Probably one of my favorite things to do when building classic trucks is making brackets. They are needed all over the car or truck you're building. Master cylinders and boosters hang from brackets. Throttle cables and such need brackets - brackets for tanks, shields, coolers, etc. The list goes on. They need to be strong enough to handle their job. They should also look good, like they belong there. This comes down to planning. All my brackets are planned out on cardstock first.
It took me a while to figure out how to make and use cardstock templates properly. But once I got it, it's the only way I make anything from scratch anymore. Cardstock is cheap; mistakes and design changes can and should be made here, not when you are working with the material. I lay out everything I need on the template: hole locations, lightening holes, if used, and any notes I need like drill or tap sizes and such.
Follow along as I create a Panhard bar bracket for a rearend housing from a cardstock template and a couple of dimensions.
First I need to know some measurements to build the template to. I start by measuring the diameter of the rearend housing tube the bracket will be welded to. This will give me the radius for the bottom of the bracket. Looking down from above, I hold a bar in place so I can visualize how it's going to be positioned when done. I want the bar to run parallel to the rearend housing so I measure from the front of the housing to the backside of the bushing on the end of the bar and the tape measure says its 4 inches. So now I know that I need the forward part of my bracket 4 inches forward of the axle tube's front face.
How high it will sit above the housing is the next dimension I need so I measure up from the top of the housing to the center of the bushing on the end of the bar. This time I'm looking at 2 inches. Since ultimately the bar needs to be parallel to the ground, another way to find this would have been to measure from the mount that is already on the frame for the Panhard bar to the ground. Then from the top of the housing to the ground and the bracket height would be the difference. This would work here because I have the chassis suspension sitting at ride height on the jackstands.
Ideally what we are looking for here is a bar that mounts to the rearend and to the chassis. This bar keeps the rearend housing centered in the chassis under side loads. Since it's a bar it will travel through an arc as the suspension travels up and down. The longer the bar, the less arc or deflection (side to side) of the rearend as it travels.
This truck started with a 15-inch bar that was frame mounted and then mounted to a bracket on the front of the third member at the pinion. By moving the mount to the far passenger side of the rearend, I increased the length by 10 1/2 inches. Although when I moved the bar's mounting point up on the new bracket I did also raise the roll center a bit. The rear of the truck is sway barred and it will never be road raced so I'm not too worried about the change.
Now that I know some dimensions, I can start laying out the bracket I need on some cardstock. The cardstock or poster board I use comes from the local Target; I use a lot of it and buy it in bulk packs. Almost every bracket I make will start on cardstock. If the bracket needs any bends, those are replicated with a piece of welding wire. The bracket is made from the cardstock template, then bent to the wire template.
I start with a vertical centerline, then draw in the diameter of the rear axle tube with my circle gauge; in this case it was 3 1/4 inches. Next I measure up 2 inches for the bracket height and make a line, then I measure forward of the front edge of the circle 4 inches for the length of the bracket. I'm going to make the front mounting face of the bracket 11/2x11/2-inch square so I'll make the end of my bracket 11/2 inches wide.
The bracket at the other end should take up about a quarter of the tube diameter so I eyeball in the distance and make marks. Connecting each end of the bracket to form the bracket is a matter of taste. I like swoopy, flowing designs, but it could also be done in a squared boxy style.
When I'm happy with my drawing I cut it out and give it a check fit. This way can see if I'm even in the ballpark. If all is good, I move on to the steel. Follow along with the pictures and captions as I make up a simple bracket with some design to it.
01 Cool-looking brackets are just a cardstock template away. Follow along as I start from some measurements and a piece of cardstock to come up with this new Panhard bar mount.
02 It all starts with a centerline. On a piece of cardstock I measure in an equal distance from the edge and make a line. In this case it will be the vertical centerline of the rear axle housing.
03 These rear axle tubes are 3 1/4-inches in diameter, so I find the 3 1/4-inch circle on my template and line it up with the vertical centerline I drew. I draw in the circle and also use the template's centerline gauge to mark the horizontal centerline, then I draw it in also.
04 I did some measuring and checking before I started and found that I need the attachment point centerline for the Panhard bar 2 inches above the top of the rearend housing. So I measure up 2 inches from the top of my 3 1/4-inch drawn circle and draw in that new centerline.
05 I also knew the mounting point needed to be 4 inches forward of the housing. So this time I measure from the front of the drawn circle, make a mark, and draw in the line. Now I have lines showing my limits.
06 I'm going to make the forward attachment piece 11/2x11/2-inch square with a 9/16-inch hole for the bolt. This is where the bushing on the end of the bar will bolt to. This being known, I divide the 1 1/2-inch half and make marks from the 3/4-inch centerline. This is how the width of the top end of my bracket is decided. The bracket's base width on the housing will be eyeballed in. You want about a quarter wrap of the bracket around the housing tube.
07, 08 Then it's just a matter of drawing in something that looks nice and flowing, or you could stay with a boxier style with straight lines. Here's where you decide and make your mistakes with the cardstock. If you cut it out and don't like it, you can easily start over. Since this is kind of a race truck theme, I like putting lightening holes in the brackets. Old racing trick and it looks cool. My smaller circle template works great for this. I decided on a 2-inch and two 11/8-inch holes on these side brackets.