green side of one of those washing up pads, I usually add some soap and water and gently rub the entire surface then rinse and dry it. You only need to do this very occasionally and don't use much pressure.

Ya, I've seen lots of videos where they even use steel-wool! I pealed off the protective sheet on my smooth side and have been using it as-is ever since. I've got the other textured side as well.

Basically what I've found: I have had zero adhesion problems so far, especially if I heat the bed and/or use gluestick. (disclaimer: I haven't done any HUGE / long prints yet).

 

[Artur5]

@Nifty, now that your PLA filament and PEI plates are in such friendly terms, it's no fun anymore.
Try ABS, PC, Nylon or PP if you want to enjoy the thrills (i. e, endless headaches ) of bed non-adhesion and warping.

 

[The Hat]

if you want to enjoy the thrills (i. e, endless headaches ) of bed non-adhesion and warping.

You forgot to mention the whip and the bed of nails…

 

[Artur5]

So I forgot..
I have no whip. Do you think printing it with flex TPU be OK.? It's an elastic filament but tough enough for punishing purposes.

 

[NurseBob]

I started my 3d Printing journey using blue painters tape on a bare metal bed.

I then converted to using gluestick on a cold glass bed: https://www.printerknowledge.com/threads/bed-adhesion-tricks-and-tips.12128/page-9#post-109242

This worked great for years. Biggest issue was getting really large (surface area against the bed) parts off the glass without breaking the glass, my bed, or stabbing myself with the scraper.

I then tried a magnetic sheet, but wasn't happy with it (probably partially due to low-quality magnet and sheet): https://www.printerknowledge.com/th...sted-new-magnetic-flex-sheet-print-bed.14464/

... and went back to cold glass / gluestick.

Again, mostly happy with it, except for large parts.

Well, after seeing TONS of videos with guys using PEI on spring steel sheets, I decided to order one. I decided to "splurge" and get the double-sided sheet with smooth PEI on one side, and rough / powder-coated PEI on the other:
https://amzn.to/33KFKgS
View attachment 13786

I've been experimenting with it for about a week and am VERY happy with it!

There's still a part of me that doesn't love waiting on a heated bed to warm up (heck, I get frustrated waiting for the nozzle to heat), but I think the Ender 3 V2's smaller bed AND 24 volt system (with the sheet metal vs. fat glass) heats up way faster than my CR10 big bed, 12v, thick glass, so I may start always printing with <gasp> a heated bed! </gasp>

... that said, I still like experimenting, so I've been playing with combinations of bed temps on the smooth and rough sides, as well as using and not using gluestick.

I found that the textured side needs at least 60 deg. for the parts to stick and then do the magic self-release when cold.

The smooth side is more forgiving and I can get a decent "stick" at 40, and even 30 deg.

I might still do cold bed + smooth-side-PEI +gluestick on small quick prints... which is like 90% of the stuff I print, and then do a fully heated + rough-side PEI for really big / long-duration prints.

All-in-all, more fun stuff to experiment with!!!

My "new" Prusa I3 came with the PEI platen as a stock item; it's printed flawlessly for the last 18 months with minimal maintenance. Only minor challenge, PET sticks TOO well, though that can be addressed with platen temp, for the most part. I love "popping" prints off the surface. So far I've successfully printed with ABS, PLA, PET, and Flex filaments. The two brands I've dealt with have been Octave and Hatchbox. Good results with both. I have run through several 1Kg spools. Heated PEI magnetic plattens Rule!