Repairing a Broken Crossfeed Screw
#5
A guy on another forum suggested using a carbide tooth from a saw blade to make a one-tooth cutter, since I only needed it for one cut. I remembered that I had a trashed blade with a narrow kerf in the van. Turns out that it was exactly the right size - 1/16" wide. I cut a tooth off the blade, leaving plenty of metal on it for ease of handling.
   

Another chunk of 1/2" CRS made up the shaft of the cutter. I tapered it down to just under 1/4" diameter and cut a slot half-way through on the vertical bandsaw. A bit of fiddling made the slot wide enough to take the 'body' of the tooth. The carbide tooth was too wide to fit into the slot far enough to give me the 3/16"radius I needed, so a 1/16" endmill was used to cut a pocket for that. Thin tools make me nervous, but it worked easily.
   

The next task was to silver-solder the tooth into the shaft. The over-sized tooth body made it a lot easier. I didn't want the heat required to braze the cutter. That might have caused the carbide tooth to come loose from the body metal.
   

After that, the excess metal was cut and ground away, leaving a strong tooth with good clearance.
   

After carefully aligning (eyeballing) the centre line of the shaft, I fed the cutter into the steel. It cut like a comment from your ex. After the shaft of the cutter touched the body of the crossfeed screw, I measured the length of the slot and compared it to the one on the piece that had broken off. Perfect match. Here's the tiny Woodruff key in the new slot. For reference, the largest diameter seen here on the shaft is 3/8".
   

After cleaning up the tool marks (read vice-grip jaws - I did mention brute strength and ignorance) on the bearing body, I put it all back together. It all runs smoothly.
   

It's a long trip from feeling sick after the lathe toppled off the dolly and I saw the damage that was done. I feel a whole lot better now.
Mike

If you can't get one, make one.

Hawkeye, proud to be a member of MetalworkingFun Forum since Jan 2013.
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Messages In This Thread
Repairing a Broken Crossfeed Screw - by Hawkeye - 11-27-2015, 11:56 PM
RE: Repairing a Broken Crossfeed Screw - by DaveH - 11-28-2015, 09:23 AM
RE: Repairing a Broken Crossfeed Screw - by Hawkeye - 11-29-2015, 09:43 PM



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