Mystery Project...

I would see no need to ever disengage the rollers once there set to move freely with minumum play. I would have at least 4 rollers(one on each corner) and the locking mechanism seperate. That way when it locks it wouldnt be putting any forces on the bearings, in fact just the opposite. Just my 2 cents worth.
 
Yep, I agree. I left 1" of space in front and behind the locking plate to possibly put another plate below it that has rollers or bearings. If the undersides of the ways are both parallel and coincident I'll go with one roller in front and one in back. Each roller will contact both sides of the ways. If the undersides are not coincident, I'll go with 4 individual bearings. Anyhow the plates will work independently. I did for a while think I'd put the rollers on the existing locking plate and just have them swing out of the way when not needed. There's plenty of clearance for either method.

EDIT: And I fully realize this is not an ideal way of holding down a drilling mechanism. It's perfectly safe but there will be some tendency to lift-up maybe a thou or two -but it's manageable. When I want to do precision drilling, it's done on the mill or if on the lathe, it's rough drilled first followed-up with a boring bar mounted on the QCTP. -Bases are covered.


Ray

I would see no need to ever disengage the rollers once there set to move freely with minumum play. I would have at least 4 rollers(one on each corner) and the locking mechanism seperate. That way when it locks it wouldnt be putting any forces on the bearings, in fact just the opposite. Just my 2 cents worth.
 
Will do... the last couple days, I've been working on some other parts for folks and also, the day-job has got me kinda busy too...


Ray

Keep us posted Ray, facinating build!
 
Its been a while since i adjusted a carriage Ray, but every thing we do in this business is a give and take. drills and reamers push off, just a fact of life. I feel certain you set your turrett up like a carriage and everything willl be more than acceptable.
 
Yes, thanks... I think/hope it will be fine. I guess if I wanted the performance of a Hardinge or Monarch, I'd buy one. Drilling is a "crude" operation in the first place. For the kind of work I do and foresee doing, as long as the starting hole is within a couple thou of where I want it, other operations (such as endmill or boring) can fix the rest. -That's my story and I'm sticking to it :whistle:.

BTW: With any luck, later today, I plan to work on the push/pull mechanism for the top plates. It will be a single, internal screw whose position is fixed (and not engaged) with the bottom of the two top plates and top plate will have a threaded semi-hole. As the screw is turned, it pushes the top plate a desired amount.

One of the reasons I built this thing like a brick xxxxhouse is that I really hate trying to adjust sideways motion of the TS to get a shaft centered. This is also why I put two dovetail guides in the top plates. The traditional tailstocks have a lot of slack and wiggle and even though you push it in the proper direction, it seems to go the other way until the slack is pulled-out. Heaven forbid you overshoot and need to backtrack the direction. I'm hoping (fingers crossed) this mechanism is more precise. Later on, I'll make an attachment to accommodate a DI to see exactly how much the adjustment is.

All these little improvements (if they are successful) are real time-savers in the longrun. Aside from that, this is just a fun project that makes you feel like a hero :)

Ray



Its been a while since i adjusted a carriage Ray, but every thing we do in this business is a give and take. drills and reamers push off, just a fact of life. I feel certain you set your turrett up like a carriage and everything willl be more than acceptable.
 
Never ran a harding, but i fell in love with monarchs 1/4 century ago. We i was an apprentice we had 2 monarchs 2 colchesters 2 leblonds A planer a big shaper a horizontil cincinatti, a big verticle cincinatti milatron a supermax and a brand new bridgeport had a surface grinder, a big drill sharpener two radial arm drills belt sander several bench grinders we had a big lathe with a 50 inch swing and bout a 200 inch bed but i dont remember the name. I really miss that old shaper.We have a couple of TOS lathes now and they are pretty good lathes, Still have both the monarchs, the small colshester and the chinese boring mill. We have a sharp mill which is a bridgeport clone and i like it better than the bridgeport.
 
In case that description of the push/pull mechanism wasn't clear, here's some pics...

First, a center hole (1/2x13) was drilled and tapped right between the two plates. Not shown (but you'll see later) a 1/4" hole was drilled at the bottom of tapped hole. The area around the hole was milled flat to later accommodate a metal retaining plate for the adjustment screw.

Center Hole.JPG


Once the tapping was finished, the plate that's fixed was milled to remove the threads from that half of the hole. The semi-circle was bored to 9/16".

Enlarging.JPG

Now it might start making sense why the extra hole was drilled. I'll make a special screw that has a leading piece on the end that will support the end of the bolt; otherwise, it would just drop down into the 9/16" side of the semi-circle.

End Support.JPG

Here are the mated pieces. The special screw thats made will be held in the front by the fixed plate. I'll put some collars on the front of the screw and a metal plate will support the front part of the screw. I though it would be nice to use an ACME thread but, I don't have ACME taps on hand -and they're quite expensive. A 1/2-13 will have to do. When the adjustment screw is turned, the bottom/fixed plate will remain stationary and the top plate that supports the Morse holder disk will slide in the keyed grooves.

Mated Pieces.JPG


Taking a step backward in time, here's a shot of tapping the holes for the plate that will support the front of the screw. What I really wanted to point-out here is how the mill spindle is used to hold the tap straight. There's a pointy piece in the chuck that either fits in the divot in the end of the tap or, it fits well enough into the opening of the tap handle. I apply light pressure with the spindle for the first few turns. BTW: I made that tap handle when I was about 13 years old in my dad's garage shop. One of my favorite tools in the shop and everyone who uses it wants me to make them one -and I usually do. I can make them in my sleep.

Tapping.JPG

Hopefully tomorrow, I'll have time to make the adjustment screw.

Until we meet again...

Ray

Tapping.JPG Center Hole.JPG Enlarging.JPG Mated Pieces.JPG Screw 1.JPG End Support.JPG
 
So, I came-up with an idea for the rollers under the way rails to keep the TS down when drilling... What do you think of this? How about a heavy piece of band steel that would act similar to a leaf spring? I could mount the bearings/rollers to the piece and it would operate just like the normal locking plate but, it would have adequate tension to keep it flat on the ways.

Thoughts? Any ideas for a suitable piece of metal that could serve as a "leaf spring". I have proper heat treating equipment so, I could make something with a cutom temper. The piece will need to be about 3.5" wide and 5-6" long (roughly). Ideas about what would be a good metal to start with are greatly appreciated.


Ray
 
A few more visuals on the push/pull adjusting knob.

Roughed it out pretty much by eyeball and cut the collar with the parting blade.


Adjusting Knob Parting.JPG

Here's a few views of it in place. It's a little stiff but a few moments on the wire wheel and some grease will fix that. I need to form a knob or a hex or just drill some holes through to put put a little leverage bar so it can be turned by hand. It works though. Now I just need to make the front plate that retains it by the front collar. We'll take care of that after dinner.


Adjusting Knob 2.JPGAdjusting Knob Profile.JPGAdjusting Knob In Place.JPG

PS: We just had the most intense 20 minutes of rain that I can recall in years. The skies clouded up all the sudden and wham! The dog bowl in the front lawn, which is about 4" deep, was empty and 20 minutes later it was full. -Weird!...


Ray

Adjusting Knob 2.JPG Adjusting Knob In Place.JPG Adjusting Knob Parting.JPG Adjusting Knob Profile.JPG
 
Back
Top