I am wondering if anyone else has tried to use 7075 aluminum in a bead roller to do things like a 1.5" round over or the wire edge on top of a bomber seat shell? Did you cold roll it or heat and roll? what did you heat with? How did your beads come out or did it shear? I generally thought of 7075 to work on soft radius bends like around a (air)boat hull but if you put it in a 30ton brake to make a hard chime it breaks clean, but I'm not sure how it would react in a bead roller since this would be gradual shrink & stretch as rolled , so I was wondering if someone else has tried it before I cut up my sheet of 7075 just to experiment. YES I do understand that IF i was going out and buying a new sheet of Aluminum then a softer alloy would be a better choice, HOWEVER I have about 9' of a 0.90 sheet of 7075 left over and I was thinking it would be nice to make some polished Bomber seat shells out of. I just kind of want to know if it will work before I cut up the aluminum sheet as it isn't cheap and I'd hate to waste it.
Thanks, this was my concern to. I guess I should not always think about using stuff just cause I have it Maybe this is just wishful thinking...lol
yes I agree, if I was going to BUY another sheet of material a softer alloy like 5052 or 3003 would have been much better to use however the key point was that I already have the 7075 material and do not have to go buy it. No worries about welding the aluminum I have plenty of aircraft solid rivets left over form building airboats. I think rivets would give it some more character anyway , but I guess that really doesn't matter if I can't roll the wire edge on the top of the seats
Not worried about welding it I have plenty of solid aircraft rivets to give it some character How lazy of a curve have you done in your bead roller? Where you able to use your 1.5" round over dies, how about hem dies and flange dies .........at what point when you did it was it to much and material started to crack/shear ???
You say "7075" but not the temper. 7075-T6 will only form on a large radius, -0 will form on a tighter radius but is quite soft.
sorry about that yes 7075 T6 . I guess what I am trying to get at is what are ya'll calling a "large" radius? I know it rolls a 4" radius because that is what used on the airboat hull but I'd personally also consider a 1.5" as large radius but I've never tried 7075 that radius before, so I'm just tiring to figure out what some of ya'll more experienced metal shapers consider "large" radius?
If you anneal it with a torch, you can be successful. I don't remember the exact temp but if you google it, you will probably find that. Purchase a temp stick to that temp and quench with water.
It depends on the thickness, but it'll take a 1/2' radius. Lots of springback though. Torch annealing works, but you have to be careful not to melt it down. I've done many times. You have to clean off all oil and then blacken it with an acetylene only flame, then with a soft but not intense flame,(read rosebud tip) heat the WHOLE area you want to anneal slowly and evenly with the flame TOUCHING the surface until the black is gone. If you get in a hurry it will melt The annealing temperature is only around 900 deg. F and the melting point is around 1100 deg. F.
It's little thinker then I'd like for this at 0.90 but its what I have so I guess they will be stout bomber seats 1/2" radius is way better then I had hoped for now I am motivated. I have dealt with the spring-back on this material. I have acetylene but didn't expect I could use it on this so that's a pleasant surprise , I was thinking I needed to buy one of those little map torches for softer heat. Your using a rosebud over a brazing tip for a softer flame I will try it with rosebud. when you heat up the WHOLE area lets say for example the seat bucket (bottom) are you letting material cool or working the radius in bead roller while still hot?
yep it is hard stuff , we use it for the skin old style riveted airboats and can beat the tar out of them normally bending the T bar stringers long before hurting the 7075 skin
Is it possible to layout all your pattern pieces and see how much scrap you have left to experiment with? For example, if you can salvage a 20" square hunk, you could cut a curve in the middle and have both an inside and outside curve to test roll. I've never done anything like this so I'm just thinking out loud for possible real world answers.
sure it's possible to have small scraps left over after I layout cut out the seat parts but at that point I am commented as the sheet of material is cut up. even if i where to cut off a 12x12 square I have to shorten whole sheet 12" if it doesn't work for the seat test to keep sheet square. I am going to dig through all my cut/drop piles again and see if I can find any smaller pieces of 7075 to try testing what Never2old suggested and see how I do
7 thousand series aluminum alloy does not form well cold without massive tonnages. Even O(annealed) . Its yield and tensile strengths are very high in comparison to say 2024-0 or even t3. 7075 -0 Its elongation is only 9-10%. Then there is the question of what temper is your seat material.... if its t6 to rra....uuuuuuuuuuuuuuuuuuuuugh...
I'm thinking that in the end you're going to end up with a nice pile of scrap aluminum You will have learned something from it. 1) wrong material 2) too thick 3) I should've just got the right material.
Try a test strip. Blacken with rosebud, get to a neutral flame, when soot is burned off, it should be fairly pliable. Sent from my iPhone using H.A.M.B.
I have worked as a A & P mechanic for 50 years with lots of sheet metal work on airliners that use 7075-T6 and it is very hard to cold form without cracking, especially .090 thickness. Even 7075-0, or "soft" is harder to bend than 2024-T3. It is not designed to be welded. Check the specs in an aviation manual. It is a very strong metal and corrosion proof if treated properly. It does not respond well to annealing and should be re-heat treated after forming, which is a very specialized process. All of this is from an aviation point of view. You would do better with 3003 or 5052-0 as has been suggested. Just my 2 cents worth. I am building some skid plates of the same material for my Jeep, but just keeping it flat.
These are the seats I build and sell on eBay, I use 5052... forms well for the rolled edging. Here's the links to my eBay listings so you can get a better look. http://www.ebay.com/itm/172858822262?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649 http://www.ebay.com/itm/172802792804?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649 Best wishes... Paul.
You know Paul, you should probably post this in the classifieds section instead of spamming multiple threads here on the forum