The 3D Printer Thread

[Max-U52]

I have to admit that this is going much more smoothly than I thought it would. Usually when I take on a new area it involves a couple of temper tantrums, a crying Jag, and several phone calls to people who know more than I do before everything comes together. This, however, has gone very smoothly and I've already accomplished a couple of the goals that I set for myself. I knew that buying the printer was only the start and I figured The Next Step would be to learn how to print files that other people had sent me, and then learn how to print files that I had modified after other people had sent them to me. I've now done both those things, so the next step is for me to learn how to create files of my own. This will obviously be the most difficult part of the process, but I really am looking forward to it and I have a couple of four-day weekends for the holidays so I should have plenty of time to practice. I don't think I could have gotten so far so fast without the help of Wayne, Wibbs, and Alwyn, so a huge thank you to all three of you for all your help.

[midlife306]

Your more than welcome Gary


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[wibblywobbly]

If you get stuck on anything, just shout, I am sure all of us are more than willing to help where we can.

[Max-U52]

If you get stuck on anything, just shout, I am sure all of us are more than willing to help where we can.

Thanks guys, and I've always known that I could count on you fellas. In fact, one of the things that made me decide to go ahead and buy the printer was that I knew if I had problems there were plenty of guys here that would be willing to help me out. Just one more reason that I'm always saying we have the greatest hobby community in the world.

[Max-U52]

This may seem a dumb question, but why does everyone use glue instead of the tape that comes with the printer? Is the glue just better, or is it so you don't have to keep buying tape, or what?

I'm having some real problems with adhesion but after looking online I find I'm not alone. Apparently the CR10 is known for crappy, warped glass. At least there are a million fixes for the stock glass listed online. But one popular fix seems to be 12x12 mirror squares from home depot, so I'll be stopping there today.

[AlwynTurner]

Hi Gay, I also had issues with the glass. I found that if I set up the four corners then the centre was pretty much jammed to the glass, so then I tightened each corner by the same amount until the centre was set correctly, and found this worked, then used pritt stick and haven't had any adhesion problems since.

Alwyn

[Max-U52]

Hi Gary, I also had issues with the glass. I found that if I set up the four corners then the centre was pretty much jammed to the glass, so then I tightened each corner by the same amount until the centre was set correctly, and found this worked, then used pritt stick and haven't had any adhesion problems since.

Alwyn

Glad that worked for you, but I've tried everything and the glass is just too badly out of flat. I'm going to try the mirror and see what happens. The glass that came with the printer isn't bad for small prints, but anything over about 4.5 inches and the edges lift on me.

[wibblywobbly]

Clean glass is terrible for making parts stick. The cheapest and most effective way to do it is to get hold of a Pritt stick, it is solid PVA glue. Smear it over the surface before printing. I use builders PVA liquid, a few drops on the surface and wash it all over the surface with a wet brush. Same stuff but a bottle will last years.

That said, if the bed levelling isn't set up, then parts will still fail to stick. It needs to be done around every ten prints as getting well adhered parts off will move the adjustment over time. If parts are well and truly stuck then spraying with water releases them. PVA is water soluble. The glass usually has a good and a bad side, so flipping it sometimes works.

The tape is a pain, and pointless if PVA is used, I have never used it. It is a throwback to the early days of 3D printing.

Buildtak sheets work well, but too well, the sheets are expensive and the parts weld themselves to it, then the surface gets damaged trying to get the parts off.

I just use PVA, and run over the surface with a scraper to remove any residual bumps before printing, one coat lasts around 5-10 prints. I never wash the glass, just scrape the surface. Over time, the glue builds up and self levels the surface.

If the bed levelling isn't good then no amount of mirror glass, glue or anything else will solve the problem. I can put my hand on my heart and say that I can press print and walk away, I don't have any issues with parts sticking on my CR-10.

One thing that should be done is to check every bolt on the frame, and to see where the levelling is out. If there is any droop on the X axis bar that holds the hotend it will throw the Z height off, and this makes the bed levelling inaccurate. Any droop can be removed by adjusting the concentric screws, it takes a bit a of fiddling about but after reading about it on the web, it improved accuracy. If the hotend is hitting previous layers it will knock the part off the bed eventually.

[Max-U52]

OK, I really appreciate the help but I don't think I'm getting through so let's try this again.

The glass that came with my printer is crap. If I put it in and level the corners on side A the nozzle then scrapes the glass in the center of the bed, and if I turn it to side B and level the corners I then have a .015 gap between the glass and the nozzle. I've read all the stuff about shims and using aluminum foil and all the other tricks to fix a bad piece of glass, but I can get a box of four mirror tiles for less then ten bucks and I have yet to find anyone that says the mirror does not work, everyone that has tried it is still using it. The mirror image itself is not the point, it's the fact that mirrors have to be flat and of consistent thickness to avoid distortion and therefore make good printer beds (after you wet sand with 320, which I will).

I suppose the proof will come when I put in new glass. If I then start getting good adhesion we'll know I was right, and the glass that came with my CR10 is crap. If I still have problems that could mean a warped aluminum bed, which seems to be another common problem with these, but from the way it's acting I don't think that's it. If the bed was warped I believe I would have the same trouble with both sides of the glass, not two different center heights.

[Max-U52]

By the way, Wibbs, I'm using your method with the PVA, and I'm using elmer's and I just apply it to the bed and paint it with a wet brush. Seems to work very well on small prints, but on larger items the edges are just too much lower than the center and they want to lift around the edge but still leave the center stuck in place. I think with the center being so much higher it's got too much gap around the edges and that's causing the lift. I'm off to the market right this minute so we'll know by the end of the day (tomorrow morning for my British buds that are 5 to 6 hours ahead of me!).