difficult faceplates

[David Eppler]

I was doing some turning over the weekend trying out a new faceplate. The faceplate went on quite easily - no cross threading. While turning I had a catch that managed to stop the spinning (just got a Powermatic 3520A a couple of weeks ago - gloat). I assume the belts slipped when the piece stopped turning.

Anyway, it was VERY difficult to remove the faceplate - not the initial move that is solved with the nylon washer but rather it was a fight the entire length of the threads. I then tried putting my oneway and Nova chuck on and they were difficult to get on but did eventually seat. Those 2 chucks now go on/off like normal. However, NONE of my faceplates (nor my wood river chuck) are going on far enough to seat. They seem so just stop threading on with about 2 or 3 threads left.

Is it possible I damaged the threads (would expect the spindle to be harder than the faceplate though)? Was the catch and this difficulty just coincidence? This was the first time I had used a faceplate on this new lathe.

Any theories why the 2 chucks are now working well but not the faceplates/wood river chuck?

Any ideas what I could have done, how to check and possible fixes?

Thanks,
David

[Jim Burr]

Glad you wern't hurt David!!! What is the faceplate material, aluminum or cast iron/steel?

[Tom Winship]

David, did the new faceplate have a set screw in it? It could be possible that if it did, and this was the first time the faceplate was used, The set screw could have damaged the top of the threads (barely touching the crests)
Regardless, I would think the threads have to be damaged for none of the other components to screw back on. If the lathe stopped, the belt was slipping which is a good thing. If thread damage is enough to cause the problem you are having, I would think you could see it.

[Steve Schlumpf]

Tom brings up a valid point about set screws. Check and make sure that the set screw isn't protruding past the threads within the faceplate. That would really make things hard to thread back onto the spindle.

[David Eppler]

Thanks. I really should not have been turning. I had spent over 8 hours in the shop on Saturday but I had an idea for a camphor platter with a bowling ball piece as an inlay that I was chomping at the bit to try. The camphor had some beautiful red to it and the bowling ball red looks like a burl ( kind of). Will post pictures once I have oil on the piece.

The first faceplate was the aluminum one from easy wood tools. The other faceplate that will not thread on is the one that came wih the lathe.

[Faust M. Ruggiero]

When your 3520 showed up from PW, assuming you bought it new, it came with a 3" faceplate installed. There are two set screws on that face plate and both would have been tightened. We must assume you loosened both screws when you originally removed the faceplate or you would have damaged the threads then. However, damaged threads are easily seen with a quick look. If they are damaged, just touch them up with a triangle file.

[David Eppler]

Thanks guys. I will look for a damaged thread around where the face plate stops and hit that area with a triangular file.

I bought it used a couple of weeks ago but it is the 3" face plate (both the EWT and the Powermatic original) that refuse to screw on entirely. I have the set screws taken out completely right now but perhaps one was dangling down onto the threads just slightly - damaging the tops of the threads when I first removed it yesterday.

The baffling part to me is why the chucks are screwing on nicely and why the face plates just suddenly stop with about 2 of the threads still showing. The face plates start just fine - they just refuse to finish screwing onto the spindle. Guess the chucks may have more slop in their adapters (Oneway and Nova) than the face plates?

I will look more closely tonight at the threads for damage around where the face plates stop screwing on. I had tried to use the wrench that came with the lathe to tighten the original face plate (thinking that it could straighten any damaged threads) but I literally can not budge the wrench.

[Tim Rinehart]

One possible explanation for the chucks going on more easily is that a lot of chucks are made with RH/LH threads for outboard mounting (I think that's the reason) which ends up giving the threads a bit more wiggle room. I know my Stronghold is like that. As for hardness of spindle...I wish it were harder than it is, they are quite easily damaged, but not terribly expensive to replace. I think about 150 bucks or so.

[Jerry Marcantel]

I rarely use a face plate even though I have 3 of them. Two are Delta 6"ers, each with the right/left hand threads. I've notice that on one of them, the spindle protrudes past the faceplate 1/16"+ when I do use it. Ive compensated by either drilling out the bottom of whatever I'm going to turn, or use an 1/8" washer between the FP and spindle bolt that I had made for another purpose.... The third face plate is a 3" something that's aluminum, and it's hard to get screwed on, and harder to take off. I don't use it at all.
Why don't you make a chuck plate and use that instead of a face plate. That way, you won't need to remove your chuck............ Jerry (in Tucson)

[David Eppler]

Thanks everyone. A few minutes with the file and everything was back to normal. I must have left the set screw down just a bit and damaged the threads. Had I not been too tired I probably would have stopped and checked the set screw when I first met resistance taking the face plate off.

[robert baccus]

Thanks everyone. A few minutes with the file and everything was back to normal. I must have left the set screw down just a bit and damaged the threads. Had I not been too tired I probably would have stopped and checked the set screw when I first met resistance taking the face plate off.

This bring to mind a favorite subject of mine. when we use a plastic washer to prevent binds we miss the boat think. i use machinest anti-bind and lube. heavy stuff with fiber and powdered metal and grease. every auto parts store has it for 3 bucks. prevents galling and wear and binding. 4 to 6 times a year with the brush and through. next time in a machine shop look around.