i think it also depends on the loads placed on the rivets…i would think it would have a high sheer load…but lower loads otherwise than welding…
for ease of use seam welding is a no brainer IMO…instead of messing around with chemicals…and drilling crap loads of holes…
seam welding is allot easier to get done for sure… but for example Grey just asked aobut the rocker… seam welding would help a bit but the foam would make that area almost imposible to destroy and increase the torsional regidity of a 3D area rather then a single linear point on the seam… were talking a cubed value here on the 3D X section… Rivets also don’t add heat to the two pc of sheet, the heat can add distortion and stress to the body over a vast area… (unless your willing to do a whole bunch of spots welds ) in that case riveting makes more sense time wise…
but mostly 80% of the time, it’s about personal preference. plain and simple…
hmmm, the foam does sound temting to areas prone to weather damage (underbody). rockers are brutal to repair, its seems so much easier to re-inforce with foam (which i assume is durable against the elements, correct if wrong).
i was thinking for areas such as the a-pillar/ roof, a series of rivets + a x-bar would work wonders? i still don’t see wither rivets or foam making much sense in areas such as the strut tower munts, upper and lower, seam welding still seems to make alot of sense, and i don’t believe the heat would be a factor.
in areas like the underbody, the foam almost seems liek a no brainer, didn’t even think of that, thanks! btu in some situations, liek mine, where the frame rail/ rocker needs to be teplaced all together, i don’t know how to apply the foam to restore the lost materials. i supposse there may be a brace, haven’t seen one, but maybe i’ll look.
rivets i am a little skeptical about though, even thoug u made good points, the loss of structure should in theory, have some trade offs, no? i can see it working on some areas, but it doesn’t seem like the bottom line solution, although u did not say it was. it would be interesting to see the areas where the rivets would give the maximum benefits (rad support, along the fenders, A, B & C pillars, trunk??).
Most aluminum structures are pop riveted together … airplanes, and stuff like school buses and Semi trailers.
Just FYI for those of you interested in the foam
This company was used by SCC magazine when they did a 300zx. Apparently high price line sedans like Infinitis use it from the factory.
When we were first discussing chassis foam, you couldn’t get this stuff into Canada without a few hundred HAZMAT certificates.
But now FoamSeal’s ordering page does show they ship to Canada, so maybe that’s changed since?
GreyGandalf … this might fall under the category of “Old School” tech, but have you looked into POR15?
this stuff is magical … I can’t begin to tell you how it works, but it’s like tremclad for your chassis.
I was at a show years ago when they were first selling the stuff. The guy took a rusty piece of steel that was literally falling apart in his hands. He paints one coat of the stuff on it, and starts wacking it with a hammer. Didn’t break, didn’t bend … Since then it’s been tested and reviewed by tons of magazines.
Among musclecar guys and anyone who restores cars where road salt is common, this stuff gets top marks. It’s a bit pricey, but it can save a frame, and bring a lot of rigidity back to it.
I don’t know what to make of that’ foamseal’… it’s very vauge about what it actually is and it lists no properties so you don’t know if it’s a 2-4-8lb foam… I’ve got a Canadian supplier of the product so no worries on HASMAT but that delivery system is pretty funky… have to see if I can sourse those. Anyone interested in it should go to the group buy and check out the actual specs. Por15 is also used in aircraft apps as well… but it’s heavy so it’s used very sparingly…
It’s only a 2lbs/cu/ft foam…
40% increase in chassis rigitdity apparently…
Basically it cant hold a candle to the 8lbs… Plus it’s more expensive.
This is probably the most informative post I’ve read in a while. I was not aware that seam welding was frowned upon. I have seen rivets on many “JDM” road/race cars. What about gus it ing(sp) certain spots of the unibody.
This might be a little off topic but what are the advantages of pie cutting parts such as exhaust’s or associated intake pipes? I mean you still have to use the same length of pipe.
Glad I found and joined this forum now I jus need a 240
seam welding is not frowned upon, it’s just that in some cases ( and that percentage of cases is dependant on the induviduals confidence, availalbvility and knowledge or the other options), it’s makes more sense or has a much better physical property for that specific job. For instance you wouldn’t bond a rollo cage or bond a V mount frame together, you’d weld it, ( it’s the best tool for the job), on the other hand seam welding the rocker to sain torsinal and longitudinal stiffness is not nearly as effective as foaming the rocker…
AS for wedges I use 22.5deg. pies for most of my work , fact is , getting 2-3" thin wall 6061 pipe bent up is very costly and almost no one will do under a specific total lenght. ( min i’ve seen is 20’ stnadard ) and that wa for steel. mandrel bending of thinwall requires some preheating as well, 6061 and the other aircraf grades are very suseptable to stress cracks due to work hardeneing when being pulled or elongated…
For IC’s ( in fact I’m doing it now ) complex curves the most cost effective is the wedge assembled curve…
For exhaust , mandrel is pretty easy to get ahold of in mild and stainless… unless it’s an odd size metric ID then mandrel is more cost effective then wedging, based on labour hrs. wedging does not loose you a masureable ammount of flow mind you, so if it’s being done then it’s not really any different then mandrel, for street use.
I was under the impression that pie cuts were mainly for weight savings (even though its minimal). so if u got a ride, where a fraction of a sec means a world of difference, then u may wanna pie cut aluminum (thats why u see that piping on all out race/ time attack cars.
seems like a long and tedious process for saving a few pounds, but thats the distance u gotta go to for prepping a race car.
hey mr200, thanx for the por15 link. have u ever used this stuff before? just trying to figure out what level of difficulty this stuff would be to use?
i may experiment with my vdub before letting my grubby hands touch my 240!!!
cheers
… weight savings ?? not sure if were talking about the same thing here then?
see the TB side is wedges. the tubo side is a mix… it’s easier to do specific things in certain places… in this case that triple curve on the TB side required the wedges…
i always thought aluminum is lighter than stainless steel???
all the pie cuts i’ve seen was made out of aluminum, and my reasoning was aluminum was hard to bend? i thought he was refering to setups that were made entirely of pie cuts, not mixed and matched.
I see your point though!
… I guess my post of wedges was not clear… I was reffering to the exhuast and wedges vs. mandrel … and the IC wedges vs. mandrel and why each is easier or more cost effective… yes allot of hacks around will run $5 ECT and put it into a $50 bender for IC piping and charge good money for it… but to do it right in Ontario, you either need to spend HUGE money to get each pc custom bent ( might as well buy a new car ) or use wedges… not allot of people like to do that becuse MIG and aluminum do not make for nice clean pretty welds, you need to TIG it and be steady with it … it will last forever and won’t ever burst
sorry, i was just refering to under the hood piping. i’ve never even thought of wedging the exhaust. doesn’t sound logical, but probably because i can get custom exhaust work done for dirt cheap. then again, since i can’t get the tools to do exhaust pipes myself, but i can get the tools for pie cuts, it may be cost effective after all, but time consuming (my time is $$$ y’know). again, to each their own, like u said, every application is different.
i’ve seen some real pretty sweet welding jobs done with pie cuts, and personally, i think it looks way better than SS when done cleanly (when did the hardcore ever really care about looks though)?
:shock:
well with high end street machines like the one above… it ALL looks cool and one reason is it’s all completely functional and purposly build to do a specific job … ell… also most people don’t realize just how much money the Japanese put into their cars… over here a few 1000 is pretty much it for an avg, FR street machine… most of that eng. swap and a few other key parts… usually anything beyond that on the mechanical side is moving into show car realms where they put more into paint and 30lb crome wheels … In Japan it’s not unheard of for someone to spend $60-$80K on enigne work for the R34… that just the enigne … they are frikin’ serious over there abot thier street racing and power… SO when you see a car like the one above ( although it loks like it’s probably a track car ) you can expect that the person paid healthily for the work…
I’ve never usde stainless or any mild steel under the hood for IC or coolant… anyone who does is just adding weight or has got the above said;…'hillbilly turbo kit hookup… ’
I have used POR15 on a rotten trunk. I will use it on the Charger as well. It’s just peace of mind. Not only does it conver rust and rot to solid “metal-ish”, but it also stops rust from spreading.
It’s easy to use, just a bitch to clean up after, and the fumes are … interesting.
If you do decide to use it, put a lot of newspaper down, and wear a painter’s suit. Depending on how you feel about recreational drug use, you may or may not want to wear a mask.
I think wedges look better than mandrel. I find with big diameter piping, some of the more aggressive bends look weird.
Hillbilly? I guess E-dot is the new Arkansas.
mild steel and silicone bends all the way baby!
Heh … I thought the ghetto IC/intake setups were the ones with PCV piping.
The ones with PVC are funny, simply because the longer you run PVC the more it’s going to cost to clean the carbonized styrene gas, ( which is given off by PVC at above normal room temps ~40 deg. ), off your valves… I ususally worn people using this of it. it’s up to them to be smart or not, thier choice.
and it somehow does not suprize me that you run around with a hillbilly IC setup… POR15 over rust instead of cutting it out and replacing the panel… both are just lazyman’s way out of doing the job well the first time …
Roto I’ve come up with a list of items to decrease mass front and back on the car…
Unfortunatley they seem a little exotic…
rotor
what kind of rims and size would you reccomend? for a s13 time attack car?
Okay so the usage of pie cutting/wedging is for large diameter piping where tight bends are to hard to peform. Is this a safe statement?
The Mines R34 has a pie cut exhaust. Tight bends are definately not necessary on an exhaust system.
I also understand that some material is harder to bend then others. I know for a fact that the Mine’s car has a Titanium exhaust and I would assume that Titanium is very hard to bend.
Thanks for the informative replies
can you weld titanium?
