Having just been through this NIGHTMARE, I can guess what is wrong with it... Assuming your board came from ebay as part of the £147 i3 kit, and was preconfigured with max and min end stops in the firmware and only min end stops in the kit... 1. there is no bootloader on the mega so you cannot upload new code via usb 2. you need a usbasp (or use another arduino as ISP) to fix the bootloader 3.by JohnW - Prusa i3 and variants
Yes is the answer to the question :-)by JohnW - Sanguino(lolu)
Just a quicky before I launch into a major debug - are the end stops normally open or normally closed? I bought an assembled and tested Sanguinololu from eBay it powers up and connects fine with pronterface but I get naff all out of the stepper motors when I try and jog :-z I know the steppers are wired up correctly and the 12v power supply is fine, but I dont get a step, buzz or even a hum. Tby JohnW - Sanguino(lolu)
Ex-shipping a P3 sized 3mm clear acrylic with a 200 x 5mm holes and bracket outlines is like $44 seems really reasonable.by JohnW - General
P3 is 790x384 P1 is 181x181 Acrylic seems to be limited to 3mm but thats all I had a chance to look at so far...by JohnW - General
To the UK now a P3 sheet in 3mm Acrylic would be like £15 rather than £45 - now this might get some more laser cut machines going surely? Might get some time to look at this soon....by JohnW - General
If the number of bearings required is the only oversight then we're in luckby JohnW - Mechanics
Hmm, interesting. Was exercising using a 2.3 stepper driver - set the current limit to 0.5A, going clockwise it was fine. Changed it to anti-clockwise and after about 3-4seconds it blew the board. I thought the funny smell was the soldering iron Never mind.by JohnW - Mechanics
And if you went up a bit in chip you could probably run all three axis on one MCU.by JohnW - Mechanics
Well a mega8 and 8 FETs or an Hbridge could be had for < £3 and be easier to proto and deal with much more current and voltage? Quite a few projects on AVR freaks ready to go so no coding required either.by JohnW - Mechanics
Blimey the chip is nearly £7 from Farnell and Digikey I got some v2.3 boards and some 3982 chips a while ago that I haven't built up yet but I recall that driver being around £3.50. I did try one with solder paste and it never worked proper - so i'll hand solder it in a bit and take it to work tomorrow to test!by JohnW - Mechanics
These look like a cost effective alternative to the V2.3 electronics since you cant seem to get them assembled in the UK?by JohnW - Mechanics
Most of the steppers we use in our machines are high speed 24v efforts - but at 0.5ohms I seriously doubt its going to be 24v as that would be 48amps right? Hopefully I can get the drawing tomorrow.by JohnW - Mechanics
So this stepper drives a controlled pressure nip which I believe is why it has an encoder, its off a large inkjet rather than xerographic machine. The resistance between the coils is 0.4-0.5 ohms - my meter isn't precise enough. I have asked the guys responsible for that area of the copier to send me the drawing and specs for it so I know what it really needs. I have 5 of these now, so shouldby JohnW - Mechanics
Been struggling to get started really - did find some new stepper motors today in the car park on some salvage copiers. Should be good for the CNC milling machine I am planning on to produce the parts for a reprap. Plan is a Sieg X1 home CNC'd to make the parts for the reprap. These motors are pretty beefy - havent had a chance to lookup any data on it but did notice they have encoders built oby JohnW - Mechanics
Hi, Really interested in this - your site seems rather devoid of notes but I tried uploading the latest version of rsteppercontroller. It verifies ok but when I try to upload it fails Binary sketch size: 10498 bytes (of a 14336 byte maximum) avrdude: stk500_getsync(): not in sync: resp=0x00 avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51 Bascially all I want is a g-code intby JohnW - RepRap Host
Do an export to a DAE file from sketchup, open it in Blender, export it to STL.by JohnW - Reprappers
Well I ordered some boards from makerbot - came to < $20 for 5 boards inc delivery - which I believe is under the customs radar after poking around. Lets see how it goes, they dont have the mobo on their site yet. John.by JohnW - Controllers
Hi People, Long term lurker, started pulling together some of the bits needed to build me a rep-strap - which will then hopefully be able to make a reprap! I really like the looks of the Gen 3 electronics and was wondering what the best option to get 3x stepper control boards and 1x mobo was? I feel confident in making the boards but I can only make single sided easily and rather than re-drawby JohnW - Controllers