Many router tables and other pieces of fixed workshop equipment have a t-tack or t-slot in the table into which you can fit a t-nut. The t-nut is used to hold down other pieces of equipment such as feather boards and various jigs. In this Instructable I make some t-nuts for the t-track I fitted in my router table.

Let me first say that I don’t know whether this project should necessarily inspire you or act as a warning. Nothing went wrong and the end product is great but it was hard work because I only have woodworking tools. What this project shows is that with a little determination and some lateral thinking woodworkers can do some metalwork.

This project along with loads of others is also available on Wobblycogs Workshop.

Materials

10mm aluminium sheet. Grade doesn't matter. Size depends on how many t-nuts you want to make.

Tools

The tools list below are what I used. You could complete this project a lot more easily with a milling machine.

Mitre saw
Chisel
Files - needle files were the most useful
Belt sander
Sand paper
Drill
M5 Tap

Step 1: Cut the T-Nut Blank

The first thing you need to do is cut a long blank of t-nuts. It's much easier to make a row that will be cut up later than to try and make one at a time.

Lubricate the aluminium thoroughly before each cut and then square up the edge of the aluminium. Cut a shoulder along the squared up edge, this creates one side of the T shape. Move the material across in the saw the width of the top opening of the t-track and cut another shoulder. Move the material across again and cut the t-nut blank free at the width of the bottom of the t-track.

When cutting the blank free don't cut all the way to the end as there's a danger the blank will go flying, instead clamp the material to the workbench and use a hacksaw to finish the cut. You now have a very long t-nut.

Step 2: Test Fit and Clean Up the Shoulder

Test fit the t-nut blank in the t-track. I found that the width was good but the height of the shoulders was a bit off - they were slightly too tall.

When trench cutting on the mitre saw the saw is unable to cut right to the fence and this leaves a small amount of material on the shoulder at one end. I initially tried to clean this up with my large blunt file but after five minutes of working hard and achieving nothing I switched to plan B. Plan B was to use one of my old but sharp chisels to chisel the waste away, surprisingly this worked very well. Once I'd removed most of the waste I used a small file to clean up the shoulders.

Step 3: Reduce to Thickness and Clean Up

As mentioned earlier the shoulders were a little too tall to got into the t-track and the easiest way to reduce them was to reduce the thickness of the whole blank by sanding the bottom of the t-nut (e.g. so the nut sat deeper in the track). This was easily done using a belt sander with an 80 grit belt. The edges of the t-nut blank were too delicate to be finished with the belt sander so I quickly made a lap and lapped the edges taking care to knock off any sharp corners. Sand until the whole blank will fit into the track.

Step 4: Divide Up and Clean Up

Divide the t-nut blank up into reasonable sized nuts. I found the width of my steel ruler (about 25mm) was a good size and it gave me eight nuts which should be enough to keep me going for a while. Use a hacksaw to cut the blank into pieces and then clean up the cut edges on the lap.

You could try cleaning up the cut edges on the belt sander but I found the pieces hard to hold onto because they are small and they heat up quickly.

Step 5: Mark, Drill and Tap

Find the centre of the t-nuts by drawing a line from corner to corner and then drill and tap them. I found that M5 was a good thread size for these nuts as it gave a reasonable number of threads in the nut. If you required a larger bolt I think M6 would also work well.