Mock up of x axis

I finished the second x axis rail installation tonight and got it onto the table to mock up a position that they will be mounted. I checked the straightness of the rail mounting to the back of the c channel and I'm 1 degree out over the length only one and .8 degrees out on the other over the length. Not too bad, also Ok because the difference in angles is almost exactly mirroring each other. I have decided to move the c channel further over one end of the table so I can put some short extending rails at the end of the main and be able to park the gantry clear of unloading and loading of sheets. Will see how this goes later on.

Major issue is still getting both rails at exactly the right height and distance apart. I think I'm going to have to make up a jig on a sheet of braced ply that will hold the two channels into place and then weld the channels into place. Getting everything perfectly level will then be a matter of installing some levelling feet to the table. Back to the sketch books to come up with ideas for the jig.

Y axis gantry

Just figuring out the y axis gantry at the moment. What linear bearings, what do I make the gantry bridge out of, what height do I need it etc. I have worked out that I need to have the supporting bearings closer together than I first thought due to if I have them wide I'll lose half that width due to the length of the rail and where the torch is positioned. With the x rails being 3000 mm long, I should have at least 2600 in table travel. Hopefully more but as long as it will fit a 2400 X 1200 sheet of material.

I have been thinking also of buying some shorter rails and extending the table to make a drum and cylindrical cutter assembly on the end. Basically have a 44 gallon drum on rollers controlled by the x axis that will turn the drum and the y axis gantry just doing its thing. Ideally I'll also have a rotary tube cutter as well, but that is a bit away.

Plasma table part 2

Over the past 2 days I have continued with the plasma table build.  The x axis rails are made using a 120x65x6mm C section steel lintel, usually reserved for construction sites. I've used this because where the main x axis linear bearings sit, the C section gives protection from whatever Flys off the water table or any slap that may come off. It also protects the very expensive rails from having stuff dropped on it. This C also provides a surface to mount the fairly huge Mod 2.0 gear rack and again its protected and pointing downwards so nothing gets into the teeth of the rack. So the design will help greatly to keep the major moving areas clean and undamaged.

The two sections housing the rack and rails are fucking heavy by the way. These needed to be drilled 40mm up from the bottom with 50 6 mm holes to fit the linear bearing to it. Both had to be exactly the same as each other, so I turned them back to back making an even heavier i beam (couldn't find an i that looked like a beam) tack welded them together and then set about milling up a drilling jig out of aircraft grade alloy billet I had acquired from somewhere. Probably $100 of alloy used to make a jig but it was free so I felt not so bad.

My Dad is an engineer and he had this idea to use the pedestal drill and a long series drill bit. So I took his idea and ran with it. I made a whole jig, made slides and a work table out of scrap rhs lying around and attempted the first hole. Dismal dismal failure. In no way was the massively heavy pedestal drill (I can just lift it) going to keep perfectly still on the sliding jig set up.

I went back to my idea which I had drawn out on BobCad weeks in advance. Grabbed more of that amazing aircraft alloy and made a drill guide jig. With the jig in place and the linear rail held in position, I drilled the first, middle and last hole perfectly using vernier and whatever other measuring stuff I could find. Bolts were fitted and tightened and then I drilled the holes in the center of where the bolts were now. This made it secure and as far as I could tell (with the help of yet another bit of brilliantly milled alloy ;)) were exactly correct. The holes are 7mm and the bolts are 6 mm but that gives me some room to move things very slightly if I need to to get it more correct when dialing in the table once finished.

All 50 holes were drilled and it took me ages. Cleaned up the scarf and had one of those "Fuck yeah, I'm pleased with myself" moments. I split the I beam and checked everything yet again. Still pleased with myself. I demurred all the holes with a larger drill bit and then put the rail back on using my billet guage to help with the alignment. After getting RSI from doing fitting up 50 M6 bolts, washers, spring washers and nylocks it turned out absolutely mint. See pictures below. Can't wait to get the other side done in a week or so.

Project continuation

Hi all, if there is anyone still reading this blog. Anyway, that's not entirely why the blog is here. It's my outlet to get ideas onto paper, well, into words on a screen anyway. Since my last update I have finally moved back to Sydney! I've been a bit quiet on the Clubman build regardless due to getting a job which turned out I hated with an absolute passion, and a positive is that I have started designing and building my own CNC plasma cutter.

Since I last blogged about the plasma cutter idea I decided that to spend $18k on a turn key table was way too over the top especially as i didn't get made redundant from the previous job. So I have designed and built my own table and have started the design and build of the CNC axis. The table has a cutting envelope of 3000 x 1500mm, well slightly less due to the size of the gantry on the X and Y rails. Anyway, about to go up to the folks for a day and a bit of working on the table x axis. Can't wait. I'll leave with a few pictures.