Building the Division Master and modding my RT

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Divided he ad:
Right John, got it :thumbup:

All taken down and understood :)

Thank you.

Never did get near goggle.... Was kind of late! ::)

Ralph.

Bogstandard:
Nick,

I got mine from the link Dave showed. I also buy their little boxes of engineering sundries like circlips, grommets etc. plus all sorts of little bits that one needs in the shop,

You don't nomally machine the bearings, as they come very accurately moulded ID & OD and also flanged to do the job in hand, it was just that, as far as I know, they don't produce washers like I required. So I just took the ends off a standard bearing which fitted my requirements perfectly.

John

Bogstandard:
The next little stage of the RT upgrade before I get to actually fitting the stepper.

Now ths is where I change my mind from my previous plan of making my own Oldham coupling end. For two reasons, I had made a balls up of my initial calculations which would mean I would be doing finger gymnastics trying to assemble the coupling and set up for no end float at the same time down the length of a fairly small diameter tube.
The other reason was that when I stripped down to the thrust washers this evening, the wear pattern on the faces was absolutely perfect, so rather than spoiling a good thing, I decided to go with what I had.
So I cut some soft brass slugs from a bit of 2mm rod, ground down a couple of grub screws to the right length. Then it was just a matter of a slug down the hole followed by a grub screw, this will stop damage to the threads, set up the zero end float and tighten things up. It turned out perfect, no detectable end float and the whole lot turned as smooth as the proverbial babies bum.

So that left me going the normal route people would take, just fitting an Oldham coupling to the 12mm handle spigot. My problem, 1" diameter coupling, fine, 10mm bore, not good.

So a spell on the lathe with a boring bar had it opened up to the right size.

I need to mention a little about couplings such as this, especially the ones with this type of clamp system. On no account try to drill them out to size, all the cross cuts will deflect the drill, and the hole could end up almost anywhere. By boring, that problem doesn't occur, and only takes a few minutes anyway. That is a warning that should be followed unless you want to end up with a wobbly coupling.

So everything was to my liking, and it was time to assemble everything into a RT. Just a reverse of the strip down procedure, and I assembled everything with bedway oil, which will also be used during it's machining life, that is why ball oilers are fitted and not grease nipples. But again two little things I did extra.

If you notice the main clamp screw on the casting top, I have knocked the tightening finger pin all the way thru to one side, this makes it much easier to do up/undo, but the screw must be in position before the main table is put on, otherwise you won't be able to screw it into the hole.
The other, is the clamp ring that is screwed onto the end. It has four locating bolts, but also four adjusting screws that are used to remove end play in the spindle assy to RT. A few minutes spent adjusting those and the locating bolts will get rid of all end play, but still allow smooth rotation of the worm spindle housing.

Just a little mechanical marking out/measuring exercise to find the PCD of the bolt holes in this flange. It will be used when the support tube is made.

So it is now at a stage where a few things need to be made.

Hopefully that will be sometime soon.

Bogs

Bogstandard:
First things first, on the last post, I showed a bit of calculation written down on the undersheet. It said 16 PCD, in fact it should have read 16 PCR (pitch circle radius), so 32 PCD (pitch circle diameter).

I also need to apologise for little dribbly posts, I am doing my best in an attempt to get myself back into the shop, but at times I can't manage more than an hour or so, so you are seeing what I managed to achieve in that short space of time.

So now the next bit.

I am not completing the RT build up at this time, as it is easier for me to handle as it is.

I now needed to look at fitting the stepper motor to the RT. I am using one that I bought from Arc Euro, so the measurements I will be showing will be for that sized stepper.
First off, I mounted up the 6mm Oldham coupling (the other half of the one I fitted yesterday).

I am trying to keep the coupling tube as short as possible, so I marked up how much needed to be cut off the stepper shaft, a total of 10mm.

A couple of minutes with a hacksaw and his buddy, a file, and things looked just right.

Now I could get things into their correct positions and start to measure up.
The first thing was the OAL of the tube, everything else falls into place around that, and because the width of the stepper and the diameter of the flange on the RT is the same at 56mm, and because I don't have any 56mm square ali bar or larger available, I will be making a 2 part tube, loctited together when everything is lined up.

This is the sketch that I will be using. There are a couple of things that need pointing out.
The first one is that the four corner holes on the flange should read '4 off 5mm tapped holes', plus the data sheet that came with the stepper motor showing dimensions didn't quite match what I was holding in my hand, there was up to 1mm discrepancy in places, especially around the holes area, so I will be waiting until it is all assembled before spotting thru for the four corner holes.

Now there won't be any more posts on this until next week, as I am assisting Ralph over the weekend to 'fix' a couple of chucks.

Bogs

Divided he ad:

--- Quote ---Now there won't be any more posts on this until next week, as I am assisting Ralph over the weekend to 'fix' a couple of chucks.
--- End quote ---

Indeedy :thumbup: Apologies folks. Trying to get my machines sorted so that I can attempt to make something worth showing :scratch:

I suppose I'd best take a camera now that it's public knowledge?

I'll report back in a different thread on that one :headbang:

Looks like you're getting close on this too John. Sorry for the stoppage.

Ralph.

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