Extruding Nylon

yeah it works very well, alot are using this method already, it just washes off with water when ur finished and is non toxic and not messy to work with

I haven't tried printing with nylon yet, but I also use glue stick for ABS parts and it works VERY well. I print the first layer at 115C and drop the bed temp to 85C for the rest of the print and I get no warping. Once the print is done, at about 50C the parts pop off by themselves. At first I was using UHU Glue stick but after I ran out I bought a stick of Elmers Glue and I find that it works a bit better. Elmers Glue stick is less gooey than UHU stick and can be applied very smoothly to glass. The bottom surface finish on these parts is beautiful.

However, one thing I have noticed is that glue stick has to be reapplied approximately every 48hrs of printing as it's adhesive properties start to wear out due to the prolonged heating.

Eric

I wonder which part is the part helping in the printing? More than likely one, or possibly two, of the materials that are going into the glue sticks is what is helping and the rest come along for the ride.

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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.

I also wondered about this. I looked on Wiki and I found This. It doesn't really clear things up though as the component substances do not seem to be found in ABS so I am not sure how to explain the adhesion

Eric

CAPROLACTAM-ε <5% This is an acid.
HYDROGEN PEROXIDE SOLUTION <1% so less than what we find in any department store for cuts and bruises.
SODIUM HYDROXIDE <1% and I bet this is the baby as it is lye which is caustic so I bet it melts the plastic to the table however slightly but just enough to affix it.

After reading I suspect the tag along is the Hydrogen Peroxide and the two acid/caustic chemicals is what is doing the magic trick. Possibly they have a synergestic effect.

Edited 1 time(s). Last edit at 08/11/2013 04:22PM by Dark Alchemist.

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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.

Great insight! I totally overlooked all that. As you mentioned, Sodium Hydroxide is caustic and used to dissolve PLA parts, so I imagine that the Glue stick method would work for PLA as well. However, I recall that people use NaOH to dissolve PLA support material from ABS prints, so presumably this chemical does not have much of an effect on ABS (?). Not sure. You're right though, it's probably the combination of chemicals that creates the adhesion. It would make for an interesting experiment to isolate these active chemicals and try printing with a more concentrated solution applied to the bed.

Another important feature of this glue stick method is the fact that is sticks well when hot, but releases the part when cooled to about 35C to 65C depending on the initial adhesion. For example, if you squash the first layer, the part won't pop off until the bed reaches about 40C. There must be some critical temperature determined by the concentration of chemicals in the glue, the first layer thickness, first layer print speed, etc. that governs this behavior.

Eric

The first chemical is from 1% to 5% so if it plays a higher role in the adhesion then each stick would/could stick better or worse than the other. I lay odds it is the Lye more than anything and the US govt took Red Devil Lye off the shelves (home made soap makers are ticked at that) due to all of the heat they put on the manufacturer because it is one of the ingredients in the illegal drug Meth.

I know we can order Lye over the internet and it would make for a good experiment to see how that would work by itself in various strengths.

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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 while back I was trying to find lye to experiment with dissolving PLA but I couldn't find it anywhere. I live in Canada so I am not sure if the chemical is banned here but I looked at all the stores that were likely to carry it and I found nothing. Even if it isn't banned here, it is not common.

If you were to order it over the internet, would you order it from out of the country? I imagine there may be some customs issues...

Also, it would be great if we had some chemists in RepRap who could explain the "critical temperature" of the glue stick adhesive. What makes the glue stick method so effective is how significantly the adhesion strength is affected by temperature. If you print on Kapton, the print sticks fairly well at 120C but is difficult to release at ambient. On the other hand, glue stick adheres better than Kapton at 120C but the part pops off by itself at temperatures above ambient.

This "permanent-sticking" problem is much greater when you print ABS on an acrylic bed. Since acrylic is a component of ABS and thermoplastics adhere to themselves very well, ABS sticks very well to acrylic. However, printing ABS at above 200C is enough for it to permanently fuse to the acrylic bed. The key here is that the hot ABS is physically manipulating the acrylic bed essentially welding itself onto the bed. At the point of contact between the hot ABS and the cold acrylic bed, heat is transferred to the bed and the acrylic is heated beyond its Tg (glass transition temp.) so it fuses with the ABS exiting the nozzle.

On the other hand, when you print on glass covered with a layer of glue stick, presumably the caustic properties of Lye act to hold the extruded ABS to the glass sheet, with no direct interaction between the ABS and the glass. Think of it as the difference between welding and soldering. When you print on acrylic, you are welding the ABS to the acrylic bed, whereas when you print on glue stick applied to glass, the active chemicals in glue stick act as the solder, forming a bond between the extruded plastic and the glass bed.

Just my 2 cents

Eric

Apparently it is not illegal to order it over the internet and I found it easily enough but what they did was take it out of the Wal-Mart type stores to slow down the meth labs. In the USA it is not a controlled substance so here there is no fear of purchasing it because frankly I was wanting some to make some homemade soap (lye soap is really the best kind for really grimy dirt) when I ran into why I could no longer purchase it in the local stores.


"the active chemicals in glue stick act as the solder, forming a bond between the extruded plastic and the glass bed. "

That is exactly what I was getting at and it does make logical sense. Plastic on plastic they would weld together but plastic to glass the glass cannot be welded to by the plastic beyond a light adhesion.

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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.

What's the other 93% made up of? You may be right, it may be the trace substances in the formula, but it could also be the other 93% of stuff in there.

The temperature sensitivity of the adhesion sounds more like a mechanical property change than a chemical reaction.

I am definitely with you on that, the difference between "welding" and "soldering" makes sense and seems to explains the difference in the adhesive qualities of each method.

Currently, plain glue stick is more than enough for my ABS prints, but I am not sure how much success people are having with printing Nylon using this method. Assuming that the relation between adhesion strength and lye concentration is linear, we could theoretically continue to increase the concentration until we get enough adhesion to completely eliminate Nylon warping. I really need to get my hands on some of that Taulman Nylon to test this out!

Also, I think we have quite a few meth labs in Canada as well so there may be the same restrictions here. I think I checked Walmart and found nothing

Eric

I am also curious about what the other 93% is composed of. I imagine that it is just extra "bulk" (much like starch in PLA) and likely does not play a role in adhesion but simply dilutes the active chemicals to provide the desired amount of adhesion. That's just my guess. The Wiki article is not very informative but I am sure that this info can be found on the glue stick packaging. I bought my glue sticks individually and unfortunately they were not labeled for individual sale.

Eric

The other 93% I figure is what makes it a stick or basically binding agents.

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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.

guys im having very good success with printing with Nylon and a cold bed using the uhu glue stick, bonds every time


how ever
Depending on the print
I get warping issue, i see this less when i print a skirt the same layer height as the print, but i hate doing this as i dont like to waste, but a single wall one is not bad.

i thinking its time to enclose my entire printer, I dont have a heated bed, can you think of anything else i can try to get it to warp less?
I also get delamination issues unless i print with a hi skirt...

I personally find it easier to print with trimmer line over taulman 618..
I use about 260c 265c most of the time.

What trimmer line in particular are you using that you prefer?

nechaus,

why do you have less warping when you print a skirt ?
afaik, skirt is far from print ... so I don't understand how this helps with warping ...

thanks,
mihai

nechaus Wrote:
-------------------------------------------------------
> I get warping issue, i see this less when i print
> a skirt the same layer height as the print, but i
> hate doing this as i dont like to waste, but a
> single wall one is not bad.

Self printing thermal chamber ? A few people have played with this before, probably captures and keeps hot air from the printbed.

mihai Wrote:
-------------------------------------------------------
> nechaus,
>
> why do you have less warping when you print a
> skirt ?
> afaik, skirt is far from print ... so I don't
> understand how this helps with warping ...

With Slic3r you can use the *brim* feature to better hold you print...

Here you can see *brim* at work with black polyamide (aka Nylon).

Caution: it is boring and I am the one commercially responsible for that.

Bye
Davide

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no toys here...sorry

3ntrlab Wrote:
-------------------------------------------------------
> mihai Wrote:
> --------------------------------------------------
> -----
> > nechaus,
> >
> > why do you have less warping when you print a
> > skirt ?
> > afaik, skirt is far from print ... so I don't
> > understand how this helps with warping ...
>
> With Slic3r you can use the *brim* feature to
> better hold you print...
>
> He
> re you can see *brim* at work with black polyamide
> (aka Nylon).
>
> Caution: it is boring and I am the one
> commercially responsible for that.
>
> Bye
> Davide




That is good to know thank you very much, iv never tried that feature, i only just updated my slic3r version...


I noticed i had to also turn up retraction by 2mm to get it to function better,

the original post said "guys im having very good success with printing with Nylon and a cold bed ..."

the bed is cold ... so nothing to capture ...


cannonpr Wrote:
-------------------------------------------------------
> Self printing thermal chamber ? A few people have
> played with this before, probably captures and
> keeps hot air from the printbed.

it captures the heat from the nozel and the plastic its self.

I understand that nylon needs to be printed onto a celluose based bed to get good adhesion, materials like wood, fine fiberboard, and in some cases people have used denim cloth attached to the bed with an artists spray mount glue. Some of the fiberous ceiling tiles have also been cited. I have just ordered 3lb of weed wacker nylob from amazon for $18 To try this out, i have a machine with dual qu-bd 24v extruders, so i can get up to high temps.

just as a note I had to stop printing with the nylon trimmer line ive been using. I live on a boat and my printer is in the boat. Nylon emits cyanide above certain tempratures and I started getting increasing levels of nausea and head ache's the more i printed. Im assuming that i was building up toxicity levels in my system and until i get a venting system installed my experiments are over.

people from instructable & taulman have made some experiments regarding the emissions of hydrogen cyanide (hcn):

[www.instructables.com]

conclusion:

"So? How much HCN did you measure while actually printing?
3D Printing ABS from various 3D Printing material suppliers in China, the EU and US = None
3D Printing Nylon from taulman3D 3D Printing material supplier in the US = None
Two brands of Trimmer or weed-whacker Line mfg in the US = .1ppm"

"The international (OSHA NIOSH ACGIH) maximum allowable exposure to HCN is 4.7ppm"

"HCN is considered lethal at >30ppm"

the amount of outgassing of whatever toxic chemical it was is unknown and it did take about a month of pretty steady printing to cause adverse reactions. also what is emited realy depends on the type of nylon its self. I believe if i purchased some taulman nylon i wouldnt have the problem.
I also accept that my reaction may have been pshycosomatic from my infered knowledge and the rather pungent oder the trimmer line i was using put out.

RBisping Wrote:
-------------------------------------------------------
> the amount of outgassing of whatever toxic
> chemical it was is unknown and it did take about a
> month of pretty steady printing to cause adverse
> reactions. also what is emited realy depends on
> the type of nylon its self. I believe if i
> purchased some taulman nylon i wouldnt have the
> problem.
> I also accept that my reaction may have been
> pshycosomatic from my infered knowledge and the
> rather pungent oder the trimmer line i was using
> put out.
Did it smell like burning a clear empty plastic BIC pen?

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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.

i cant realy say what it smelled like.

I get headachs from pla, abs, nylon if im really close to the printer, the sound of the motors is also annoying..

I like the idea of a heated build chamber so it will also reduce sound, but really i want the motors on the outside.. not sure what to do yet, maybe enclose the motors in their own compartments

Sorry to bump this thread, but your symptoms sound like carbon monoxide poisoning more than anything else. Do you run a generator on your boat? Found your post when I searched for tips on nylon printing, and it bothered me so much that I registered so I could post this question.