I have done several searches to no avail regarding the best bend radius to use for the top luggage area rear tube and the bottom ends that attach to "V". Sketches suggest that about a 90 - 100 mm Rad for the top and 75 mm for the bottom may do it. I don't want to make life difficult when fitting the ali to get a smooth finish.
Any suggestions appreciated

Silverfox,

While I used f/glass for my rear panel, I used the same radius top and bottom. However after welding the chassis, I decided to make panel round at top, and square at the bottom

I reckon with ally, you'd be better of with the same radii top and bottom, or square top and bottom.

I'm sure someone on here who's used either different radii or round/sq combo would advise you to do a template in card, then attach rearward part first, then, making sure it's firmly attached, you should be able to fold panel to your desired shape.

Have a look on here or elsewhere for details on annealing the ally prior to bending.

Your guesstimate for radius seems about right!

HTH

ATB

Simon

[Edited on 9/1/05 by Simon]

Hi,
McSorley gives the radii as:

Upper 3ins or 76mm
Lower 2ins or 51mm

Hope this helps
Matt

Thanks Simon, will keep the annealing process in mind - had kind of forgotten about it being beneficial on 1,5 mm ali

Also thanks Matt. The confirmation of my guestimates radii appreciated

If you can then I'd make them the same- it's gotta be way easier to bend the ali round if they're the same radius.

Cheers,
James

if you make them the same watch out for the taper of rear arches as you can end up with a gap near the bottom of the rear arch

If you can then I'd make them the same- it's gotta be way easier to bend the ali round if they're the same radius.

I'm not sure that's correct.

Bending over two different radii is the same as bending a cone, nothing particularly difficult in that.

You will find it harder to 'bend over' the panel the tighter the radius however.

Mick

I mean bending over the top and bottom edges.

[Edited on 10/1/05 by Mix]

I have an ally back panel and I used the same radius top and bottom, mainly because a plumber friend of mine only had a couple of sizes, one being too big.

There are some photo's on my website which show the top and bottom (Page 5) and also a couple of photo's of fitting the rear panel (Page 24).

Didn't use the annealing method, just used the soft hammer method.

HTH

Thanks guys - most helpful in confirming the issues ahead. Will probably try with and without annealing and see what happens. Judging from your builds I see a problem in how much ali I should leave to wrap over at the top bends.

Lee, great site and build - you must be deservedly proud. What size Mountney wheel? I have not seen the one (locost at any rate) smaller than 330 mm?