Looking for ideas concerning the use of sch40 2" steel tube for primary tubes in a roadster chassis; engine limited to about 400lbs with trans.
Tube frame set up have been used a lot,racecars of many types an hotrod. Tube wall of .125 n up,thicker for big HP with smart "X" cross that that pic dose not have. . Both box tube n round,some times twin tube each side. Lot of designs can be found with a fast hunt. I built a good many racecars with tubing" Seamless tube works well with extra stranght
Schedule 40 is pipe. 2" schedule 40 is 2.375" OD and .154" wall. Pipe and tubing are not the same thing. Tubing will be called out by OD and Wall. Pipe is not structural. You want to use DOM (Drawn Over Mandrel) tubing. Mike
Okay dismiss the sch40 description it's easier than saying 2" .120 DOM. Looking at app. a 90-100" overall length with at least three crossmembers probably four and a pair of body mount crossmembers in square tube. Again, it's using an O/T four cylinder with a five speed and tranverse leaf springs both ends. engine package expecting to be set back 12" or more from front cross member.
You claim it's easier than saying DOM, but what you announce to us, is that you're building a chassis from water pipe.
Sounds like a bit of overkill for an OT 4 with a 5 speed, unless that 4 cylinder has a power adder like a turbo or supercharger. Otherwise it sounds like it might be fun...
Using square or rectangular tubing will make the attachment of brackets much easier than round tubing construction. Don't use any pipe be it schedule 40 or 80.
I'm in Florida, not West Virginia or North Carolina. That tube I mention is driveshaft stock; not house water pipe. although i have seen a shit ton of water pipe in some old roundy-rounders.... along with rebar. I can see from history where you guys might get them confused.
Retired Boilermaker tube welder here. Pipe is measured ID, tube is measured OD. The same size tube can have any number of wall thicknesses.
There is no dimention on pipi that corresponds to the designate diameter nominal Od Id 1 1.315 1.040 11/2 1.90 1.610 2 2.375 2.067
I don't think the guys were getting confused "from history", but rather simply from the terminology you used of "schedule 40", which is always water pipe. But now that we've got that out of the way, 2" DOM tube is a great choice, but will make fabrication a bit tougher than rectangle tubing as you'll need to radius all the joints to fit. And brackets will also need to be contoured to fit round tube. Box or rectangle tubing would be a lot easier, and quicker.
Admittedly rect tube is a damn sight easier to work with. I'm hoping to get by with about eight coped joints in the round tube and the rest will be radiused square or rectangular tube. My last frame was absolute overkill for what I had intended (2" x 4" tube) and was heavier than hell. One guy said I built a nice pickup truck chassis.....
Unsure what you asking here? You seem set on your 2" round tube main rail chassis with rectangular tube cross members. I sense some passive aggression in your replies also? Folks are just trying to understand and help
What most folks do not know or get cornfused by is the fact that yes, TUBING can come in "Pipe" dimensions. We order a lot of it for cages and crossmembers. Just normal mild steel. It IS NOT the same as water pipe which is brittle
For 40+ years I have used 1 1/4, 1 1/2 and 1 3/4 120 wall DOM in the construction of my customer chassis. It works well in my bender and makes a clean looking chassis.
Intention is not a physical property. There is no fundamental difference between pipe and tubing, only a formal difference in specifying convention. Ø2" pipe is Ø2.375" x 0.154" tubing. That doesn't tell you what kind of tubing it is. It doesn't tell you what kind of pipe it is either. If, however, you know the exact dimensions, material, and manufacturing process, you can calculate what the thing could be good for as pipe or tubing or anything else, without any reference to intention at all. All it is is a certain mass of material shaped in a certain way. Pipe has beam strength, compressive strength, tensile strength, just like tubing, and not necessarily any less. Tubing has pressure burst strength, just like pipe, and not necessarily any less. The way some are talking you'd think that you could knot heavy pressure pipe by hand, or pop structural tubing like a balloon.
I bought a tubing notcher from Norther Tool about 20 years ago. It looks like this- https://www.northerntool.com/shop/tools/product_200659540_200659540 I've only used it a few times, but it works slick on tubing and pipe. Some hole saws have coarser teeth than others and axial runout so very few teeth touch at once. Noise and vibration is the result. I may get a diamond grit hole saw the next time I do any notching. Some but not all say OK for metal/steel.
NOW we're talking. That's a fantastic looking setup; I have been playing with torsion bar ideas as well... those are neat as hell right there
A lot of the circle track racers use the 1.75 x 0.120 wall tubing for their roll cages. If you know some local racers you might ask where they are getting the tubing for their roll cages.
Hot snot. That's the ticket right there. Simple, light, strong. Very nice. Shame to cover it with a body.
That tube chassis by PotvinV8 is sweet looking for sure. I'd be interested in hearing how well that rear driven alternator works. I had a '71 340 Duster many years ago, at one point the alternator, which charged beautifully at highway speed, failed to charge at idle ... I found out when I needed a boost after "cruising the main". I just can't imagine it'll charge enough when looking at the big picture ... that being said, I have no idea what the intended use is for the vehicle I just can't see it working for me, too much stop and go traffic where I live.
Guys, thanks for the kind words! The alternator mount is definetely not ideal, but unfortunately the only solution as there's no way to drive it off the engine. The plan is to run two deep cycle batteries to make up for the idle/no charge situation. The guys at Powermaster and XS Batteries are working with me on the project and that's what we came up with. Finger's crossed!
I don’t know about parts availability but have you considered driving the alternator off the rear cover of the blower? Instead of a pump the drive shaft on the gear could spin a pulley for the alternator. Potvin and others made drives like this. Or maybe lack of space is an issue.
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