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Re: Avoid first person voice on the wiki? - 14 years ago

I can see both sides here, people do not like to interfere with someone else's stuff, yet we are asked to fill in the author field, I think a wiki is good for such as wikipedia but not the best thing for what we are up to, but then again I do not know what the best thing is, maybe the best thing does not yet exist.

by johnrpm - Administration, Announcements, Policy

Re: DIY printhead - 14 years ago

I will get vesion3 done as soon as possible, if it works I will send you one, the only fly in the ointment may be the extra resistance from the needle, I can cut them shorter but we will see. Edit, Their are two types of syringe body adapter, one type just has a taper and the other has the same taper but with a thread to ensure a tight fit, on close inspection it appears there is a ga

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

I saw it on wiki, it's ok I guess. I think we are at the early stages with this, and don't want to spend lots of time documenting stuff that I do not consider good enough, I have started vesion 3, I have cut the end from a 10ml syringe, (plastipak), it has the taper also a quarter turn thread to accept needles, I like the thought of being able to change the nozzle quickly, I can not find a suitab

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

I am sorry if I have not explained it well enough, I am glad to see someone get involved I will add some more to the wiki when I get time. like the fool I am, I tried to make the nozzle even smaller but ruined it in the process, so am looking at using hypodermic needles, the sort that screw in, and cutting the end from the syringe tube and fixing it to the body, this would allow quick change nozz

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

Hello Casainho, Version one is as simple as it gets, a piece of alluminium machined to take the size of bimorph you are using, with a pocket to take the fluid, I did not do any maths, just by instinct, maybe the volume of fluid plays a part and I was lucky, but if you keep it to a minimum it may be better, the tricky bit is the small hole, by placing a ball bearing ove

by johnrpm - Powder Printing and Selective Laser Sintering

Re: 4 axis TB6560 driver board - 14 years ago

I used one of these boards on a cnc conversion and it works a dream, I am using mach3 so no pport issues.

by johnrpm - Controllers

Re: DIY printhead - 14 years ago

I have started on the wiki page, scratch built piezo print head and added it to the development list, its a work in progress and has already taken more time than the actual experiments, I will re-do the experiments and take images this time, I also added my mistmaker observations as it is also a piezo unit.

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

Assuming it all works , ( hopefully the result of community effort) it should be possible to print wax if the head is heated and fed with molten wax, but that is some way down the line, I literally only spent about a week on this at least 2 years ago, so can not tell it as a finished story, I had forgotten about it until I found the bag of bits, I have followed reprap for a long time and know how

by johnrpm - Powder Printing and Selective Laser Sintering

Re: WHY THE HELL... - 14 years ago

looks like screwed rod to me, some call it studding. edit, sorry, do you mean the double S shaped things under the bed

by johnrpm - General

Re: DIY printhead - 14 years ago

When I sort out the camera situation I would be happy to add stuff to the wiki if you think it worthwhile, The origonal concept was to form a cup shape to 2 bimorphs and solder them back to back to get more force, but bending them cracks the crystaline material, but with a small press tool restricted to the brass surround it should work, I used a standard transformer for the step up and it seem

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

Sorry the images are so bad, my camera gave up the ghost and I had to lash up an old webcam, version one at the top still works well, it was just glued together, the syringe body gives a head to stop the fluid oscilating, the nozzle was drilled about .5mm and closed with a small ball bearing hit with a hammer but I do not know the hole size at present, maybe around .1mm to .2mm ?. The lower one

by johnrpm - Powder Printing and Selective Laser Sintering

Re: DIY printhead - 14 years ago

I did not get as far as measuring resolution, just getting the concept to work, the resolution would depend on the nozzle size mainly I suppose, as well as frequency and amplitude, I intend to revisit this project when time permits, as I believe that the binder is critical to the final strength of parts, and standard printheads limit the materials they can pass through. I will charge my camera a

by johnrpm - Powder Printing and Selective Laser Sintering

DIY printhead - 14 years ago

2 or 3 years ago I played around with making a peizo print head, whilst rummaging through some draws I came across a bag with the bits inside and thought it might be worth sharing, someone may be interested?. I searched for peizo materials and found them to be to expensive for diy, so looked for an alternative and found bimorphes at about 50p each, (buzzers), on a visit to my local poundland I pu

by johnrpm - Powder Printing and Selective Laser Sintering