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Robo
01-30-2010, 10:48 PM
Wondering what you guys think of making a tailstock ram on a lathe that doesn't have a tailstock ram? possible? Its a rockwell lathe and its missing the guts to the tailstock casting and I have been thinking of making one. Only problem is the rockwell is the only lathe I have. Lathe does have a taper attachment and steady rest.

What material would you use?

What order would you machine the ram in?

I would love to just find one of these but it would be so rewarding for me to machine one myself. I know of a guy who has the screw and handwheel. Let me know what you guys think.

gary hart
01-30-2010, 11:11 PM
Sometimes you can get lucky, happened to me. Wanted too change tailstock to lever feed. Found piece of shafting that was a good fit in tailstock bore. You can buy a Morse Taper socket that has a straight outside diameter. Enco used to sell them. If you can get one that will work, and can bore out for the socket you will have good start on one.

rklopp
01-31-2010, 12:28 AM
I'd make a ram out of ETD-150, which I think is prehardened 4140, perhaps resufurized for machiniability. In any event, it's hard enough for a tailstock ram but machines nicely. You can get it from McMaster. I'd get a piece long enough for the job, plus some extra for chucking. First, hone (or have someone else hone) the tailstock bore clean, straight, and without taper. Do the honing with the ram lock fixed in place somehow. For example, if the lock is achieved by squeezing a split, shim the split open slightly, and tighten the lock lever. If the lock is a split cotter, figure out a way to similarly shim or glue it in place and lock it. The exact bore diameter is immaterial. Make an aluminum plug gauge on a threaded rod stick to probe the bore and make sure it's not tapered. Make the plug about two diameters long. Once you get a plug gauge dialed in (you might have to make a couple to get the fit just right), you will know what diameter the ram should be. The turn the ram using the steady. Rough out the ID using drills and boring tools. Work the OD to a thousandth or two oversize. Work in short stages along the length, as you'll have a tough time getting the steady dialed in such that the lathe will turn straight over any appreciable length. Mill the keyway. Then, lap the ram to fit. Next, hold the ram in a 4-jaw with soft shims against the chuck jaws and dial it in as close as possible for concentricity and parallelism, and finish the part where the feed nut goes. Reverse, and rough-turn the Morse taper using the compound.

Install the ram and shim and scrape the tailstock base as necessary to get the best headstock-tailstock alignment you can. Then, put a center in the headstock and use it to support a Morse taper finish reamer restrained by a wrench or tap wrench. Use the tailstock handwheel to feed the ram onto the reamer as you turn it with the wrench. It takes a lot of pressure, even with a sharp reamer. Clean and check with a blued male taper of high quality, such as a taper gauge or good center. Repeat reaming, cleaning, and checking until you are satisfied with the fit. Finally, engrave the graduations and numerals as you see fit.

I manufactured a new ram this way when rebuilding the tailstock of my Monarch 10EE, except I had a second lathe with functional tailstock, so I could turn the OD between centers. Nevertheless, I used the steady when working the ram bores. The worst part was probably drilling the axial through hole - it was an awfully deep hole, even when drilled from each end. I used a 5C collet holder on my quick-change toolpost so i could feed the drill using the lathe's saddle.

I think the ram probably came out better than factory original.

lakeside53
01-31-2010, 03:01 AM
A friend of mine almost went though the same process.... On an Emco Maximat 7. Then he found that a Grizzley lathe used an exact copy of the Maximat tailstock ram. $15 later... it was done.


You may be able to find a ram that is the correct size or slightly larger. Bore the tailstock casting to suit.

Robo
01-31-2010, 11:06 AM
I'd make a ram out of ETD-150, which I think is prehardened 4140, perhaps resufurized for machiniability. In any event, it's hard enough for a tailstock ram but machines nicely. You can get it from McMaster. I'd get a piece long enough for the job, plus some extra for chucking. First, hone (or have someone else hone) the tailstock bore clean, straight, and without taper. Do the honing with the ram lock fixed in place somehow. For example, if the lock is achieved by squeezing a split, shim the split open slightly, and tighten the lock lever. If the lock is a split cotter, figure out a way to similarly shim or glue it in place and lock it. The exact bore diameter is immaterial. Make an aluminum plug gauge on a threaded rod stick to probe the bore and make sure it's not tapered. Make the plug about two diameters long. Once you get a plug gauge dialed in (you might have to make a couple to get the fit just right), you will know what diameter the ram should be. The turn the ram using the steady. Rough out the ID using drills and boring tools. Work the OD to a thousandth or two oversize. Work in short stages along the length, as you'll have a tough time getting the steady dialed in such that the lathe will turn straight over any appreciable length. Mill the keyway. Then, lap the ram to fit. Next, hold the ram in a 4-jaw with soft shims against the chuck jaws and dial it in as close as possible for concentricity and parallelism, and finish the part where the feed nut goes. Reverse, and rough-turn the Morse taper using the compound.

Install the ram and shim and scrape the tailstock base as necessary to get the best headstock-tailstock alignment you can. Then, put a center in the headstock and use it to support a Morse taper finish reamer restrained by a wrench or tap wrench. Use the tailstock handwheel to feed the ram onto the reamer as you turn it with the wrench. It takes a lot of pressure, even with a sharp reamer. Clean and check with a blued male taper of high quality, such as a taper gauge or good center. Repeat reaming, cleaning, and checking until you are satisfied with the fit. Finally, engrave the graduations and numerals as you see fit.

I manufactured a new ram this way when rebuilding the tailstock of my Monarch 10EE, except I had a second lathe with functional tailstock, so I could turn the OD between centers. Nevertheless, I used the steady when working the ram bores. The worst part was probably drilling the axial through hole - it was an awfully deep hole, even when drilled from each end. I used a 5C collet holder on my quick-change toolpost so i could feed the drill using the lathe's saddle.

I think the ram probably came out better than factory original.

I think I read your thread on PM on building your 10ee ram. I don't have a "lap" or a hone that is suitable for this job (I have some cylinder hones but that is it).

rklopp
01-31-2010, 01:35 PM
I farmed out the honing and made the lap.

Robo
01-31-2010, 03:35 PM
I farmed out the honing and made the lap.

What does a lap consist of?

MDSpencer
10-22-2011, 01:25 PM
http://flic.kr/p/aw7gUP I think it came out nicely.

Mark