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General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: What size filament can we go down to? - 12 years ago
Actually if you keep Nylon below its breakdown temp of 300 C it won't emit any harmful chemicals. I run Nylon at 230 C and it sticks to itself very well. It is very hard to separate the layers. For bigger parts where the layers have more time to cool, you will want to print at a higher temperature. It doesn't actually weld the layers together, but suprisingly has almost the same strength. I thinkby galaxyman7 - General
Re: Absolute newbie questions - 12 years ago
Get a printrbot. I have one and it works great. It has a very quality hot end and extruder, a nice heated bed, all linear bearings, and overall a very compact design. The kit is only 500 dollars. However, they are still shipping kickstarter bots, so you will have to wait a while for it. Brook should put the kits in the store soon.by galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
Ok this is weird. I got the weed wacker line today, which is supposed to be made from nylon, and it still extrudes fine at 230C! It acts exactly like the last stuff I had. It oozes like crazy, and warps quite a bit, but other than that it seems to be fine! I am going to get another nozzle with a longer orifice to fix the ooze, and get some perfboard to stop the warping. Maybe whatever is mixedby galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
I do not understand that either. Maybe the insulator does get soft, but judging by the pics of the hotend, most of the force on the hotend is held up by the two threaded rods. That way the PTFE doesn't deform, instead it just acts like a filament guide. Anyways, do you think it would even be possible to extrude plastic at 250 C? Would the force required be too great?by galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
Now that I think about it, the guy on instructables said that he printed at 320 C, on a cold bed. In his instructable he said "There are of course differences in how we print with NYLON as opposed to ABS. One of the main differences, is that we will "melt" ABS, PLA and PET but we will "cold extrude" Nylon, Nylon polymers, Acrylic and polycarbonate. " So this is an average temperature of arouby galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
Oh and I would use an oven thermometer to get it up to the right temperature. Hopefully the heat from the hotend and heated bed will keep it at the right temperature. Either that or I could use some kind of toaster oven thermostat ect.by galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
Interesting, I don't want to change my hotend preferably, so maybe I could add a heatsink and a fan above the hot end? How much could I lower the temperature of the PEEK if I had the optimum heat sink? Another option: I was also going to make a heated chamber for it anyways, but I am not sure how hot that can get. I guess if I get it up to 190 C Then I could actually stay in the range of the melby galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
It does float, which leads me to believe it is polypropylene, not nylon. Nylon has a density that is higher than water. Anyways I have already ordered some nylon line, so I will need an enclosed build chamber with a hood for that, if it does indeed need to be above 300 C to extrude. Not sure if my hot end can go that high actually. It has a PEEK insulator, which has a melting point of 340 C.by galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
Here is the safety sheet for nylon: It says that nylon emits HCn at 300 C. I am extruding it at only 220 C. I don't even think my extruder can get up to 300 C. So I think its perfectly safe to print.by galaxyman7 - General
Re: Printing with weed wacker line - 12 years ago
What about a solder fume extractor? That should work right? Right now I have a fan going next to the machine which blows the fumes out the window.by galaxyman7 - General
Printing with weed wacker line - 12 years ago
Hey guys, I got my printrbot a while ago, and I decided to test out some weed wacker line from ACE hardware. I am pretty sure it is NYLON, but it could also be polypropylene. Not really sure since I am extruding it at 225 C. It was around 5 bucks for a spool. Not sure how much it is compared to ABS, but it doesn't matter since I will be buying it in bulk for much cheaper here: This is arouby galaxyman7 - General
Re: Extruding Nylon - 13 years ago
Just wanted to update this thread. I just saw an instructable on how to print with Nylon here: The results look amazing. I hope more people try this as it looks extremely useful.by galaxyman7 - General
Re: Polar arm based on frog-leg - 13 years ago
Funny thing is I have ordered a printrbot too. It is also my first 3-d printer. However, I do have a lot of experience with DIY CNC machines. I really think that this design is the way to go for a cheap 3d printer, considering there is no cutting force like on a milling machine. This means there does not need to be much support structure, because the acceleration of the printing head can be prediby galaxyman7 - Polar Machines, SCARA, Robot Arms
Re: 2DOF Servo Arm + Stepper X-axis - 13 years ago
Well i haven't been on the forums for a LONG time, due to school. Its good to see that people are fooling around with the robotic arm idea still. If you don't know what I'm talking about search for "robotic arm" on the wiki. I just ordered a printrbot, so I can actually make some of the parts for the robotic arm that I couldn't before. I think the threaded rod in this design makes it very accuratby galaxyman7 - Developers
using dc motors instead of steppers/servos - 13 years ago
I just saw this youtube video and thought it would be good to post it here. It looks like a very easy way to make an accurate servo out of any dc motor. Of course, I would rather use an interrupter type encoder instead of a reflective. You can get a transmitter, reciever pair that comes in one package for very cheap. It produces a suprisingly clean signal with the comparator. This would makeby galaxyman7 - General
Re: Extruding Nylon - 14 years ago
Warping has been fixed with other plastics, so I am pretty sure we can find a solution for nylon. Maybe use perf board to hold down the part? It has more of a mechanical grip rather than chemical bond. As for the note about waiting in between layers, I wonder why that is. Is it a cooling problem? That can be fixed with a mounted fan. I am sure we can work with nylon if people just experiment withby galaxyman7 - General
Re: Extruding Nylon - 14 years ago
I have not seen anyone that has printed something from nylon. This is probably because no one has tried drying the nylon first. So this is "cutting edge" stuff. I dont have a printer, so the first step is getting other people to try it.by galaxyman7 - General
Re: Extruding Nylon - 14 years ago
Great, this weekend I will dry 10 ft for you. Will that be enough?by galaxyman7 - General
Re: Extruding Nylon - 14 years ago
Unfortunately no one has taken up my offer for free nylon filament. I think it is because not many people have the ability to extrude 1.75mm filament. I am sure it will work, and if I can find 3mm nylon then people might start to try it.by galaxyman7 - General
Re: Alternative to timing belts - 14 years ago
Belts really aren't that expensive. Just search for "small parts inc" seller on amazon. They carry belts and pulleys there for ridiculously cheap prices. I saw a 21 inch belt for 28 cents, and pulleys for 50 cents. Just make sure you match up the pitches of the pulley and belt.by galaxyman7 - Mechanics
Re: Threaded polar arm study - 14 years ago
I just worked though the math to figure out how to move the arm so that it will always stay the same distance above the ground, making a straight line. Turns out it is very easy if you set up the positions of the motor and nut right. The equation for making a straight line at a fixed distance above the ground is: Z=C1( ( -(d1)^2 + h^2 + (A1-B1)^2 ) / (2*h*(A1-B1) ) - C2( ( -(d2)^2 + h^2 + (B2-A2by galaxyman7 - Polar Machines, SCARA, Robot Arms
Re: nylon - 14 years ago
Go to reprap.org/nylon for information on extruding nylon.by galaxyman7 - Plastic Extruder Working Group
Re: Threaded polar arm study - 14 years ago
Having gears that are made by the reprap will introduce some backlash. Do you have an idea of how much it will be? I suppose that can be fixed within the software by making the motor take up the backlash when it changes directions. That is what I do with my cnc milling machine and it works great. You could also get some gears from amazon here: They have great prices on materials, belts, pulleysby galaxyman7 - Polar Machines, SCARA, Robot Arms
Re: Threaded polar arm study - 14 years ago
Where do you get the first one? It looks like it crimps on? I have used the hose clamp and it still slipped off the shaft.by galaxyman7 - Polar Machines, SCARA, Robot Arms
Re: Threaded polar arm study - 14 years ago
I like the couplings. However, I assume those wouldn't support forces along the shaft. It would probably just slip off. There might be a way to put a screw through the shaft and the tube to hold it there. Or maybe use a shaft collar on each end to hold it there. It might rip if you puncture the tubing though.by galaxyman7 - Polar Machines, SCARA, Robot Arms
Re: Threaded polar arm study - 14 years ago
Well I am really glad to have someone to work with on this. Usually if I work on something by myself I never get it done due to lack of motivation. One thing I found to be a huge pain was getting the motor to rotate at a constant speed. I really think a flexible coupling is needed to reduce binding of the threaded rod. Using rubber hose might work, but I have had very little luck doing that. Do yby galaxyman7 - Polar Machines, SCARA, Robot Arms
Extruding Nylon - 14 years ago
Hey, I already posted this in the general section, but I figured it belonged here. I just made a wiki entry on how to prepare nylon trimmer line for extruding here: The pictures only show a little bit of trimmer line, but a whole spool can be dried at once. Also, I have some extra dried line if anybody wants it. It is 1.7mm diameter, and I will ship it to you for free. I just want to see someonby galaxyman7 - Polymer Working Group
Re: Extruding Nylon - 14 years ago
I just extruded some nylon. Here are some pictures. The first ones are without drying, the second are with drying. You can see that drying it gets rid of all the bubbles and makes it smooth. These were taken with a usb microscope. Does anyone want any nylon line? I will ship it for free. I just want to see someone try it out on an extruder.by galaxyman7 - General
Re: Extruding Nylon - 14 years ago
It will slowly absorb more water after being dried. As long as it is kept in a sealed container you won't have any problems. Look at the post above for instructions. As for 3mm line, I have not seen any. The stuff on amazon is around 2 mm, and the largest I have seen is around 2.5 mm.by galaxyman7 - General
Re: Extruding Nylon - 14 years ago
Yes, the filament is flexible enough. It is only 1.7mm, so even after drying it is more flexible than 3mm ABS filament. I suspect that if you over dry it, it might not. You can always reverse the process by leaving it out or even soaking it in water.by galaxyman7 - General