Questions about warping and supplies

[billdempsey 0]

I'm getting warping on the ends of long parts, but a raft eliminates it. Sadly, taking the raft off is a major pain. I've seen other posts in the forums that using two layers of blue tape helps. I also heard wiping down the tape with acetone helps. Others say you should get a heated bed. Anyone have experience with any of those methods? What works the best?

If I wanted a heated bed, where would I get it? Does Cura support it? Does it just connect to the Arduino board?

Also, I'm looking for a U.S. source of high quality PLA filament that works well with the Ultimaker. Between the bad exchange rate and the high shipping, buying it from Ultimaker costs over twice as much. Any suggestions for a supplier?

[Daid 306]

There is quite a bit info about the heated bed if you search for it, but you'll have to build it yourself as we don't sell any yet.

But tried a brim? In Cura, if you set the skirt distance to 0, and the line count to 5. Should help keeping the part down and is easier to remove then a raft.

[billdempsey 0]

Awesome! I'll try that! Thanks again Daid! I vote that you get a raise.

[snowygrouch 1]

I have printed very big parts in PLA that hardly warped at all.

You will find that the initial z height is absolutely critical regarding the adhesion to the

bed. If you are too high up the things will ping off easily and hence will not be stuck down..

too low and you will have horrible grinding as the nozzle moves over the oversquished bead

of PLA.

Also over extrusion has the effect of curling the edges up too. You will notice this as parts

looking bloated, like a balloon filled with too much air.

Depends also what temp you are printing at and so on. The hotter you print, the more the plastic

will cool before solidifying...so more warpage. I print 1st layer at 230 and rest at 220 Deg.

C.

[banana97 0]

Try incorporating 0.2mm thick discs at the corners on the base of the model. The diameter needs to be big enough to cover the corner where the warping occurs. Also decrease the first layer height to 0.2mm and make the fan turn on at the 3rd layer. the I did this and found little or no warping afterwards.

[billdempsey 0]

I solved the warping. First I tried the skirt, which seemed to help a little, but I still got corners pulling up a bit. Next, I turned the fan off. When I print without the fan and with the skirt, it just doesn't warp. I'm pretty happy with the quality of the prints now.

Here is an amplified iPhone dock I designed and printed yesterday.

EDIT: I spoke too soon. I'm printing an item which is 190mm wide and at the very end, it still warped. Even with no fan and a 10 line skirt. Five hour print, so a little disappointing.

[billdempsey 0]

I have printed very big parts in PLA that hardly warped at all.

You will find that the initial z height is absolutely critical regarding the adhesion to the

bed. If you are too high up the things will ping off easily and hence will not be stuck down..

too low and you will have horrible grinding as the nozzle moves over the oversquished bead

of PLA.

Also over extrusion has the effect of curling the edges up too. You will notice this as parts

looking bloated, like a balloon filled with too much air.

Depends also what temp you are printing at and so on. The hotter you print, the more the plastic

will cool before solidifying...so more warpage. I print 1st layer at 230 and rest at 220 Deg.

C.

Thanks for the tips Snowy. I'm going to tweak the bed height a little to see if I can get the big item I'm trying to print to stick better. The extrusion, in theory, should be ok. This filament has almost no variation in diameter. It's pegged at 2.85 wherever I measure.

[snowygrouch 1]

Also I have found that often its good to throw away the filament reel when it gets to about the last 2 meters (6 feet, haha). I once had a horrid jam because the last bit of filament had gone really brittle with age, because the radius of curvature is small in the filament right at the end of the reel on the inside - it doesnt enjoy going through the bowden where its almost straight and the filament actually snapped inside the bowden. That was a massive pain to sort out !

So I would recommend periodically checking just by bending a bit by hand to check its still nice and flexible before printing, and also chuck the reel away before you use up every single last bit. That was a reel of ultimaker grey filament that I had on the machine for about 2 months.

C.

[banana97 0]

Bill - try the disc method, it should work well with your model.

[billdempsey 0]

My latest print is a roller which will contain skateboard bearings to go on a steel rod for a filament cradle I designed. I'm liking the Ultimaker gold filament. Works well at 195C. Slightly higher if I crank the speed way up.

Has anyone tried a spray adhesive on the blue tape to keep long flat parts from curling up at the ends?

[billdempsey 0]

Bill - try the disc method, it should work well with your model.

I gave that a try, but the discs separated from the part. How many layers thick are the discs supposed to be?

[banana97 0]

Bill - try the disc method, it should work well with your model.

I gave that a try, but the discs separated from the part. How many layers thick are the discs supposed to be?

I used 0.2mm thick discs.

[smorloc 0]

I print 1st layer at 230 and rest at 220 Deg.

What is your technique for doing this? A plugin? Manually adjusting the temp during the print? Something else?

[msurunner 2]

He's doing that with KISSlicer, which allows for different first layer temps. Try downloading that gist I placed in the Cura section and place it in your plugins folder. Then keep the old speed and new speed the same and it should work the same.

[tomnagel 126]

To experiment with this, I think you can manually add commands to the Gcode file.

By heart, I think M104 S210 sets the temperature to 210 degrees. I've never tried it though.

[msurunner 2]

It does, the plugin in I referred to will input that command when it reaches the desired height as well as modify the speed if desired

[pablobell 0]

Whenever I need good adhesion I wipe the tape with a cloth with just plain alcohol (ethanol 96%). the PLA sticks so well that the tape will tear from the bed and not from the part. The only way of taking the tape out from the printed part is by submerging it in hot water.