Releasing a print

I was wondering the best way to release prints from the kapton tape. A tall print is quite easy, just tap it with a small hammer and it comes away no problem.
When it comes to low prints like the large extruder cog, I try to prise the print off but always damage the tape, any suggestions on how to remove the print without damaging the tape. I also use PVC cement, works great, but again difficult to release low prints.

John

Omerod 096

Hi John, I've been turning the bed off, leaving for a couple of minutes then just tap them with my fingers.

What settings are you using for Slic3r by the way?
Tried nearly all the ones that are suggested, but if doesn't seem to work.
Try as I do, I can't seem to get it to work. I get some of the first layer, then nothing.
The printers working fine with the coat hot...(if I make any more I'll open a coat hook shop).
Works fine with the calibration test pieces.... But when I try to print something I've sliced,
no joy.....

Kim

Let the bed cool down to 40C, at least. Then use anything that can catch on the printed part, but does not interfere with the bed. For example, on the extruder large gear, I usually put a long M3 bolt down the centre, and lever in a few different directions to loosen it. I try not to lever against the bed with a screwdriver. It's usually easier to put a similar height object on the bed, or print two parts close to each other, then lever on that to get the part off.

Ian
RepRapPro tech support

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KimBrown
Hi John, I've been turning the bed off, leaving for a couple of minutes then just tap them with my fingers.

What settings are you using for Slic3r by the way?
Tried nearly all the ones that are suggested, but if doesn't seem to work.
Try as I do, I can't seem to get it to work. I get some of the first layer, then nothing.
The printers working fine with the coat hot...(if I make any more I'll open a coat hook shop).
Works fine with the calibration test pieces.... But when I try to print something I've sliced,
no joy.....

Kim

click the box Use relative E distances in Printer settings general

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arnaud31

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KimBrown
What settings are you using for Slic3r by the way? Kim

click the box Use relative E distances in Printer settings general

Install our profiles: [www.reprappro.com]

Ian
RepRapPro tech support

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droftarts

Quote
arnaud31

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KimBrown
What settings are you using for Slic3r by the way? Kim

click the box Use relative E distances in Printer settings general

Install our profiles: [www.reprappro.com]

Ian
RepRapPro tech support

Last I ckecked, supplied profiles did not use relative E distances and so nothing can be printed.
The same goes with the gcodes of the build plates supplied online, they use absolute E distances and it won't print, extruder backs off and then printer starts to print thin air.
I had to re-slice the STL to print my spare set of parts...

Edited 1 time(s). Last edit at 01/20/2014 08:36PM by arnaud31.

Also the Extruder 1 retraction length is still set to 1mm in the supplied profiles (checked just now), but needs to be increased to about 4mm for good-quality prints.

Edited 1 time(s). Last edit at 01/21/2014 03:41AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks for your reply Ian. I'll give it ago. I think this was a classic hijack of a topic

John

Releasing a print is much easier when it cools down. Many suggest switching the bed off and then removing. That wastes too much time and energy for me, especially if I want to run another print. So here is what I do:

1) I got myself a few extra 3mm thick pieces of float glass, cut to the same size as the one supplied. Really cheap. You can probably go to any shop that sells window glass and order it ready made. If you are braver get yourself a larger sheet and cut it with a normal wheel-type glass cutter.
2) Lightly glue normal pieces of foil on the corners, but not right up to the edge - as you you don't "home" there and it leaves a few millimeter for the Kapton tape on the sides to adhere to the glass and cover the foil. Apply Kapton tape as usual.
3) Make your print at the the 50C to 110C.
4) At the end either end off you print with a reset to the higher temperature in the Gcode (not recommended as you might forget it when unattended) or manually set the temperature back to printing levels with Pronterface. That way you retain all the heat in the PCB heater and ally sheet.
5) Remove the clips, carefully take off the glass and let it gently cool elsewhere and put the next glass plate on the bed. You will see a drop in the bed temperature readout and that is because the glass is now still at room temperature. I have not had one snap on me. Load your next print and let it rip.
6) Don't put the hot glass plate on something cold, like a metal plate or running under cold water. Especially at 110C you might just snap the float glass. I would suggest just leaving it alone on something like a book somewhere until it reaches room temperature. But while this one is cooling down the next print will be going already. When cold the prints come of very easily.

Thankyou for your suggestions Victors. I think my main problem is impatients and I should wait for the plate to cool before trying to remove.
I will get another piece of glass to enable quick print changes.
John

Ormerod 096

With my ABS prints, which I make on glass coated with solvent cement rather than Kapton, I remove the glass and put it on the bench, and after a minute or two cooling I'll hear a sharp "crack" and the print then pulls off easily. (I expect one day the "crack" will be the glass breaking instead of the print freeing itself). If I'm going to make another print I leave the bed heater switched on, patch the glass with a quick wipe of solvent, and put it back. I always recalibrate the bed though, because just removing & replacing the glass changes the levels. I plan to modify the bed so it remains consistent.

Just received my first reel of ABS so I'll give it a go. Picking up the new pieces of glass tomorrow so if the glass does break I'll have a spare

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johneato
Just received my first reel of ABS so I'll give it a go. Picking up the new pieces of glass tomorrow so if the glass does break I'll have a spare

Have fun! To recap my experience - set bed to 100 deg for first layer, then down to 90 (helps stop warping). Put a sheet of white cardboard or something over the bed while it is heating to get it to temperature more quickly (it still takes ages). While you still have PLA parts, wind up the Z axis and remove the extruder from over the bed while the bed is heating to reduce the time they are exposed. Hotend at 240 to 250, but do not turn it on until the bed is almost up to temperature else the ABS will start cooking during the long wait for the bed to heat. Print on plain glass coated with solvent (pipe) cement - ABS has difficulty sticking to Kapton. I smear it on thin with an old credit card. Your first print jobs should be the X-carriage, hotend mount, extruder parts, fan parts. Ray Hicks's mod of blocking off the existing 3 cooling outlets (he cut them off completely and blocked the duct), and providing a new outlet for the expelled air through the top of the duct improves ABS printing slightly as well, though it's not imperative, and will probably be detrimental to PLA prints. Apparently the fumes from ABS are a H&S issue, so ensure adequate ventilation.

dmould
Thanks for your advice, I still haven't progressed to ABS yet due to failure of my Z drive and then taking too long to diagnose a problem with slic3r that kept freezing my printer. I am once again printing reliably with PLA so with confidence returning I will have ago with ABS and let you know the outcome. I have already become a fan of solvent pipe cement and prefer it to kapton tape. Much easier to prepare the table and to repair if the surface gets damaged.

John

Dave, now you've brought up MSDS H&S, I think I introduced the Marley KS10 cement (I didn't have any acetone or abs at the time to try ABS goo) - but it DOES have MSDS issues because of the solvent mix and epoxy monomer [www.google.co.uk] (can't find a direct link to product info on their website without login- that link is to MSDS/compliance document), worse than ABS (or acetone, and isopropanol - which are also pretty nasty). I'll have to fit extraction anyhow for the ABS (and acetal/POM when I get round to it) and I work in a well ventilated environment.

Ray

Edited 1 time(s). Last edit at 01/22/2014 04:20PM by rayhicks.

I'm not that bothered about H&S at home (much of it is OTT, and at my age I no longer worry about long-term effects that take many decades to materialise!), but at work I have to be careful about possible claims that I am endangering other employees. The H&S inspector even measures the temperature of the water from our hot taps to make sure it is barely warm. At home I have it set so I can make coffee without bothering with a kettle. I've already had complaints about the fan noise (wimps!). I might have to contact the council about that. If they were to dig up the road outside the factory, it would drown out the fan a treat. New quieter fan due to be installed tomorrow. Maybe I'll put up a sign saying, "Caution, do not breath in this area". It can go next to the one that reads, "Warning - this warning sign has sharp edges". With H&S, warning signs are often an acceptable substitute for actually fixing the problem.

Dave
(#106)

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dmould
The H&S inspector even measures the temperature of the water from our hot taps to make sure it is barely warm.

I remember my H&S inspections when I ran a company with 20 employees. On the first one, the inspector found a trailing cable (trip hazard) which he told us to get rid of, but said everything else was OK. For the second, we made sure there were no trailing cables or any other obvious hazards. The H&S inspector started picking up on stupid things, e.g. "You've got bleach in the cleaning cupboard - someone might drink that!". So after that, we always put out a trailing cable when an H&S inspector was due, so that he would find it, tell us off, and be happy that he had done his job.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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dc42

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dmould
The H&S inspector even measures the temperature of the water from our hot taps to make sure it is barely warm.

I remember my H&S inspections when I ran a company with 20 employees. On the first one, the inspector found a trailing cable (trip hazard) which he told us to get rid of, but said everything else was OK. For the second, we made sure there were no trailing cables or any other obvious hazards. The H&S inspector started picking up on stupid things, e.g. "You've got bleach in the cleaning cupboard - someone might drink that!". So after that, we always put out a trailing cable when an H&S inspector was due, so that he would find it, tell us off, and be happy that he had done his job.

Quite true. I usually prop a door open with a spare fire extinguisher just before he arrives. After he goes for the bait, we can then have a polite discussion about exactly why it constitutes a hazard, which I can gracefully concede and he goes away happy, having won the argument.

Dave
(#106)