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Here's what I made, here's a photo, and here's a link to the [[page]] on RepRaps wiki!
Robot Grippers - 12 years ago
I spotted this online and thought it might be of interest as its made from a balloon and coffee grounds. Robot Gripper Does anyone know where I can buy vacuum cups for a robot online? I live in the UK, so would prefer Uk or Europe online shop if possible.by martinprice2004 - Robots!
Re: Please suggest how to improve this print: - 12 years ago
The round overhang can be caused by the following. 1) if its on the first layer it may be bed adhesion. Are you printing the first layer too far away from the bed? It needs to squeeze slightly on the bed otherwise the perimeter pulls away. 2) You might need to put up the extrusion a little bit on the perimeter printing . It looks like its not extruding enough and this stretches the filament acby martinprice2004 - Printing
Re: Helium Frog HF06 "SCARA" Robot - 12 years ago
@NoobMan Yes the best place for the motor would be further back towards the frame above the first pivot as this would reduce the arm inertia. Unfortunately I couldn't do this as the motor would then clash with the top of the Z axis frame. I could move the whole assembly outward a little, but this has its own problems as it increases the cantilever loads on the linear bearings. I have seen SCARAby martinprice2004 - Robots!
Re: Wade extruder jamming - filament feed rate or hot-end temp to blame? - 12 years ago
When the printer jams up, in Pronterface hit the pause button, then in the send box (bottom right) type M105 then hit the send button. This reports back the temperature of the hot end and heated bed. If the temperature has dropped off, this may be the hot end over temperature protection switching off the hot end. Switch on smoothing in the firmware. I dont use 1.75mm filament myself , but I assby martinprice2004 - Mechanics
Re: first layer problems - 12 years ago
Are you using any tape on your heated bed such as kapton?by martinprice2004 - General Mendel Topics
Re: Extruder heater shutting down during build - 12 years ago
It depends on your firmware, but check to see if you have thermistor temperature smoothing set on. I was getting interference from my thermistor readings and occasionally getting a spike temperature which switched off the hot end. Switching on smoothing stopped this as it averages out the thermistor readings so they can only rise and fall slowly. The MAXTEMP setting is to stop the hot end damagiby martinprice2004 - Reprappers
Re: CNC MILLING AND 3D PRINTER IN ONE - 12 years ago
The motors in the link are designed for retro fitting a miling machine for CNC so should be suitable for what you want to use them for. Don't use standard threaded bar, it is awful and bends. This introduces wobble in the carriage and results in rough parts. At the very least buy proper lead screws (acme etc.). Its not common to use belts for a milling machine as they don't respond too well toby martinprice2004 - General New Machines Topics
Re: Sprinter M190 (set bed temp and wait) not working - 12 years ago
Nice bit of coding M116 would be a useful addition. On my machine because I have a high resistance bed it takes a time to heat up, so I don't really want my hot end waiting at working temperature for a long time whilst its not extruding as this may cause excessive heat build up in the insulator. It would be nice to avoid this, say wait until bed is 5 degrees below target then switch on the hot eby martinprice2004 - Firmware - mainstream and related support
Re: Parametric pulley - lots of tooth profiles - 12 years ago
GT2 timing belts are nice, but here in the UK they are not readily available as far as I can tell. You would have to phone up industrial suppliers to get them. I like T5 as you can get them easily by shopping online and can have looped belts of any length made up. There are many suppliers. All the T series belts seem easier to get here. Are they readily available in other countries?by martinprice2004 - Developers
Re: Helium Frog HF06 "SCARA" Robot - 12 years ago
Just thought I would post an image of the SCARA build so far. Most of the parts are printed and the main frame assembled. More details at Helium Frog websiteby martinprice2004 - Robots!
Re: Helium Frog Delta Robot - 12 years ago
The Helium Frog Delta Robot is sort of still in development! I have nearly completed another design which uses vertical belts and has a few other improvements. The threaded rods were the worst idea on the delta, and belts would be much better. I have also been working on another design, which uses two linear rails mounted horizontally with two arms in a triangular configuration for X and Y axisby martinprice2004 - Delta Machines
Re: Tracking down one last issue, ooze? - 12 years ago
From the look of the lower ring it looks like you are extruding too much material as the layer is overfilled. This would cause probelms on the pillars as if you are doing the same for the perimeter the material would ooze off the sides.by martinprice2004 - Printing
Re: Parametric pulley - lots of tooth profiles - 12 years ago
As far as I was aware, timing gears are not cut in industry as that would be too expensive. There are two main methods of manufacture. 1) Sintering. Pressed from a powder and then "fired" in a kiln. Its cheap for large volumes, but a very restrictive process. Its difficult to produce flanges at the ends due to variations in powder density, so is generally limited to one flange or no flange desigby martinprice2004 - Developers
Re: Pick and Place toolhead, STL files included! - 12 years ago
Sparkfun do a vac pump which might be of use rather than using an aquarium pump in reverse. Vacuum Pump As for webcams. Probably the best home use camera on the market at the moment is the Logitech QC9000. It has a hires sensor (True 1600x1200 not interpolated) and also has manual settings which is vital, which many cameras do not have. I have also stripped and fitted a "C" Type lens to one.by martinprice2004 - Pick-and-Place Electronic Assembly (and robots!)
Re: Parametric pulley - lots of tooth profiles - 12 years ago
I print using a 0.5mm nozzle at 0.5mm layer height, so my gear form is not the best, but the image I posted seems to work OK and I cannot feel any backlash by hand so far. I haven't run my SCARA robot yet, so I cannot say for sure whether they will be OK when running around an 8 tooth motor drive but I am more confident the 40 tooth pulley should be OK. At least if I can print the large pulley aby martinprice2004 - Developers
Re: Parametric pulley - lots of tooth profiles - 12 years ago
nophead said "How does more teeth help? They all have the same profile, so if the profile gives backlash the only benefit of more teeth is more friction resisting it." Unfortunately in the real world when producing any part there is a natural variation. These most often form a normal distribution around the mean value. This means that the teeth will vary in thickness around the pulley. Having tby martinprice2004 - Developers
Re: Parametric pulley - lots of tooth profiles - 12 years ago
The parametric models you have produced will help many people I am sure. I have been doing a few experiments with printing timing pulleys and I have found that simply trying to duplicate a standard metal pulley in ABS doesn't seem to work that well. I think it is probably due to the variation you get across the tooth pitch when printing on a reprap and also the slight rounding you get at the corby martinprice2004 - Developers
Re: general licence questions and vendors as well as eBay - 12 years ago
I believe there were two questions that terramir asked as follows and are directly addressed in the GPL licence:- "Now are people selling the stuff violating licenses here and what are the implications?" "do I have to get permission from every single one of the contributors first? like traumflug (gen7) electronics and let's say wade (extruder) adrian (general DESIGN) prusa for his updates andby martinprice2004 - General
Re: general licence questions and vendors as well as eBay - 12 years ago
Actually the Reprap and all derived works are under the GNU licence, so your understanding is not correct. Reprap GNU General Public Licence This a much more open licence, but the essentials are as follows:- You can copy, sell, redistribute the designs, modify the design and sell that. In fact its actively encouraged. You cannot take the design, modify it and then sell it as a closed sourceby martinprice2004 - General
Re: Belt driven vs gear driven Wade's Extruder - 12 years ago
I seem to recall that there has been a design for this, perhaps on thingiverse. I think this would be a good idea, not only for backlash, but it also means the pitch between hobbed bolt and motor is not controlled by the gear ratio. This restriction limits the design of the extruder main body. You can see this has been a problem in Gregs hinged extruder where the gear ratio has had to be alteredby martinprice2004 - Mechanics
Re: Hot end temp problems - 12 years ago
I have had this exact same problem. I checked out the thermistor and mounting and found it all OK. It must be interference in the leads or electronics somewhere. Moving your machine, rerouting wires, changing power supplies and leads can cause this problem which is I think what caused my issues. I was getting the reading fluctuate high so the hot end switching off mid print ruining parts as it sby martinprice2004 - Reprappers
Re: Some help for a beginner - 12 years ago
When buying electronics / motors, try buying them together as you can get discount kits which include everything. This way you can save a lot of money / postage costs.by martinprice2004 - General
Re: 2DOF Servo Arm + Stepper X-axis - 12 years ago
I am just developing a SCARA robot here which may add a little to the debate. I am just printing off the first parts at the moment. I hope to get it working in a couple of months. The accuracy and resolution of these robots will be less than a cartesian robot, but with careful design it should be good enough for FDM. It is possible that this type of robot could be the first to self replicate.by martinprice2004 - Developers
Re: Scaling Mendel - 12 years ago
Just a few more thoughts. A wing section would probably mean that it would need a lot of support material if made horizontally as both sides are usually curved. Perhaps a wing would be better made vertically. Less warpage and perhaps it could be supported at intervals. A central carbon fibre tube could be glued into the finished part down through a vertical hole. The fuselage could be made in aby martinprice2004 - General
Re: Scaling Mendel - 12 years ago
A long thin machine would be much easier to engineer, say 200 x 1000. You could use linear rails for the long axis with open bearings. This way you could support the axis mid way. Theres an interesting article on rapid prototyping model aircraft that might be of interest. I have already suggested to them on their forum that the reprap project might be of interest to keep the "Men in Sheds" approby martinprice2004 - General
Re: Copyright - 12 years ago
These are not personal attacks. I think the machine is very well designed and would be very popular, but stating that it is patented is a little misleading. There is a good example of a company that has made a lot of money with an open source design, that of Makerbot. They didn't go down the patent route, but setup to quickly churn out their design in large quantities at a reasonable price. Theyby martinprice2004 - General
Re: Copyright - 12 years ago
Yes a patent is required for a machine. Theres a neat expaination here. In addition the patent needs to detail the exact nature of what is unique and under protection. Its impossible for anyone to patent this machine as there are many components on it that are not original, such as the hot end, extruder, heated bed, guard system, table axis design, rack and pinion mechanism. If there were a uniby martinprice2004 - General
Re: Are 6-Wire Nema stepper motors compatible for use with Repraps ? (Here-we-go-again, lol) - 12 years ago
The Reprap wiki should give you a clue. stepper motor They are unipolar motors with a centre tap, giving 6 wires. You ignore the centre tap wires and just use four. This is what I found in google images by typing in the serial number... a wiring diagram the same as you have, but you sometimes get lucky with a proper datasheet. wiring. It looks like you ignore yellow and white wires.by martinprice2004 - United Kingdom RepRap User Group
Re: UK Where to buy PTFE cable? - 12 years ago
I find Farnell very good and the delivery time is exceptional. Heres the stuff I use. PTFEby martinprice2004 - Controllers
Re: Full crosbraces for Prusa Mendel - 12 years ago
Yes sounds a workable solution. Perhaps theres a way to set it up so the laser movement is amplified across the scale. The improvements will likely be in the fractions of a millimeter in X so we it needs to be something quite accurate. Accurate measuring devices are getting quite cheap nowadays, so don't be put off getting a bit professional, for example dial test indicators (dti's) start at arby martinprice2004 - General Mendel Topics