Member postings for John Ockleshaw 1

My thanks to Neil Lichfold for his recipe for blackening steel.

I and my friends have used this often to provide a pleasing, tightly adhering black film like you find on some hand tools.

As well if you put cast iron in the bath, say brake blocks, you get a tightly adhering rust coloured film which is very realistic on a model.

If you do the work outdoors, wearing glasses and gloves, you certainly will not drop dead over the pot.

Hello John,

Back in the 1950's Tyler Spiral Hacksaw Blades were developed and made in England, they are very similar to Abrafile blades but longer.

They are now made by, and still available from, Bestway Products in America.

Contact [email protected]

I have no connection with them apart from being a very happy user, pleased to be able to get these blades.

John

Hello All,

If you have a deep pocket the Brown & Sharpe "Intrimiks" style of bore gauge are friendly to use and repeatable.

They have 3 points of contact, can reach down deep holes and to within 0.050" of the bottom in a blind hole.

Each one only has a limited range, you need 11 of them to cover the range 0.235" to 2.000"

John

Hello Engine Builder,

The article you remember was by D.J.Urwin starting in the Model Engineer of the 1st October 1971.

If you cannot lay your hands on it let me know your email address and I will send you a copy.

Regards, John

Hello Brian,

I do not know which of the boron steels you have used, but if it has any of the nitriding agents in it you may consider nitriding them. You can do this at home if you do not mind going to a fair bit of trouble or otherwise send them out to commercial heat treaters

Up until the late 1980's Birchington Engineering of Kent produced precision cold drawn sections in steel and other materials. They made pinion wire from 0.0625" to 0.75" diameter in steel and brass with involute and cycloidal tooth forms.

In the magazine Machinery, volume 83 for the 17th July 1953, there was an 9 page article about their products, the equipment they used to make them and the way they produced dies as well as other useful information about cold drawing.

If anybody is really interested and cannot get access to the magazine send me your email address, by PM, and I will forward a copy.

I followed their methods to make hexagon stainless steel "wire" for BA bolts and nuts, 4 BA to 12 BA.

Hello Phil

Rimex Metals (UK) Ltd make blue mirror finish stainless steel sheets from 0.55 mm thickness upwards. The finish on the back of this material is exactly similar to Russian Iron. You may find it difficult to obtain a small quantity.

Rutland Tool and Supply Co.Ltd. in America sell 0.005" thick blued spring steel shim stock in 6" wide rolls

Graham

Hello Ianmac,

I think you will find the cracking is caused by the joint design.

I was never able to get a, Austen-Walton designed, boiler for Twin Sisters completed because of the butt joint opening up as the boiler cooled.

Regards, Graham

Hello Clive,

I know I am backward but how do I go about sending a PM please.

Regards, Graham

Hello Clive,

Commander W.T.Barker described a tube bender in Model Engineer number2383, 9th January, 1947.

It is for small copper tube up to 1/4" diameter maximum with a centre line radius of 1 1/2 to 2 diameters minimum. A anchored mandrel supports the inside of the tube at the point of bending.

I made one years ago and it does a first class job.

If you do not have access to the issue I can email you a copy of the article.

Regards, Graham

Hello Rod, I use the spark eroder to make a form tool for the radius.

Take a piece of HSS say 3/32"x 1/2" and 2" long. Grind a chamfer across on end at about 8 or 10 degrees, full depth.

Clamp the HSS in a small tool makers vice, face up, at about 5degrees with the chamfer at the high end. Clamp to the table of the spark eroder.

Turn down the end of a piece of copper rod to 0.002"diameter less than twice the radius you want to form, by about 1/4" long. Fasten in the chuck of the spark eroder.

Bring the quill down until the copper overlaps the end of the HSS. Move the HSS horizontally until it touches the copper. Raise the electrode clear and advance the HHS the depth of the rounding. Erode the end of the HSS.

You can space a number of different radii across the end of the HSS

For your single point screwing tool use a tubular electrode the inside diameter 0.002" larger in diameter than twice the tip radius and the elecrode machined away until only the depth of rounding plus the wall thickness remains.

Edited By John Ockleshaw 1 on 23/09/2012 03:47:38

Wolfie, If your flat belt has a joiner in it you might take it out of the lathe and lay the joint on a flat surface. Check the two end parts of the belt are in line and not skew to one another, this can cause the belt to run off.

Rob, You may like to remake the thrust race in a steel suitable for nitriding.

Silver solder the arm, made of any steel, to it then have the assembly nitrided.

At 510 deg.C the silver solder will not become plastic and the atmosphere will prevent scaling of your job.

Graham

Sorry I seem to be having trouble with pasting the photo.

Graham

Hello Sid, thank you for your reply.

Neil, I have used ortho film to etch this builders name plate at 7/8" outside diameter and to etch a cliche to pad print the vacuum gauge dial onto a bone china disc at 5/8" outside diameter.

I find my Samsung laser printer is unable to print a 0.002" wide line dense enough to be a satisfactory negative.

Graham

Hello Sid Herbage,

What are you using for negatives please.

In Oz ortholith film is difficult to obtain in modest quantities, for use at home

Graham