cutting tubing for an exhaust collector

[audi2nr]

hey guys, i'm in the process of making a collector for a turbo manifold and i need some help trying to figure out what angles i need to cut my tubing elbows so i can make the collector portion of the manifold this is what i'm working with, it's a 3 into 1 manifold using 1.5 inch schedule 30 304ss. i cut a few pieces just by eye and tacked them up but the gaps were too large to tig :(

http://i197.photobucket.com/albums/aa219/audi2nr/elbows.jpg


thanks!

marc

[jontheturboguy]

hey guys, i'm in the process of making a collector for a turbo manifold and i need some help trying to figure out what angles i need to cut my tubing elbows so i can make the collector portion of the manifold this is what i'm working with, it's a 3 into 1 manifold using 1.5 inch schedule 30 304ss. i cut a few pieces just by eye and tacked them up but the gaps were too large to tig :(

http://i197.photobucket.com/albums/aa219/audi2nr/elbows.jpg


thanks!

marc

There were a couple guys in the supraforums thread that could answer your question. Basically it comes down to having a mill and taking 120 deg off two sides...er I think.

[CosmicRambler]

Sort of a typical type problem.

What I like to do is get something that is the same size, shape, like wood, poly, whatever that is easy to cut and play around making a "Template" type pattern.

Usually you figure it out after a few tries and you are not ruining far more expensive materials. Plus usually you can easily shape the other materials with simple tools and dial it in that way by hand to figure out what you need to do with the real stuff. Nothing like having an example in hand.

My standard approach on many projects. Let me get an example in hand first.

[Fusion1]

hey guys, i'm in the process of making a collector for a turbo manifold and i need some help trying to figure out what angles i need to cut my tubing elbows so i can make the collector portion of the manifold this is what i'm working with, it's a 3 into 1 manifold using 1.5 inch schedule 30 304ss. i cut a few pieces just by eye and tacked them up but the gaps were too large to tig :(

http://i197.photobucket.com/albums/aa219/audi2nr/elbows.jpg


thanks!

marc

There are no gaps too large to weld with anything if you have the patience for it. If you think you can't bridge the gap cut some smaller pieces of the pipe or put some extra filler rod in the gap and fuse it all together. Unless it is going to be a show piece it won't matter if it looks a bit rough. If it is going to be a show piece the weld it until it all flows together nicely and then grind it until it is polished, fill in any gaps or holes and polish it again. It is not a big deal it just takes more time. As for cutting your parts for an exact fit unless someone has some specific dimensions for you what you are doing is about as good as it gets. Unless, once again time, you take the time to cut your parts at a higher angle than necessary and then slowly remove the high end until you have a tight fit. There is no fast way to do this sort of work that I am aware of unless you have some specific plan with specific dimensions.

[presure2]

here is a great how to someone linked to awhile back, dont remember who, but i stuck it in my favs.

http://honda-tech.com/showthread.php?t=2787713

hope that helps.

[landspeedrich]

My opinion is you need to spend as much time as it takes in fitting your tubing,so that any gaps are no larger than the filler your going to use.If I have to make up a test set of headers I will (out of mild steel) than to possibly waste some expensive tubing.With the stress a turbo puts on the header,the bracing,back purging,correct filler is very important.The welding is the easy part,the prep is the key.My 2 cents