The ’47 panel truck bed wood has a strip across the rear that is held on with 10 bolts. From what I have found these bolts are called Countersunk carriage bolts aka 114 deg countersunk square neck bolts aka Flat square neck plow bolts. This is a ¼” bolt maybe ¼-20, and about 1 ¼” long. I’m missing one and another is bent. I have found some on-line that don’t match the dimensions, so I’ll go to the local fastener supply places next. I thought someone here might have a source. Thanks.
I couldn't find them either. From what I have read at other websites, some are using stainless Torx flathead bolts. The reason being, removing the old bolts with the square on the neck simply spin in old wood (no grip). Have to grind the bolt off from the bottom of the bed. If you want the look of original, find someone who is good with a lathe and have at least 10 of them so they look the same.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
These are very similar, but the angle on the head is slightly different.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
If you look closely at the angle under the head, it is closer to a plow bolt.
Looking at picture two, I zoomed the picture to closely match one inch on the scale, then I measured the head size in picture three. You’ll see that the head size is closer to 5/8”.
However, MSC doesn’t carry plow bolts that small (1/4”-20) nor have I found any place on line that does.
I would post an ad in the” Truck Parts Wanted” forum. I’ve had very good luck getting what I need from fellow ‘bolters. Good Luck!
Last edited by Phak1; 07/09/20212:13 PM.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
The 114 degree part may or may not be right, I did see some bolts called 100 degree, I think that's the angle of the countersink. I may be able to use elevator bolts, but I'll keep looking for plow bolts. I also checked on the Grainger website, didn't see any that small. I did find something that might work if I wanted 1,200 of them: https://www.globalindustrial.com/p/...9-avW8QIVQRB9Ch1jegjiEAQYASABEgIvbfD_BwE I'd like to see if it fits before buying especially that quantity. Now I feel like I should take the endcap with me when I go searching. I didn't know there were bolts there they sit flush and just blend in nicely. Today I will go by the local Fastenal and see if they have something: https://www.fastenal.com/products/details/0110615 This is 5/8" long and not a catalog item, may have to have some made? The problem with on-line catalogs is they don't contain some odd bits that you might find in a dusty bin at a retail location.
I don't know what the "strip" is or does. It was not defined and pictured. I always try to search pics on the internet . It may be a trim strip running left to right at the rear end of the wood. I don't know if it is removable or not. I guess these weird bolts hold down the strip. Walter: I believe in this case I would not dwell on finding this bolt. I would do something that would enable a standard bolt. Something available everywhere. A stove bolt, a carriage bolt, a round head bolt. I don't think it NEEDS to be a flat head bolt. I don't believe it NEEDS to have a square shoulder under the head. So I would do one of the following: 1. Take off the strip. 2. Weld up the hole, at least at the top. 3. (A) Drill a thru hole only........ or (B) drill and countersink to match a standard countersink. 4. Use a standard round head carriage bolt. Grind off the corners of the square. 5. Use a standard flathead carriage bolt. Grind off the corners of the square.
No. 3A/4 being my preference.
Some folks here could find brass 1/4 square bar, insert it into the strip's square hole, and then weld around it to eliminate the "114 deg" countersink while maintaining the square hole in the strip. Then use a standard round head carriage bolt or countersink it for a standard flathead carriage bolt.
Those are some good suggestions. Yes it is a trim strip at the rear of the bedwood. None of the bedwood holes are square and this strips bolts do not go through the wood. The ten bolts go through the strip, the end hole on each rub rail, and the lower ledge the wood rests on. I measured the countersink angle on the bolt and it is 114 degrees. I found a countersink hex bolt and it measures at 70 degrees, the head is smaller, but it would work and could be filled in for a smooth finish. I like the way the original bolts blend in. I went by Fastenal, but they don’t have any ¼” plow bolts longer than 5/8” listed and they show no suppliers for them. I tried to search farm implement parts, but those seem to be listed by application. If I knew of a specific piece of equipment that uses these, I could reference it. I just need to find a bolt that looks right when installed. I think I’ll get a flat head carriage bolt and chamfer the edge so it sits flush in the 114 degree countersink. Seems like the easiest solution. I find these bolts are used on garage doors.
I see you have one flat allen-head bolt/screw. It looks like it fits well. You don't like the allen hole of the screw? Fill with solder and paint the top.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
I got some flat head carriage bolts, but the head was smaller than the plow bolt. I finally decided to modify an elevator bolt. With the bolt in the bench drill, I used a file to take the diameter down, and then a grinding stone in a dremel to profile the countersink. I could go a little tighter on the countersink edge, but I am satisfied how it turned out.
