Member postings for KEITH BEAUMONT

For Parting off, put the tool upside down and run in reverse. Tool set about 0.005"above centre. Works for me and never had a dig in.

Your saddle should be adjusted as Howards advice.

Keith.

I have just Googled "Arconate PC" and it is available from several sources. The chemical name is Propylene Carbonate..

Keith

A lot of high quality plastic items are made from Polycarbonate and Acetone will have a very bad effect on it.It will create micro cracks in its surface,so is not recommended as a cleaner in this instance.

Keith.

I have found several Sigma lenses in my collection to have had the "soft touch" finish go sticky.. Years ago I was given a Litre sample of an Acetone replacement called Arconate PC. It is colour and oderless and did not replace the Acetone being used. I still have the sample and tried it on the lenses and it has worked by removing the soft touch coating back to a shiny surface underneath with no damage to that surface. It was a bit messy to do, using plenty of clean tissue. I have no idea if Arconate PC is still available.

Keith

Michael,

I have contacted one of the leading dealers in classic cameras regarding this question and he has sent me several pages of a reference book on the subject of Leica thread Zeiss lenses.The problem is my lack of ability to put them on this forum. If you message me with your e mail address I can then forward them to you and you can decide whether they can be displayed.

Keith

Howard, Sorry, I quickly read the figures as 0.977"!

Michael. Their is no doubt that several Fleet street Photographers, in the 50s had a Zeiss Sonnar converted to Leica 39mm mount. In fact one of these is on Ebay at the moment for £3889. if you want to buy one. Bert Hardy was one of those. I have his life story where, I am sure it is mentioned that he had one converted. I attended a lecture given by him and he made referance to it.. I am at the moment speed reading it,to see if I can find a quote.

Keith.

Michael, Howard,

The LHS are reading from he same Hymn sheet as me. Also if you Google "Leica L39 lens thread, you get Wikipedia giving the same, although the are incorrectly calling it M39.They give the pitch as 0.977". 0.023" difference to a 1mm pitch would definitely bind with a correctly cut thread.. I have a Russian Zorki camera and lenses,classed as a Leica copy. The 135mm focal length lens is mint,unused,so no chance of wear. I tried it on a Leica 111F body and it fits smoothly,as good as a Leica lens, so they are using 26 TPI BSW..

The whole subject is confused by both "Bibles" for collectors saying the thread is 39mm x1 mm. These are Dennis Laney " Leica Collectors Guide" and Paul-Henry van Hasbroeck, "Leica A History illustrating every Model and Acccessory"

Keith.

Edited By KEITH BEAUMONT on 14/09/2021 12:50:18

I was a member of the Leica Historical Society for many years and have several shelves full of their literature. The consensus argument is from James Lager, an acknowledged expert on Leica History and author of several books on the subject. Google his name and you will get a lot of information.

I have tried to check several Leica screw lenses this morning and found it quite difficult as only about 4 threads are there. I t is easier to check a genuine Leica lens cap. This I have done and get a perfect fit for 26 TPI ,BSW..

Keith.

It is also known that early 1930s Canon (Kwanon) copies of the Leica used 39mm Metric form and would not fit a genuine Leica.

Keith.

A quick look at some of my Leica literature shows this to be a well discussed subject. The consensus seems to be that as Leica were a microscope maker and microscopes of that time used Whitworth form threads. Leica would have used what they were tooled up for and used Whitworth form.

Keith.

I have a 35mm Sonnar as well as several other Leica screw lenses. I will attempt to measure them tomorrow.

Enlarging lenses are also "Leica Thread", a follow on from pre WW2 days when Leica made a matching enlarger for the 35mm camera so that it could use the same 50mm camera lens. I have a collection of Leica literature and will also search that for information. Leica collectors can get quite excited about the slightest known facts and I am sure the angle of the thread is well known to them.

Keith

That looks absolutely superb Tug. It seems a shame to make it dirty. Good luck for Sunday.

Keith

About two years ago, my daughter had the misfortune to have a front wheel come off while driving her 2 year old Mitsubishi Outlander. At the time she was on the way to pick her son up from school and was in a narrow lane, so doing about 30mph. The car ended up in the ditch, but fortunately she was not hurt. The wheel continued down the road and was recovered by the Police later. They pointed out that all 5 bolts had sheared ! The car had been serviced by the main dealer who sold the vehical. In the follow up "discusion " we had with them they would not accept that they had torqued the nuts up above spec, but offered to buy back the vehicle for the pric epaid.This was accepted.

The day before this incident, my daughter had driven 40 miles out and back on the M4 moterway and I still feel sick when I think what would have happened if the wheel had come off then.

Peter,

I checked the RPM of the saw at full speed and got 4970 RPM. With a 2 to 1 reduction that means the motor is running at 10000. RPM, Hence my original question.

Keith

Clive ,

Thanks from me.too

Question asked and anserwed !

Keith

As there is nothing about not running it without a sawblade attached,,in the handbook, I assume the fan and gearbox provides sufficient load to avoid a runaway. When I reassembled the machine I did run it without a blade fitted, to check all was ok. I have a slow start unit fitted that takes 10 seconds to reach top speed and it did not continue to speed up after 10 seconds.

Thanks for the information.

Keith.

Redsetter,

I did say it was a Brushed motor/

Mikelkie,

In what way does a Universal motor differ from a brushed mains type?

Keith

Brian,

I was being facetious. Normaly someone comes out of the wood work to point out that such practice, whether stationary or not, is not to be encouraged.

Keith

For many years I have had a Clarke "woodworker" circular saw. Recently,while cutting some MDF,the blade decided to free wheel. A strip down showed that the final drive gear key had sheared. Fortunatly I had a spare gear box taken from a previous motor that burnt out,some years ago.. What I have noticed is that the motor speed is reduced 2 to 1 by the gearing. The blade speed is 5000 RPM, so that means the motor is running at 10000 RPM. It looks like any normal brushed mains motor. No sign of any electronics to change frequency, so how is it done?

Keith.

8 hours have past and no one has made a comment about S O D leaving his chuck key in the chuck !!

Keith