Sebastien: I mostly cast fake claws and animal-style paw pads for people doing costuming, LARPing and so on. (Trying to widen my range ASAP. Over-specialising is not helping!) I've also used it to make some Mendel frame parts, and make duplicates of some useful pullys and gears. I use RTV tin-cure silicone moulds, though trying to learn other types that may be of use. The epoxy-granite is indeedby Sci - General New Machines Topics
Also, created wiki page as requested. Will improve as time allows. Now to bed.by Sci - General New Machines Topics
Snagged a brief video of the folding mechanism in action. May create issue with running bourdon cable, but something will come to me. Also, logging day to day progress on my creative blog. Can be followed specifically by following entries under the "reprap" tag.by Sci - General New Machines Topics
As is wont to happen with my projects, I've been working on this without maintaining a visible record. I have at least been taking photos and will attempt to get a retrospective of work so far up soon. So far though, some of the changes have been thus: Simplifying construction by using the frame studding as the runners by sheathing them in stainless-steel tube. This has the added benefit for raby Sci - General New Machines Topics
I spotted a batch of surplus stepper motors going cheap. 2000 stepper motors. It immediately occurred to me that this is perfect for a small production run of something. A few sums and tests later, and I bought them. The motors are several times weaker than the ones used in Mendel, but I think I can produce a small repstrap machine based on the Mendel design. It'll be stripped down to the bonesby Sci - General New Machines Topics
I've been lucky enough to find someone nearby throwing out a large Fellowes 120C-2 shredder. It apparently ingested one of it's own clearing combs after a toothed cutter came loose, melted the comb from friction, blew two more wheels and finally popped the side of the assembly with enough force to shear a bolt. After disassembling and cleaning, the 1/4hp motor still works, no gears are stripped aby Sci - General
Could just put gaiters around the moving parts to keep spatter off them? Additionally since this would be a positive-pressure setup, all we're talking is putting the machine in a non-flammable box. Though with heat buildup, would probably want a fan in there to circulate the gas. Possibly even a heat exchanger.by Sci - Plastic Extruder Working Group
Lionel - Thankyou, taking it there. Alex - Hiya Alex! Wouldn't it be easier to just import the STL files to autodesk, rather than try and make new 3D models from 2D drawings that would be created from the STL models anyway?by Sci - United Kingdom RepRap User Group
This would seem relevant to this idea. The Clock of the Long Now. It's a project to design and build a clock that will keep accurate time for the next 10,000 years. Their current design uses a fully mechanical binary computer to avoid the accuracy problems associated with analogue states. Complete CAD files were available, though I can't see them readily on the site now. I have a copy saved to myby Sci - Plastic Extruder Working Group
I can't readily see a thread for such recycling. Have I missed it? Would probably be a good point to branch into a separate one if not. Yesterday I was lucky enough to find someone nearby throwing out a large Fellowes 120C-2 shredder. It's apparently ingested one of it's own clearing combs and jammed, but the teeth look good. If being jammed hasn't burnt out the motor (1/4hp) or stripped any geaby Sci - United Kingdom RepRap User Group
Well most bits could be produced with a coping saw and lot of time and care. 3D objects aren't too easy though. What if the parts were reformatted into arrangements of flat sheets? Cut out from, say, 12mm MDF, then glue the layers together to make the 3D part. Just print the 2D plans, glue them to the board and cut around. Relatively easy if someone can modify the design files. So far I've got tby Sci - Casting and Moldmaking Working Group
This idea only just hit me, regarding the issue of printing in metals. It seems similar to the existing extruder in that it could operate from a spool of material. With MIG welders fairly common, a test setup would not seem hard to produce. It would need some modification of wire-feed controls however. Further, it got me wondering if it could be fed with multi-strand wire of different materialsby Sci - Plastic Extruder Working Group
For printing metals, induction heating may be a possibility. I've considered it myself. There are some issues though. Requirements for a large transformer and fairly complex control electronics unless you're going to use water-cooled HF valves and huge resonant coils. (the 4Kw one I had the pleasure of using was 7ft tall, ran off a 3-phase line and made a loud bang when the water loop breeched onby Sci - Plastic Extruder Working Group
I'm just curious if anyone's measured how much lateral force is required to dislodge a printed item from the print bed? I'm sure it's different for different materials, but I'm wondering if it's within the power of the Y-axis if a fence were added on the extruder. IE: On completion, move Y-axis to one side, lower head, move Y back across to knock object off with the extruder (and presumably off tby Sci - General
Well Dave Gingery passed on a few years back, but his books are still being sold, so I doubt they'll go public domain any sooner than the law specifies. It'd probably be easier to do a new guide from scratch, or just buy the collection. Something like figurines is what I'm getting back from people, so being able to paint or colour them seems a must.by Sci - United Kingdom RepRap User Group
Presuming that's dual-purposing it for vacuum seals for gaining access to the chamber too? I've not used oil seals before. Most of my experience has been in rubber (viton) or copper gaskets. Also RTV silicone for my home made degasser. Hatch-style, a knife-edge seal could work fairly well, though would need a good pumping speed to suck the surfaces together. I can see a viscous oil would certainlby Sci - Controllers
Using NASA's metal-depositing 3D printer as an example, printing metals in a vacuum removes the problem of metals oxidising when deposited. But if you have a vacuum environment on hand already, it's also good for thermionic valves. The idea of printing huge glass bulbs is right out of course, but valves didn't die off right away with the advent of the transistor. They fought to survive and gotby Sci - Controllers
That's rather a good idea! Automotive filler might be a good choice to use.by Sci - Casting and Moldmaking Working Group
The series certainly has a sort of similarity to RepRap. The instructions take you from making a charcoal foundry from scrap, through casting aluminium, and using it to build yourself a machine shop. Each stage building the next. Got an old upright compressor tank that'll make a nice foundry at some point. > I know a few artists, but most are fairly traditional. It's a good idea though, we juby Sci - United Kingdom RepRap User Group
I'm looking at making wooden versions of the parts too, but for making moulds to then cast plastic ones. You may find the shareware software Pepakura Designer 3 helpful. It's made to take 3D files (including STL) and output a layout you can cut and fold to produce a replica. Just untick "2D Menu > Show Tabs" and go to "Change Scale > Scale Factor.." and make sure the scale's set to 1.0000.by Sci - General Mendel Topics
Last 24 hours I've been going over the files. Found I can print them out perfectly scaled using Pepakura Designer of all things (well, except "x-vert-drive-side-plate-360-end_2off" because the rear face splits up too much, and I can't join the seams). Since the Mendel design appears to be over-engineered in places to account for possible printing flaws, and the positioning of the parts can be vaby Sci - Casting and Moldmaking Working Group
From my POV; mostly the rough surfaces the printed parts have as well as the undercuts. The silicone will seep through any gaps in the printed parts, so you could end up with a part fused to the mould. Rough surfaces also wear the moulds out a lot faster as they provide more points the silicone can rip or split from. Plus for multi-part moulds, a rough surface would make it much harder to mate paby Sci - Casting and Moldmaking Working Group
Hi Lionel, I wouldn't be surprised if the lack of UK membership is because of the country's shift away from manufacturing industries. Many of those with a real enthusiasm for engineering seem to end up being employed overseas, or worked into the ground, giving no free time. Maybe we just need to raise the profile of it in the UK though? I'm trying to find someone with a hobby mill who'd be willinby Sci - United Kingdom RepRap User Group
My names Peter, though most call me Sci. 29, self employed and living in London, E4. A reprap would certainly help my very small scale prototyping and development needs. And since so many people seem to have trouble getting the printed parts, I'm trying to see if it's feasible for me to make and sell cast versions. Plus I have a large vacuum chamber I aim to get working (18" dia. ex surface-coatby Sci - United Kingdom RepRap User Group
I'm new here, but I've been using RTV silicone and polyurethane fast-cast resins for a couple of years now. I'm in London, England, and can think of a few ways of going about making the parts from moulds. Multi-part moulds would solve some of the issues. I've made odd-shaped silicone "plugs" to place into setting PU that eliminate my need to precisely drill them out once set. As far as the threaby Sci - Casting and Moldmaking Working Group