[Shaper] Little problem with shaper table

[peacock]

Think about this, the inner screw if it is 1.375 before threading would wieght 17/18 lbs per foot. the outer with a 1 5/8 bore and a2 3/8 OD will weight about 28 pounds per foot. That cross section in compression will handle tons. Look at the size of the extension shaft that screws out of a 8 ton bottle jack.

The vertical ways take the biggest part of the shock. By far the most of the vertical travel is thru the head. I use my shaper all most every day, and some days I never change the table height.

As far as load I would consider a high stres/load app. to be something like a screw press or even a bottle jack or sometimes the lead screw in a lathe or mill. This only really needs to be stronger than you are as you are the power source.

That hammer frame is about 800 lbs and I have had some on there that were 1,300 pounds. The jack screw is 1.25 dia. I have been useing this like this for 20 years with no problems.

 

[Tom Griffin]

Ron,

I'm not sure why you feel the need to re-make any of the screws or nuts. They didn't fail from wear, the pins holding them together failed from abuse and their only purpose in life is to keep the nuts from rotating with the screws. I would just clean them up, repair the damaged pins and put 'em back together. If, for some reason that isn't possible, ordinary 1018 steel would be fine for the screw and bronze would make an excellent nut. Strength is simply not an issue here since these screws are WAY over engineered. For a frame of reference, a 1"-10 Acme screw made of mild steel has the column strength to safely support around 15000 pounds. What is the size of your smaller screw? I suspect that it alone would be strong enough to lift at least five of your shapers completely off the floor.

Tom

 

[ScrapMetal]

View attachment 34877View attachment 34878View attachment 34879Think about this, the inner screw if it is 1.375 before threading would wieght 17/18 lbs per foot. the outer with a 1 5/8 bore and a2 3/8 OD will weight about 28 pounds per foot. That cross section in compression will handle tons. Look at the size of the extension shaft that screws out of a 8 ton bottle jack.

The vertical ways take the biggest part of the shock. By far the most of the vertical travel is thru the head. I use my shaper all most every day, and some days I never change the table height.

As far as load I would consider a high stres/load app. to be something like a screw press or even a bottle jack or sometimes the lead screw in a lathe or mill. This only really needs to be stronger than you are as you are the power source.

That hammer frame is about 800 lbs and I have had some on there that were 1,300 pounds. The jack screw is 1.25 dia. I have been useing this like this for 20 years with no problems.

Thanks Peacock that does help put things in perspective. I have to ask though, what is that project you have on the shaper? There has got to be a story behind that one. :thumbzup:

Ron,

I'm not sure why you feel the need to re-make any of the screws or nuts. They didn't fail from wear, the pins holding them together failed from abuse and their only purpose in life is to keep the nuts from rotating with the screws. I would just clean them up, repair the damaged pins and put 'em back together. If, for some reason that isn't possible, ordinary 1018 steel would be fine for the screw and bronze would make an excellent nut. Strength is simply not an issue here since these screws are WAY over engineered. For a frame of reference, a 1"-10 Acme screw made of mild steel has the column strength to safely support around 15000 pounds. What is the size of your smaller screw? I suspect that it alone would be strong enough to lift at least five of your shapers completely off the floor.

Tom

Tom, both you and Peacock have definitely put the numbers on for what I was questioning as far as stress and load. (Though I still need someone to define what "stress proof" means. ) The only thing that I am looking into a replacement for at this time is the acme threaded sleeve (outer screw). The top "nut" is easily re-used by just drilling and tapping the opposite side from where the original screw was. What you are both saying about using the original sleeve is absolutely true, I have no doubts, and it would be the correct path to follow if I needed this machine to "bring home the bacon", was on the clock, etc. I'm pretty sure that it is obvious by now that I'm not a professional in metal working though I am working hard at absorbing all I can. Just making repairs is part of the learning process right now.

It may seem a bit foolish but I still feel that I need to explore the possibility of making a new sleeve if for no other reason than "it's my nature". I can easily improvise to come up with a solution or "do what is necessary" to get something operational again if it's imperative that I do so. Now, in the case of building/repairing something for myself, when in no hurry, I'm all for "making it like/better than new" and over-engineering. :biggrin: Once I have a better idea of just what it will take to make the "perfect" repair I can make a decision on whether or not it is worthwhile to pursue or just fall back and make due with what I have at hand.

Thanks again guys.

-Ron

 

[Tom Griffin]

It may seem a bit foolish but I still feel that I need to explore the possibility of making a new sleeve if for no other reason than "it's my nature". I can easily improvise to come up with a solution or "do what is necessary" to get something operational again if it's imperative that I do so. Now, in the case of building/repairing something for myself, when in no hurry, I'm all for "making it like/better than new" and over-engineering. :biggrin: Once I have a better idea of just what it will take to make the "perfect" repair I can make a decision on whether or not it is worthwhile to pursue or just fall back and make due with what I have at hand.

Thanks again guys.

-Ron

Well if you want to do it just for the fun of it, that's an entirely different story. Just be sure you have the capability to bore or drill out the center of that outer screw before investing in the steel.

Tom

 

[ScrapMetal]

Hmmm, I could maybe use that as an excuse to "upgrade" my machinery/tooling!

Tom, that was actually going to be one of my next questions. If I can't find what I want in a "tube" what equipment and tooling would I need to bore 1.5" hole in a 9" solid steel cylinder and/or is my SB 11" even capable of that?

Learning, learning, learning... :biggrin:

-Ron

 

[Tony Wells]

Ron,
I was gone all day, up until now and didn't get a chance to check that tubing.

On your question on Stressproof:

http://www.niagaralasalle.com/pdf/stressproof.pdf

Very popular for shafting. Good stuff for general purpose machine parts.



If I needed a 1.50" hole through a bar, and I intended to bore it, I'd punch halfway with an 1 1/2" drill, and flip it. If I didn't need to bore it, but wanted no steps in the middle, I'd drill it all the way from one end. Your issue would be boring it from both ends if it needed to be slick and concentric all the way through to ID. Not that it couldn't be done. There are a couple of approaches that would get you there. 9" isn't too far to bore, as long as you roughed it out from both ends and didn't need to remove a lot of material with a long bar. As far as your lathe doing it, probably. Maybe not efficiently, but that falls in importance when you are doing it for yourself.

What material you choose isn't all that critical. I lean towards the 41XX and 43XX materials because I can rely on them, and I am used to cutting them. I like the finish I can get that is tougher to get on the lower carbon, softer steels. On a small piece like you need, the cost difference is negligible. Especially if I find piece....it will be free. In bronzes, I'd probably go with one of the aluminum bronze choices. SAE 660 is soft, absorbs shocks well, and won't wear your screws very fast. I'm sure that's part of Tom's reasoning, and I can't fault that a bit.

 

[Tom Griffin]

Tom, that was actually going to be one of my next questions. If I can't find what I want in a "tube" what equipment and tooling would I need to bore 1.5" hole in a 9" solid steel cylinder and/or is my SB 11" even capable of that?

Learning, learning, learning... :biggrin:

-Ron

Ron,

Big parts require big tooling: I would drill it it from each end with a 1" drill and then bore it to size from each end with a 3/4" boring bar. A steady rest will be needed to support the end of the bar for this boring job.

What size taper is in your tailstock? The 1" drill will probably be an MT3 so you may need an adapter.

As Tony suggested, aluminum bronze would make an excellent nut. I would also throw a grease fitting in it for good measure.

Tom

 

[ScrapMetal]

Ron,
I was gone all day, up until now and didn't get a chance to check that tubing.

On your question on Stressproof:

http://www.niagaralasalle.com/pdf/stressproof.pdf

Very popular for shafting. Good stuff for general purpose machine parts.



If I needed a 1.50" hole through a bar, and I intended to bore it, I'd punch halfway with an 1 1/2" drill, and flip it. If I didn't need to bore it, but wanted no steps in the middle, I'd drill it all the way from one end. Your issue would be boring it from both ends if it needed to be slick and concentric all the way through to ID. Not that it couldn't be done. There are a couple of approaches that would get you there. 9" isn't too far to bore, as long as you roughed it out from both ends and didn't need to remove a lot of material with a long bar. As far as your lathe doing it, probably. Maybe not efficiently, but that falls in importance when you are doing it for yourself.

What material you choose isn't all that critical. I lean towards the 41XX and 43XX materials because I can rely on them, and I am used to cutting them. I like the finish I can get that is tougher to get on the lower carbon, softer steels. On a small piece like you need, the cost difference is negligible. Especially if I find piece....it will be free. In bronzes, I'd probably go with one of the aluminum bronze choices. SAE 660 is soft, absorbs shocks well, and won't wear your screws very fast. I'm sure that's part of Tom's reasoning, and I can't fault that a bit.

Good read on the "stress proof" Tony, thanks for that. Like I said before though, no hurry on looking for the piece but there is no way I can let you just "give" it to me. I'll have to get back at you somehow.

Ron,

Big parts require big tooling: I would drill it it from each end with a 1" drill and then bore it to size from each end with a 3/4" boring bar. A steady rest will be needed to support the end of the bar for this boring job.

What size taper is in your tailstock? The 1" drill will probably be an MT3 so you may need an adapter.

As Tony suggested, aluminum bronze would make an excellent nut. I would also throw a grease fitting in it for good measure.

Tom

From what you both are saying I think I already have the tooling it would take to get the job done or at least a good portion of it. It would be a bonus that I have a project where I finally get to use my steady rest, a toy that I haven't got to play with yet. My tailstock taper is MT2 but I'm sure I could get it worked out.

A grease fitting? Hmmm, that would go with my "over engineered" and "better than new" philosophy, I like it! :thumbzup:

I don't know if I've said it enough but I can't tell you guys how much I appreciate the input you've all given.

Thanks,

-Ron

 

[peacock]

Be fore I got too deep in this project I would get a piece of cheap stock the same diameter of the inner screw and pratice cutting a left hand square thread. Several aspects of this to be considered, grinding tool bit for square thread is a big one. I say the inner shaft because will give you a nut to test fit with and not haveing to spend a bunch of money . You will only need to cut the length of the nut to get a good idea of the process. Once you build your skill and confidence you can move up to the real thing. If you decide to go with an acme thread then you will need to learn an internal left hand thread. When you master this it will be a nice addition to your trick bag.

 

[Tony Wells]

A little technical correction is due. I mentioned "P80" earlier. I was going by an obviously faulty memory. "L80" is a mechanical property requirement of an alloy steel that is a controlled yield, fairly soft steel (22 Rc max.) in the 4XXX series. I should have said "P110" in referencing the tubing I have I thought might work for you, Ron. It is P110 that I have, with a 3.00 OD and 1 1/2" ID. ID is a little rough, so if it's close to what you need, I'll measure it cloers. I used a yo-yo. It specs 30-36 Rc.

Sorry for any confusion.