locjaw does his homework! (mind if I copy?) U.H.M.W. is exactly what I'm talkin about! My rig is low budget tho, I wonder if there's a source for this stuff used? Recycling yards maybe. Speaking of recycling, what's that other slick plastic stuff called that is made from recycled plastic, looks something like plastic O.S.B., comes in all colors and sizes.... they have it at my plant on the tables to slide fresh machined parts on. I don't mean the recycled plastic they make deck boards out of, inflexible and they break ( been there,screw that)!

it does work real well, i like the 3/8" teflon i work at an aerospace manufacturer plant and have acces to stainless, aluminum, titanium, teflon, heat treated, tempered.....
im going with the teflon if you went off a jump and landed right on it it may get bashed through but so would steel, basicly if your bolts will hold it will too, the only down side is its so slick you cant control your slide im told aluminum is so soft it digs in and does not slide most popular is .120 mild steel (about 1/8 inch)

Well, 1/8 inch steel sheets I got, and that was the original plan. I have a 2wd tracker frame that I wanna SAS and take a little more time ( therefore more money) to build. I'm gathering up parts and materials and some feedback on lightweight plastic's durability would interest me. Anyone else? I've seen it on the bottom of some competitive rock crawlers (in vids).

U.H.M.W. is exactly what I'm talkin about!

That stuff is way too expensive for this purpose.
I'd personally use 1/8" plate, or the next size down. It's not that heavy that it would sag the front end Besides, what's wrong with weight anyway? I'm trying to add weight to mine!

Yeah, and it's weight down low, a good thing, right? My son is building a semi mild VW baja (go to my flickr site in my profile) and I just helped him lay out a simple pan that covers his engine and transaxle. The 1/8 inch steel stuff is easy to work with and I picked a bunch of it up at the scrap yard. Our main prob is how to fasten it on and not leaving big bolts hanging down that we're gonna knock off or damage enough to make removal difficult. If you take a close look at the trans crossmember you can see how they've designed recessed bolt holes. these are stamped metal tho, ours we'd have to fab. I was just thinking (uh-oh!) about maybe building up the steel around the bolt holes with thick washers welded on or maybe welding or bending vertical tabs to bolt to the side of the frame. Ideas anyone?

I used cap head screws, the type that have the rounded edges. I've replaced them once because they were getting a bit worn down. You could also use the countersunk type with the special cup washers. You could also make a large round hole with a couple of plates welded behind it to sink a nut.

prolly the best is to bend the plate up on four corners with tabs tapped into the side of the frame, thats the other reason im using the plastic 3\8 thick gives good counter sink room without much loss in strenth my flat head bolt will be recessed 1\8 inch into the plastic surface

   This is how my son Steven bends 1/8 inch sheetmetal!

His idea to protect hi fasteners. Think this'll work on the rocks?   

great idea!!!

So, U.H.M.W is available |removethispart|@ steel & counter-top places? Any other sources? What do you use to work with it? Saws & regular drill / step down bits? How do you bend it / bond it? Or, are you stuck only using it in flat sheets?

yeah pretty much flat sheets work best ive seen someone notch a "v" out of the back side allowing an angle but it tore apart after about a year maybe too much notch maybe bad idea, use regular tools but it is way messy you will have shavings everywhere all over your tools

So, U.H.M.W is available |removethispart|@ steel & counter-top places? Any other sources? What do you use to work with it? Saws & regular drill / step down bits? How do you bend it / bond it? Or, are you stuck only using it in flat sheets?

Typically plastic supply shops, not steel shops. Have a look in your phonebook under "plastic" Basic woodworking tools work very well. As far as I've been told you cannot glue any UHMW or HDPE. Bending is tricky, you need to heat it where you want it to bend.

I still think 1/8" steel plate would be a better option. UHMW and even HDPE are real expensive, but I guess it depends where you live. For me it would probably be around $60 for the same coverage as $15 worth of 1/8" steel. I can buy an old oil tank for $25 that I could cut up and wrap the whole bottom

Slightly off topic, but not really. Last night I was using the 1/8 stuff inside the fender wells, odd shaped area with multiple bends and the stuff was really pliable. Bent right in, easy to work. This is the stuff for me! When I button up the bottom, I think I'll use this with 1 inch square stock over long spans for more support. Use son Steve's fastener protection technique, and READY TO ROCK!!! (but not roll)