Member postings for old mart

The er chuck will be able to hold most threaded shank cutters you have. There are a lot of Clarkson and some Osborn holders on ebay at the moment, many overpriced. It would be worth checking out the prices and aim to pitch a bit lower for easy selling. I have two R8 osborn Titanic II holders in new condition for up to 5/8" and 16mm shank as well as a lot of cutters, and they come in handy from time to time. I also have er25 R8 which hold up to 16mm shank, mostly solid carbide which gets used most often. If you also have a lathe,it might be better to get er32 and then you could buy an er32 holder to mount on a backplate and share the er system between two machines.

Just have a small pot of oil and a little brush, about 1/4" , 6mm diameter. For steel, using HSS just a dampening each pass, and similar for aluminium. With carbide, you can cut dry with steel and maybe dampen the work for finishing cuts.

I saw that ad from RDG on ebay, I wonder if the original buyer knew how to measure runout. P B chucks are not likely to suffer from bad quality control. It is still a lot to pay for a 100mm chuck.

I feel very lucky to have picked a NOS one with both sets of jaws for £25 + £15.50 postage back in 2019 on ebay. It runs as true as expected, 0.002" tir at any size. Ifound a pic of it.

Edited By old mart on 11/02/2021 17:55:19

Edited By old mart on 11/02/2021 17:59:02

As mentioned, the motor would require changing for a 3 phase one, and you would have to do some careful measuring to find out whether there is room to fit one.

The Atlas 12 x 24 which we are getting into running order has a screw on spindle mount similar to the Boxford and, slightly bigger than Myford. When I decided to add a 160mm three jaw chuck, the chuck body had enough metal in it to enable the bore to be increased to just about 1 3/4". The spindle thread is 1 1/2", so a drawbar with a flanged end 1.74" diameter would stop the backplate from unscrewing if reverse was used. This has the drawback of blocking the spindle bore.

As already mentioned, threading in reverse using a left handed threading tool to produce a right hand thread allows you to thread away from the chuck. Usually slow speeds are used and the forces are not great enough to be in much danger of unscrewing the chuck. I would loosen and retighten the chuck firmly before doing this tye of work.

I made a much more sophisticated locking system for the Smart & Brown model A, which doesn't block the spindle, but nobody on this forum was interested in the design.

As Tony suggests, and a magnifying glass might help.

Now you mention folding, Bazyle, our museum one folds and the gib can point straight down to take up less space.

I made the R8 conversion for the Tom Senior self ejecting with a captive drawbar and it has been a great success. I could only do it because there was a convenient cavity in the spindle above the end of the tooling. Also, I could lock the spindle using spanner flats at the bottom end.

Edited By old mart on 08/02/2021 20:35:54

The look like they might attach to a large straight edge. The colour is like Jones & Shipman.

I would not recommend any modifications.

We have an identical one at the museum with the Seeley brand on it, and we managed to break it. One of the volunteers was lifting something and hadn't noticed that the gib was caught up and couldn't move as expected. He continued pumping and the main arm just outboard of the end of the ram bent until it had a 30 degree bend in it. The inner black tube also started to bend. No other damage was done to it fortunately. It just folded without doing anything else any harm. If the ram had burst, we might not have been so lucky. Our crane had a reinforcing strip already on top of the red part of the arm.

Spares from Seeley were easy to obtain and not expensive. We are more careful with it now. The bits are in my metal stock and have donated some offcuts from time to time.

I wonder if this would happen when boring in reverse with a left hand tool? I can't do the tests until the lockdown ends.

Its a shame that it is proving difficult to drill, I have not had much trouble with top quality new drills. You will also have to be thinking of whether the cast iron can be tapped, if there is a hard spot.

I once turned a solid piece of cast iron to make a chuck backplate. Part of the od turned like an interrupted cut, and I was glad to have a choice of carbide insert grades to deal with it, HSS would have had no chance.

I would vote for the old optical device of some type. There is little to stop dirt getting in to the works, so I think it would be used in a clean enviroment.

The Smart & Brown model A does it every time a small ammount. We get about 0.001" on the diameter, or the familiar helical groove if the saddle is withdrawn quickly. Don't worry about it, just back off the tool if the little extra cut is going to cause problems.

You could try them at standard fits, and if that proves too tight, just deepen the ring groove in the piston. Quad ringsare intended for use with hydraulic oil or brake fluid, so a steam engines lower lubrication and heat might be a problem. I hope there is an o ring of the same size to use if the quad rings prove problematic.

I use a 16mp Pentax K5D with the recorded pixels set to 2mp. I will see if a larger file will add to the album without causing trouble.

I have just added an 11Mb picture of a planing machine taken at the underfall yard at Bristol docks using a Pentax K3II 24 mp camera.

Edited By old mart on 06/02/2021 16:39:40

A rear toolholder for parting blades can hold any size of blade because the edge is upsidedown. You could use an industrial 32mm blade on a Myford which could not fit in the ordinary toolpost. The advantage is that the chips fall away from the work more easily assisted by gravity.

Depending on the size of your lathe, you could look at larger holders for the MGEHR type inserts. I have some of this type in 2 and 3mm for aluminium and would use them dry on bronze. ARC have small parting blade systems which are good for small machines. Try 200rpm, it might be better.

Edited By old mart on 05/02/2021 21:33:30

APT is a good firm in the UK supplying carbide cutters and all other tooling.

Oilite bushes can be bored to size, but reaming will close up the pores which defeats the self lubricating idea. I had heard it said many years ago that if a dummy shaft was made with a good surface finish of the same size was used to push the bush in, the bush material would crush slightly and the fit would be perfect. The problem of removing the dummy shaft would then have to be addressed.