printing with nylon

[Eaglezsoar]

Invite us down to Florida when the Crawfish is ready.

[dbarrans]

I'm just waiting for that pot to implode. If I knew how big it was, I'd have calculated how much force is pushing in on it.

Oh, what the heck. Let's call it 12" diameter and 12" tall. Sides of the pot add up to about 452 sq. inches, plus another 113 sq. inches for the bottom. Won't count the top, since that's not part of the pot. That makes 565 sq. inches times 29 lbs/sq. inch, which is 16385 pounds? Is that thing still holding?

Why does that number almost sound familiar? I've been writing software too long.

- dan

[cambo3d]

its been under vacuum for about 12 hrs now no problems and its still holding vacuum.

vacuum chamber works really well for what it is, its not thin metal and has fairly thick lid.

as far as the idea i'm using for, still testing.

[dbarrans]

What was I thinking? I got my units mixed up. 29 inches of mercury isn't the same as 29 lbs./sq. inch.

OK, let's try that again. 565 times 14.24 lbs./sq. inch is about 8046 pounds. I feel better now.

- dan

[Generic Default]

Pentagon shaped trimmer line seems to work just as well as round line. I'm printing some magnetic arm cups right now and they're turning out nicely. No problems with the feed wheels or extruder.

[Durandal]

What did you use for the vacuum pot? The pump looks like a harbor freight model but I don't recognize the pot.

[cambo3d]

What did you use for the vacuum pot? The pump looks like a harbor freight model but I don't recognize the pot.

i just bought a ready made one off of ebay. My goal here was to test my idea out and not worry about finding parts to make the vacuum chamber.

as far as the idea, im not getting great results, the vacuum chamber works great to hold a vacuum. yesterday I took the nylon out to try a test print and it still had moisture in it after being in the chamber for 3 days.

in the first test the vacuum pump was shut off and the chamber sealed to hold vacuum. After 3 days I opened it and the humidity inside seem more than the outside. My guess is that the humidity had no where to go.

im gonna do this test again but time keep the vacuum on to see what the results are. maybe that will cycle that humid air out??

[Broose]

Back to dehumidifiers... I've been storing my spools, including the nylon, in jumbo hefty bags with desicant and they seem to be reasonably dry. I picked these up at BJ's Wholesale Club. I wonder how well they will work? I like the fact that they have moisture indicators and you can recharge them in the microwave.

[lordbinky]

I had difficulty deciding between the toxic blue to pink indicating silica and the orange to green nontoxic silica. I just really like cobalt blue and I'm not going to eat it.... Anyways, i can't microwave the ones I got because they have a metal container so I have to use the over. Sounds convenient though.

As for Cambo3d's experiment, I'm excited to see the result of leaving the vacuum pump on longer. Have you considered that you may have to flush the chamber with dry air and just repeat the process X times after letting it sit at the stable vacuum some time, like an hour?

[Flateric]

There is a product called Dry-z-air.

My father in the RV business used to swear by the stuff. I now know why.

It will literally fill a cup with water if sitting in a cup overnight.

The downside is that it requires careful handling because you can then spill that water easily when inside you container. But the bigger danger my father explains is that if you spill the product or the water from the product on anything that spot where it spilled no matter how much you rinse, soap, clean, sponge, dry and rinse again will never, ever by a dry spot again. It will be permanently moistened.

But literally sucks the water out of the air. But much more so than the little packs the filament ships with.

http://www.walmart.ca/en/ip/dri-z-air-pot/10024706

http://www.drizair.com/

http://www.canadiantire.ca/AST/browse/5 ... ?locale=en

[Generic Default]

I've been testing ways to keep the nylon dry, and so far the best thing I've come up with is to dry it out in an over for a few hours (open the oven door to let out the humidity every hour or so) then put it in a plastic food container with an air tight lid. I drilled a small hole in the lid about the size of the filament so that the extruder can pull the trimmer line directly out of the [almost] airtight container. Keep a few bags of desiccant inside to make sure it doesn't absorb as much water. I bought the food container set at Walmart for less than $7.

If you leave the trimmer line spool in the open, expect to have to dry it out about once a week. There is a huge difference in print quality between dry and wet nylon. You can tell how much moisture the trimmer line has absorbed by the surface. If it is more of a matte color, it's dry. If it looks glossy and has a more vibrant color, it's saturated.