I am thinking about making a set of Pete and Jakes style ladder bars for my Model A. I plan on using .75 od x .188 wall tubing. But, do I use: Alloy steel tube 4130 or DOM Mild Steel tube A513 type 5 Those are two (the only two) choices I found listed at a metal supply site in Washington State. Thanks-
Mild steel,without a doubt. I suspect most 4130 stuff on the street is actually mild steel, it just sounds better. 4130 is for serious racecars and airplanes, and because of the carbon content,needs to be welded under very specific conditions. And it costs a bunch more.
The mild steel will be fine, especially if you are welding at home with a MIG. the 4130 is chrome-moly and should be TIG welded. MIG can cause cracking in the heat affected zone and you don't want your ladder bars falling apart. I would go up to larger 7/8 or 1 inch OD bars though. 3/4 inch seems pretty small and may not look strong enough, even if it can work.
Thanks for the help, would the mild steel be what I would buy at my local metal supply or do I have to specify that is what I want- Whats the decimal equivalent of 7/8?
Mild steel should be readily available,DOM will be more money than ERW but worth it. What size tube does P&J use ?
pete & jakes uses 7/8" OD X .156 wall DOM tubing on their ladder bars....188 wall would be fine too , that's what i use when i make a copy of them the rear of the bars will need to be drilled out and tapped 5/8" - 18 thread for the clevis's the front solid bushing is 1-5/8" OD with an ID of 1-1/4" and is 1-5/16" long. their part number is 1208. you can buy them or make them if you have access to a lathe.i have a supply of them if you want a couple.... the microflex bushing is their part number 1205
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