Making bourdon tubes from pressure gauges

I would like to restore two oil pressure gauges for a 1912 car.

At this time the gauge needle was usually connected directly to the bourdon tube, ie no gearing. This meant the tube had to be very thin. Both my gauges came with broken tubes.

The editor of MEW tells me that the making of bourdon tubes for model engines was a topic on the web site a while back.

I have failed to locate the thread using the web site's search engine.

Can anyone please help?

Mike Robinson

Quite possibly this thread but we have talked about them before. If you look down the home page there is a google search box, if you type bourdon into that you will get some of the other threads too.

J

Making bourdon gauges was covered by Henry Wood in ME recently, and a different way is described in Kozo Hiraoka's book on the Heisler (and possibly the Shay and Climax)

I remember a description of of one method in ME many years back. A suitable bit of brass rod is drilled through. A steel mandrel is turned to size, and while still in the lathe the bit of brass is fitted on this, and the out side of the rod is bought down to a suitable wall thickness(I don't remember the dimensions), the tube is then removed, and a bit of shim metal is put in the bore, and the tube flattened over it by drawing it between your thumb and a bit of round bar, this will cause the tube to bend in a curve, take the shim out.

Ian S C

Thanks Jason, Duncan and Ian for your prompt responses.

The Jan/Feb copy of Model Engineer that I ordered arrived this morning. The article in it gave me more confidence in the reliability of the soldered shim method than the posts on the thread Jason suggested.

However, I do fancy trying the method Ian describes. The wall thickness obtained on my Boxford may be an issue!

Regards, Mike