Smithy 1220 taper

[ShagDog]

Do you have a smithy 1220?

No. Never even seen one.

 

[mac1911]

No. Never even seen one.

I dont think there are “highly accurate” to begin with.
Chinese 3-1 machine 5” chuck
500lb unit. IIRC accuracy claim is .001” ?
Its to cold now to try anything but I hope to pick up a .0005” indicator and see if I can manipulate the gear head Pin and set screws 69-70 on the diagram
I was thinking of loosening the front a smidge and tightening the rear? Hopefully by spring I will have nice chunk of drill rod or so to run the dial indicator on and look for any miss alignment. I think my tail stock is nose diving also.

 

[ShagDog]

Mac, this is getting too complicated for me. My lathes do not have an adjustable headstock. But, the first thing to do is try to get out any twist you may have in the bed ways, assuming they are not worn too badly. You need a good machinist level. Review threads on "leveling". Then I would move to the headstock adjustment, if bed way alignment does not do the trick.

I don't know the method that is used to check alignment of the bed ways to the headstock.

Edit: see my post below (post # 19)

 

[mac1911]

Mac, this is getting too complicated for me. My lathes do not have an adjustable headstock. But, the first thing to do is try to get out any twist you may have in the bed ways, assuming they are not worn too badly. You need a good machinist level. Review threads on "leveling". Then I would move to the headstock adjustment, if bed way alignment does not do the trick.

I don't know the method that is used to check alignment of the bed ways to the headstock.

Thanks , im getting there.
The machine does not have much wear other than the lead screw nuts.
I was told this was from lack of correct set up and to tight of gib adjustments.
I will eventually come across a level

 

[ShagDog]

Thanks , im getting there.
The machine does not have much wear other than the lead screw nuts.
I was told this was from lack of correct set up and to tight of gib adjustments.
I will eventually come across a level

Good luck. You may be able to get away with using a regular level to at least see if you are in the ballpark. That would be a good start.

Edit: see my post below (post# 19)

 

[Alcap]

From reading threads here with others trying to check , tapers , bearings etc. They all started with the machine run to get all the bearings up to operating temperatures. If it was up to temperature then next time I was testing I would run an indicator along the finished shaft to see was it the same along the shaft , or maybe deflection causing the taper . Your getting .0008” in 4” , being only .0004 a side . You could even set the indicator at the very end of the shaft and gently see if there’s deflection .

 

[mac1911]

Good luck. You may be able to get away with using a regular level to at least see if you are in the ballpark. That would be a good start.

Im level by carpentry standards with a 4’ johnson.

 

[mac1911]

From reading threads here with others trying to check , tapers , bearings etc. They all started with the machine run to get all the bearings up to operating temperatures. If it was up to temperature then next time I was testing I would run an indicator along the finished shaft to see was it the same along the shaft , or maybe deflection causing the taper . Your getting .0008” in 4” , being only .0004 a side . You could even set the indicator at the very end of the shaft and gently see if there’s deflection .

Which I plan to do . Just need a better indicator. Right now I have a inexpensive one .001”
I have a .0005” indicator but no proper way to mount it. I think its a enco , dial glass is very discolored and hard to see through
The dovetail adapter does not fit any of the rods I have on my stands? I plan on making something that fits come spring time.
Shop is to cold now

 

[ShagDog]

From reading threads here with others trying to check , tapers , bearings etc. They all started with the machine run to get all the bearings up to operating temperatures. If it was up to temperature then next time I was testing I would run an indicator along the finished shaft to see was it the same along the shaft , or maybe deflection causing the taper . Your getting .0008” in 4” , being only .0004 a side . You could even set the indicator at the very end of the shaft and gently see if there’s deflection .

Oop's . My bad. I was reading the smaller end (headstock) of the turning as being .8805" and not .8885". I was coming up with taper of .0088". After looking at your post, Alcap, I went back and saw it is actually .8885", which as you correctly stated only .0008" taper. Big difference.

So, Mac, the taper is nowhere near what I thought. It is fine as is; but, I would for my personal preference like closer to almost zero, which you may be able to achieve by shimming. I don't know how your lathe is set up; but, you may want to check out Blondihacks You Tube video on leveling a lathe.

 

[mac1911]

Oop's . My bad. I was reading the smaller end (headstock) of the turning as being .8805" and not .8885". I was coming up with taper of .0088". After looking at your post, Alcap, I went back and saw it is actually .8885", which as you correctly stated only .0008" taper. Big difference.

So, Mac, the taper is nowhere near what I thought. It is fine as is; but, I would for my personal preference like closer to almost zero, which you may be able to achieve by shimming. I don't know how your lathe is set up; but, you may want to check out Blondihacks You Tube video on leveling a lathe.

I get the concept of leveling the lathe.
My concern is the head stock was loose when I picked up this lathe.
So I guess im at a point
When do I call it “good” on the gear head and move on to the ways?
The next warm weekend I will try to get a indicator set up and see if I can get some movement on part 69 and 70.

I can tell you the lathe has come along way since I got it and started cleaning it up and checking/fixing

Im still trying to figure out where the gear oil went. It was pretty much empty when I got it.