Thumper Club Forum

Technical => Project Progress => Topic started by: timbo on March 25, 2016, 07:23:03 PM

Title: Precision Engineering
Post by: timbo on March 25, 2016, 07:23:03 PM
Well, id tried everything else i could think of  :-\ And this actually worked  :)
Id bought three Smiths speedos from an add in RC, and all three turned out to have problems. One, a brand new 80mph one, had seized up completely, probably due to never being used. All three now working due to WD40 and carefull manipulation.
Title: Re: Precision Engineering
Post by: manxie on March 25, 2016, 07:47:45 PM
What you can`t see in the picture is the 3ft bar on your stilli`s for extra leverage  ;D Great job, finger looks nasty  :(
Title: Re: Precision Engineering
Post by: timbo on March 25, 2016, 08:13:31 PM
Funny thing is, I was given that large stilson years ago, and have never found any use for it. Yes, Alison and the three large dogs are hanging off the end of a six foot length of s scaffold pole  ???
Title: Re: Precision Engineering
Post by: iansoady on March 26, 2016, 11:44:15 AM
Have a look at Dennis Quinlan's web site. Dennis is an Aussie Velo enthusiast and spent his working life fettling chronometrics.

http://velobanjogent.blogspot.co.uk/2011/12/removal-of-smiths-chronometric-speedo.html

One of his tips, which I used successfully, was to heat up the bezel till you can see the O ring melting and bubbling. It will then easily screw off. It's also better to hold the body with a specially made jig locating on the mounting studs rather than holding the body in the vice.

I too have a pair of Stillsons like that but they're generally reserved for the Discovery......
Title: Re: Precision Engineering
Post by: Moto63 on March 26, 2016, 11:57:20 AM
Eh up Tim , that finger in the photo looks like it was meant to be inserted in to one of those throbbing things that were mentioned in an earlier post ;) ;) 8) 8)....hopefully on the road to recovery?
Title: Re: Precision Engineering
Post by: timbo on March 26, 2016, 01:07:41 PM
A mere flesh wound Michael, I'm embarrassed to even mention it, in respect of your own injuries. Plus it was pure laziness and stupidity what caused it  :-\
Thanks for the advice Ian. That's what any sensible person would do, but I was on a role and slightly manic at the time. It worked anyway. Will check out the link, thanks for posting.
Title: Re: Precision Engineering
Post by: timbo on March 26, 2016, 01:17:44 PM
Just read the link. I had already tried two different strap wrenches, a chain wrench, and a pair of water pump pliers. I certainly wasn't going to apply a blow torch to a speedo that was in near mint condition  ;)
Title: Re: Precision Engineering
Post by: iansoady on March 26, 2016, 02:13:32 PM
But surely applying the stillsons hasn't done the bezel any favours?

When I did it nothing was damaged at all (other than the O ring). I used one of those cheap pencil type gas torches.
Title: Re: Precision Engineering
Post by: timbo on March 26, 2016, 07:37:50 PM
There's a couple of minor marks, and i applied very little pressure, so its ok. What could possibly go wrong  ;)
Title: Re: Precision Engineering
Post by: manxie on March 26, 2016, 08:16:22 PM
Crackin job, they look great .... I love these old clocks, I think they`re a work of art in themselves  8)
Title: Re: Precision Engineering
Post by: timbo on March 26, 2016, 09:07:55 PM
Aye, just need to test them on my mates 350 Matchless, then one of the 120mph ones will go onto a G9 Matchless twin, and the others sold on. Well, that's the plan  ;)
Title: Re: Precision Engineering
Post by: steveD on March 26, 2016, 09:24:32 PM
Did you have any bits left over? :o
Title: Re: Precision Engineering
Post by: timbo on March 26, 2016, 09:40:04 PM
I would have, I'm sure, if I'd stripped them. They look well fiddly  :-\
No, I only unscrewed bezels, and removed inner complete from case. Working on the KISS principle  ;)
Title: Re: Precision Engineering
Post by: iansoady on March 27, 2016, 10:03:34 AM
They're fascinating things to work on but as you say fiddly. The trip wasn't working on one I stripped and when I foolishly took it apart bits went everywhere. Eventually I worked out how it was supposed to work (devilishly complicated) and got it back together but I wouldn't want to do it again. My fingers are too big & clumsy not to mention ageing eyes.....