Extruding Nylon

TheFerminator Wrote:
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> just soak the cardboard in warm water untill it is
> very soft. peel off what you can and scrub the
> rest off witha a sponge.

Yep, and if worse came to worse use Goo Gone (can buy small bottles at the Dollar Tree or get larger ones at Wal-Mart, etc...) as it is citrus based, smells like oranges and does a really good job.

That will get most of it off, but it still leaves small fibers imbedded in the plastic. This is usually fine but I want to spray paint the parts and the fibers make it look very ugly on the bottom. And about the drain cleaner, I will do everything outside and with adequate protection.

No matter what you use to disolve the cardboard you are going to either end up with wood fibers or pits where they used to be. If you want a smooth finish on the bottom I would add an extra layer or two on the bottom and sand/cut them off. Maybe you could print a crosshatched pattern first that could be peeled off of your actual part? I don't know how else you would remove the texture.

The fibers are really just a fuzz. I doubt you could even tell if there were pits. The bottom of the part should look exactly like the surface of the cardboard. I just picked up some battery acid from autozone today and I am going to try putting the parts in that. I will rinse the parts in a water bath and dispose of the acid properly. If this doesn't dissolve cardboard, I don't know what will.

Edited 1 time(s). Last edit at 09/10/2012 07:15PM by galaxyman7.

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I am a printrbot owner who refuses to pay for expensive filament anymore. I started using Nylon weed trimmer line, which is about a third of the price. Instructions are here:
[reprap.org]

Well I tried dissolving the cardboard, and it turns out that Nylon will oxidize in sulfuric acid. This makes a gooey coating around the part and ruins it. It figures huh? I think I just need to find something else the nylon will stick to that dissolves in water. I am going to try plaster next.

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I am a printrbot owner who refuses to pay for expensive filament anymore. I started using Nylon weed trimmer line, which is about a third of the price. Instructions are here:
[reprap.org]

Off the subject: I never knew who you were before but saw your Free Energy video a couple of months back and LMAO.

Haha that is my brother on the video. Ya that video got a lot of dislikes, possibly because people didn't get the sarcasm.

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I am a printrbot owner who refuses to pay for expensive filament anymore. I started using Nylon weed trimmer line, which is about a third of the price. Instructions are here:
[reprap.org]

I just tried plaster, and it failed miserabley. The plaster didn't stick to the cardboard as well as I thought.

Does printing a raft not allow you to remove the cardboard from the part? As far as other base materials are conserned you could try unfired clay. Once clay has dried it is very porous(some more so than others) and will easily disolve in water. I would try one from the stoneware category, they are the roughest and most porous. Earthenware and porcelain would probably work also.

Just add water to the clay(unless you get it already in a slip form), then pour it into a square mold and let it sit until dry. after printing break off most of the clay and soak your part in water to remove the rest. Some may remain in your part, but the particles should be small enough to not cause any issues. You can then recycle your clay for another print by soaking it in water.

This would be very similar to your plaster idea. I would make the slabs at least 1/4" thick so they aren't too fragile. you could also cut the clay into slabs, but I don't think this would give you a flat enough surface. It is hard to make a perfect cut in clay.

be careful not to get your Nylons mixed up :-)

their are several different types of Polyamide (PA6, PA6.6, PA11 &PA12) and they all have different melt temps from 180 to 240. also most are unplasticized.

KDI can offer a low melt temp Plasticized PA12 filament in natural or black, we would need to get a fair bit of interest before committing to a run as the raw materials are 4 times the cost of PLA plus a few other things too.

let us know what if you want?

Why would one want it plasticized?

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[www.hydraraptor.blogspot.com]

Ok well I came up with a solution for removing the cardboard that is fairly easy. I used a dremel tool with a fine wire brush attachment to sand off the cardboard. It seems like the wire brush doesn't damage the nylon, so I still have a nice surface finish underneath. And as long as you keep the nozzle height for the first layer above 0.3 mm or so, you shouldn't have to sand off too much cardboard. Make sure to wear safety glasses when using the dremel. I will update the video and the wiki for extruding Nylon.

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I am a printrbot owner who refuses to pay for expensive filament anymore. I started using Nylon weed trimmer line, which is about a third of the price. Instructions are here:
[reprap.org]

I'm getting really good results printing onto FRP (fiberglass reinforced paneling). It's formed with a polyester resin. Available at most hardware stores. Had some in the shop so I thought I'd try it out last night.

It's a sacraficial build surface as the nozzle semi melts the first layer into the FRP.

Running the nylon at 200C, and the bed at 60C.

First layer adhesion is really good, with no warping.

I throw the FRB sheet in the freezer right after the print finishes to aid in part removal.

Still testing but good results so far. Either getting the first layer to seperate from the print, or getting some small pieces of the panel stuck to the bottom, easily removed.

Edited 2 time(s). Last edit at 10/23/2012 08:02PM by Dirty Steve.

Not sure if you have considered it but a Arc stick welding oven would be a perfect place to store your nylon filament to keep it moisture free. You could possible even create your own. I also wonder if a food dehydrator would work or a room dehydrator + a mini fridge. Honestly, all of them will probably work well. Considering you can usually buy a food dehydrator for cheap at a thrift store or online, I would start there.

double post sorry.

Edited 1 time(s). Last edit at 10/24/2012 01:00AM by jzatopa.

I always suggest the Dollar Tree, or the like, for a large closet dehumidifer for a dollar and not only is it a dolar but it doesn't have any continuing cost like anything you have to plug in and run.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

@ Steve
Have you been printing with trimmer line or a pure nylon welding rod? If you are printing with trimmer line, I suggest raising the temperature of the bed and the nozzle, to 240 C and 100 C. I find that it will minimize warping quite a bit. As for the fiberglass, that is a good idea. I will try it out over winter break.

@galaxyman
I'm printing with trimmer line, I've found out that even 60 C makes the fiberglass panel too soft and the nylon warps the panel. Now printing without bed heat.

What ever the composition of the trimmer line I'm using, it kind of burns/scorches a any temp much higher than 220 C. Even at 200 C, the tiny amount of printed material that gets picked up by the edge of my nozzle will scorch and evenually drop/smears into the print. Have tried a couple different brands of trimmer line, temps vary but they all have a temperature where they seem to start boiling/cooking. Not from moisture in the line(oven baked), but the actual material itself. Printing at 10 C below that temperature. I do have some line that flows at 240 C but it's very sensative to temperature fluctuations.

With the fiberglass panel, this trimmer line REALLY stucks to it. I'm going to laminate a sheet of stainless steel to the back side of the fiberglass because I'm getting some panel warp just from the heat of the trimmer line and nozzle.

Can get fairly clean part removal with heat/cold cycling.

I recently got some of that red trimmer line from galaxyman7's sig and I must say it definitely extrudes quite well! But it is warping like crazy. I have printed onto blue tape and hairspray-coated kapton and it seems the first layers stick fine but then it just starts peeling after second or third layer.

Has anyone tried printing with a higher bed temperature? It seems to me the way to cut down on warping is to make sure the nylon stays soft longer, right? Because the problem I see is the nylon near the bottom of the bed is too flexible and so when the filament is added on top it cools too fast, shrinks, and conducts its stress more effectively through more layers. If we could make it cool slower the filament would "anneal" and thus be less stressed.

That is why I print it on card board. It sticks to it very well and keeps it from warping. Use that along with the "brim" and you should be fine. I do feel like printing at a higher temperature would be beneficial, both in making it warp less, and making the layers bond together better.

Edited 1 time(s). Last edit at 12/29/2012 05:41PM by galaxyman7.

Hi Galaxyman,

i've found some trimmer line thats 3.0mm in diameter, i've order some 0.5KG of it.. will give it a try with enough... ventilation

3.0mm fillament Nylon arrived, trimmer line

hp_

WOW, I have never used a trimmer that used that diameter of line. Mostly 0.65" but .120? The beastly trimmer that could handle that must weigh a ton.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

A few things. You said "No one wants to leave their oven on for 10 hours."

Why not? I left my Nylon in overnight at 180F and when I woke up, the oven had turned itself off. It seems to time out after maybe 16 hours. Ovens work by cycling on and off and so will have a very low duty cycle at just 180F considering it is insulated. In fact, your hair dryer was perhaps 1200 watts and just 120 volts, so less efficient, and probably used more power.

My often has a convection mode, which blows air.

Also - rice does not really work well to absorb moisture - that is a myth - sort of like saying Baking Soda will remove odors from your refrigerator. They are believable only because there is a little truth to them, but neither are effective.

The lowest cost desiccant is silica kitty litter.

[www.amazon.com]

I bake my media, and then store it in a large SKB gasket-sealed equipment case with some of that kitty litter.

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[www.matter-replicator.com]

I was also having this trouble of excessive moisture absorption after processing.

Finally, I was able to reduce the moisture absorption with the use of nanomaterials by 9%. Add to it, this also helps in very convenient injection molding by making the ejection very smoother. This is our inhouse developed product for PA6 processing.

I had good luck with fabric glued to glass run cold on this print. I have not yet tried a solid object:

[www.youtube.com]

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[www.matter-replicator.com]

I have been printing with nylon a few days and I used the backside of a new copper clad (PC board). It's basically fiberglass as it was a single sided board. It sticks well if it's heated a bit (50c to 75c) and the parts can be removed very easy with no residue.

@rsilvers, what type of fabric did you use?

iv been printing with nylon for a few days now, using just line trimmer at the moment on a glass bed without anytape...

Just been using UHU glue on the bed, smearing it on, PLA works beautifull, nylon stick very well, and abs also works well



Iv gone from restarting prints all the time to it printing right first time everytime.

UHU? LOL, that is glue stick you can find at the dollar tree. Bravo.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.