Problem with lathe -need help

[Mikey]

I have a Delta Midi lathe that is roughly 3 years old. When I first got it, I didn't use it much, but did make a few pens. I found then that the mandrel would wobble and produce pens that did not fit flush with the trim parts. I took the lathe to the repair center and they replaced both bearings in the headstock as well as the top pulley, the belt, and the spindle. It seemed fine until just a while ago. It started wobbling again, but I was able to spin the mandrel, or move the bushings and it would seem to calm down again, possibly because I shut it off. (no clue actually) Within the last week, just about every bushing I put on the lathe will wobble some, with some being worse than others. I suspected a bent mandrel, but I have tried 3 different ones so far from different companies all with the same result. Today, i took the entire thing apart twice and cleaned it. The first time I just cleaned the lathe, but the second time I tried switching some of the old parts to see what would happen. (the guys were kind enough to give me the old stuff they took out in case I needed them later.) Anyway, it still wobbles and keeps getting worse, no matter what I try.

I imagine the only thing it could be is the shaft with the morse taper, but I am unsure. Has anyone else had this problem, or does anyone have any clues as to what could be happening? The only thing I haven't tried is buying one of the MT#2 cleaning sticks and shoving it into the lathe.

I wish buying a new full size lathe was an option, but I must make this one work for me for a while longer.

 

[johnson]

Try cleaning the inside of the morse taper. It is kind of like cleaning your ears, you will be surprised at what comes out. Also, check the angle on your cone tail. It needs to be 60 degrees to match the end of the mandrel. If you have access to a dial indicator, check for run-out on the spindle at the headstock. Also check for head and tail stock alignment. If it is off, you get wobble.
Dale

 

[Mikey]

Thanks. I know that when I insert the mandrel into the headstock and turn it by hand, the shaft wobbles quite a bit as I can see it by eye. If anything, the tailstock calms down the wobble. I will try to see if I can clean out anything.

 

[btboone]

The same goes for the shaft that plugs into the taper. If it has any dings, it needs to be sanded down to flush.

 

[woodwish]

Clean your headstock, and you don't realy need anything special. I use a rag and lacquer thinner. Just keep stuffing and twisting and poking with something long and thin. Keep doing it until it comes out clean. You will be amazed what all comes out of there. Resist the temptation to turn on the lathe as you stuff in the rag (no, I didn't do that but I know someone who did). It may not fix the problem but won't hurt, plus gives you something to do while worrying about the problem!