A few months ago I started thinking about this upcoming Spring when I wanted to put fertilizer spikes into the ground around the citrus trees. I had been using a long chisel I have, but it was too narrow and I had to work with it to make the hole wide enough to put the spikes in properly. Yeah, I know you are supposed to just pound those spikes into the ground, but invariably they would shatter and not go very deeply where the roots would most benefit from them. So I needed something else.
So I thought, "Hey, I have a lathe, why not
make something?"
I figured I would buy a 2 ft length of 1.5" diameter rod. That would give me the diameter I wanted, and the length would be handy enough so I wouldn't have to be stooping over so far for too long. I had wanted to use stainless steel as the material, but abandoned that idea when I realized how heavy it would be for these feeble old arms I have. It would wear me out in pretty short order lugging that thing around. So I decided on aluminum instead.
I put a 20 degree point on one end by setting up the lathe to cut a taper, and rounded the edges of the other end with a cutting tool for that purpose. A friend of mine mentioned that the spike might get kind of slippery if it got wet, and having the spike drop and hit my foot might not be all that pleasant. So heck, I had a knurling tool that I had bought for my smaller lathe, so why not use it? Unfortunately, it was too small for that large diameter, so I had to find a bigger one. Ebay had some that were advertised as being with 1/2" shafts, so that would work with the quick change tool post holders I have. Unfortunately, that specified 1/2" shaft they advertised turned out to be width, and not height, so unless I wanted to mount the knurling tool sideways (which was ridiculous) it would not fit my QCTP holders. So I mounted the knurling tool on my milling machine and took off an eighth of an inch from the height so it would fit.
I practiced on some other pieces of rod stock I had here to make sure my knurling efforts wouldn't just ruin that rod I was working on. I did find that using too slow of feed for the carriage made a pretty messy pattern, so the fastest speed seemed to be ideal. Fortunately my lathe has variable settings using control knobs to adjust the carriage speed in relation to the chuck rotation speed. Having to change gears would have been a pain in the neck.
Seems that the accounts I read of having to turn a rod to be a multiple of the diameter of the knurling wheels was not accurate info. Apparently when you crank down on the knurling tool to get the wheels to bite hard into the rod, as the knurling tool moves up the rod via the carriage, the pattern in the wheels just tracks automatically in the knurled pattern already made. Either that or I have been just darn lucky.
I knurled over half of the rod, figuring I wanted to have a good grip on it while pounding it into the ground, and also when I was carrying it with my hand on the center of gravity. It was a pretty long span, but the knurling operation went better than I had hoped it would. Beside, I find just watching something like this to be fascinating. I have watched an untold number of videos on YouTube of people doing things with machinery that most normal people would find stone cold deathly boring.
Then I started thinking about maybe smoothing up the portion of the rod that would actually be inserted into the ground. A smoother surface would make cleaning it up go easier. And I like cleaning up my tools after every use, so.... So I mounted it back into the lathe chuck, using a cardboard tube to protect the knurled portion of the rod, and dragged out the various grits of sanding and polishing paper I had stored away from when I worked on wet sanding the paint surface of the vette a while back. I used WD-40 as a lubricant for the sanding and polishing, which worked out really well. After the 3000 grit polishing step, well, all of a sudden I had something that I was thinking maybe I should mount on my wall instead of my intended purpose of pounding it into the dirt.
Sometimes I guess I don't know when to stop... But heck, if we ever get infested with vampires around here, I guess I could test the theory to see if an aluminum spike through the chest would kill them. It does
LOOK like silver!
