Sunday, 25 September 2011

Progress Update 5

Today I really really want this printer to do something other than take up space, And after the other nights efforts of Nuking a few stepper controller chips I have decided to install the old crappy Gen3 electronics set.

Oh the Gen3 is a Ugly ass creation, effective to some degree but its a mess!

In my travels today I latched onto some lubricant, Its a can of Spray lithium grease, it smells a little,but no where near as bad as the marine bearing grease that I had used on the old printers axis'
 and @ $10 a can its a bargain, this will make a thick layer on what ever it is sprayed onto, this will be great if i every have to park up the printer and store it for a bit while not being used this will prevent the steel from going rusty.

here is a picture of the printer as it stands, apart from the extruder the beast is wired up.

While i was attaching the endstops someone on IRC #reprap had asked the question about an easy way to square up the print bed, having seen this question pop up a few times previously i thought about it for a moment and devised a simple Z probe for my printer. this is what i have come up with.

 here you can't really see it through the glue holding the cable into place, but i have a tiny micro switch with a lever that hooks into a bit of brass tube that the bolt pushes up, there is a little slot that the lever fits into, this allows me to adjust the height with out it interfering with the amount of travel.
here you can me pressing the bolt head up to illuminate the indicator LED. now i am not 100% sure if this will work, or if its useful so i have also made a traditional micro switch endstop for the Z axis Min, just in case. I am thinking of putting in a switch that will allow me to choose between the two options. MIN or Z probe. the firmware will be fun.

Things left to do.

Need to go an purchase a piece of glass that is 2mm 470mm square, the framing shop quoted me $25 cut to size.
Will need to weld up the frame that will support the glass, heat spreader, element and heat shield. this will be place onto springs and held down with some screws to provide adjustment to get the bed nice and square to the extruder . ahh that reminds me i think i will get the glass cut with some 20mm 45' cuts on each corner to allow for the adjusting screws, getting the corners cut off is much much cheaper than getting holes drilled into the sheet glass.. not as pretty but who is going for looks, i want functionality.
Then all that is left is the Extruder...

but for now i am going to go and play with some firmware to see if i can get it to listen to the endstops. i was playing with Teacup firmware by Triffid_Hunter. but the version i had doesn't explain the endstops really well, so i have no idea if i am configured correctly.
So now i will try Sprinter by Kliment and see how that goes.

Ok Sprinter seems to be working  great, i managed to map all the pins to my setup and i can exercise all the axis' My X and Y axis' move upto 1700mm/min (283mm/second). this is GREAT its about 27 times faster than my previous printer, but the accuracy has been reduced i get 4 steps/mm (ie 0.25mm steps) i will be getting some new 10T pulleys and some new stepper driver chips that will allow better micro stepping option. this will give me 64 steps/mm :) 0.015625mm/step..  i could go even further and use a 8tooth pulley but the belts do not like going around those. the radius is too tight, and would require an idle roller to over come that, that sounds like too much trouble and will only give me an extra 16 steps/mm not sure if i need that level of accuracy.

so far i have tested all three axis' they all work fine except for Z it seems to bind in the upper 30mm of travel, not too sure where the problem is but i dont care about that. this limits my print area to 470Wx470Lx175H on the small bed. ahh things never work out how you plan.. :)

No comments:

Post a Comment