Possible to convert Rapman 3.1 to reprap extruder?

I posted a few days ago about my Rapman 3.1 having issues with feeding and the pressure bearings, and I did some research and saw that now reprap has moved beyond the screw-drive extruder. Would it be possible to change the extruder on my Rapman to a different style extruder that is more reliable? Would I have to get a new board, or would I be able to use my existing electronics?

Edited 1 time(s). Last edit at 06/07/2013 02:42PM by npolanosky.

I am just looking at doing the same thing!

To extend the life of your Rapman extruder, disassemble the extruder and throughly clean it. In particular, clean the plastic out of the threads on the screw drive. Also, I found that the PEEK insert in the hotend had deformed, causing higher friction on the filament. Reassembly and check for tightness and alignment.

A combination of these problems led me to doing the same thing you, increasing the pressure on the rollers until the screw strips the filament.

I have now replaced my hotend with one off ebay, and I am printing about as well as I did before.

I am modelling the X carriage assembly in OpenSCAD, and designing a tool mount for a standard Greg/Wade type extruder. I will also try to create a mount for a Reprap J-head or other type hotend.

However, I have already replaced the BFB electronics with a more Reprap friendly board. If using the BFB electronics and you did a straight swap of Rapman extruder to Reprap extruder, you would have the problem of setting the steps/mm for the extruder. That is built into the BFB firmware and I think closed source.

You might be able to buy some replacement parts from BFB, if they are still available, but I prefer the open source route that is more viable long term.

What electronics are you using, in that case? I'd prefer the open source stuff as well.

I am currently using Gen7-ARM, previously was using R2C2, also my own design Sango-bc. However pretty much any Reprap electronics/firmware will work, it is mostly a question of wiring. The BFB hotend uses a 200K thermistor, so some changes to firmware is required for the thermistor table. There may also be some tweaks needed for the Y endstop, I configure it as a max endstop, also need to make sure homing is done X-Y-Z order without any funny moves in between.

Apart from that, it looks like a fairly standard Reprap.

Also there is little support now for the Gcode produced by Axon, I now use Kisslicer with the "5D" style, and I use pronterface to control the printer.

I got the extruder working finally, trying to get the settings dialed in to print reliably without warping and such. still interested in a different extruder setup, but WOW, it seems like all these boards are expensive.

How much would you expect to pay?

I think there is almost a board to suit every budget, if you are willing to do a little DIY. Generally the more you pay the more features/better quality.

Overall though, the cost is largely determined by volume, and most boards are made on small productions runs.

I might go the DIY route, or just save some spare cash for a bit. Basically I got the printer for free from my high school, and I can keep it provided a) I can get it working. and b) I can convince some company to at least partially fund buying a newer, better supported, and more reliable printer for the school.

I wouldn't mind the price, but this is also in addition to my other primary expensive hobby; large-scale RC airplanes and long range FPV flying and aerial photography. I'm not scared of a soldering iron or an arduino, in fact I love both of them