G 3 62 Smiths chronometer

[dynamic]

anyone ever changed the bezel/lens on a Smiths cronometer ?

any tips please

[dave16mct]

Gentle heat and a grip like the Boston Strangler! Or make the jig (in photos) which grips it like a huge nutcracker. Another jig made from a piece of angle iron with holes to fit the speedo mounting studs fits in the vice to hold it still. Sometimes the only way is a junior hacksaw and carefully cut just through.
Dave.

[clive]

Over the years when I used to fix speedos for club members I must have removed hundreds of chronometric bezels. I agree about making a jig to hold it steady in a bench vice, but my experience with heating the bezel was not successful. The reason they will not undo is that the steel case rusts, the brass bezel does not. When I used to try heating I managed to crack a couple of the glasses and often ended up hacksawing off the bezel. Then I tried 3 or so days in a poly bag in the deep freeze, straight out and onto the jig and with your best summer gloves undo it, if it wont go try tightening then undoing. 95+% of the time this worked for me. The coefficients of expansion for brass and steel argue it should not work but it did for me, I think it crushed the rust seal.

[dynamic]

thanks for the replys guys I will attempt removal by unscrewing with light heat first

plan B large stilsons

plan C whatever could go wrong

I will post my results

[Taid]

Wouldn't a couple of strap wrenches do the job?

[dynamic]

Hi Taid I did try using a strapwrench all I achived was my workbench rotating anti clockwise !

[Pharisee]

If you're changing it and are not fussed about the original one, I used a fine cutting disc in a Dremel to cut the rim. It's chromed brass so easy to cut. Take care to only go to the top of the thread and use a screwdriver to break the last little bit.

[MalcW]

I successfully removed mine by stretching the wrist part of a rubber glove over the bezel and then used a oil filter removal tool on it - the type that looks like a cross between a pair of pliers and a lobster claw. They sell them in Halfords.

Malc

[dynamic]

I have a result ! a delicate incision from the underside of the speedo with my dremal was enough to allow ye olde bezel to unscrew
a thorough clean of the body threads and a new bezel ( BSA/AMC replacement bezel £8 ) from classicbikeshop.co.uk
I even got away with saving the original lens and rubber insert
thanks to all for your input "happy of North Wales from a damp cold cave"