Metal rod bending - racks

[jameso]

No welding needed for this one Stuart, I'm trying to get a braced/tensioning thing working. Purely bent rod and cunning (ie, setting myself up to fail )

Over the handlebars and under the stem?
Had a mess around with something similar, but haven't really got the workshop facilities to do it accurately enough

I've made one of those, yes - took the idea from the Nitto bar-mount bag support. Works really well. The idea I was working on here was for a saddle pack. I've done the bending bit and got it working in a basic way but need to get back into the rest of it, the design seems to be evolving as I realise what the problems are, problems that only reveal themselves as you get a basic proto format together. All good stuff though. Much prefer working through things this way.

[thenorthwind]

Intrigued to see what you're up to James!

I've played around with bending a bit before, but don't have a lot to add I'm afraid. The last bender I made (out of wood) to do a batch of 8 shelf brackets out of flat bar only just lasted the job.

I keep thinking about having a go at making some racks though. Have you (or anyone else) found a good accessible source for tube stock in the sort of dimensions/materials you'd need for that?

[Bearbonesnorm]

Have you (or anyone else) found a good accessible source for tube stock in the sort of dimensions/materials you'd need for that?

You don't need anything exotic Dave, just mild steel. Plenty available on-line without having to buy standard issue 3m lengths.

[thenorthwind]

So there is. I hadn't got round to looking TBH. I assumed it would be tricky to find without big minimum orders and delivery charges, or paying through the nose for small quantities (which proportionately, you probably are, but it's cheap enough that it's not really a problem).

[jameso]

thenorthwind - Worth having a look at Tim Tas Rek's stuff out of interest. Non-welded racks, custom made. Interesting techniques. He mills his own bend radius tools then flattens and bolts the sections together. I like the idea of custom brazed racks but steel rod and braze is hefty. Bolted Al could be light and durable if done well. Easy to bend with the right kit too.



PS I'd post the results of my bending (er... sorry) but there's some relatively original ideas in this that I'm in half a mind to refine and get batch made in Asia if they work out. If they don't work I'll post up the failures, then over to someone else to take them on if it's of any interest.

[thenorthwind]

Thanks for that James, very interesting. I hadn't considered squashing and bolting (partly because my interest is in getting some welding/brazing practice without starting a full frame) but it looks surprisingly good - obviously helps that he's clearly very good at it, presumably having had a lot of practice.

His stuff is all stainless (8x1 tube, with 10x1 heavy duty option) - no problem with brazed/non-stainless-welded joints rusting with bolting either.

[Zippy]

Catching up with the forum again. I'm enjoying this thread, keep us posted Jameso. I've not got much to add that's not already been covered. Only thing I could think of is perhaps trying out the copper pipe (microbore/brake pipe size) to test a concept of an idea before you make a steel version - it'll just be easier to work with. Probably pros and cons to that too, and you may well be further down the line than is necessary.

That looks neat, although I really am not a fan of squashed tube then bolted. I guess with some careful thought of the directions of forces and a bit of careful tubing selection, it can be made plenty strong enough, but it's still an inefficient way of using the material and you could well get a stronger joint in a smaller/lighter tube selection if you didn't squash it. I do like a good bit of tube notching (easiest way in this application I guess would be a rotary tool with a sanding drum bit), and then a variety of attachment methods which I expect you have pretty good experience in.

(I may have missed a few points and some of this may not be quite applicable as I did rattle through this thread and I should be at work really...!)

[jameso]

^ agreed, though I do like his simple manufacturing technique. I'm just making test products for some ideas so as long as they last a few rides to get a feel for fit and function all's well. The fitting kit that came with my VO fenders has some useful bit in it, some of which I didn't use and have been faffing with in that Lego kit bodge way that kills a spare hour so easily. These on the right and some 5mm rod -

[numplumz]

Good post, keeping an eye on this.
Just made myself a basic front rack, but for speed just made the top surface out of sheet Ally, intending to make a tubed surface next winter.
Since I quit work I'm missing my endless supply of top grade stainless tubing though

[sean_iow]

That looks neat, although I really am not a fan of squashed tube then bolted.

I was never a keen on it either until I was lucky enough to see the Ferguson P99 F1 car from the 60s up close (it used to be maintained at a friends garage) and they've used the same technique for a removable member on the spaceframe. If it's good enough for Stirling Moss. I used the same method for some braces that support the steering column on my own race car as it was lighter than turning up inserts for the end of the tubes.

The rack looks really good James

[jameso]

The rack looks really good James

It does doesn't it ... but it's not my work made by Tim Tas Rek in the Netherlands. He's also brazing some of them now by the look of it.

[Alpinum]

The rack looks really good James

+1

Reading through this, I was reminded of a discussion about bolts and racks:
viewtopic.php?f=7&t=15662&hilit=m5+bolts&start=25

[/quote]
Or perhaps I'll die on that trip, thanks to a failed M5 bolt... We'll see.
[/quote]
Turns out I survived.

As you were

[Bearbonesnorm]

Kind of related ... project Death-trap required a rear guard support so i thought I'd incorporate a mini rack into it while I was doing.

It's just 6mm bar and a few bits of plate for the tabs. No bending equipment beyond a vice and a fence post and about £6 in materials. Needs grinding / polishing, then perhaps even chroming or at least powder coating. Anyway, thought this thread might be a good place for it.

[fatbikephil]

Good work. I'm contemplating a rack for my latest bolide. I've ben eyeing up pipe benders again but maybe 6mm rod is the easiest way forward....

[Bearbonesnorm]

Surprising how strong it is Phil, especially if you get a bit of triangulation in there ... I'm not expecting this to ever really carry much so haven't gone mad, yet I reckon it'd happily support a few pounds.

[fatbikephil]

I actually re-discovered this in the loft earlier:-

which I made for my first 1200 GS (to replace the naff plastic thing) incorporating the QR mounts for frames that held the alloy boxes. So I may mod it for the trumph although alloy boxes will look a bit daft on it and its unlikely I'll ever need the pillion grab handles again

[Gummikuh]

This Guy certainly knows a thing or two about metal fabrication.

https://www.youtube.com/watch?v=tdbTy9aoGt8

He is bending rods around wooden formers, which may work for you.

If not then just look at some of his bike frame making!

Gummikuh