Now that I have got the mo'sickle engine out of the way, rather than continuing with the Halo build at this time, I am going to concentrate on getting my workshop backlog cleared. All those round tuit jobs that keep getting put off forever.
In fact, this one has only been bubbling in the pot for about a week.
I bid and won these just over a week ago, when they were advertised on ebay. I knew nothing about them other than they were some sort of v-block. I didn't even know what size they were, as there was nothing to judge the scale by. Anyway, eventually I picked them up from the seller, who only lived a mile away, and with quick pick up discount, I gave him 20 squid, a handshake, and one of my toothless smiles.
When I got them home, I realised that I had something out of the ordinary. Beautiful hollow cast iron castings, and the detachable clamp arms were of cast bronze. Sliding faces were all hand scraped, and slid like they were on bearings. They both had the same number hand stamped into the base, so I suspect they are a matched pair (well I hope so, because I have based the machining routine on that fact). It looks like they have come off some sort of precision machine, as it has a v-way fitting cast and machined onto the base.
So now you have had the wherewithall, I am going to show you what I did to these little beauties.
First off, I wanted to get the bases flat and levelled off. So with a big carbide edged chopper in the mill (the one I showed you when I started to sharpen my own tooling), I set to work. Nothing with too much precision, that comes a little later.
This was half way thru, about 10 minutes for each one.
Both were roughed off the same.
The hold down hole was centred for each one and a 12mm milling cutter was wacked thru to open it up to a standard size. I used a cutter instead of a drill because over the years, the casting had formed a very hard skin all over, and if a drill was tried, I suspect there would be trouble trying to get it to penetrate.
Now comes the precision stuff.
The two castings were located onto the mag chuck of my small surface grinder. The scraped faces were put down onto the table, and I will be grinding the faces I have just milled off. As you can see, it was a very tight squeeze, with only 1/2" overshoot of the wheel at either end.
I only had to put a 0.0015" grinding cut on and it cleaned up both pieces just nice. A little bit of an imbalance showing in the surface finish, but that can't be helped, as I have no way of balancing the wheels. You have to remember this is a very basic machine.
Next up was machining up some commercial hold down fittings. I always have these in stock, so when a new bit of kit comes into the shop, I don't have to go rooting about or making them. All I have to do is to machine them, so that they hold things down correctly.
Bolted down to the table. A perfect match for the table spacing, it was as though they were destined to be used on this mill.
This is how they work, but you have to imagine that there is a longer distance between the two. It definitely looks like they were designed for holding something like a crankshaft, with the end journals in the V's, and the crank webs hanging down.
I suppose eventually I will make some soft blocks to fit onto the end of the V clamp screws, and if I was really pushed, they might even get a coat of paint to match the mill, which is now their new owner.
One done, lots to go.
Bog
