The Stovebolt Site Forums The Parking Lot Big Bolts Wood Flatbed Treatment/Torx Screws

What are you guys using to treat your wood flatbeds. I'm going to be installing 2x6 T&G fir in the next week or so and am wondering about what to treat it with. Should I treat the boards prior to installing?

Has anyone used the Torx self tapping decking screws on an 40's vintage flatbed. I have a hard time believing the self tapping screws are going to tap through that C Channel.

We use these self tapping screws on our trailer floors. http://www.imperialsupplies.com/items.asp?item=0692940 We start out by drilling a 17/64" hole through the wood and the cross member. We then have a bit that drills the wood to 5/16" and countersinks it. This can also be accomplished by drilling a 5/16" hole in the wood and using 1/2" bit to make the countersink. Our cross members are tempered steel and we have been repairing floors for 40 years. I would have fears that the 1/4" decking screws you see at bumper pull trailer dealers are made to screw into cross members that are barely thicker than a beer can. The floor screws I describe can be bought at any dealer that sells semi trailers.

We don't put anything on our floors in our dry vans. On flatbeds, I still like mopping linseed oil on on a hot day.

Ken,

What did they do originally on the factory beds (like that Task Force-era bed I'm working on)? Did they use metal strips like the pickup beds, or did they just put carriage bolts through each board? Or something else??

Thanks,
John

It all depended on the body manufacturer John. Soome did use the steel strips between the boards but most used self tapping screws. Generally they were Phillips head. I've had very good results using 1/4" Torq head screws in crossmembers up to 10ga. and Jr Ibeams. Above that ou'd need something heavier.

I started hauling grain in the 60's and in those days the used bob tails for field trucks. They either dumped into the pit at the elevator or were raised with a hoist. It took over an hour to load 1000 bu of grain, so I saw the floor of a lot of truck floors. A few floors had strips, but most had self tapping screws. I don't think torx came out until the 70's. The ones we used were Phillips. In those days, we used a bit and brace to screw them in. I always found me a big ole boy to push down on the brace to keep pressure on the Phillips head. I prefer 5/16" over 1/4" because I have seen a few 1/4" break during installation. They are so hard, its almost impossible to drill them out and you usually wind up with the hole being too big and then you have a hole in the floor. Once installed, the extra strength isn't needed. In order to remove an old floor, I go to a hole in the wood to start. There is usually a hole or you wouldn't be reflooring it in the first place. I then use an old fashioned grubbing hole and chop between the wood and the crossmember and it will cut the old bolts right off flush with the cross member. Another reason I use 5/16" is that if I happen to hit an old bolt when I drill, there will still be enough there for the threads. The remains of the old bolts are usually soft enough to drill. I don't think carriage bolts through the wood were ever factory. I think that was a country boy fix. I'm not sure if carriage bolts at the end of the boards was factory or if someone put them there during reflooring to give the boards more protection against warping. The use of strips or countersunk bolts was then and is still so that things can be slid across the floor. I use an Isuzu bobtail to transport bottled water on pallets from Costco to my place. The Isuzu is too low for dock height, so they push the pallets in, and when I get to my place, I chain them to the rear and then fork lift them off.