Member postings for Russell Eberhardt

Or collect the water from a dehumidifier. You'll need one in the workshop given the current "drught" conditions

Russell.

I started to dismantle things to see how they worked when I was about six and haven't stopped in the last sixty years. Most things have worked again after reassembly

Russell.

That must be a tiny file. What size key do you use on a 5/32 shaft!

Russell.

John S is right of course, however I have used round keys with a bit of locktite to overcome the tendency to roll and never had a problem. If you can drill both the wheel and the axle with it assembled you can get a good fit easily.

Russell.

They said it was aluminium but I expect they use some exotic alloy, but clearly not exotic enough!

Russell.

It depends entirely on your application.

Years ago I used to use "MuMetal" (an 80% nickel alloy) for magnetic screening of cathode ray tubes as it has a very high permiability (about 100,000).

For mains transformers, grain oriented silicon steel as it has a high operating flux density

Ferrite for high frequency devices.

Etc.

Russell.

That certainly looks challenging! Bon chance!

Russell.

More likely 5/16 W.W.

Russell.

No. It goes back to the early days of the Bullnose Morris. Morris made the early engines for these cars under licence from the French Hodgekis (sp. ?) company and they had French Automobile threads throughout. The chassis used the standard practise at the time of using Whitworth threads so, as garages at the time would only have W.W. spanners they decided to use these metric threads but with W.W. head sizes.

The practise continued for some time.

Russell.

I find it amusing that pipe fittings here in France are specified by the (approximate) diameter of the thread, e.g., 12mm, 20mm, 26mm. But they are really BSP threads with a 55 deg. angle. A case of the British beating the French but the French not admitting it

I once owned a vintage Morris car. The engine used French Automobile thread (metric) but nuts and bolt heads were to Whitworth sizes!

Russell.

Thanks for the suggestions regarding pivot polishing. The finest wet and dry I have been able to get is 1000 grit. I have some rouge powder, it is recommended for non ferous metals but I will give it a try.

Micromesh looks interesting although the website is a bit confusing. They show a micrograph of 400 grit "sandpaper" beside 1500 grit Micromesh and the Micromesh looks rougher to me! However I see it is recommended for refinishing acrylic windows so I might be able to find something similar in one of the nearby boat chandlers.

I see M & P (who have an outlet in France) sell "Diamantine " powder for polishing steel in medium and fine grades - anyone tried this?

I can see some experimenting coming on. I'll try making a burnisher as Martin suggests and try various polishing mediums and see what gives the best finish.

Russell

You can find an explanation of the coding system for sizes here: http://www.ccpa.org/pdf/B212_4.pdf

Russell.

Nice one Harold. You always come up with good ideas.

My mill has X stops but no Y stops. Having seen this I must fit something similar.

Russell.

It's not cutting the gear teeth that takes the patience. It's the crossing out!  Done by hand - no cnc (yet).

Russell.

Edited By Russell Eberhardt on 19/04/2012 09:20:59

I've made a bit more progress. Wheels and pinions now cut. Will start on the arbors tomorrow. Don't have a pivot file so I will polish after turning with 1000 grade wet and dry and hope that is good enough (any thoughts?).

I have put a few photos in an album here to show progress.

Russell.

Just make sure you don't overtighten the new one

Russell.

I'd make a replacement one in steel to give it a bit more strength. I presume that it is attached to the lathe by bolts through the two holes on the left. If that is the case the damage was almost certainly done by over tightening the bolts.

You should be able to set the block up in the four-jaw chuck to face it and bore all the holes.

Russell.

O.K. just seen your second post, not quite so straightforward.  How about making a thick steel plate so that the broken part is sadwiched between the lathe bed and the plate?

Edited By Russell Eberhardt on 17/04/2012 16:42:28

This is not really true. There are die casting companies all over the place using both aluminium and zinc alloys. Do a Google search for "zinc die casting" in your area. You may well be able to scrounge some scrap castings.

Russell.

What has actually been owtlawed is the sale of new mercury barometers and thermometers to the general public. It is legal to make one for your own use or for sale to the trade. The repair and sale of antique instruments is not restricted. Hence the easy availability of mercury.

Russell.

Don't take it to a waste disposal centre. It is quite valuable. Mercury can be readily obtained from clockmaking suppliers and currently costs about £200/kilogram.

As has been said, it is not particularly dangerous in its liquid state. Just don't heat it and keep it in an airtight container. Be careful not to leave spilled mercury lying around as it can gradually release vapours.

Russell