How do you guys cut your flanges??
 

Hey guys, i'm wondering how you guys cut your exaust manifold flanges for your custom/log style manifolds? I know there are people on this board that sell them, but i'm not looking to buy, i want to make one myself.

Now i know one could use a plasma cutter and chop out 3/8 to 1/2 flanges in no time. But simply said, i don't have upwards of 2-5 grand for one, and don't know anybody that has access to one. Therefore here are my options for a cheap method to cut flanges ( 3/8 to 1/2 inch), and they don't have to be pretty, they just have to get the job done:

1. Metal bandsaw from harbor freight (cheap 200 dollar one), or some sort of cheap JET bandsaw.

2. Chop off saw or angle grinder with cutting disk ( dangerous as hell if that disk fractured and turned into shrapnal.

3. Oxy/aceletane flame cut

4. Jig saw, sawzall, hacksaw, blah blah blah

And for cutting the holes i would probally buy a small drill press with a bi/metal hole saw set at the lowest speed.

So give me your opinion on the best and cheapest way to get it done. ;D

Re:How do you guys cut your flanges??
 

just buy one.I have seen them on ebay for no more than $25.

Re:How do you guys cut your flanges??
 

just buy the flanges, roadrace. or something I think they lazer cut

Re:How do you guys cut your flanges??
 

Yeah i would for my car at least, since like most other people here have a honda. But what if i want to build a turbo manifold for my buddies 1976 toyota corrola?? I doubt roadrace or any other companies would carry flanges for that corrola's engine, lol.

Like i said earlyer i want to make one myself! I love having the satisfaction of building something entirly from scratch. Being able to turn hunk of plate steel a few fittings into a peice of art is just ------- great. ;)

Re:How do you guys cut your flanges??
 

building an exhaust manifold from scratch is a bitch. i'm on my second one, but i use a mill. the cheapest way for u would be a band saw, then use a whole saw on a drill press and widen the wholes accordingly w/ a die-grinder. good luck oh yeah be sure to bold the flange down perfectly flat when welding the pipes on or it will flex and won't seal.

Re:How do you guys cut your flanges??
 

This is what I did:

1-On a 3/8" thick plate I traced the exhaust gasket with either spray paint or a scribe.
2-Take the material to a drill press.
3-Using a 3/8" drill bit, drill holes along the outline of the trace. Not exactly on the line but enough so that the finished hole is 1/16 - 1/8 from the line.
4-Use a jig saw with a metal blade to cut between the holes
5-Use a 4/12" grinder to smooth out the "jagged" edge to the outline of the gasket
6-Do steps 2-4 for the inside holes
7-Use a die grinder with a carbide burr to smooth out the inside holes and some tapered abrasive rolls to finish it off.

You can get the tapered rolls from a porting kit. If you need more info. IM me.

Re:How do you guys cut your flanges??
 

Sweet, thanks for the info! I was thinking along the lines of that once too, but never attemted it. Do you think i could just use a hand drill and run it at a really low rpm? I'm thinking the drill might overheat as a result of doing that, hmmm. Anyway i'm sure your method would take a LONG time, but hey if it gets that job done in a day i'm happy.

I will pm you if you you don't want to reply to this thread anymore, but i bet it would be helpfull to talk in this thread, as i bet there are others who want to make their own manifolds, but can't afford the expensive equipment. ;D

Re:How do you guys cut your flanges??
 

I bought 2 different 5 bolt flanges that neither fit so after the money and frusteration I went down the street to a machine shop and bought a 4x6 piece of steel. He charged me 3 dollars....i took a sawzaw and cut the basic square shape.......didnt need to cut it exact just as long as it sat flush on the exhaust side, drilled the holes and had pipe welded to it. So after 3 dollars and a couple hours of work...it was easier then spending the 25 dollars....the 2 times i did...

Re:How do you guys cut your flanges??
 

Hirostyle:

You can do it with a hand drill but it will, of course, take longer. Not only that, your hand will get tired and sore. You can try that and it can be done in a day.

Here is an interesting article.

Re:How do you guys cut your flanges??
 

Sweet, thx spiceisler :)