Defender custom aluminium roofrack mounts

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Originally Posted by roverrescue

With Aluminium its never about weight but it is about fatigue.

Your sexy angled 6mm plate has a nice HAZ that will be a weak spot.

With 100kg on a rough road over a few years I can see that collapsing???
Simple gussets would support it better.

The reason alot of manufacturers use steel brackets on Aluminium racks is beacuse ally dont like rattling and rumbling too much. It fatigues and fails with cracks running along the HAZ.

Anyways,see how it goes...

S

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Yer im worried about the welds cracking after long trips and tracks etc.

I don't think that they are going to have a hard life as such. But maybe gussets will pro-long the life of it.

I'm no professional by any means either. I just enjoy tig welding, so any advice I get, I take!! Haha

If it were mine.

I would cope in a piece of 50x25 by 3 on flat on the inside of each leg. Welded to the 32mm bottom rail and seam welded along the inside of the plate bends.

I would also put longer bolts through your tapped holes that allow a tapered washer on the back and a locking nut... so that when the threads strip out of your plates you can keep tension on the clamp.

But thats just how I would fix what you have done... from the get go I would most likely chase my tail differently

Ally welds crack - chase em - brace em - strengthen them - just keep welding em

S

Quote:

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Originally Posted by roverrescue

If it were mine.

I would cope in a piece of 50x25 by 3 on flat on the inside of each leg. Welded to the 32mm bottom rail and seam welded along the inside of the plate bends.

S

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Not exactly sure what that means lol but if I said, take strips of the 6mm plate and weld them in on either side of the welds, would that make since and be correct?

That would work too. But tie it in to the 32mm round bar of the bottom rail.

I fear you tapped holes will pull using those machine screws

The idea of making them long enough for washers and nuts on the back is a good back up.

I guess if your friend is happy - just run with it - see where it fails - learn and fix it

S

Quote:

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Originally Posted by roverrescue

That would work too. But tie it in to the 32mm round bar of the bottom rail.

I fear you tapped holes will pull using those machine screws

The idea of making them long enough for washers and nuts on the back is a good back up.

I guess if your friend is happy - just run with it - see where it fails - learn and fix it

S

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I think i know what you mean. And there was a bit of thread out the back, so will try get a nut on it.

Quote:

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Originally Posted by roverrescue

If it were mine.

I would cope in a piece of 50x25 by 3 on flat on the inside of each leg. Welded to the 32mm bottom rail and seam welded along the inside of the plate bends.

I would also put longer bolts through your tapped holes that allow a tapered washer on the back and a locking nut... so that when the threads strip out of your plates you can keep tension on the clamp.

But thats just how I would fix what you have done... from the get go I would most likely chase my tail differently

Ally welds crack - chase em - brace em - strengthen them - just keep welding em

S

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roverrescue,

I am more of a graphics (pictures) person and about all I understood was longer bolt and lock nut. Have you got a drawing tool? I use Microsoft Paint, it comes as part of Windows, easy enough to knock up a few lines.

do you want a dxf? just being an ass

Too many options on how I would jigger this design
I think aesthetically 50x25 would look okay inswide those brackets
But until I saw it in person its hard to say.

I just would have done it different from the get go???

S

Quote:

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Originally Posted by roverrescue

do you want a dxf? just being an ass

Too many options on how I would jigger this design
I think aesthetically 50x25 would look okay inswide those brackets
But until I saw it in person its hard to say.

I just would have done it different from the get go???

S

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Yer that was my third and most simplest design. I wasn't putting anymore brain time into it haha It should be sweet, i'll chuck some gussets it next time he's around, other than that, it's about as good as it gets.

At least you've given it a good crack Aus. :D Always easier said than done