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Re: Looking for commodity epoxies or ceramics - 14 years ago

@Victor, Thanks! In google age keywords are power

by Igor Lobanov - Polymer Working Group

Re: Looking for commodity epoxies or ceramics - 14 years ago

@nophead, Well, silicon carbide is very hard and has low thermal conductivity. It would be ultimate material for laser sintering, but it's not printable. And it is suspected to be human carcinogen. However, I'd be glad to find good thermal insulation ceramic regardless of whether it is strong in elongation or not.

by Igor Lobanov - Polymer Working Group

Looking for commodity epoxies or ceramics - 14 years ago

Dear All, I'm thinking about printing various currently non-printable working parts for RepRap such as hot ends, mixers, etc. The printing process in itself is straightforward, syringe-based extruder and proper calibration can deliver high-quality prints. The only problem is to find more or less common substances like ceramics or epoxies that once cured obtain required properties. In particular

by Igor Lobanov - Polymer Working Group

Re: Auto Calibrating Extruder - 14 years ago

@VDX, Fascinating, thanks! And DIY-friendly as well. Perhaps must have for home-made SLS machine

by Igor Lobanov - Developers

Re: Auto Calibrating Extruder - 14 years ago

@VDX, Great idea! Optical sensors are very cheap and one could easily print reliable encoder wheel on any desktop printer. 8 tracks is enough to ensure 1.5 degrees angular resolution. If there are, say, 10 full revolutions of the encoder wheel per 200mm area, you get 78 um resolution.

by Igor Lobanov - Developers

Re: Auto Calibrating Extruder - 14 years ago

@Lanthan, Sure, I believe 30-50 um resolution is attainable in practice. The thing is to find a commodity conductive material, that could be used for the strip. It can't be just copper wire -- resistance is to low. Any ideas? BTW, if printing carriage was driven by printed herringbone belt, the belt itself would be an ideal place for mounting the conductive strip.

by Igor Lobanov - Developers

Re: Auto Calibrating Extruder - 14 years ago

@Lanthan, That's true, but you can easily get standalone 4-input 16bit ADC for $5.

by Igor Lobanov - Developers

Re: Printable ceramic hot end - 14 years ago

@Buback, I've found very interesting ceramic materials online, including those with very high working temperature ranges. For example, on cotronics.com. However, it doesn't look like there's a way to buy those in retail amounts, not in the UK anyway. Haven't spoken with them yet, though. Will try at some point once my reprap is operational and I manage to build a claystruder. @nophead, That's

by Igor Lobanov - Developers

Re: Auto Calibrating Extruder - 14 years ago

As far as axes are concerned, a possible alternative to magnetic sensor would be a strip of conductive material, sliding contact head and simple current or resistance sensor. Under the voltage position reading of the sensor will be linearly dependent on the position of the head. It would be effectively a large variable resistor.

by Igor Lobanov - Developers

Re: Printable ceramic hot end - 14 years ago

@Buback That's interesting. What sort of plaster you're going to use? Gypsum?

by Igor Lobanov - Developers

Re: Printable ceramic hot end - 14 years ago

@nophead There may be no de jure standard build, but de facto standard Prusa build is definitely as it described on the wiki. Similar thing is for electronics and extruders with a bit of variety. I know it as I'd spent ages shopping around for printed parts and electronics kit. Whenever someone offering you a set of printed parts for Prusa, you can expect it to be the same as described. On the

by Igor Lobanov - Developers

Re: Printable ceramic hot end - 14 years ago

Well, that's understandable, designing parts is tough On the other hand, while it's still not clear for me how novel part designs gets incorporated into the 'standard' build, apparently lots of people do hack around printer parts and make substantial improvements.

by Igor Lobanov - Developers

Printable ceramic hot end - 14 years ago

Dear All, I've only just started building my own first Prusa, so my observations might be incorrect, but it seems that the most "vitamin-hungry" part of the RepRap as it is now is the extruder and hot end in particular. On the other hand, apparently, lots of progress has been made by the community in the area of clay/paste extruding. Those devices are perfectly capable of working with ceramics a

by Igor Lobanov - Developers