Nylon and PrintBite

I've been experimenting with nylon trimmer string. It prints beautifully but I can't get it to adhere to PrintBite. I've tried bed temperatures from 65 to 110 degrees and hot end temperatures from 235 to 250. The highest I've been able to print an object is 4mm and most failures were closer to 1mm.

Does anyone have any tips on adhesion techniques for nylon on PrintBite? Will using an ABS slurry or purple glue have an adverse effect on PrintBite?

Nylon trimmer line is going to be unpredicatble material as we dont know what else is in it, but lets treat is as nylon for now. I have heard of others printing such material no issues onto printbite so its anyone guess with this stuff.

Nylon is a high temp material, so I would suggest going higher with your nozzle temp, 260 - 270, if only for your bottom layer. Bed sounds hot enough.

If this fails, then give a substrate a go. 3D nylon such as taulman etc will stick to PrintBite without too much problem.

It goes without saying the above suggestions presume you have a clean bed.

Use bakelite sheet instead, 80 degrees is best for the bed and 260 for the hotend.

Edited 1 time(s). Last edit at 08/08/2016 07:49PM by ggherbaz.

I regularly print trimmer line. Cold bed, with glue stick on glass. Are you baking the trimmer line before printing? It holds alot of moisture, and even after baking, it will only stay dry for about a day or so. Printing at 265c. Printing with a brim definitely helps reduce warping.

Edited 1 time(s). Last edit at 08/09/2016 10:14AM by Dirty Steve.

I had a little better success yesterday by doing the following:

• Increasing the hotend temp to 270 degrees
• Setting the bed temp to 115 degrees
• Adding small pads on the ends
• Using a 9mm brim

The print still failed, but it stayed attached longer.

Using another print surface isn't a viable option as the PrintBite is glued to the aluminum build plate.

When using an ali plate of any substantial thickness consider if there may be a temp differential between the top surface and your thermistor location.

An IR temp gun (if you have one) might help by providing a top surface temp indication for comparison to the given thermistor based reading. Or a multimeter with a thermocouple attachment.

HTH

I made a small change in the effector height, moving it .05mm closer to the bed. The first layer height is now slightly less than expected, .22mm instead of .25mm. The prints appear to be sticking nicely. Here's a short video of the prints: [vidmg.photobucket.com]

They are Module .8 herringbone gears, 15 and 120 teeth. Layer height is .07mm. Brim is 9mm and isn't very easy to remove cleanly.

@etfrench

That sounds like a win. And within pretty respectable engineering tolerances. Well done for perservering. Key is getting temps and bottom layer height "just right".

I fancy your chances without the brim and pads next

Adhesion of trimmer line to paint scotch (with paper like surface) is good, but adhesion of scotch itself (to bed) is not so good. Sometimes delamination occurs.

I dunno about trimmer line (why???), but I've had great success with Taulman 645 and Bridge using Printbite. I start the bed at 95C and increase to 105C after the first layer, with 265C nozzle temp, with 30 rounds of skirt lines. With the Bridge filament I get absolutely no warping whatsoever, and with the 645 the warping is very minimal.

One thing to note, Printbite needs to be "broken in" for nylon. As best I can tell the mechanism on Printbite is that it expands and opens ridges in the print surface to increase bonding area. You gotta get some nylon deposited into those ridges, which means your first few prints may not turn out, but afterward there is a thin layer of nylon embedded in the surface that aids in sticking to the bed. The stuff looks like a polarized lens.. I wonder what it actually is.