Member postings for geoff walker 1

Hi All'

In the first post in this thread I mentioned that I was planning a rack feed for the tailstock on my lathe.

The lathe is a 1948 Myford built Drummond M type.

I will need to make a new barrel 7/8" diameter which will have to be drilled right through 3/8" dia, have a one morse taper machined, a key slot cut and a rack cut (probably 20dp).

My first thoughts were to use silver steel principally because of it's dimensional accuracy but are there better options where I will still have the same dimensional accuracy but easier to machine than s/s.?

I was taking some sizes from the rear end of the tailstock and removed the barrel at the same time. After 72 years use this barrel is still a perfect fit in the c.i. body of the tailstock, not a sign of wear. What material did myford use or use now for that matter for the tailstock barrel, anyone know?

Finally, for now, HPC sell heavy duty gears which are made from either en8, en24 or en36. Dimensionally the gear is good but I will probably have to modify it, enlarging the bore size and reducing the diameter of the boss. Anyone any thoughts on the choices above? I have used en8 and found it great to machine but is the material durable enough for what is know a hobby use lathe?

As you have probably gathered guys I have only a rudimentary knowledge of materials, any help guidance always appreciated.

Atb Geoff

Hi Ron

Looking great in brass Ron

It can't do any harm to lap the faces but of course they should be a really close fit before, lapping is only a fine finish process

Geoff

Hi Jeff

Yes I also like what Ron has done

I need to make a similar crank for my latest engine and that looks a neat way to construct it

Nice work Ron

Geoff

If my calculations are correct and working from the drawing dimensions I make it that the piston at BDC covers the inlet/outlet valve, would that be correct..? I imagined that at BDC it would be just shy (above) the valves but maybe not.

Hi Ron,

On the original muncaster engine the top of the piston is half way across the port at BDC, which is how I set mine.

Not sure it would be a good idea to cover the port completely, but I'll be interested to see what Jason thinks.

Geoff

Well done, looking good, some nice personal touches, domed nuts, studs and nuts, two piece bearing housings and brass oilers.

What sort of compressor are you using? I use an airbrush compressor and I found it lacks the volume to run this engine at high speed for an extended period. It will run it all day just ticking over but high speed only in short bursts.

Keep the photos coming Jim enjoying it.

Have a look in your mailbox I'm sending you a P.M.

Geoff

Sorry Neil,

My fault, not making myself clear.

The volume number on the PDF is correct but not the issues.

I've had some nice responses from members, thank you to all.

Keith Long sent me a really crisp and clear PDF copy of the original articles

Thanks again

Geoff

Looks good in brass Ron.

I enjoyed making the cylinder as well and like you I left it open and turned a cap to fit

You'll have fun making the standard as well.

Geoff

Hi Neil

The error is at the head of your link to the 1956 original martin cleeve articles in M.E.

The ones for the myford lathe

Geoff

Hi Old Mart, (Martin is it?)

Tell me about it, several times, something completely wrong has come in the post from ebay, and when I checked the listing, it was my misreading of the advert in the first place.

Yes I know that feeling Martin but in this no fault on the seller I got exactly what was in the advert, but as indicated earlier not what I wanted

Geoff

Hi Howard,

The 2879 issue is 12th. july 1956 so 2877 two weeks earlier?

Yes I'm interested Howard depending on price and whether you do paypal.

P.M. me Howard when you are ready

Thanks Geoff

Hi All,

I'm a little bit upset, just spent £3 on the wrong items, that's why it's just a little!!

I am currently planning a rack feed for My Myford M type.

There is a link on here to a 1956 Martin Cleeve design with copies of the article from two M.E. issues. I know I could print the article copies but I like to have a copies of the original magazine.

So from the link on here we have issue numbers 2379 and 2381 which I spotted on ebay a duly bought. Got the mags this morning and not a sign of the rack tailstock.

The correct issues are 2877 and 2879, a country mile out, grrrrrr.

Never mind, like I say just a little upset, and 3 quid out of pocket!!!!

Geoff

HI Ron,

Yes it is an airbrush compressor, got it from RDG, very pleased with it.

Only used it for running engines and it's fine for smaller models but the tank lacks the air capacity to run larger engines at high speed for an extended period.

Geoff

Hi BrIan,

Regarding the scale of the drawings there is, as far I can see, no real logic in what Julius has done.

The stroke of the engine from Muncasters original drawings is I believe 7/8" {22mm]. Julius has the stroke at 36mm giving a scale up of 1.63 : 1.

The original bore is 7/16" (11mm) and Julius has 16mm which is 1.45 : 1.

There are numerous other anomalies.

I have done PDF drawings of this engine to muncasters original sizes. If you are interested in this engine and would like an email copy let me know.

Geoff

Hi Ron,

Thanks again for your recent p.m.

The cylinder is one piece. To make it I used a method described by ETW in a series of articles in M.E. magazine back in 1957.

If you google Westbury Muncaster engines it will take you to a site www.plans-for-everything.com

Page three of his article is exactly how I made the cylinder.

It's really interesting, have a look, a little dated but for its time probably the best method available in the home workshop. Now with more milling machines and accessories a much easier task to make.

Cheers Geoff

Hi Ron,

Yes it ran ok. It's on youtube, search "mini muncaster oscillating engine"

No ring just a plain gun metal piston.

The flywheel is a stuart casting the smallest one they have 2 1/2" diameter used on the progress engine. The muncaster drawing was just a plain wheel.

I like stuart castings, they always machine really well, the 3" wheel may be around the right size for your engine?

Geoff

Hi Baz

thanks, got it, just can't see the outline of the key in the photo.

The allen screw will be probably be screwed in the threaded hole in the keep plate which stops it lifting out and also rotating.

Cheers Geoff

Hi Ron,

I made that engine but mine was to the original sizes in the Muncaster book.

J.D.W. has scaled it up.

I used cast iron throughout apart from a bronze main bearing, a bronze liner in the big end and a gun metal piston.

I have a Muncaster photo album which may be of interest

Geoff

Hi All

Looking at this image posted by Phil P some years ago, I have a question.

How is the casting part of the attachment fixed to the tailstock body.

I can't see any fixings and I assume the unpainted portion between the tailstock body and the attachment casting is the 2.125" diameter boss on the rear of the tailstock, but how are they joined together?

Also what is the long allen screw for in the casting.

Geoff

Hi George,

Did you cut/machine those frames yourself or are they laser cut.

If the former, well done, great job.

If the latter.........

Nice work George, keep the photos coming

Geoff

Hi Jim,

"Went wrong"? I can't see anything wrong, you've just put your own slant on it, which is what most modellers would do.

Yes I will let you know, need to get it finished this month, off to Australia for 6-7 weeks in early feb so need it over and done with soon

Atb Geoff