@calinb - GG sounds interesting. What's the clean up process like?

I've been trying to come up with a way to distribute the shear forces at the glass/print surface interface to prevent glass chipping. I've had some success with putting down a layer of high quality tissue paper on top of a glue stick/water slurry. Letting it dry, and then cooking it at 110C for a half hour. After cooling, covering with ABS juice. So far, this surface produces much better results than Kapton, PET or PEI. The tissue just peels off the glass after printing and stays mostly attached to the print. The tissue fibers are easily removed from the print with water and a soft scrubby pad. Nice matte uniform surface. I'd probably stick with PEI if I was doing a small quick print, but the extra prep time of tissue is worth it for really large day long prints that cover the bed. Also tried gluing down a sheet of engineering pad paper, but it popped off the glass when it was being heated. For some reason the tissue sticks.

I'm still experimenting. First time I did the tissue thing, I got some amazing prints, as good as with juice on glue stick on glass. I lost part of the recipe on the next set of prints because there was some lifting. Can actually tell the exact time the section of the print broke loose because there was a squished layer on the perimeter of the print. The amount of lift was 0.4mm which was how much shorter the part ended up being. I think the separation occurred at the glue/tissue interface since there was still glue on the bed and the tissue was attached to the part. Part of the problem is controlling the how much the glue stick gets diluted in the slurry and how much gets absorbed into the tissue.

I wonder what would happen if I combined GG with tissue? might also try Polycrylic with tissue.

@dentist - I would love to find some 5 mil Kapton. I did use some heavy duty 2 mil PET applied dry, but the adhesive foamed up and lifted during a high stress 10 hour print. If you decide to go for PEI, be prepared to have a removable print surface. You can't really pry anything under the print, but putting the bed in a deep freeze for 30 minutes has the part just popping off. I finally did get pretty good ABS/PEI adhesion with bed temp of 115/110, but the 467MP gave up the ghost again. It formed a large 35mm blister where the 30 mil PEI pulled away from the 467. I am going to revisit the PEI, because it will probably be the go to for small light duty prints because of convenience. Seems like the weak link is these gooey bubble gum silicone and acrylic adhesives. Need a way to BOND the PEI to the bed.

I had a scary revelation. Placed a straight edge across a 3mm thick glass bed supported on the edges (250mm) and pushed down in the middle few pounds of force. Surprised by the amount of deflection. Easily equivalent to what the glass is experiencing on a large print. Next printers will use an aluminum plate like yours! (probably stick with a coreXY or Delta so that mass won't be flying around)

Experimenting with different kinds of paper and learning about various paper manufacturing processes. I am going find a source and get some Esaki tissue ordered. "Expensive" but it has some unique characteristics. Tried some gift wrapping tissue, and it just dissolved.

@calinb - been thinking about your comment that the glass seems stronger when it is hot. I have had the same feeling. Most of my glass divots happened with a fully cold part and bed. I'm going to sacrifice a boro bed and run some big parts with the Juice on Glue Stick. I will let the parts fully cool, then reheat the bed to 100 or 110C before prying it off. Part of the rational is heat soaking the surface of the part should reduce shear forces between the part and the bed. Also those temps should be close to the heat deflection temperature of ABS. Pulling the part off cold is asking for trouble. As the part releases when it is being pried up, there is a fissure that has to form between the glass and the part. As it propagates, the wave front is testing the interface between the glass and the part for any small defects in the glass surface. If the fissure hits a defect, it can dive under the surface of the glass and continue propagating. I suspect that just cooling the part in place on the bed is ok because there is no normal prying force trying to rip off the surface of the glass. None of my broken beds initially ever cracked in half. The damage has always been a divot where the front dives under the surface of the glass. Shrink on ABS is at least 0.5%, so a 200mm sundial print will shrink 1mm when it suddenly releases.

I just saw that the 1 1/2" wide Lucent Path 5 mil Kapton tape has been price cut to $64 for 36 yards. That's enough to last at least a couple years...

[www.amazon.com]

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

@calinb - Success! Back to ABS Juice on Gluestick on Glass - Parts just peel off with a bed temp of 60C! I have been letting the bed cool down to room temp and then reheating to 60C and holding it there for about 5 minutes. Slip a single edge razor under the part and then insert a small 0.5mm thick frosting knife. The knife separates the part from the bed with little effort. The glue stick layer is softening and releasing. So far there appears to be plenty of glue left on the bed that it is ready for a new print with just a recoat of ABS juice. Next I'll try just letting the bed cool to 60C after the print is complete and skip the cool down to room temp. Take away - DONT PRY PARTS OFF GLUESTICK ON GLASS AT ROOM TEMP.

I ran some experiments with Titebond II. For whatever reason, it did not work as well as Extra Strength, but since it is water resistant when it drys, it took a lot more work to clean off the glass. I would think the GG would be similar for cleanup? Worth keeping the GG in mind though for Uber hard to print parts. Maybe try removing GG at 70C?

Some colors of eSun ABS stick well to gluestick without the need for ABS Juice. I will try some direct prints on gluestick of some of the colors that pulled glass chips, and see if they also release easily at 60C.

Some colors like white have don't adhere well to gluestick, and benefit from coating of ABS Juice on the gluestick.

@calinb - Have you tried Taulman 618 on ABS juice? it wasn't in your list.....

My observation is that all gluesticks are not created equal. I've had no success with Elmers Washable Purple. The bed heat really softens it. Same problem with Aquanet HS. I'll be ordering more Elmers Extra Strength and hoping they have NOT changed to formulation.

@dentist - Yeah. I saw the Kapton Amazon link for the 1-1/2". Lucentpath was nice enough to take back the last thinner roll I ordered from them because it blistered badly. There was also another reviewer that talked about blistering. I'm wondering if they changed the adhesive formula after you ordered your Magic roll.

Learned a lot over the past 6 months.

Warpinator 5000 is easy and looking for something more challenging!

I reverted back to simple glue stick on glass. Using Elmers Xtreme since is seems to be commonly available.

Self heated chamber running at 50C. Glass bed 115/95. Extruder 260/250. Std eSun ABS.

First two months, I managed to get some good prints, but was pulling chips off the bed.

What I have learned since is never ever ever no-how no-way, pry or twist a part off the bed. That's were chips come from. In many cases, large prints release themselves. Sometimes they bounce around inside the printer. If a part is stuck down, especially small parts, just create a puddle of water around it and wait. It may take 10 minutes to a couple of hours, but it will self release. Sometimes reheating the bed with a water puddle around the part speeds up the process. I do pry up any brims with a razor blade, but never try to lift the part. Haven't pulled a chip in the last 4 months. I've been printing some very tall narrow walled parts without lifting. I have resorted to some extra hold down pads in some cases, but the stick is pretty amazing. The thought of going back to Kapton or painters tape would be like reverting to the dark ages.

For prep, put a little glue stick on the bed. Dip a latex glove in few drops of water and use to dissolve the beads of glue stick. Final coat should not be super thin or thick. Then start heating the bed and continue to move the glue around with the glove until just before it starts to become tacky. Close the printer cover and cook the bed for 5 minutes once it reaches 115 to drive out all water. If you start with too much water in the slurry, and try to cook it directly, it become too porous from escaping steam bubbles. The higher bed and extruder temps seem to activate the attach to the glue stick. Also run first layer at 15% of normal print speeds.

Over exrude the first layer so that is no gap between adjacent lines. Bottom layer should be mirror smooth.

I have a new coreXY in the works that is using Z belt drive. Also leveraging some of @dentist 's frame construction techniques. Amazingly rigid. It is using tooling plate aluminum bed with custom Chinese heater pads. I will be experimenting with a 300x300 Print Bite surface. I am hopeful, but it will be hard to beat glue stick/glass.