Protective films for 10' tablet pcs and transparent film for laser printers also provide reasonable quality. The second one gave me best results. But so far capton tape is best.

That's an interesting solution.

When using PLA I don't need the bed heated and the filament is at 185 or slightly lower.

I bought some 3M 6" wide Blue Painter's Tape at Home Depot at around $12.

I have a powder coating system in my garage. (another hobby) and use Green Polyester tape to mask the components. This tape is designed to handle high tempratures. As an experiment, I tried a 3" peice over my Kapton tape and have successfully printed several items on it. I haven't experienced any curl or lifting of the corners and can lower the temp on my bed. I started a print a while ago and the bed temp was only 64 degrees. It stuck with no problem and since the tape is designed to be removed easily after it is used, there is no problem removing it. It is less than half the price of Kapton. http://www.amazon.com/Green-Polyester-P … +tape+3%22 A 3" wide 72 Yard roll is only $20. A comparable 1Mil 3" wide roll of Kapton (only 36 yards) is about $40.

This sounds like a great alternative if the results are consistant.  Have you continued using this method with equal success?  Have others tried this with similar results?  Still waiting on my SD3 so have no personal experience as of yet.

from what I understand...

The reason that you use Kapton is that it can withstand the heat of the bed.
the blue tape is only for use with non-heated beds because it'll melt if it gets hot.

both the kapton and the blue tape supply a surface that the extruded plastic *should* stick to.

in a lot of ways you only need a few points of adhesion, just enough to stop the part moving. -and this is the point of the raft. if you have trouble getting the print to stick (at all) then try printing a raft, this is basically a huge mess of plastic laid of the bed to hopefully find some kind of "grab" to stop the parts moving around.

Warping/curling.

Warping and curling of parts is something completely different from issues of grab, the warping an curling is exhibited because plastic expands as is get hotter and contract as it cools.

The contracting action is especially concentrated at corners, (as the contraction is happening in effectively two directions, whilst on a flat side the contractions happen really only towards the centre.)

This means that when you lay down the first layer everything is fine, as the layers build up, the bottom layers start to cool (the hot end is no longer heating the bottom layers through conduction through the built part.) this means that the bottom starts to shrink and contract, without good adhesion this can mean that the part can come completely off the bed.

the heated bed is there to help stop the contraction from happening too quickly, the heated bed should be at or around the "glass temperature" of the part that's being printed to have maximum effect.

If you have significant problems of lift/warp/shrink then you may find that it's better to put a skirt on the bottom of the prints, this adds a very thick (xy) but very short (z) skirt around the part being printed, and appears to allow some extra material to shrink back into the part, and gets rid of sharp corners at the bed, at this point the skirt may lift, but the part should not.

http://www.bitsfrombytes.com/forum/post … stick-tape

Well, since the bed would be turned off, the only time the tape would be hot is when the plastic from the extruder is laid onto the tape. But, that's only for the raft or first few layers. The tape doesn't stay at that high of a temp throughout the entire print.

Maybe, but the plastic is roughly twice as hot as the bed would be depending on the settings and a hair dryer is enough to make temporarily temporarily unusable.

So you would in a sense be reversing the problem.

You have me interested in this concept, it would definitely be worth some testing.

I'm not sure how well that would work.

Standard tape adhesives don't work at temperatures that are too high.

If you could find tape that works at the required temperatures, great, otherwise kapton and a heated bed is the best solution for lifted corners.

Well, since the bed would be turned off, the only time the tape would be hot is when the plastic from the extruder is laid onto the tape. But, that's only for the raft or first few layers. The tape doesn't stay at that high of a temp throughout the entire print.

Yeah, I thought about it more after posting and figure it'd be safer to just keep the heated bed off and still use the double sided tape.

You could even cover the bed with one layer of the blue masking tape (to protect the bed) and then the second layer of double sided sticky tape(to keep the prints from lifting). Might add a little thickness to the bed and may need to be re-calibrated though...

I don't know, just throwing it out there... I'd try it myself if I could...

I'm not sure how well that would work.

Standard tape adhesives don't work at temperatures that are too high.

If you could find tape that works at the required temperatures, great, otherwise kapton and a heated bed is the best solution for lifted corners.

I would be worried about the tape melting, or at least the adhesive when working with a heated bed.

Yeah, I thought about it more after posting and figure it'd be safer to just keep the heated bed off and still use the double sided tape.

You could even cover the bed with one layer of the blue masking tape (to protect the bed) and then the second layer of double sided sticky tape(to keep the prints from lifting). Might add a little thickness to the bed and may need to be re-calibrated though...

I don't know, just throwing it out there... I'd try it myself if I could...

Kyle, what is the bed made out of for the dimension?

Some sort of plastic, not sure which.

Instead of the bed being heated, the print area is sealed and the air is heated.

Unfortunately, that doesn't work so well as you still get lifted corners on wide and flat prints.