I'm looking into making a tapered air intake tube. Wanting to go from 4" diameter to 3" diameter over a 10" length.

What thickness aluminum sheet should I purchase? I have a local metal distributor who can supply my needs, only I don't know what I need....

How would I go about rolling the sheet without creating a headache? Mind you I have access to a bandsaw and welder(s), but very limited resources to making an aluminum cone.

Thanks in advance.

 

I think a 1/16" should be fine. You will need a slip roller to shape it.

 

Why not get 4", make length-wise pie cuts, and then weld?

 

fab up a sheet metal bender, then measure an 1/8'' or so lengthwise along the material and start bending.

here are some ideas:
http://www.pirate4x4.com/forum/attac...n-100_0501.jpg

http://www.pirate4x4.com/forum/gener...ication-3.html

 

My recommendation is to make a wooden form, half of what you want the end product to look like. You can cut out the shape from a flat sheet of hardwood, maybe some hardwood ply, but nothing softwood like pine. Make a template from posterboard trace it on to the AL sheet, leave a extra inch all around, that you can trim off later. Buy or make a leather wrapped slapper, clamp the AL sheet down as you go, and hammer the sheet around the buck. Repeat for the opposite half, and weld together. You might have to make segments as you go depending on the shape you want ot make.

I would talk to your metal supplier and tell them what you are making to get the best type of AL to hammer on.

 

Make a iron cone and press a 3" pipe over it with a hydralic press.

 

Excellent ideas. I don't wish to hammer form, and I'd like to keep it aesthetically pleasing. After Thanksgiving I will be contacting a local fabricator who has a slip roller. Shouldn't be too difficult with one of those.

If that guys prices are outrageous I will be looking into the 4" pipe with a length -wise cut to make one end 3". Seems like the less costly solution, but we will see after the holidays.

If there are any other suggestions I'm all ears. Thanks

 

That would work however I want a gradual taper, like a funnel. Not an expansion at one end similar to an exhaust flange.

 

your best bet is to buy a 4" diameter straight and cut and modify. it will be cheapest and you should be able to do it yourself. just draw a straight line down the length, then draw the v from 1/2" offset each side of your centerline on one end to the centerline point on the other end. make your cuts, then squeeze it together to tack weld it.

doing it in a slip roll is the next best option, but 1.5" is a pretty tight radius to roll down to and keep it consistent. it will always want to spring open and may prove a challenge to squeeze together to tack it up.

in for results!

aaron

 

http://www.burnsstainless.com/rd-300-400-16-6061-l.aspx

Found this little gem. Other than a wait for deliver this seems to be the absolute easiest option available.

 

Cut it 1/2 way up and you're there?

mild
http://www.mandrel-bends.com/catalog...teel-1536.html

stainless
http://www.mandrel-bends.com/catalog...less-2910.html

 

That would be perfect if it were aluminum.

Unless you know where you find a steel 4" velocity stack.

 

jimbo. call and talk to Adam at Columbia. he may be able to make them in aluminum

 

Will do.

 

Did you make one yet?

 

No , however I did speak with a rep at Columbia and they are not able to make the taper out of aluminum. They only offer mild and stainless.

I was told by the Columbia rep to call Coast Aluminum, so I'm now waiting on a call back from them.

It really is looking like the best option is to either take a 4" pipe and cut it down to 3" or take a 3" pipe and open up one end to 4". Either way has me cutting a pipe length wise and either adding or removing material.

 

use 4" pipe to cut down.

save you a lot of time making a peice to weld in and only need 1 weld instead of 2.

 

I too have looked into this for an intake setup. All I could find was steel tapered cones and sections.please post any updates or progress on this intake.

 

Patrick, the only way to make this tube without hacking and welding a 4" pipe is to get a sheet of aluminum, cut it to the desired length and use a slip roller. Same way Justin B made Justin O's intake.

 

Jimbo. How u know my name ? Iv been wanting to do this for a couple of years now. Among other ideas. Help me pleaseeeeee

 

i have used these when making stepped intakes. Maybe they can help you out too.

http://www.racepartsolutions.com/ind...part-solutions

 

^^^ that's what I was looking for originally... I'm gonna have to call them and see if they can make a specific length taper!!

Thanks screaminvtec!