So, this morning I drilled out the stripped set-screws holding the rails into the assembly. Remember, I needed to take out the rails and ballscrew and re-mount them spaced to hold the gantry. There are the offending buggers: BTW - Those machine set-screws are a bitch to drill out! I also went aluminum shopping and bought the lower cross-member that will be the base of the gantry. I decided to put the rails/slides in place (or there-abouts) to see how it looks: Holy crap, it's starting to look like something! Stay tuned for the making of the rail mounting blocks!
Alright, so I need to get the X-Axis rails mounted to the frame so I can measure and get the aluminum for my gantry. First, had to get rid of the old mount that held the rails and ballscrew in one compact mount: The, I got some small aluminum blocks that needed to be drilled out to hold the rails and be mounted to the frame. For size ref. they are 2" x 1.5". Drilling the first block, which will also be the guide for the rest of the blocks: Using the first block as a guide for all the others (I know aluminum doesn't make the best drill guide - but it worked fine). You'll notice the blocks weren't all the exact same size.
Next I needed to drill a 3/4" hole for the rails in the blocks. Now, with my little drill-press I couldn't come up with a way to make that large of a hole that would be even close to accurate. So, a friend offered to help. So, we clamped all the blocks together and drilled them all in one shot so they would be all the same. Check out that monster bit that we used. Yarr! Pictures of the finished blocks and mounted rails soon!
Got the blocks all done and the rails mounted. Got lots of time, since I just got fired from my job. It's all good though, wasn't happy there anymore. Now, back the the CNC Machine! Drilling the hole for the Set-Screw that will hold the rail: Now that they are drilled, time to tap them: All done! Look at those spiffy little blocks, you can see the rail next to them: Frame back together with the rails/blocks bolted up. Everything is perfect, square and level. I clamped the bottom part of the gantry to the rails temporarily to check clearence and movement. Glides nice and smooth too. Now, to get the ballscrew and servo mounted - and the lower half is done! Movement Video! More to come VERY soon.
wooh a 3/4" drill bit......... i didn't even know you could get a bit that big! what kinda motor torque does that drill produce to be able to drill at such a diameter?
That's nothing, they had up to 2" bits on hand - larger on their floor drill-press (which is easily 7ft tall). Not sure, but I think the mag-drill has a 1/2hp motor. They usually use it to chew through steel.
Come on dude, it's almost been a week, I really want a progress update on this beast, designing something similiar myself and your log will help me overcome potential pitfalls and what-have-you . .. Looking Good
Now I need to mount the ballscrew to the frame. The old mounting plate, for the time being, is the best option. But, it needs a few adjustments... Since it will be mounted facing the end-plate I need to counter-sink the two bottom screw holes: Now I need to drill a hole in my end-plates for the shaft of the ballscrew. My drill-press couldn't reach to the center of the plate, so I had to use my cordless. Surprisingly, it chewed through both plates with ease! Now for the four holes to mount the ballscrew bracket to the plate: Man, I love it when I measure things correctly and they fit perfect!
Now, for the other side of the ballscrew with the bearing. The original bracket wasn't the same size/shape as the first bracket. Since I drill the holes through both end-plates at the same time - I kinda wanted a bracket that would use the existing holes. Also, it would help me keep everything aligned. The old mounting bracket: Now, I don't have a way to do the flat-bottom bore in aluminum - so I decided to make the bracket out of 1/2" polycarbonate. Four corner holes drilled - now for the center bore to hold the bearing: Just need to clean it up a little: Perfect! Just like the original: All mounted up with the bearing and ballscrew in place: Of course, I will re-make it out of aluminum when my machine is running... The other end mounting utilizing the original bracket: Looking good! Now to get the gantry done! I would say I am over the hump now, maybe 40% left to go...
Well, there ya go - one nice big fat update! You won't have long to wait now to see this beast finished either...got nothing but time everyday to work on it (it's my new job!).
It's looking good mate! must say, that last update did clear up a few things about the design, much kudos I have a burning question for you though, once you have it up and running, how on earth do you calibrate the machine, how does the software know how may revs of the motor = so many mm etc Oh, and how does the software know where to start, for example, say you plonk a block of plexi slap bang in the middle of the unit, whats to say the router doesn't start at the top right edge instead of the center ? (hope you understood that lol) Cheers
Looking good. Keep the updates coming. I love the irony - you have to build the machine to manufacture the pieces to make the machine..... Well at least you have a decent work around.
Thanks, glad the build-log is helpful. There is a quite a bit of calibration that must be done in the software (Artsoft Mach3 - the best). All the specifics are entered into the software, travel; ballscrew pitch; servo specifics, etc. One the machine is dialed in and the variables entered - that's it. As for where to start - that is considered home. You can manually jog the axis to any point on the table and make it "home". So, if you plunk a 10" x 10" workpiece down in the center of the table, you would jog the machine over until it is right at the corner, set that as home, then work from their. It sounds confusing and tricky - but it is pretty straight-forward. I will be, and I reccomend doing this, testing my machine with a pen chucked in the router (unplugged!) until I get the hang of the machine and I am confident that it will do what I tell it. Please, feel free to keep asking questions - I have done a ton of research (over a year) - so I have already asked just about all the "dumb" questions! Heh, yeah, kinda "Terminator-ish" - the machine is making parts for itself!!
