Glue on sheet techniques  

Glue is used as a release agent for filament that tends to stick too tight.

Of the common filaments only flexibles really need glue - PLA should never need it, it can be useful for PETG on a *smooth* sheet but, frankly, window cleaner is better.

Flexibles (TPU&c) do reqire glue - if using gluestick draw ONE line across the sheet spread all over with a wet paper towel is enough.  If you use PVA soluble filaments keep some of the water you used to soak them free and that will work just as well.

For other filaments consult the manufacturer's spec sheets or see: https://help.prusa3d.com/materials

Always assume the glue is removed by the printed part.  Clean and reapply each time.

Cheerio,

RE: Glue on sheet techniques

I use glue stick to improve adhesion of ABS, and I just try to get it as smooth as possible, but I do get some undulations.  I would imagine a wet paper towel might work to smooth it out a bit, but I've not tried that yet.  Don't forget to wash the surface of your finished print, to remove any glue residue that was picked up during printing - I sometimes find that the undulations appear reduced after washing.  I find that the effect of the glue can last for 2 or 3 prints at least, but the image of previous prints can sometimes appear on the successive prints, so for that reason I tend to wash it off and re-apply each time.  I use Elmer's because it is purple when wet so it's easy to see where you need to wash.

I have recently started trying hairspray as an easier way to get a smooth layer, and so far it seems to be working well.  I haven't tried any really difficult prints with it yet though.  It does smell a lot nicer than glue stick!

RE: Glue on sheet techniques

thanks guys, I am trying to produce parts in PC Blend and I cannot get rid of some warping.

RE: Glue on sheet techniques

Which plate are you using .. smooth, satin, textured ?.

In the past I had trouble with PC blend on the satin plate. Even with adhesive, if the part was quite large. it always warped a bit. Now I only print PC blend on the smooth plate, using an adhesive/release agent. I found out that Dimafix works very well when the hot bed is at 100C or more.  Even so, depending on the size and geometry of the part, sometimes it’s convenient to add a large brim to avoid warping issues.

RE: Glue on sheet techniques

I'm using a satin sheet.

RE: Glue on sheet techniques

Is your printer even in an enclosure?

This is recommended by Prusa for their PC Blend.

And on a satin sheet, you don't need glue.

RE: Glue on sheet techniques

yessir, Prusa enclosure. According to the Prusa website, if you print regularly PCBlend you are supposed to gluestick the satin sheet as well?!?

RE: Glue on sheet techniques

I've had warping issues with ASA in the Original Prusa Enclosure at 40C + satin sheet. I bought 3Dlac Stick and it solved all my issues instantly. Zero warping, absolute 0 nada null, even on big parts and 7h+ prints. I'm amazed by this stick. The only thing I don't vibe with is the white residue left on the first layer, it can be reduced with some water and a bit of toothbrush scrubbing, but it's not gone completely. Oh well, I'll take it for the incredible reliability it provides.

RE: Glue on sheet techniques

I'm not using gluestick anymore, because it messes the smoothness of the bottom layer. For a general purpose adhesive I recommend 3Dlac/Laverneer./hairspray, which are basically the same product.  Some filaments require more specific adhesive/release agents. Magigoo has a wide selection for PC, PP, PA,TPU etc. but, as I said, Dimafix is excellent for hot beds above 100C.  That includes ABS, ASA and PC.

Nylon filaments are in a different class. They warp a lot and don't stick well to PEI surfaces, In my opinion, the best option for these filaments is the Prusa PA steel plate. that must be used without any kind of adhesive/release agent and cleaned only with hot water and a few drops of Fairy/Dawn.

RE:

"I would imagine a wet paper towel might work to smooth it out a bit, but I've not tried that yet."

This is the best and cheapest option I personally use to increase the adhesion of PETG on a steel plate. I gently apply some Kores glue in a few places and wipe the whole plate with a wet piece of paper towel. The layer is even, practically invisible and does the job. Nothing small peels off, large pieces don't lift at the corners. Please take into account that the plate should be cool before removing the print. If the parts are taken off after cooling, one such application of glue is sufficient for many prints.

"...it messes up the smoothness of the bottom layer...".
If you apply the glue correctly the first layer is perfect, they just grease the steel sheet instead of spreading the glue correctly. Don't worry about such comments, just try to do it correctly, it works.

RE:

Posted by: @chmax

yessir, Prusa enclosure. According to the Prusa website, if you print regularly PCBlend you are supposed to gluestick the satin sheet as well?!?

Please keep in mind that regular PC-Blend (the one without CF) will warp to some degree at nearly any condition you can reproduce with hobby equipment. A Prusa enclosure is an important improvement over no enclosure but won't suffice to eliminate warping altogether. It depends a lot on the part geometry and size how much it will warp in the end. Generally I would recommend to stay at diamters of roughly 10cm or smaller with PC-Blend parts. 

The hotter the enclosure the better. On my Voron 0.1 I reach 60°C in the enclosure and it still can not fully eliminate warping, part of the warping actually happens after cooling outside, slowly during the internal stresses. Such a hot enclosure does help considerably though compared to lesser conditions. You can also get fully functional parts out of your MK3 or 4 with a Prusa enclosure, it really depends what you are printing. 

Regarding adhesive. I had really good experience with Magigoo PC (mind you, specifically the PC version). A tad expensive but worth it in my opinion. Can be simply rinsed off with water afterwards (none of the smearing you get with glues like Kores or UHU Stick). Apply it not too thick. Just one way, not across. I had no adhesion problesm with brim and for non-challenging parts maybe the brim would not even be necessary. 

If you want to have a more even thinner adhesive layer you can try spray can (like the Dimafix spray). A stick will last much longer though I would assume and you can apply a stick also in your printer, while I would advise to apply spray adhesive only in well ventillated spaces away from your printer. You don't want to distribute the stuff all across your enclosure.