Lathe Face Plate

[Ulma Doctor]

What do I need a ball pein hammer for, when I already have a 12" Crescent that does the same thing?!

Hint: They're not the same thing.

I have found adjustable wrenches to be more effective hammers than wrenches, the reason i call them crescent hammers.

Since I bought some Bacho adjustable wrenches , my views have changed

 

[benmychree]

Never heard of Bacho wrenches; a link?

 

[Chewy]

I have done without face plates for the last couple of years and have been wanting them. I'm in the process of making two. The dog plate will be about 4 x 8 x 1-1/2 inches and I will turn the D1-4 taper and make homemade locking pins. It needs to be two thickness of 5/8 or 3/4" to get out far enough to work with the dead center.
The real face plate will 12" x 1" 6061 mounted to a Shars back plate. Multiple drilled holes for studs and mounting like a pallet. After it gets assembled, I will use an Oxtool trick. When he mounts it on the lathe, he takes a .010 face cut to true up. He said he has been doing that for years.

 

[rwdenney]

When I got the lathe, 16" SB, the face plate and anything associated with it was missing. I would like to get all the parts together so I'd have the option. But dang, where in the world do you scrounge up parts for a 1962 SBL? Plus, looking at the parts diagram it looks like there is a bushing that goes in the spindle that holds the Morse #3, a thread protector (?) then the face plate...Am I correct?

I am a rookie when it comes to face plates...

Yes, for turning on centers you'll need a faceplate and a spindle adapter for 3mt. You do not need the thread protector--the faceplate will serve that duty (which isn't to protect the threads so much as to give you a way to drive the Morse taper adapter out of the spindle). The thread protector is used with the 5C collet closer, which fits into the spindle in lieu of the 3mt adapter when using collets.

(I still need to find the Morse-taper adapter for the spindle of my South Bend lathe, too, and for me it has also been unobtainium. But I have alternative strategies for turning on centers. One is a center with a 1/2" straight shank that I can mount in a 1/2" 4C collet. That collet closer will stand proud of my faceplate with plenty of clearance, and the faceplate itself will serve as the 4C collet adapter remover. That will probably be the most useful option. I also have a 1-1/2" straight to 2mt adapter that I can chuck up in the 4-jaw and indicate in, though it will stick out of the chuck too much for turning on centers. It will also mount in my weird shop-made collet chuck using a 1-1/2" collet, though without the ability to indicate it in and still too much stick-out. But I'll find a use for it.)

Look for faceplates with a "2-3/8 6tpi" in the search term on ebay. They come up more regularly than you think. There is one on ebay right now that is listed as 2-1/4 by 6, but it's really 2-3/8, and will fit the 16 and later 14-1/2" South Bends. (Earlier 14-1/2's like mine use 2-1/4 6tpi threads.)

The faceplate that people use for turning on centers is only 8" in diameter, and those threaded for South Bend threaded spindles are invariably made from cast iron. That's not big enough for a lot of potential turning operations, but it's fine for turning on centers. My lathe came with one (somewhat damaged but still usable) that is 7-1/2" in diameter. I finally found a big (11") faceplate with the 2-1/4 6tpi threads my 14-1/2 uses, but I searched for a while before it popped up and it wasn't cheap.

But if you can find an 7-8" faceplate, you can use it as an adapter for whatever fixture plate you can bolt to it. I've found a 12" steel fixture plate that is made from 1/2" plate that I intend to bolt to my 7-1/2" faceplate. It just needs threaded holes in the right spots to mount it, and more holes added as necessary for the various setups. The question will be whether it is true and flat, but I intend to bolt it to my smaller faceplate and then face it off in the lathe, which will true it up well enough for anything I do. I have no issue drilling holes in that plate for special fixtures, but I wouldn't want to drill random holes in a cast iron faceplate.

(Actually, I have several 12"-diameter fixture plates with open holes in the middle that could be mounted like that, but more is better.)

I don't own a mill, so I'll be using the fixture plate and the milling attachment to make stuff possible that wouldn't be otherwise.

As to its value for those who DO own a mill, it takes a pretty big mill to be able to mill flat a surface that is 10 or 12" in diameter. But that's not that difficult by using the toolpost as a trapanning tool for facing the surface of just about anything that can be bolted to the faceplate and spun without hurting people. The South Bends have the power and the slow speeds needed to get that job done on bigger stuff.

Rick "who would never use a crescent wrench as a hammer when there is a perfectly good pipe wrench available for hammering" Denney

 

[benmychree]

In some situations the taper adaptor can be made from a regular MT reducing sleeve, by simply cutting the tang end off.

 

[pontiac428]

I call a large plate that you can bolt parts to a face plate. I call a small plate for turning on centers a dog drive plate. They're two different tools.

Dog drive plates usually have little more than a slot to drive the dog with. Mine is a demure 8" plate in D1-6, with no other features. Provides lots of room to work around while on centers, and no cheese grater features/nothing to bloody my knuckles against.

I don't use a face plate much, but they are very versatile. I would not consider 6061 a viable material for a face plate. It may be easier to handle, but the larger the diameter, the more tool deflection you'll see in a facing cut. Young's modulus is 3x higher for steel than for aluminum, so the deflection will be 3x greater for the same amount of force applied. That's a LOT!! A salvaged steel round, either cut from plate or from bar stock, should not be cost prohibitive compared to the same slug in chill cast 6061. So other than weight when mounting/dismounting the tool, there is no advantage whatsoever in choosing aluminum to build it with.

 

[rwdenney]

In some situations the taper adaptor can be made from a regular MT reducing sleeve, by simply cutting the tang end off.

Not with an S-series South Bend lathe as used by the person to which I was responding, which uses a proprietary taper for the inside of the spindle. The taper is the same as a larger MT, but the diameters are significantly different.

Rick "not that hard to make one, if the lathe has a taper attachment" Denney

 

[Chewy]

Pontiac428, I was going to use 6061 plate not cast. I was thinking of a large area to bolt small items on. Right now, with a 4 jaw I can't go much beyond a 6" item, because the jaws stick out too much. Depends on where I am on the part. I end up using the mill. McMaster has 12" x 3/4" for $87. Might look at 5/8" steel pate. Not doing big heavy items like Abom79, just small repair items that are hard to hold. My PM 1228 lathe hasn't got the guts to swing anything heavy.

 

[rwdenney]

I call a large plate that you can bolt parts to a face plate. I call a small plate for turning on centers a dog drive plate. They're two different tools.

Dog drive plates usually have little more than a slot to drive the dog with. Mine is a demure 8" plate in D1-6, with no other features. Provides lots of room to work around while on centers, and no cheese grater features/nothing to bloody my knuckles against.

I don't use a face plate much, but they are very versatile. I would not consider 6061 a viable material for a face plate. It may be easier to handle, but the larger the diameter, the more tool deflection you'll see in a facing cut. Young's modulus is 3x higher for steel than for aluminum, so the deflection will be 3x greater for the same amount of force applied. That's a LOT!! A salvaged steel round, either cut from plate or from bar stock, should not be cost prohibitive compared to the same slug in chill cast 6061. So other than weight when mounting/dismounting the tool, there is no advantage whatsoever in choosing aluminum to build it with.

You are making (with better terminology) the distinction I was trying to make, between cast-iron dog plates and proper faceplates for fixturing.

The 11" plate I bought with the correct threads for my spindle is really a dog plate--cast iron with slots only. But it has four slots and I'll bet I can fixture most stuff using it, one way or another. The steel plates I have are better.

You can account for the difference in stiffness with aluminum by making it thicker, but then you lose the weight advantage (aluminum is one-third the stiffness of steel, and also one-third the density of steel).

A heavy plate helps the lathe maintain momentum for interrupted cuts, too. And almost all milling using a face plate on a lathe will involve interrupted cuts.

For that matter, some of the larger 4-jaw chucks of old came with T-slots for use as a faceplate, with the jaws removed.

Rick "wishing one of his plates had T-slots" Denney

 

[tailstock4]

The first picture I would call a drive plate with a lathe dog on a Southbend Heavy 10. It is being used with a soft center that was trued in a 5C collet and its adapter.

The second picture is a face plate for my American Pacemaker. As to whether face plates are really necessary, I personally think anytime you can expand the capability of a shop or a machine is a good thing. It can give you options on different ways to get a job done. In other words, not just “if I can get it done” but “what would be the best way to do it”.