I had been avoiding making the VS-16 spacer for the top of the rudder of my Bede BD-4C airplane for weeks. Everything else that I have made to date has been out of aluminum. This was the first part made out of 4130 alloy steel. I knew that this was a very hard steel and worried that I would have difficulty cutting the part from the sheet and drilling the holes in it.
My first idea was to buy a metal cutting blade for my band saw. I found a supplier, paid a nutty amount of money for the blade, and never could get comfortable with the idea of actually using my woodworking band saw to cut steel. Being a woodworking saw, it runs the blade at 2,960 fpm but I have read that the blade should run at about 240 fpm for 4130 steel. I did find a write-up on the internet of a technique for cutting 4130 steel on such a saw but it involves pushing the material hard against the blade. Since the VS-16 spacer is only about four inches long and less than an inch wide, I could not think of a way to do that safely without getting my fingers uncomfortably near the blade.
In the end, I decided that the band saw was simply the wrong tool for the job. I bought a pneumatic cut-off tool with a 3″ disc and that made short work of the cutting. It was a little tricky using a cut-off wheel to make a long-ish slot in a sheet of steel. I kept getting the wheel just slightly sideways in the slot, which would jam the wheel and stop its rotation completely. I did get through it, though, and was much happier to have the sheet of steel clamped to my workbench and all ten of my fingers safely away from the business end of the cut-off tool.
My next worry was drilling the holes for the bolts and the rivets to hold the nut plates. I had read horror stories on the internet about people who “work hardened” 4130 steel trying to drill it. Once hardened, it becomes virtually impossible to drill and turns into a great device for dulling expensive drill bits.
The internet was my savior, once again, with words to be read and even videos on YouTube. I set my drill press for its slowest speed, put a couple drops of 3-in-1 oil on the spot to be drilled, and applied a fair amount of pressure to the bit. I do have pretty good TiN plated drill bits and they cut through the steel like butter. It was very satisfying to realize the the job was much easier than I had feared and that my inexperience had blown the whole thing way out of proportion.
When I had all six holes drilled, I used the Scotch-Brite wheel on buff the VS-16 up and make it look all purdy. Once I paint it, you won’t be able to tell, but it sure looks nice today.
I have been working my way from the control sticks back to the tail of the plane, making the brackets to hold the control systems. With the VS-16 out of the way (it was a hold-over from when I made the rudder in December), I returned to making brackets and fabricated two brackets out of 2″x2″x.063″ aluminum angle and four brackets of of a flat sheet of .063″ aluminum.
Next up: woodwork, believe it or not. There are hardwood spacers which go between the two CS-26 brackets and between the two CS-27 brackets.
