I'm really happy to find there's still activity on this forum and have started a build based on laser cut case parts and metalwork from Drakken. I've printed out the corner parts for this, but they seem oddly flimsy. I have test fitted one of the base corners on a couple of acrylic sides, so the dimensions seem fine, but the side walls are formed of two thin walls each, with a gap, as if there sby chrisbob12 - Tantillus
I'll be following this with interest! I've bought a set of laser cut casing parts + various bits from Tony Davies' Drakkn workshop. Just need to get past improving my Prusa with a thermal hood and re-routing the wiring before I print off the necessary parts.by chrisbob12 - Tantillus
I'm getting a glitch in some of my prints, where the layer shifts over by about an extrusion width when there is a change in cross-section. In my case extrusion width is 0.5mm (nozzle diameter). The change in cross section can be a lateral hole finishing, or a simple change in section. It doesn't always happen, but when it does, it looks bad (the rest of the walls built up look fine, so the glitcby chrisbob12 - Printing
@Matticus: what sort of improvement do you want on your existing setup?by chrisbob12 - General
As a follow-up to my last mail: I bought a new batch of black abs filament from 3Dfilaprint, and it's going fine; so I think a lot of my initial problems were filament quality. I have to disassemble some of the Bulldog XL drive to get new filament in, but once it's going, it seems pretty happy. I aim to get some better (i.e. deeper channel) hobbed bolts to see if I can get better performance froby chrisbob12 - General
Thanks for the help everyone! I went through a number of the diagnostics suggested + one more. @A2 - I couldn't push it through by hand, but I struggle to push it through that extruder even when the whole hot end is off, of which more, further down. As it happened it was blocked. I swapped back to the Wade extruder, in which it's easy to push the filament by hand. I couldn't get a reliable runby chrisbob12 - General
Question for Bjorn: I have installed a Bulldog XL from RepRapDiscount onto my Mendel Prusa, with the Merlin hotend. This replaces the previous Wade's extruder, with which I'd got some OK prints. Does the Merlin hot end benefit from the cooling fan supplied with the Bulldog? The reason I ask is that I have been trying to commission the Bulldog and have not yet achieved reliable extrusion. It mby chrisbob12 - General
I fried my Bulldog fan by connecting it the wrong way round (despite reading that it needed to be connected red +ve etc durrr) I looked at the suggested replacements above and they look promising, however, RRD sell the replacement fan unit. The prices for the proposed substitutes are very similar to RRD, and the Mouser shipping cost is very similar to RRDs. I went with the RRD unit, and have itby chrisbob12 - General
PM sent - thanksby chrisbob12 - General Mendel Topics
I've started work to install a Bulldog XL extruder on my fairly vanilla Mendel Prusa. I'm replacing a Wade's extruder. The mounting holes on the carriage line up with the Bulldog plastic base (more or less), but if I position the Bulldog so its fan end is towards the end stop, the fan housing hits the z-axis slide before the carriage hits the end stop (and the extruder doesn't make the full widthby chrisbob12 - General Mendel Topics
I think I've fixed it. I moved the Polulu board to a different axis on the RAMPS board, and the problem followed the board, although in a different way: I moved out to the z axis, and it cut out after a period of working. Eventually decided to inspect the board under magnification, and saw one of the header pins had a dubious-looking joint. I re-soldered the joint, and it looks to working right -by chrisbob12 - General Mendel Topics
I've got a newly built Prusa Mendel with a RAMPS 1.4 board running Marlin firmware being driven from Prontrface. I'm more or less calibrated and have printed a couple of calibration pieces. Hurrah. Just the other day, the extruder stopped printing part way through a print. Bah. I find that when every thing's just fired up from cold, and the hot end has reached temperature (240 deg) I can extrudby chrisbob12 - General Mendel Topics
@james glanville & @NoobMan Thanks for your responses. I appreciate the L298 is pretty old hat, but having forked out for the components (and it wasn't pennies) I'd like to use them. After a bit of further searching, I found these - I'll just graft them onto stripboard, which is my default method - the main obstacle to using stripboard was the staggered pinout of the L298, and this solvby chrisbob12 - Controllers
I'd love to lay my hands on a set of three unpopulated stepper motor boards which take L298 bridge driver chip (in the big multiwatt package). I kitted up a full set of parts for these to make a CNC bed from the Geoff Williams book, but my home etched boards are pretty poor (Geoff's board designs are not all that hot either). I found that the early reprap boards are the same circuit (pretty muchby chrisbob12 - Controllers