Thank you for the tests, HaniC. You proved that a printing resolution of 0.1mm isn't the end of the world. As for the vibrations from full stepping, those 28BYJ-48 are so small that I don't think it will be a problem because of their low mass. aduy, we can further lower the price by either doing our own electronics or using another Arduino. Even at 20 bucks, it's too expensive if we can get awayby Yvan256 - General
HaniC Wrote: > Build Volume > My build volume goal is 120mm x 100mm x 100mm. > > Also FYI some guy on YouTube has experimented with > building a small linear stage using cd/dvd rom > parts. This concept provides some food for > thought... Searching for "Xbox worm motor" (or "PS2 worm motor", etc) gives a lot of low-cost results, there's some people selling more completeby Yvan256 - General
Crazy idea but… rack and pinion? I've made some tests with a toothed gear and simply pressing the gear against a ruler with a cork backing and it moved fast enough with plenty of torque, at least in my opinion. It can move the ruler with two NEMA17 motors on it, probably more than enough weight for a first test, the stepping rate could be increased once the printer is built. It's more than decentby Yvan256 - General
I forgot about half-stepping, so that would mean 0.13089969389957mm divided by 2 equals 0.06544984694979mm per step. Half-stepping means we could use unipolar motors and ultra-cheap stepper drivers. Worst case scenario we need to use full step drive to get more torque and are back at 0.13089969389957mm per step.by Yvan256 - General
HaniC Wrote: ------------------------------------------------------- > The NEMA17 sized motors seem to be in more demand > than the NEMA14 size and the 1.8 degree type again > more prevalent than the 0.9degree. Both factors I > believe are affecting the pricing. Are we trying to get smaller motors or cheaper ones? If the target is price then we should be targeting NEMA17, 1.8 degreesby Yvan256 - General
After reading about servo motors on wikipedia, it seems there's a lot of types of servos but the low-cost ones would be useless for a 3D printer: "Simple servomotors may use resistive potentiometers as their position encoder. These are only used at the very simplest and cheapest level, and are in close competition with stepper motors. They suffer from wear and electrical noise in the potentiometby Yvan256 - General
HaniC Wrote: ------------------------------------------------------- > I've started trying to source a >10N.cm, 0.9degree nema 14. This should give the necessary speed, torque and resolution when half stepping. Best price so far is about $7. I'm certain I get it to sub $5. Can you give us more details?by Yvan256 - General
I've also given up on those 28BYJ-48, at least in using them as regular step motors. I've tried to make them go forward 85 steps, pause, (repeat 5 times) and then backward 425 steps and it can't even do that properly. I'm not even talking about the gear backlash, after a dozen runs of that sequence there's an increasing positioning error… it's madness! I'll keep the three I have for other projecby Yvan256 - General
AFAIK Tantillus uses regular NEMA17 motors, I was only suggesting a modified, lower-cost Tantillus model that would use those 28BYJ-48 motors. If you were asking about my tests, I didn't eliminate the backlash at all. edit: what about trying the 12V version of that same motor? It should be stronger and/or able to be driven at much higher speeds.by Yvan256 - General
Nice little design, aduy. I've received three of these 28BYJ-48 motors too, ordered from China via eBay, and mine aren't 2048 steps either. If you run them in full step drive, they're still pretty powerful though. I don't know if they're powerful enough for a delta bot, but I'm thinking something like a Tantillus could be made with them. Wouldn't using them in a delta reprap eliminate backlashby Yvan256 - General
aduy Wrote: ------------------------------------------------------- > I'm making a mini portable 3D printer and it's using these cheap 28byj-48 motors. Do you have a thread for your mini portable 3D printer using those 28BYJ-48 motors? I'm trying to think about a mechanical way of tensioning the belt/cable to eliminate the backlash.by Yvan256 - General
AreJay Wrote: ------------------------------------------------------- > I'm making a series of images detailing the > conversion process. > > RJ Is there a new thread for that?by Yvan256 - Stepper Motors, Servo Motors, DC Motors
Given that a single die is only a few dozen to a few hundreds dollars, I guess investing in parts to build a laser cutter powerful enough for the task doesn't make sense. I'm curious about what a "Bluray laser diode hack" cutter would be able to do, however.by Yvan256 - Laser Cutter Working Group
This is why I hate external hosting services like Photobucket. Images disappear.by Yvan256 - Reprappers
NewPerfection Wrote: ------------------------------------------------------- > Those are unipolar, so won't work with standard RepRap drivers. See Sublime's reply about six wires. Also, they're listed at 6.99$USD each, no idea what the shipping cost is for the USA but it's 24.25$USD for USPS Priority Mail International. However, the seller also says "I will try to combine shipping where pby Yvan256 - Controllers
Shipping cost is too high for me in Canada, but perhaps it's more reasonable for people in the USA:by Yvan256 - Controllers
Sorry to resurrect an old thread, but I wanted to say thank you for this information. Would you care to share which HP models had 8mm rods in them, and which lengths? Here's some more information in case someone found this page by searching about scavenging rods from scanners and printers: I found a ~9mm rod inside an Epson inket printer (can't remember which model, plastic went to recycling, bby Yvan256 - General Mendel Topics
Not sure if this has already been posted, but IMHO this is crazy fast: A Better DIY Stepper Motor Driverby Yvan256 - Controllers
I'm not sure if this is the right forum to post this, move it to a more appropriate one if needed. I can't seem to find a "good deals" forums. currently has this motor in stock in all four physical locations, however it's not in their website inventory: Japan Servo Co. Ltd. KP4M2-008 1.8 deg/step 5 wires (unipolar) I can't seem to find a datasheet for these, but they're only 4$CAD. I asked aby Yvan256 - Stepper Motors, Servo Motors, DC Motors
Hello all, I was playing with a printed ball bearing, a sample from Stratasys from a few years ago if I remember correctly,and I had an idea about the fact that printing very small, perfect spheres enclosed in two rings was not the ideal type of bearing for FDM. Has anyone ever tried to print a ball bearing and a cylinder bearing to compare the two? Printing both types on the same printer wouldby Yvan256 - General
I've read about aluminium, copper and brass. Is copper also better than brass? If the heat could be transferred as well as copper/brass, wouldn't an aluminium hot end be better for faster printing since it's nearly three times lighter? (according to the J-Heads wiki)by Yvan256 - Tantillus
It seems someone is already using those RJMP-01-08. Can't wait to receive the samples. I've also asked a quote for 50, 100 and 200 units, I'll forward you the information via PM once I get it.by Yvan256 - Tantillus
> linear bearings don't like having their shafts rotated at all. I didn't know that, sorry!by Yvan256 - Tantillus
Yet another question... I see in the building details that there is "plastic bushings". Can they be replaced by 24mm LM8UU's? Some vendors on eBay already have kits of 12 bearings, I asked one if they could sell kits of 10 x LM8UU + 2 x LM8SUU. Prices for these have really dropped lately! Or would it be possible, if replacing the plastic bushing by LM8UU's, to use a single (centered) LM8UU in thby Yvan256 - Tantillus
The "ultimate goal" of RepRap is to replicate as much of the 3d printer with the 3d printer itself. In that spirit, the Tantillus is better than a Prusa since it requires less "vitamins". Another benefit of the design in the Tantillus is that the side panels can be printed on a 3D printer or cut from wood/acrylic/etc sheets on a CNC router. On the other hand, the advantage of the Prusa is thatby Yvan256 - Tantillus
Could the hot end be made from a bloc of aluminium instead of copper?by Yvan256 - Tantillus
I've checked your building instructions again, and I have a few more questions if you don't mind. Long time reader, first time poster as they say... I was able to get two step motors for 5$ each: Sanyo Denki 103H5208-0841 and 103H5208-0841 (both listed as 2 ohms, 1.8 degree). They already have what seems to be 2mm pulley on them (the short belts that came with the whole assembly have S2M100 andby Yvan256 - Tantillus
I know it's a bit late in the process with all your design already done and all, but IMHO it would be simpler to get the parts if more parts were similar. I noticed that you require two different kinds of LM8UU linear bearings (LM8UU and LM8SUU), most vendors on eBay/etc sell them in packs of 8 or 10 LM8UU. Can the LM8SUU be replaced by LM8UU?by Yvan256 - Tantillus
Never mind those motors... The good news: they're listed at 8.95$USD each, they're NEMA 17 and have a 0.9° step. The bad news: the datasheet says they're 10.78 oz-in while the RepRap motor page mentions a minimum of 19.4 oz-in for a Mendel.by Yvan256 - Controllers
Not sure if these are any good, but the price seems right so the information might be useful to some. They're unipolar but they do have six wires, so AFAIK they could also be used in bipolar mode.by Yvan256 - Controllers