Carriage Lock
The mini lathe carriage does not have much weight, so facing operations can cause it to move. I also like to lock the carriage for parting. It may not be necessary, but I feel it is good measure to avoid have the tool bind in the groove. Previously, I would engage the half nuts on the leadscrew (not driven by the spindle). There is at least 0.005" of play in the leadscrew and you are limited to certain spots where the half nuts engage due to the threads, so this wasn't an ideal situation. Once the carriage was locked to the leadscrew, I had to use the compound to set the final position. I made a simple, clamping carriage lock to fix this. Actually, I made two. The first one was mounted with the 2 follower rest screws and had a clamping plate in the middle of the ways. This locked up nicely, but it limited the carriage travel toward the chuck. The 4 jaw chuck that I use most of the time projects far enough from the headstock so this wasn't a problem, but if I have the faceplate or the ER-32 collet chuck mounted, I can't move the carriage close enough. I redesigned the part to clamp only on the front of the ways.
This is a very simple design and didn't take much time to make. I roughed out some 1/4" steel plate with a bandsaw, belt sanded the large faces and milled the edges smooth and square. I milled an 1/8" notch on the clamping foot which fits around a piece of 1/8" drill rod pressed into the vertical plate. This keeps the foot from swiveling when the clamping screw is tightened down. The clamping foot pivots on the vertical plate and the opposite edge is drawn up to the bottom of the bed. I located the clamping screw as close to the bed as possible without rubbing for the most force. This carriage lock mounts to the follower rest screw hole closest to the operator. I thought about making the clamping screw with an integrated lever, but I decided to stay with the cap head screw since it gives me the most clearance for the chuck or work piece to swing over it. I belt sanded the top of the mounting screw and the vertical plate screw, so the clamping screw is the only one with a black top for easy sight acquisition.
Click the pictures below for larger images.
This is a very simple design and didn't take much time to make. I roughed out some 1/4" steel plate with a bandsaw, belt sanded the large faces and milled the edges smooth and square. I milled an 1/8" notch on the clamping foot which fits around a piece of 1/8" drill rod pressed into the vertical plate. This keeps the foot from swiveling when the clamping screw is tightened down. The clamping foot pivots on the vertical plate and the opposite edge is drawn up to the bottom of the bed. I located the clamping screw as close to the bed as possible without rubbing for the most force. This carriage lock mounts to the follower rest screw hole closest to the operator. I thought about making the clamping screw with an integrated lever, but I decided to stay with the cap head screw since it gives me the most clearance for the chuck or work piece to swing over it. I belt sanded the top of the mounting screw and the vertical plate screw, so the clamping screw is the only one with a black top for easy sight acquisition.
Click the pictures below for larger images.