What I want to do is take ~8” long pieces of 3/8” to 1/2” diameter aluminum rod and taper the last 2” down into almost a point.
What I do have is a 10” drill press. What I don’t have is a mini lathe.
I could use a bench grinder to taper them down, but I don’t think I could do it uniformly without flat spots. Was thinking of possibly attaching a chuck to the table under the drill press chuck and use that to spin up the rod. I could then use a file or grinding stone to taper down the bottom. Once finished, I’d just break off the piece in the chuck. I tried searching online, but all I could find was a chuck for spinning wood.
Just looking for ideas here really on how I can make a uniform taper on small diameter rods.
This is just a Idea, but will require a belt sander. I suppose a file would work but would be painfully slow.
Chuck the rod up in the drill press very firm, mark the 2” all the way around with a sharpie. Use a coarse sanding belt 80 grit or coarser.
Run the drill press as slow as possible. Start sanding at the very bottom edge working the angle without touching the 2” mark. Once the angle is almost to a point at the bottom start working it to the 2” line. Go slow for the finally pass and it might help to switch to a finer sanding belt for the finally pass depending on how fine you want the finish. You need the belt sander or drill press running in the opposite direction of the other for this to work. I think its very doable taking your time and keeping the aluminum rod cool so that it doesn’t gum up your sanding belt.
Thanks for the reply, moderator007. I don’t have a belt sander, but what you say makes sense. I’m not sure why I got it in my head that I needed to chuck both ends. I’ll try that using course grit sandpaper on a block and possibly a file.
Mount the rod in the chuck of your drill press and set the speed at the slowest it will run. Then the side of a sharp hacksaw blade can be held up against the spinning part to quickly remove material. Using just the part of the teeth that sticks out to the side, not the regular full tooth.
Hold the side of the blade against the work and slowly rake it up and down, and back and forth, to clear the chips and present fresh teeth to the work. Mount the blade in the saw such that the teeth are facing back toward the handle, and hold the saw on the left side of the part so that the saw is being pulled away from your body if it happens to grab and pull out of your hands.
Once it is roughed out to the taper you want then hold a coarse file against the work with the same raking action. Rub a piece of chalk across your file first to fill all the grooves with chalk and it won’t get clogged by the aluminum or take too big a bite. Follow up with a smooth file (always chalk your files), then sand paper block, then steel wool or abrasive cloth to get it shiny.
you need to work both sides if the sandpaper\file is stationary, and you have to put lateral pressure, for it to bite into, you risk bending your rod, but with belt sander you do not need to apply much pressure, since moving belt is shaving the rod
i’d make a wood block with a v channel of needed size, line it with sandpaper and “drill into it” slowly. first use coarse grit, and go finer as you get to desired size.
If you have straight rods, you can chuck them in cordless drill /screwdriver, add some bushing with handle near other end for extra support and use bench grinder to remove material. Your grinding wheel will not be in great shape after this, but I think you can get an uniform taper.
If you have a dozen of them to make, it is probably a good idea to make a jig. If you mount a round stock at the angle in V-block (and limit axial movement), you can get a perfect cone shape by rotating rod and forcing any cutter/sander into it.
