i need bending info

[Blown S-10]

i tried fixing a part for my truck. well, i ended up screwing it up, to the point that it would be easier to build a new one. this is ok by me. but i need to know how to make the bends i want. see pic. what it is : .070ish 6061. bent to about a 1" radius on the corners. i had a hard time coming to the finished piece in the pic. took me 3 pieces to get a good enough one, about a 1/16" error margine. which isn't bad for this piece, hard to see that just by looking at it. the hard part getting the bends to start in the right spot to make the box square.

so, if you KNOW how to get good accurate bends of this type. to make a square box. let me hear em !!!

[dyn88]

your not going to get 6061 to bend like that and survive the vibrations of a running motor. That said you can weld the shape in apropriate round stock to your bench with a piece of bar stock close to one of the pins to hold straight for a starting point then heat gently with o/a or mapp torch(be very carefull the 6061 will crack if heated to much) and with light pressure pull the material around the pins. Or cut flat pieces of the 6061 and cut 1/4 rounds of apropriate tubing and weld the radiuses to the flats. the later of the two choices would be easier and more acurate though.

[Paul Seaman]

Those corners look more like 1/2" radius corners but in any case, I would build a jig for the box out of round bar the size of your corner and weld them vertically to a piece of plate, 4 corners and roll the metal around the bar stock.

You already know the length of material needed so mark the corner positions with a marker and bend the marks exactly on the vertical posts. I have bent scrolls this way but not boxes.

Hope this helps,

[Paul Seaman]

Sorry Dyn88 didn't mean to repeat,

Peace,

[Blown S-10]

i know as a fact it will hold up. its allready been tested/used. tig welding it would just make it better. that was my goal. i tried removing a few inside pieces to replace them with heavier pieces. thats when i messed up the outside of it.

i have a jig to use, the same one i used before. though i think i will make a better one. from this project i learned about heating aluminum, and its effects.

welding flats to pipes would work ok. but a TON of finishing would be needed to make it look as one seamless piece = probably a can-o-worms.

1/2" radius. yeah, i guess it could be. i don't know. i was refering to it as i used a 1" bar to bend it around. whats the proper term for what i'm asking about ?

anyway. what i want to know. say you want a 6" square box, with the rounded corners. how do you measure, and clamp in the jig, to get a square box ???

[Paul Seaman]

S10: I am trying to describe a difficult idea and I appologize if its not clear. Basically I would say its like building a skeleton of a box out of round bar and a top and bottom plate weld them measuring corner to corner and accross the flats measure-measure-measure, tack the round bar posts to the bottom check the measurements. Then tack the top plate and check the measurements corner to corner and side to side, diagonally and then final weld the skeleton box. Bend the Aluminum around the skeleton, lift it off and clamp and weld the bent box.

I can picture the process but that doesn't help you at this distance!

Hope this is enough,

[Revlimit]

Blown...looks fun...On bending 6061, it's generally accepted that you don't try to bend it much. Its nature is to microcrack when you stress it. In your case though, since there is very little load on the part and the extensive polishing has removed many of the stress raisers, your part will likely survive. As far as fab of the box goes, how are you bending the radii? By clamping to your jig? If so it may be easier to build the box in two pieces and welding a seam where they join. This only gives you two welds to clean up as well as the ability to adjust each side with a grinder, mill, etc. I can't really see too much from the pic or I think I could help a little more. Good luck, and nice truck. Rev.

[Bulldog]

Blown,
Does it really need rounded corners. I've built sheet metal intakes for some super mod pulling tractors and they had square corners. Worked great! The piece in the pic looks like it is a piece cut from an extrusion. I bet you can find a peice of square tubing and cut a piece from that... What do ya think?
Bulldog

[jolane]

Just a thought, you said 6061, but Why? Usually, and correct me if I am wrong, aluminum sheet metal parts are made from 5052 (H-36). This aluminum is softer, and possibly harder to polish for that reason (but I have never tried to polish it). It WILL definitely bend easier and not micro crack like 6061.
As for a jig, how about a wood form instead to work the metal over? Even maybe a simple T-dolly to bend the corners around.
The length of the sides of the box should not be very hard to figure out once you have a test bend complete. How about marking the flat stock first (with graduations) and then bending the test piece. This should give you a good idea of the size required. Better yet, use geometry and calculate the mean of the box. The center of the thickness should remain a constant length from flat part to bent part.

Just some ideas to think about,
Joshua

[DIESELADAM]

Just a guess, but you said the thickness is about .070? Possibly you could try annealing the aluminum to get the bends you are looking for. I'm not sure how 6061 takes to the annealing but maybe?

[burninbriar]

If you have a press in you're shop you can make a simple set of dies by welding two pieces of round stock side by side about 1" apart for the bottom die and use a single piece of round welded to square stock for the top die.Center the piece to be bent on the bottom die and press the top die into it.You can use the old piece as a guide for how far apart to space round stock on bottom die.
Pete

[Blown S-10]

you guys have some interesting ideas. never thought of making a jig to bend it around. pjseaman, i understand what your taking about, GOOD idea. but my limited resources would make this harder than the part itself. the block of wood sounds good. a 6x6" routered block and i'm ready to go. making 2 pieces and jointing them is a good idea also, this could be plan "B".


jolane
"The length of the sides of the box should not be very hard to figure out once you have a test bend complete. How about marking the flat stock first (with graduations) and then bending the test piece. This should give you a good idea of the size required. Better yet, use geometry and calculate the mean of the box. The center of the thickness should remain a constant length from flat part to bent part."

this is exactly what i was looking for. and this is how i did the one in the pic. but it was a trial and error thing, mostly error. i'm looking to do it easier this time. and not waisting metal.

to be honest, i don't remember if its 6061. it was a few years ago i made this part. just assumed it was, as thats about all i work with. i told the guy what i wanted, and he gave me what it is. i will check to see if i can know what it is. but i have bent 6061 before.

Bulldog
no, it doesn't need to be rounded. i could easily weld a square box from flats. but i like the rounded look, a LOT. yeah, i bet there is an extrusion of just what i need. but GOOD LUCK trying to find it at anywhere near a fair price.

thanx for the ideas guys . more are welcome

[Blown S-10]

lol. i just had an idea. how about using that box as a jig, its allready made and of the right size.
hmmmmmmm, maybe plan "A"

[Leons2003]

If you have a press in you're shop you can make a simple set of dies by welding two pieces of round stock side by side about 1" apart for the bottom die and use a single piece of round welded to square stock for the top die.Center the piece to be bent on the bottom die and press the top die into it.You can use the old piece as a guide for how far apart to space round stock on bottom die.
Pete

Back in the day at the fab shop, we created a radius die typical of you idea.
For the top die, we welded pipe to flat bar, bottom die was a normal but wide(was used for breaking thick sheet) 90° female die. Adjust the press break for
the thickness of mat'l. and "press on". We used this for creating rounded edges for SS counter tops, etc.
You could do the same w/your press, making the bottom using 1/4"x 2" angle, top same idea. However, with this method you will not be able to created a ONE piece box due to the piece smackin the top die/press. Could do a two piece and weld up the joints.
For me, I would want the folks to see my handy work w/it welded at corners,i.e., rocker covers, manifolds, etc.
Good luck
L*S

[Bulldog]

Hey Blown,
Back in the day I was a foreman at an aluminum extrusion company. I was in charge of three presses. I still have some friends in the bizz. If you get me the size of the thing I'll do some askin' round...My e-mail is [email protected]
Bulldog