Engineering workshop?

Hope I haven't completely missed a thread that would answer this question, but does anyone happen to know of an engineer with a workshop with mills/lathes/cutting tools within the M25 who could take on small, simple bicycle-related one-off projects without charging silly money?

It's a bit of a long shot, but I'd rather get it done right and pay for it than attempt it myself and make a mess of it. The type of job might vary a bit, but usually similar to this one..

I need to get a (steel) rear wheel axle machined to make the flats a bit longer, which will alter the spacing, so the wheel will fit correctly without having to attempt to spread the dropouts.

Any tips or suggestions gratefully accepted.

@mdcc_tester might know somewhere

I have access to a lathe, but only recently got trained on it. I wouldn't say I was experienced, but I could take a look at the job. The problem is that I and the lathe am in Manchester, and I can't guarantee a quick turnaround. Would do it for free though, with a view to generating a small sideline in this type of work.

Some frame builders will have the tools but your problem is that one-off small jobs are crap - unless you get properly paid for them. So you might find that anyone who can do the work properly and promptly will charge more than its worth to you to do it.

If there were a #tester_FAQ this would be question two. There isn't one right answer, and the shop I use is neither inside the M25 nor likely to be sufficiently interested in small one-off manual jobs to offer a good price to somebody not already an established customer.

The generic question is "Which subtractive metal working shop (milling/turning/grinding) should I go to for my prototypes?"

The generic answer has the following parameters:

1. Find somebody as local as possible
   
2. Find a shop where you can walk onto the shop floor through the open roll up shutter without an appointment
   
3. If the quote seems high, they probably don't want the job, so try somebody else who might.
   
   

Of course, if you don't have experience you might find it hard to judge what counts as a high quote. In the first instance, the obvious question on price is whether you could solve the problem a different way for less with COTS products. If there is no commercial alternative and you still want to do that one weird trick which nobody considers worth putting into production, I'd say bicycle scale parts (i.e. not so small that they need a Swiss lathe or so big that they need an Oil Country lathe) should not be more than £10 per cut for one set up. A simple plain bushing or spacer is 4 cuts (face, OD turn, bore, part-off), so there's your bare minimum for somebody who is doing it for a living rather than a hobby.

I could have a small job for you if you’re up for it, though I’m happy to pay. Just need a tube with a specific ID and OD. To cut in half and use as a shim

Sure, PM me.

Thanks for all the information so far. Much appreciated. I went through at least three (broadly) London-based workshops where the owner/operator retired and sold up, never to be seen again. A real shame that this sort of resource is so hard to find...

In this instance, might just see if I can make some headway with a multitool and a metal cutting blade, some cutting oil, a vice and a few good files. If that really doesn't look like it'll work, I'll maybe take fizzy.bleach up on his offer..

there are men in sheds up and down the country with lathes and all sorts of stuff. put an ad in your local rag or paper shop window and you will likely find a retired old geeza with a killer workshop.

seriously though theres loads of people around like this you just need to find them, admittedly probably more in rural areas than m25

Why don't you try South London makerspace? They might have a lathe

I went through at least three (broadly) London-based workshops where the owner/operator retired and sold up, never to be seen again

Ditto, except that I got to the last one soon enough after he sold up to see the sign directing me to the current shop who had bought his goodwill, and the boss there is younger than me so with a bit of luck the current arrangements will see me out 🙂

don't know if I'm reading it wrong but how will changing the axle in anyway affect the spacing?

He's changing the spacing and he needs the flats extended so that the anti-rotation washers will still go far enough onto the axle to make it all work. I'm guessing some sort of internal-gear hub.

Oh I see. Careful use of a bench grinder will make easy work of that

Or a file.

I have a theory that any subtractive manufacturing can technically be done with a suitable set of scraping blades and enough time 🙂

if the operation is what i'm picturing, you could mark the line to which the flats should be extended on the shaft (using bluing or just scribe it on the metal), then use a file and work towards it. but smooth (i.e. ruin) the edge of the file that runs along the flat so you don't accidentally cut into that surface.

does that make sense?

Thanks for all the comments and suggestions. Will comment again once I've had a go..

I run a university machine shop, happy to do a few bits and bobs from time to time, no fancy CNC tackle but manual stuff is no issue. Up in Leeds but postage is no real issue.

Bumping this to ask: where can I get a crank remover thread (22mm) cut into a crank? The taps cost about £60 a set - but I feel certain I wouldn't get it straight, needs a fixed tooling set up, right?

I have these nice early 80s pair of cranks with matchy rings, unused, one is (strangely) unfinished. Rang the original manufacturer (Cliff at Royce) who mentioned that sometimes various old parts surface that went missing from his workshop way back when. Which was a bit awkward ... though I bought them in good faith from a well known seller of vintage bikes.

For ages I've been thinking they were stripped ... really really stripped. But of course not, there's no remnant of thread. The ID where it's missing is correct for remover threading (21mm) so this confirms it's unfinished. Also, there's a faintly rough edge at the entry to the pedal thread, so I guess that is missing a little bevelling type job too.

Please nobody say 'use a bearing puller if you want to remove it'. Mainly because I feel like that will be a bit damaging.

If you must throw good money after bad, any job shop with a halfway modern CNC VMC and a shortage of work should be able to thread mill that for the price of the tap set. Being such a short thread in a blind hole, thread milling is much the better method.

OK thanks for that, I don't know what thread milling is. Now to find

any job shop with a halfway modern CNC VMC and a shortage of work

I don't know what thread milling is

https://www.sandvik.coromant.com/en-gb/knowledge/threading/thread-milling/pages/default.aspx

Thanks, sorry I was intending on having a look around but that’s a v helpful explanation.