Nylon Filament

[basfud]

You know, I'm going to try that one more time. The last time I did it with a large part (7.5" x 7.5" x 6.0") it stayed stuck to the tape but pulled the tape off of the glass. So the net result was still a part that came up. Maybe I'll wrap the tape around the edges of the glass. That might help.

Whoa, that's some serious warping then. Did you try printing the nylon in a heated chamber? Improvising something quickly to close the printer, so that the build chamber heats up to 30-40 degC, to minimize model deformation?

[RobH2]

Yes, I did create a chamber and used a heated bed but I must still be getting a draft. I did read about using PVA glue on the glass so I tried that. It worked like a champ, only one problem, as the part dried, it cracked the expensive borosilicate glass. Really, here's a photo:

PVA.jpg

So what I tried next was wood. I used a piece that was 3/4 inch thick and nice and smooth. That worked well and since I have autoleveling set up it went smoothly. That actually worked the best. I'm have enough 618 for one more print so I'm trying to use it up. I've switched to Bridge Nylon and it's much more friendly.

[basfud]

Yes, I did create a chamber and used a heated bed but I must still be getting a draft. I did read about using PVA glue on the glass so I tried that. It worked like a champ, only one problem, as the part dried, it cracked the expensive borosilicate glass.

Whoa :O

I've never printed things that large from Nylon, but I used to un-tension ABS parts mid-print. I used a hairdryer to rapidly raise the temperature of the whole model and chamber, to make it approach the lower glass transition temperature of nylon (did it by the thumb), then let it cool in normal ambient temperature of the print chamber. This may help.

[American 3D Printing]

As I type this I am building a part that's about 250mm x 90mm - pretty big. Even with glue on an acrylic bed, 618 wants to curl at the corners. So we applied a trick we've learned when designing parts to be built with nylon. Basically you build a brim straight out from all the edges, in this case 10mm in all directions. Unlike a traditional raft that goes underneath like Makerbot wants to do when you slice it with the raft box called out on the slice, this is actually part of the model itself, added in Solidworks to the original model that was designed in Solidworks. Unlike the brim that slicing engines like Slic3r and Voxelizer add, you can make this as thick or thin as you want. Since we are slicing at 0.2mm layer thickness, we made the brim on this part 0.4mm so it would be 2 layers thick.

[curious aardvark]

ah - now that's clever.

@robh2

So what I tried next was wood. I used a piece that was 3/4 inch thick and nice and smooth. That worked well and since I have autoleveling set up it went smoothly. That actually worked the best. I'm have enough 618 for one more print so I'm trying to use it up. I've switched to Bridge Nylon and it's much more friendly.

wood is what I understood taulman recommend - at leats they did last time I went through the 618 specs (got a pound, haven't tried it yet).
So are you using a flashforge - and if so how did you set the autolevelling thing up ?
Very interested in that.

[Roxy]

@robh2

So are you using a flashforge - and if so how did you set the autolevelling thing up ?
Very interested in that.

I'm curious too. Can you take some detailed pictures?

[RobH2]

My pound of 618 was primarily used up proving that it is nearly impossible to print large items with 618. I did figure out what Jeff has learned, that if you put something around the corners they might stay down better. I used quarter sized thin (2mm tall) cylinders. That's what held so well with PVA that I cracked my glass.

So next I tried wood. I've attached a photo of that. IT had different tabs. I called them "X-Tabs" when I labeled my 3d files. Since (with all the fantastic help from Roxy) I had autolevel working pretty well, I just put the wood on, ran autolevel and printed. It stuck. It was my first successful print. The other photo shows the warp I was fighting.

That stain you see on the wood was another attempt to salvage a print. It started to lift so I put some superglue under the lift and held it down, hoping to reattach it. That didn't work. Nylon, as I suspected, won't stick to superglue. But wood and fingers sure do. I had to use an xacto blade to get my finger off of the wood. That was kind of hilarious as the print continued to run. I wish I had a video of that.

Nylon618Success.jpg NylonWarp.jpg

Edit: Oh yea, 'curious aardvark', I have a Makerfarm Prusa i3 8" printer. I think it's in my signature. Once you get it going autolevel is fantastic. Right Roxy?

[Roxy]

I'm curious too. Can you take some detailed pictures?

Edit: Oh yea, 'curious aardvark', I have a Makerfarm Prusa i3 8" printer. I think it's in my signature. Once you get it going autolevel is fantastic. Right Roxy?

Yes, Auto Bed Leveling solved a world of problems for me. And made it much easier to print things! But I wanted to see detailed pictures of how your servo is attached and how the probe leg is shaped.

[RobH2]

Yes, Auto Bed Leveling solved a world of problems for me. And made it much easier to print things! But I wanted to see detailed pictures of how your servo is attached and how the probe leg is shaped.

Oh, misunderstood. Here are a few photos. The white stuff you see is Sugru. I used it to keep the wires from flexing and breaking off. Nothing worse than losing power on that servo and getting a head crash. It's not pretty but it works well. The piece of copper wire you see sticking out helps torque the sensor over so it's more parallel with the bed. The side of my hotend carriage is a bit angled and I needed to compensate for that. I know it looks jury rigged, but, it works well.

AL01.jpg AL02.jpg AL03.jpg AL04.jpg AL05.jpg

[Geoff]

It's amazing how much climate will affect things, I literally have no chamber, have no auto level on this thing, and yes sure ive repaired and rebuilt and recalibrated it more times than I can remember, it will print raftless on the kapton and stick there forever, nylon or ABS..

man that sucks about the glass cracking...

I am printing off my Prusa parts, so far so good and yeah after replacing a mainboard and drivers my flashforge is ready for one more haul to make its replacement
lolz.JPG