I know it’s impossible to give an accurate figure, and there’s going to a big difference in price depending on whether I go through the back door and pay cash, or book it in via reception, but how much would it cost to get something similar to a pair of sliding dropouts cut to shape in 5mm stainless steel.

Sort of this shape…

…but just cut from flat plate.

Anyone here near Kidderminster able to do it at a reasonable price ?

See my other post – why two?

Can’t help with the cost but I’m thinking about the method. Does the part need the raised boss with the two threaded holes & the machined recess around the slot ? Something like this could be cut out by other methods like water jetting or laser cutter.

Good luck. Interesting wee project.

D.

You could try to get a quote through Qimtek?? Might need a business account though?

Davesport, as I said, it only needs cutting out of flat plate.
I could do it myself with a hacksaw, drill and file if it’s going to cost too much.

Scotroutes, part of the benefit of a Rohloff hub is the even spoke tension as the wheel is not dished as it is with a derailleur hub.
It would be a shame to lose that just to save cutting two plates.

Your best bet is probably going to be laser cutting, if you’re going to be happyish with a hacksaw then i am guessing you are not too bothered with tolerances. Laser will get you approx +/- .25mm. Though unless you had a friendly laser cutter might be quite pricey for a 2-off. Is anyone here working in a profiler? I don’t anymore so am afraid i can’t help too much

why not aluminium?

Waterjet cutting as an alternative to laser cutting. Cheap, accurate, no thermal effects. Either should be suitable though.

Couldn’t give you an exact price, but middlesex laser cutting in Uxbridge (not really near) didn’t charge much for laser cutting for me a while back.

Have you factored in that you’ll need to supply a dxf file of the profile, or do you want that generating too? If you have dimensions or a paper sketch etc I can create something for you.

Spark erosion is overkill for that kind of thing – laser cutting is what you probably want. I got this lot done for £45+VAT recently:

Do you have a cad file or are you intending to supply a sketch? The latter will be much more expensive than the former.

Try Highspeed lasers in Stourbridge. I use them a lot for one offs and multiples of hundreds and the prices are very cheap. I provide them with a cad file which I think keeps the cost down. They supply the material too.
I’m in Stourbridge so not far from kiddiminster and can help you generate the cad file.

Andy

Andysredmini at hotmail dot com

why not aluminium?

I’m trying to fit a 135mm hub in a 145mm frame, so they need to be 5mm.
All the aluminium dropouts I’ve seen seem to be around 8mm thick.
I don’t think 5mm aluminium would be strong enough for a tandem.

I hadn’t thought about a CAD file.
I suppose I just thought it would be like one of those parallelogram drawing things where the stylus would follow my cardboard template and the tool would cut an exact copy. 😳

Andy, that would be very helpful, thank you.
It may take a while to work out the exact shape needed.
I don’t know if you’ve seen my other thread, but the idea is to make a pair of fixed sliding dropouts which will raise the BB height of the frame and allow me to use a 200mm disc with a 160mm adapter.
I need to get some accurate measurements to ensure the caliper will line up with the disc properly and to convince myself it’s all going to work before I commit to getting them made.

If you want to try 2D CAD for free try QCAD. Its good enough for little jobs like this and has some good into videos on youtube. Well its been good enough for my simple stuff.

REACH FOR THE LASERS!

Anyone here near Kidderminster able to do it at a reasonable price ?

don’t worry about local for something that small – something fit-in-an-envelope small. There a plenty of companies that you can email a file to and get item posted back to you. I get stuff water cut by the aptly named Poseidon. Never been there (its up Aberdeenshire I think) – just email them the drawing, if its a particular material (thats not on their shelf) you want just post that to them too. I think I paid £32 each for getting stuff cut out that was 5ft square.

For only two off the set up costs for water jet cutting or wire erosion would be prohibitive. Profile milling on a cnc mill bolting through the two holes and through the tapped holes on a tooling plate would be the way to go. Take a few points on a CMM then send a cad file to the Cnc mill. 1hr to set and program and about 15 mins to mill. Add in cost of stainless plate and admin and your probably looking at £50 each at least. Laser cutting won’t leave the upstance around the slot or the material for the threaded holes, that will have to be milled away unless you change the design. You need a mate who works in a toolroom!

7075 has same ten strength as 316

Just pinch the back end in. Good to go.

I may have been drinking.

If you don’t need the bosses and upstance then that means you could make it out of stock plate. Stainless plate is gash and would need machining down to get a decent finish, but its cheap. You could use a couple of stainless nuts instead of the threads. If your not bothered about the scalloped shape any little machine shop would turn those out for you if you take BEER.

You could try these guys http://www.cofa-eng.co.uk/ looks like they do a load of bike specific stuff