What do you know about hydroforming?, Exhaust tubes Options

[ChrisFoley]

I'm sick and tired of buying from Hooker (Holley). They have had substantial price increases two years running. NO one else makes the tube bends I need in 16ga. They form them in Mexico, ship them to Cali, then to a parts wholesaler in Rhode Island, before I get them. It takes about 10 weeks unles I place a special order and pay shipping on top of their already high price. Then they screw me over by only shipping partial orders. After forcing me to order box quantities they ship half boxes sometimes.

I wonder if I could come up with a piece of equipment to form the complex bends I need for my headers, if I were to use hydro technology instead of the traditional method.
Everything I've seen so far using hydroforming is diffferent and even more complex than what I want to do.

[Brad Roberts]

I spent a lot of time investigating this path. It is something SSI wanted to do in the very near future. Nearly ALL OEM exhaust manufacturers utilize this method of forming the steel. The smallest least expensive machines where 500,000 dollars (used). This was a big chunk to bite off for something that would take 1-2 years to build tooling for. I think you have the right idea, but I'm going to guess your volume isnt high enough to warrant the purchase of your own equipment.

I would suggest however that you look into attending auctions on the east coast for a used Eaton Leonard tube bending machine.

If all had gone well with SSI.. I would have supplied you with the pieces for labor+material costs..


B

[Brad Roberts]

Oh.. please step up to the plate a make a stainless 9146 header. Knock off a S-Car-Go header and sell it for 1800$. Buy the collectors from Burns like SCG does and fab them up/sell them.


B

[ChrisFoley]

I'm going to guess your volume isnt high enough to warrant the purchase of your own equipment.

You're right about that. I have a pretty smart friend who would help me build my own equipment to do only what I want. The shapes I have in mind are somewhat less complex than the stuff auto mfrs are getting into, and I think I only would need low pressure hydro.

For starters I will look into having my own tube bender & dies, and sticking with the current fab procedure.

I might even go for all stainless if I was forming my own.

[ChrisFoley]

I believe I'm ready to shut down the general welding business this year and go all the way with the 914 and race car fabrication business.
I pretty much ran the general welding bus. into the ground anyway. Next step is to cut off the phone.

[campbellcj]

You know what I would like to learn more about -- I have seen glimpses but really do not comprehend what I am seeing -- is some of the technology that goes in to fabricating and welding the tubing and other systems in the rocket and jet engines. I know there is some pretty crazy stuff possible, and some of it is bound to be applicable to car engines in a "trickle down" kind of concept??? Most of my customers make stuff that flies (or blows up) extremely fast.

Unfortunately they search for cameras and recorders when you go into most of these places (IMG:style_emoticons/default/rolleyes.gif)

[campbellcj]

If somebody had made a top-quality SS 914-6 header close to a $1000-1200 price point, I would have bought it with no hesitation. At more like $1200-1800 I am not so definite; beyond that, I figure you would blow most "typical 914 guys" way out of the water. I personally have only seen 1 or 2 S-Car-Go headers and I am not even positive that is what they were. Not to "dis" what you guys do by any means (hey, I can't do it and never will), but $3K for some bent and welded tubing is borderline ridiculous IMHO....it's a production car after all not a 1-off which is a completely different story

[Brad Roberts]

I semi agree about the price... but tell us what the mark-up is in your software that you supply to the aerospace industry (IMG:style_emoticons/default/laugh.gif) (IMG:style_emoticons/default/laugh.gif)


B

[campbellcj]

(IMG:style_emoticons/default/lol2.gif) It depends who you ask. We had a kick-ass year in 2003 but our company has never recorded a huge profit. (IMG:style_emoticons/default/flag.gif)

Software is obscenely profitable once the initial R&D and launch is paid for. Now we have zero debt and every dollar over the monthly nut is pure gravy. I knew there was a reason I got into this crap and suffered thru the first 10 years of rocky roads. (IMG:style_emoticons/default/MDB2.gif)

I just hope it keeps up for while so I can afford my next mid-life crisis.

[ChrisFoley]

but $3K for some bent and welded tubing is borderline ridiculous IMHO

High performance comes at a high price.
You get what you pay for, usually.

[campbellcj]

Yep; I totally understand the concept. My company's products is at the high-end of our market and is complete overkill for many folks...but those who need it, really need it and the price is not a major issue.

Maybe I am just not a "qualified buyer" for the high-end headers, (IMG:style_emoticons/default/lol2.gif)

(Sorry, I just spent two days working booth duty at a trade show. The sales hat is still on.)

But like I said...if you guys can get it down into the $1-1.5K range I think you will have a legit market. Not huge obviously but hopefully big enough to make it worthwhile.

[J P Stein]

A bit about it here: http://manufacturing.stanford.edu/

[banderson]

In 3 sectences or less, what is hydroforming?

[redshift]

You boil the pipes til they are al dente'.

Use gloves.


M

[East coaster]

Chris, Have you investigated aircraft exhaust component suppliers? I know "aircraft " has the connotation of "expensive", but the only group cheaper than 914 guys are the experimental aircraft guys( I know, I is one). Aircraft Spruce and many other aircraft supply houses sell stainless and mild steel tubes in various states of bend and diameter. They may be too expensive I don't know, but you may also hook up with whoever (whomever?) supplies them?

Hey, just a thought that may be worth checkin' out. Good luck and count me in for a set of stainless 914-6 headers!

[ss6]

In my naive and so far futile attempt to adapt a FlowMaster muffler to my headers, I came across a guy who sells a wide variety of shapes. Just in case you haven't run into him yet:

http://www.headersbyed.com/

Also, for the curious, here's a site that describes a lot of manufacturing processes:

http://manufacturing.stanford.edu/

[seanery]

hydroforming uses water to form shapes with metal.
The Corvette C5 made a big noise when it switched to hydroformed frame rails back in 1997.
My Durango has hydrofromed rails now, too (2004).

You can get better, more intricate shapes with this process and they are stronger, too.

[eeyore]

A buddy of mine worked QA / training down in Hooker's Mexico plant until Holley bought them out. Perhaps he knows which machines were in use. I'll try to track him down.

[jridder]

I'm sure there are many different types of hydroforming. However, one (relatively) simple one is used to make two-stroke expansion chambers. You just take two pieces of flat steel of the correct shape, weld the edges together, then pump in water at high pressure to blow it up like a balloon.

Of course, coming up with the right shape for the metal is tricky, but once you have it you can make a bunch my laser or water-jet cutting the parts. Welding the edges is pretty trivial for a good welder. The high pressure water would require more than a garden hose though. I'm not really sure just how high the pressure would need to be. I'm sure it depends somewhat on the material.

Jonathan

[maf914]

You just take two pieces of flat steel of the correct shape, weld the edges together, then pump in water at high pressure to blow it up like a balloon.

I'm not really sure just how high the pressure would need to be.  I'm sure it depends somewhat on the material.

Jonathan

Probably a bit higher than what you can get from your garden hose! (IMG:style_emoticons/default/laugh.gif)

Mike