8-Bit Hack

I love how smooth the movement is with the v-groove bearings and v-rails.  It is really a beautiful thing.  So beautiful in fact that I had to take a video of it.  There is (almost) zero (happy?) slack on the movement, the sound you may hear when I switch directions is the mirror/lens assembly moving a bit since I haven’t tightened it down yet.  I have all the rails and frames drilled, tapped and assembled.  I’m working on the z-axis bearing pieces now and all the acrylic that needs to be drilled/tapped is done.  Assembly is moving forward as fast as the heat permits, it’s been somewhere close to 5000ºF here in Houston lately and I haven’t setup the portable AC in the garage yet.  I should really do that, maybe this weekend.  Just need to cut a hole in the ceiling for the hot air exhaust.  Here’s a video of the progress I’ve made on the laser so far.

So I’ve been slowly collecting hardware for the laser cutter and I think I’m just about done.  I currently have a huge pile of little bags of various fasteners on my workbench.  Nuts, bolts, washers, lock washers, cut washers, t-nuts, bearings, rails, threaded rods, etc.  I have a few more bits and pieces coming over the weekend and next week, mostly for the lid and z-table, then I will be ready to begin assembly.  I need to buy a #4-40 and #10-32 tap also.  I’m a little nervous about drilling and taping the HDPE and acrylic since they each react very differently to drilling and can be very touchy if not done right.  Hopefully I don’t have to get Bart to cut me any replacements.

My parallel cable came in today and I was all excited about playing around my motor controller and stepper motors but I accidentally bought a DB25M to DB25M when I needed a DB25M to DB25F.  I ordered a DB25F to DB25F coupler from Amazon and it should be here Saturday.  Amazon Prime is a wonderful thing.  I built a computer that I plan on installing inside the laser enclosure but I’m not 100% sure everything will fit.  My vision is to just plug a beefy power cable, monitor cable, mouse, keyboard, water and air hoses into the back of the box and start cutting.  I’m going to order some nice toggle switches with those cool red toggle switch guards on them for the front to power up everything and a big red emergency stop button for… just in-case.  Might also mount a 20×4 LCD I have on the front for some data display.  I’m thinking it might be interesting to have a readout of water temp in the laser tube and some other stuff.

Well, the frame is done.  I’m really happy how it came together and squared up once all the pieces were connected.  It feels quite solid now.

I also did a test hole on a scrap piece of steel v-rail.  I’ve never really worked with anything harder than aluminum but it was cake.  Hole looks nice and it should be no problem drilling all the v-rails with the necessary holes.  Used my drill press from Harbor Freight, a nice set of 130 degree split point cobalt drill bits.  I have decided to use a 5/32″ drill bit for the v-rails and then a 7/64″ bit tapped to 6-32 for the aluminum frame.  I could go with a bigger hole on the v-rail but hopefully there is no need.

Also, I got some new parts for the project.  A couple lens holders, a mirror/lens assembly, a couple nice Keling stepper motors, a ColdfusionX 4-channel stepper controller and a 24V 8.5A stepper motor power supply.  Also got my cut acrylic pieces from Pololu.  Those guys are the best.  They were incredibly fast, cheap and they called me three times to clear up little issues with the file before cutting.  I highly recommend using them for any and all laser-cutting needs.  They do a lot of other stuff as well, but I can’t vouch for that since I haven’t used it yet.

I started assembling the frame yesterday and I’m making progress slowly.  Like I said before, the stuff is hard to work with.  Until the whole thing is together, it really wants to shift and move around a lot.  I don’t want to lock down any of the bolts for the brackets until it’s all the way together and square.  A few times I forgot to put brackets in channels that were going to be blocked by other pieces of frame so I had to remove pieces, add the brackets and reinstall them.  I’m in love with this frame stuff, it’s like a huge erector set.

I hope to get the frame fully assembled this weekend.  I need to stop off after work tomorrow and pick up some cutting oil, I can’t find mine and I need it to drill the holes in and for the v-rails.

Finally getting some parts so I can start working on the cutter.  Last week I received the v-bearings and skate bearings.  Today I received all the extruded frame, v-groove rails, toothed pulleys and belt.  I started assembling the frame but the stuff is pretty hard to work with.  The t-nuts want to slide all over the place so it’s like building some strange 3-d puzzle that keeps wanting to shift and get out of square.  I’ll have pictures of the assembly in another post.  For now, here are a few pictures of the parts I have gotten so far.

Oh yeah, and Misumi has a pretty amazing catalog, I highly recommend requesting one.  Free catalog, absolutely huge and chocked full of all kinds of interesting bits and pieces.  Came with a printed catalog and a digital catalog on two CD.