Lathe dog question

A ghetto dog (or should I say junkyard dog) will often do in a pinch. I have a bunch of them.
 
Face Plates & Drive Plates: A face plate sized for a machine will generally be larger than a drive plate sized for the same machine. The face plate will normally have narrower slots and none of the slots go all of the way out to the OD of the plate. They are used to hold odd shaped stock or castings that you can't hold in a 3-jaw or 4-jaw chuck for one reason or another. The drive plate will normally also have four slots but they would be wider than the slots in the properly sized face plate and one of them will normally be cut all of the way to the plate OD. That is the slot that you normally put the dog tail into. The reason is so that you can dismount the work piece with dog still attached by backing out the tail stock ram only maybe a quarter inch. So it saves time and doesn't disturb the set up.

If you walk into a machine tool vendor's store and ask for a 3MT to 2MT reducer, what the counter guy/gal will hand you unless you are a little more specific will be about 6" long and will put the 2MT center much too far out for the dog leg to fit the drive plate. With their 10" and 12" lathes, Atlas supplied a 3MT to 2MT adapter that fit almost flush with the end of the spindle nose. And they supplied two 2MT dead centers. When you installed the adapter and center, the point of the center was about where it would have been had the spindle taper been 2MT. That is what you need to use with a drive plate. A 3MT dead center will stick farther out relative to the drive plate and might or might not work.
 
Dogs, an interesting subject. I used to have Lady and Sassy. Lady was Mom's pet and Sassy was Dad's little girl. (Scotty) She lived to 15, a ripe old age for dogs. I never allowed them into the shop, feared they would pick up chips in their pads.
Oh, wrong dogs. . . Sorry, I got distracted. Rascal is fussing at something in the back yard as I type.

You're asking after lathe dogs. I have a number of dogs of varying sizes and shapes But for much work, albeit small, I just make what I need at the time. Sometimes it's not true round or some odd shape that is too "fragile" to mount to the face-plate. All that's needed is a couple of pieces of re-bar or key stock or whatever is handy. And some machine screws. Something to clamp up what you're working on. And a screw as the drive pin.

I use a face-plate as the drive plate most times. It will fit a 7/16 bolt as the drive pin. Although I usually don't get that big. Also, the face-plate gives me a place to hang counter-weights to balance things a bit. I will concede I don't do fancy work like a lot of folks on here. But home-made anything is my forte'. I'd much rather make what I need when I need it. Just my nature. . .

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Don't have any dogs. This is my work around to turn something between centers. I put a dead center in the headstock and a live center in the tailstock. If the work will fit in my ER32 collets I used the collets in my collet chuck to drive the work. If the works is bigger than 3/4" I use my 6" 4 jaw chuck to drive the work. Cram the work piece as tight as I can between the centers and then carefully tighten the 4 jaw so as to not throw the work piece off the centers. Loosen the tailstock center so that it will spin.

I have not tried this and have no idea if it would work. If I can't use the above for whatever reason I have thought that I would weld/braze/silver solder a bolt/rod to the work. The bolt/rod would fit in the drive plate and drive the work. I can think of several variations on this.
 
One thing about commercial dogs is the castings are smooth and the edges rounded. That means potentially banging a knuckle vs. sticking your hand in a blender with the duct tape and bent up wire hanger method. If you watch the estate sale or "machinist lots" on eBay, dogs turn up (pun intended) for a good value now and again. They're meant to be quick and easy to use, and should be confidence-inspiring, secure, and safe.
 
In this "business", a jury rig is seldom acceptable and definitely not if there is any risk of bodily harm.
 
Ebay has a 6" dia drive plate for around $80 shipped. Is that a reasonable price?

The MOLO does not have a listing for the chuck or any drive plates. Any reason why? I did find L5-365 for a face plate, that is 8-1/2" in dia. $85 shipped. Is that reasonable?

I didn't learn to use lathe dogs with a plate. I just set the bent arm in one of the jaw slots with a dead center in the chuck and a live center in the tail stock. The drive plates are the same diameter as the check anyway.

I bought 1-1/4", 1-1/2" and 2" lathe dogs from McMaster-Carr.
 
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