While flipping the rearend under my '50 F1 I decided to take some pictures and post it. I know theres a thousand ways to do this and since I've contibuted very little in the way of tech (OK, nothing) since jointing this merry band of hot rod misfits, here goes. First, go to your local big truck driveshaft shop and get a piece of 5" tubing used in making driveshafts (They'll usually give you a "drop", you only need 5-6"). Its top dollar steel, very strong and welds nicely. Measure your frame width and cut, then cut that in half, from there you have 2 very nice "C's". Put 'em in your frame rails, soap them out and cut with your favorite flavor of tool, mine being the trusty gas-axe. A little cardboard pattern later to make your boxing for the inside of the rails and your done. I usally drop the rearend back outa the way to grind and clean up my welds, but that depends on how nice you want it to look, or your "out of position" welding skills, (which the older I get the worst they are). A few evenings of working till drunk-thirty and bam, you got it, hopefully for free! Hope somebody can use the info, later...
Im doing a 32 frame right now. last night I cut the c section out with a borrowed plasma cutter and started welding in the plates. I was lucky and found a piece of round tube about 3/16 wall laying around at the shop where i work. I hope to have mine done this weekend but i need to finish welding and grinding . it needs to look good cause its a highboy. Im also adding a gusset from the rear shock crossmember along the top of the frame just because i did a fairly deep C to get the car really low with no worried about bottoming and I just dont want any problems. ill have to take some pice when i get done and post em....... good post... Dave
Good idea with the gusset. I always worry about guys turning a 5 or 6" side rail into a puny pice of 1 1/2" box. Especially when the leaf holding the car or truck up mounts a couple of feet behind it. Just something to consider.
exactly.. thats why im doing it. Its going to run parallel with the top rail but its also 3/8 thick just to add that little cushion of ridigity over the c-notch. like I said earlier ill get some pics after i get er done... dave
One mistake that I made was to square the notch with the side of the Deuce frame. The axle tube doesn't cross the frame at a right angle. I wish I had aligned the notch with the axle center line. It's more work but worth it in my opinion. I may be anul about it but the C notch should be square with the axle center line and not the side of the frame. This won't be a problem with most later P/U frames.
not to be an ass but looks like the frame was cut more than half why threw (looks like 3/4 to me) and with a leaf spring suspension and a few big bumps that frame could bend.nice work thow
as soon as I figure how to post photos I will do a tech on my frame step. using 1/4" cold rolled plate we did an 8" step on the frame of my 51 shoebox, good god it is strong, and sexy as hell. bless the plasma cutter
My thoughts exactly same as Gambino's. Without getting into a big engineering discussion, the stiffness of the frame rail is provided by the height of the section. By removing more than half of it, even with the extra plate and the tube, it still has much less resistance to bending. There is a reason building floor joists are 2x8 or 2x10 and not 2x4's. Same principle here for the frame rail. The best way would be to add some height ABOVE the frame rail, which could be incorporated into the boxing plate. There should be a small amount of clearance from the bed floor that you could use to add height and not get into cutting out the floor. Good idea on the tube piece though, I will keep that in mind for use myself.
Question for the builders - Alex, 38Chevy454, etc: If he did cut to far and now there is a compromise in the frame at that location, could a thick plate be welded along the top (or sides or both/either?) to prevent localized bending and stiffen the area where a bend would occur during extreme load? Just thinking out loud. Since this is a truck with a bed for hauln' stuff. Loads could be heavy out back. Jon
looks great so far- however, I agree, it needs just a little more work- here's what I would do. Add a new gusset piece over head, and extend the boxing out a little more. You may need to cut out the floor/bed a little, but it will be worth it. Great tech post
The frame rail where its notched is 4" tall, and 2" wide, and the notched out section is just a tick over 2". I wouldn't cut much over half of the original out, cause like Gambino said, anything over half will weaken the rails behind the notch. The pictures are a little deceiving since my digital camera is a POS. That driveline tubing is .187 wall, and made outa some strong shit, I've done 'em like this for years and never had a frame bend or crack.
The answer is yes. That is usually reffered to as a step-notch because it looks like the frame was stepped up and over the rear axle. Here are a couple examples This one is one piece and slides down over the frame rail and gets welded on before you cut the rails out and weld in pletes to complete the job This one is the basic 8 piece (4 pieces per side) that is a lot more welding. This one is actually a "bolt in"
were doing a notch on a 67 caddy convertable right now and every thing has to be done under the floor and what were doing is simaler to what buschandbusch's diagram looks like. were actly doing it a bit of over kill but it be beter than buckling quater panels.
Just as buschandbusch diagrammed is what I was talking about. As to the question could you add extra thickness to the side plates, while not increasing the height? Sure that would help, but the real benefit is from the height, not the thickness. If you had no option, then thick boxing and reinforcement plates would be better than thin. As Gambino said, overkill is a good thing when dealing with frame modifications. That also means GOOD welds, not pigeon shit welds with no penetration.
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