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Bending aluminum?

Hi ya..G.
Bending 1/8" Aluminum will fracture/crack if you bend it 90 degrees..It will be rendered very weak at that fold point.
It can of course be welded at that fissure, dressed up and such, but it will add to your time & effort....needless to say one must be skilled & have the right equipment to weld aluminum.
Uncommon Aluminum alloys may not fracture when bent that much but of course they will be VERY resistant to bending.
________________________________________Rick....
 
Richard Ellis said:
Hi ya..G.
Bending 1/8" Aluminum will fracture/crack if you bend it 90 degrees..It will be rendered very weak at that fold point.
It can of course be welded at that fissure, dressed up and such, but it will add to your time & effort....needless to say one must be skilled & have the right equipment to weld aluminum.
Uncommon Aluminum alloys may not fracture when bent that much but of course they will be VERY resistant to bending.
________________________________________Rick....

I was going to try and bend it over say a 3/4" radius. Do you think that is doable?
 
Hi Gavin,

1/8 inch is a little under 3.2mm thickness. I have had chassis made out of 3mm aluminum plate and bent at 90 degrees all over the place. So it can be done, albeit professionally. I have attached a photo. You can the 90 degree bend on the top shows no fracturing at all.

I did have an chassis made earlier out of the same material where there were very small 'stretch' lines along the bend but they were very superficial and from a structural (amp building) point of view irrelevant. They were invisible following electroplating which may give you an idea of how minimal they were.

Don't know if this helps any but perhaps gives you some confidence that it is not impossible!

Cheers,

Rob
 

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jlsem said:
If you have a table saw, you can set a nonferrous-metal sawblade at 45 degrees and score the back of the bend with a vee-shaped groove about 1/3 of the way deep. You can then easily bend the plate at that point.

John


John,

Would TIG welding or soldering the inside of the fold to increase the corner's strength make sense? Cosmetics would not be affected.
 
The tighter the radius the greater possibility for fracture. T6061 is probably one of the worst alloys to bend. It can be done how ever if one is willing to accept a larger radius bend. I would highly recommend taking it to a metal fab shop and giving them $5 to bend it using the proper top and bottom dies to eliminate stress fractures.
 
Rob11966 said:
Hi Gavin,

1/8 inch is a little under 3.2mm thickness. I have had chassis made out of 3mm aluminum plate and bent at 90 degrees all over the place. So it can be done, albeit professionally. I have attached a photo. You can the 90 degree bend on the top shows no fracturing at all.

I did have an chassis made earlier out of the same material where there were very small 'stretch' lines along the bend but they were very superficial and from a structural (amp building) point of view irrelevant. They were invisible following electroplating which may give you an idea of how minimal they were.

Don't know if this helps any but perhaps gives you some confidence that it is not impossible!

Cheers,

Rob


Nice chassis.
 
Hi.
Bending 1/8" ali will not be a problem. Things to keep in mind:-
I assume your chassis will have bends of 12" length or greater,
as stated, these will be done probably in 'V' or 'form' tools, consider putting some thin plastic sheet in first to stop scratching.
3/4" rad is big and should present no problem of cracking, but ask the shop to bend a test piece of the same material first, they will not mind. If you like colour possibly use anodising grade material, the colours can be fantastic. The developed material length will depend on the final bend radius, and material stretch. (test piece could be used). You could probably do smaller lengths in a large vice but it's not easy to get dent free consistant results.
Hope this helps.
 
G said:
Has anyone here tried bending 1/8" aluminum when building a chassis?


Just take the job to a pro, and carry a sixpack in your left hand.

Any reasonably skilled craftsman can bend something as simple as a chassis to perfection, with ease.

What you do need to know, is the type of alloy. Much too often people think that aluminum is just aluminum, and grab the first piece that seems big enough for the job, that's a no-go for bending, machining and anodizing.

Magura :)
 
Rob11966 said:
Hi Gavin,

1/8 inch is a little under 3.2mm thickness. I have had chassis made out of 3mm aluminum plate and bent at 90 degrees all over the place. So it can be done, albeit professionally. I have attached a photo. You can the 90 degree bend on the top shows no fracturing at all.

I did have an chassis made earlier out of the same material where there were very small 'stretch' lines along the bend but they were very superficial and from a structural (amp building) point of view irrelevant. They were invisible following electroplating which may give you an idea of how minimal they were.

Don't know if this helps any but perhaps gives you some confidence that it is not impossible!

Cheers,

Rob


G said:



Nice chassis.


Thanks Gavin,

It finished up very nicely - I have posted before but can't turn down the opportunity to show the finished product again.

Cheers,

Rob
 

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Would TIG welding or soldering the inside of the fold to increase the corner's strength make sense? Cosmetics would not be affected.

I'm sure it would. My suggestion was meant for the home diyer who wants to make a thick chassis easily himself. Obviously it can be done by a professional but I doubt a six-pack of beer will cover the cost.:)

I would suggest using unalloyed aluminum. It's what I use and it's very easy to work with.

John
 
A polished tig welded chassis would look sweat .
You could always anneal the alloy with an oxy before bending .
Alloy works harden as the grain gets compressed.
Rub soap on the alloy when it turns dark brown its annealled .
At trade school we had to learn how to oxy alloy ,now thats fun.
T6061 is over kill for a chassis 5000 grade would do .then get it hard anodized in any finish.
Rob very nice chassis work .
 
I've always spec'ed 5052-H32 for bent sheet metal parts. It can be bent with pretty small radii. If you go for something harder like 6061 you need big radii or it will crack.

For unbent sheet or machined parts I've always used 6061-T6 or 6063. It's stiffer and stronger and machines better.

I've never used the dead soft alloys like 1100-0 but thye're like butter, so should be able to bend well. Not real strong, but at 1/8" probably not an issue.

Here's some info from a sheet metal nendor I used to use to manufacture chassis showing the common "shet metal" alloys:

http://www.precisionsheetmetal.com/home/materials.htm

Pete
 
pmillett said:
I've always spec'ed 5052-H32 for bent sheet metal parts. It can be bent with pretty small radii. If you go for something harder like 6061 you need big radii or it will crack.

For unbent sheet or machined parts I've always used 6061-T6 or 6063. It's stiffer and stronger and machines better.

I've never used the dead soft alloys like 1100-0 but thye're like butter, so should be able to bend well. Not real strong, but at 1/8" probably not an issue.

Here's some info from a sheet metal nendor I used to use to manufacture chassis showing the common "shet metal" alloys:

http://www.precisionsheetmetal.com/home/materials.htm

Pete

Do they do "one off" work Peter? I only need two chassis pieces.