How To Build Seat Brackets
This is a step-by-step guide to how I made seat brackets for my racing seats. I would like to give a big thanks to Shifted. I basically followed his guide when making these. I figured I would post up this guide for additional information/pictures for anyone interested in making these. You can view his how to here –
This guide is written to the best of my knowledge. If any of my information is incorrect, please feel free to correct me or offer your opinion.
Follow these instructions at your own risk. These seat brackets are not street legal. This guide is for informational use only. You are responsible for anything you do with this information. And please make sure that if you decide to make brackets that you are using quality parts and you spend time to ensure that they are safe.
II. General Overview
When purchasing aftermarket seats, often times they do not come with seat brackets. The brackets are the pieces that go between your seat and your car and hold the two together.
III. Tools and Materials
The good thing about this project is that you do not really need that many tools. If you have some of these tools, this should be a relatively cheap project. If not, you will need to spend a little bit extra to purchase them. Your list of tools/materials may be slightly different, but this should give you a starting point.
Materials - (Per Bracket)
- (2) 36” long ¼” thick flat bar weldable steel
- (1) 36” long 1” thick square stock steel
- (12) Grade 8 2" 5/16ths bolts (you might use different lengths)
- (12-24) 5/16ths flat washers
- (12) 5/16ths locking nuts
- Safety Glasses
- Titanium Drill Bits (Pilot Point)
- High Speed Steel Hacksaw Blades
- Socket Wrench
- Tape Measure
(2) 36” long ¼” thick flat bar weldable steel
All of my supplies were purchased at Home Depot, but any hardware type store should have most of these items. You will need two of these flat bars. They cost me $4.96 a piece.
36” long 1” thick square stock steel
You will need one of these. It cost me $9.98. I used the one without holes, but Shifted used the one with holes. It might save you some drilling if you get the one with holes.
Grade 8 2" 5/16ths bolts
These will be used for connecting all of the pieces of the seat bracket. Make sure they are Grade 8, since other bolts do not have the same strength. These were about .24 cent a piece. You may use some different lengths depending in your materials and your build.
5/16ths flat washers
I would suggest using these. They cost me .19 cents a piece. Thye help distribute the pressure of the nut and secure it.
5/16th locking nuts
These obviously go on the bolt to secure the pieces of steel together. They were .29 cents a piece.
Never forget about safety. When you are drilling, pieces of sharp metal may fly around. It would not feel very good in your eyes. Spend a few dollarsa and get some safety glasses.
If you do not own a drill, you might wanna think about buying one. You will use it on almost any project you do. They have drills in all prices, depending on features and quality.
Titanium Drill Bits (Pilot Point)
These will be used to drill holes in the metal. If you wanted, you could just buy a single 5/16” bit. I purchased a small set for $20.
This will be used to cut the steel. I purchased the on below for $20, but they have them as cheap as $5.
High Speed Steel Hacksaw Blades
Make sure you get the correct blades. You want high speed steel blades, but if you can’t find those look for quality blades that are made to but through steel.
Just like the drill, I suggest investing in a socket set. You will use them a lot. You can get a small set for pretty cheap, and pick up other ones as you need them. I just bought a big set.
These range from $5-$30. You don’t need anything fancy, just something to measure under a few feet.
Clamps range from less than a dollar to several dollars a piece depending on size. These will come in handy to hold the bracket in place.
You can either buy a set or make your own. I made a pair of sawhorses out of a couple of 2x4 boards. It is very helpful when cutting/drilling.
IV. Removing Your Seats
To remove your stock seats, you will need either a ½”or 13mm socket. There are 4 bolts holding each seat in, one in each corner. Simple remove them. Your passenger side seatbelt is connected to the floor, but the driver side is connected to the seat. You will need to remove it and attach it you your bracket you are making if you still want to use your stock seatbelts(do not mind the messy carpet, it is being replaced).
V. Cutting the Initial Bars
You should have 2 flat bars and 1 square bar for each bracket. For this step you will need one of the flat bars.
We will be cutting/drilling the 2 crossbars out of this piece. Measure the distance between the two rear bolts. You will want to add some onto this measurement so that you do drill the holes for the bolts right at the edge.
Now that you have the measurement, measure and mark the steel bar. Then cut the bar with the hacksaw. It may take a few minutes, but it will cut through.
Once you have your piece cut, put it over the bolts. Mark the spots where you will need to drill holes for the bolts. I recommend starting out with a small drill bit and working your way up to the size hole you need. I find it easier this way.
Once you have one side cut, place the bar on the bolt and make sure you measurement for the second home is still accurate, then drill the 2nd hole.
Once you are done with the rear crossbar, repeat these steps for the front one. When you are done, you should have the picture below.
VI. Cutting the Support Bars
For this step you will use the tube stock. Measure from the front crossbar to the back. This is the length you will need to cut the tube stock. I cut mine slightly longer, but you should be able to cut it flush with the edges of the crossbars.
You want to place the support bars as far apart as you can, but you want to make sure that you can still screw the nut onto the 4 bolts sticking out of the floor. The front bar is shorter than the back one, so find you spot to mount the support bar on the front crossbar, then run the support bar straight back. Remember, there will be a seat on top of this when you are installing them, and it will not be as easy to install the bolt. I placed a washer on the bolt from the floor, and left an extra 3/8th inch from that.
Once you have your measurement, cut the tube stock. Follow the same process of placing the tubes tock on the crossbars and marking your holes as you did in the last step. Once you mark your hole, drill one and place it back on the bolt to make sure your second hole still lines up.
You will need to cut a hole in the crossbars directly under these holes in your support bars, so that you can run a bolt up from the bottom. The place a washer on top and tighten the nut down with your wrench. Your finished product should look similar to this.
VII. Cutting the bars to bolt to the seat
You now have the base of your seat bracket. If you look at the bottom of your seat, it should look similar to this (these seats have sliders). The sliders run in the same direction that your support bars run. So we will need to take your 2nd piece of flat steel and create the bars that will connect your bracket with the seat.
As before, you will measure the distance across the seat. Measure this same distance on your flatbar and cut. Take the piece you cut and place it under the seat, and mark where you will need to drill. Drill these holes out, and run a bolt through each side.
Once you are done, your seat should look like below (Note: The bars should be parallel. Mine do not look it in this picture since the sliders are at different levels.)
VIII. Attaching the Bracket and Seat
This is the fun part. You must now attach the bracket and seat. The reason this is “fun” is because you have to set the seat on the bracket in the car, make sure it is aligned how you want it, and mark the places to drill. Be patient with this step, and make sure everything is lined up. Otherwise, you will drill and connect these pieces and they either won’t line up, or your seat will be crooked or it might not fit. If you have sliders, make sure that the seat can slide without hitting anything.
I found the easiest way to do this is to set the seat in the car and adjust it to how you think you want it. Then put a clamp on each corner. Once they are clamped in, you can check the fitment and stuff a little easier without moving the seat. Once you have the seat positioned correctly, carefully remove the seat and undo the bolts on the bars that are connected to the seat, so the bracket is all one piece. (In the picture below you see I have one side done and am working the on the second side.)
To ensure that everything was lined up, I left the clamps on and drilled the holes (I just moved them out towards the edge more. You will drill through both the flat bar and the tube stock, and run a bolt up from the bottom again.
Repeat for the other side, and you should have something like this.
Now, bolt the bracket back onto the seat. You already have the holes, since you drilled them in an earlier step.
IX. Installing the Seat
All you need to do is place the seat back into the car and put the bolts from the floor through the holes in your crossbars. Hopefully if you were careful with your measuring everything should line up. If not, you will have to figure out where the problem is and redo that part.
I had other seat brackets on the seats when I bought them (used off an org member). These brackets sit a little lower then the ones that the other guy made, since as you will see he used all tube stock and no flat bar. If you do not want your seats lower, you could use all tube stock.
X. Old vs. New
Some of you may ask why I went through all of the trouble of making new seat brackets if I already had some. The main reason was safety. Whoever made the original brackets did not do a very good job. None of the bars were straight, some of them were to close so you couldn’t screw the nut onto the bolt, ect. Why don’t I let the pictures do the talking.
I hope this tutorial was helpful. Once again I would like to thank Shifted for his tutorial. If you have any comments/questions, feel free to contact me.
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