Cross side extension build.

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SmithDoor

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Please comment on build
Screenshot_20231226-091237_Drive.jpg

This what I am planning on doing .
Instead of mill the carriage I am moving the not ¾" and ¼" back for a full 4" movement and a stop for auto feed cross slide later.

Adding a ¾" spacer for full stoke.

Dave
 

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  • CROSS FEED SCREW DEC 25 2023 Model (1).pdf
    23.2 KB · Views: 0
Please comment on build
View attachment 152440
This what I am planning on doing .
Instead of mill the carriage I am moving the not ¾" and ¼" back for a full 4" movement and a stop for auto feed cross slide later.

Adding a ¾" spacer for full stoke.

Dave
I am not a machinist so I am not much help, but like your idea. I hope it works out.
Will be following your progress with great interest.
 
I am not a machinist so I am not much help, but like your idea. I hope it works out.
Will be following your progress with great interest.
I have used this on larger lathes and mills.
On one mill exstend over 10".

When look on internet everyone would mill on a mini lathe. Then a complex way if avoiding making a new screw.

If make a new feed screw I do not need to mill just move the nut.

Dave
 
I have used this on larger lathes and mills.
On one mill exstend over 10".

When look on internet everyone would mill on a mini lathe. Then a complex way if avoiding making a new screw.

If make a new feed screw I do not need to mill just move the nut.

Dave
If you change (lengthen) the screw, won't you also need to lengthen the cross-slide body also? What happens to ridgidity when the present cross-slide extends too far?
 
If you change (lengthen) the screw, won't you also need to lengthen the cross-slide body also? What happens to ridgidity when the present cross-slide extends too far?
The good news others have add to threads and works .
The mill the casting I am moving the nut still the same length of screw.

Screenshot_20231227-112825_Drive.jpg
 
If you change (lengthen) the screw, won't you also need to lengthen the cross-slide body also? What happens to ridgidity when the present cross-slide extends too far?
If look the South Bend 9A and 10K they use about 6" screw with 7/16" X 10 tpi witch is real close to 10mm.

Dave
 
The good news others have add to threads and works .
The mill the casting I am moving the nut still the same length of screw.

View attachment 152479
Sounds like it would work, but will it cause the cross-slide body to overextend? It will need to have an absolute minimum length in which the dovetails overlap. As the cross-slide extends outward, the force against the cutting blade becomes exactly the same as a lever would be, that is, the length of a lever to the fulcrum in relation of the fulcrum to the object being pried against.

What this means is that if the overlap of the dovetails is too short, you are going to have a crash, maybe break your head or your machine.
 
Sounds like it would work, but will it cause the cross-slide body to overextend? It will need to have an absolute minimum length in which the dovetails overlap. As the cross-slide extends outward, the force against the cutting blade becomes exactly the same as a lever would be, that is, the length of a lever to the fulcrum in relation of the fulcrum to the object being pried against.

What this means is that if the overlap of the dovetails is too short, you are going to have a crash, maybe break your head or your machine.
The good news others have did the one inch over run .
I try not to reinvent. The only part I doing is moving the nut instead of milling.

Dave

See casting
https://littlemachineshop.com/products/product_view.php?ProductID=4449
 
The good news others have did the one inch over run .
I try not to reinvent. The only part I doing is moving the nut instead of milling.

Dave

See casting
https://littlemachineshop.com/products/product_view.php?ProductID=4449
Yes, I understand that yo0u are moving the nut. That seems like a good idea. However, I'm not sure it would work in both directions well. Do you have a photo of the slide dissassebled? It isn't a matter of re-inventing, it's a matter of only engineering what's already invented.

BTW, I have indeed invented a new square wheel and am selling them. Would you like one? They work great and give a smooth, fun ride.

With my lathe, I have a similar problem. It has two problems with the slide. The first prob is that it doesn't have slots to mount extra tools on it. The second prob is almost the same as yours. The circle for mounting the slide is too far to the front of the saddle. For 98% of all turning, it is fine, however there is a small percentage in which I need the cross-slide/compound to extend further. It's a real pain. Then when I mount the milling attachment, it becomes quite obvious that the slide needs to go about 3 inches further.
 
Photo of someone else work
You see how he moved the by screws being relocated.

Dave
Cross Feed ScrewAssy W.jpg
 
FYI I just found the photo on a different group.

Dave
 
Off subject
I did get drill chuck to fit right on the lathe
20231227_102233.jpg
 
Yes, I understand that yo0u are moving the nut. That seems like a good idea. However, I'm not sure it would work in both directions well. Do you have a photo of the slide dissassebled? It isn't a matter of re-inventing, it's a matter of only engineering what's already invented.

BTW, I have indeed invented a new square wheel and am selling them. Would you like one? They work great and give a smooth, fun ride.

With my lathe, I have a similar problem. It has two problems with the slide. The first prob is that it doesn't have slots to mount extra tools on it. The second prob is almost the same as yours. The circle for mounting the slide is too far to the front of the saddle. For 98% of all turning, it is fine, however there is a small percentage in which I need the cross-slide/compound to extend further. It's a real pain. Then when I mount the milling attachment, it becomes quite obvious that the slide needs to go about 3 inches further.
Do have a photo of lathe you post and or modle number.

I have a small milling attachment. I am still looking at best to mount to lathe.

Dave
ad photo milling attachment .jpg


Dave
 
Good looking lathe 12" swing.
You use ¾" flat bar and extend the mill out.
I have made new cross slide with great range with new cross feed screw and nut. It was Rockwell 12" lathe it used ½" 10 acme LH thread still tap.

Dave

https://www.grizzly.com/products/grizzly-12-x-36-gunsmithing-lathe-with-stand/g4003g
It's a very nice lathe. I need to check it's levelness again and keep forgetting. I haven't actually used it all that much altho' I have had it for four years (got it just before the price skyrocketed) I highly recommend it, even tho' now, I consider it to be too high priced. I have a 9" Enco which truthfully, I consider to be too small, a kiddies toy--no insult to those of you who have these small lathes, after all a toy lathe is better than no lathe.

In my not so humble opinion, any lathe that one should obtain should have LH thread ability, slow enough speed to make threads comfortably, swing large enough to turn parts larger than one expects when you actuaLly buy it, and other important items. The Enco's slowest speed is 130 RPM, not slow enough for threading under power. The Grizz's slowest speed is 70RPM, would prefer 50 but 70 I can thread easily.

The kiddie toys also have one feature that almost completely kills them for me: the screw on spindle threads. Even when I tightened the set screw on the threaded 3 jaw, when using the reverse function, the would often work it's way off the spindle. As we all know, this could be disasterous. The Grizz has D1-5 Camlock which I consider the very best type of spindle. My only problem with this type of spindle is that the taper is only about 1/2" long which creates problems when one wishes to make replacement back plates. I use the test indicator technique to line up the compound slide for turning that taper. The 1/2", I consider too short to be highly accurate. Maybe it doesn't need to be all that accurate but I prefer these types of interfaces to be highly accurate. (So far I have only made one, not well but a great learning experience.)

My biggest complaint is that the cross slide has no slots which I intend to rectify.
 
It's a very nice lathe. I need to check it's levelness again and keep forgetting. I haven't actually used it all that much altho' I have had it for four years (got it just before the price skyrocketed) I highly recommend it, even tho' now, I consider it to be too high priced. I have a 9" Enco which truthfully, I consider to be too small, a kiddies toy--no insult to those of you who have these small lathes, after all a toy lathe is better than no lathe.

In my not so humble opinion, any lathe that one should obtain should have LH thread ability, slow enough speed to make threads comfortably, swing large enough to turn parts larger than one expects when you actuaLly buy it, and other important items. The Enco's slowest speed is 130 RPM, not slow enough for threading under power. The Grizz's slowest speed is 70RPM, would prefer 50 but 70 I can thread easily.

The kiddie toys also have one feature that almost completely kills them for me: the screw on spindle threads. Even when I tightened the set screw on the threaded 3 jaw, when using the reverse function, the would often work it's way off the spindle. As we all know, this could be disasterous. The Grizz has D1-5 Camlock which I consider the very best type of spindle. My only problem with this type of spindle is that the taper is only about 1/2" long which creates problems when one wishes to make replacement back plates. I use the test indicator technique to line up the compound slide for turning that taper. The 1/2", I consider too short to be highly accurate. Maybe it doesn't need to be all that accurate but I prefer these types of interfaces to be highly accurate. (So far I have only made one, not well but a great learning experience.)

My biggest complaint is that the cross slide has no slots which I intend to rectify.
When I doing production work a tee slots back was vert handy. I could put a cut off tool Or a chamfering tool on back slot. Lock carriage and put welder on lathe and start making parts.

If I was you would make new cross slide with slots. I would use 12L14 it will give great finish and easy like cast iron too

Dave
 
When I doing production work a tee slots back was vert handy. I could put a cut off tool Or a chamfering tool on back slot. Lock carriage and put welder on lathe and start making parts.

If I was you would make new cross slide with slots. I would use 12L14 it will give great finish and easy like cast iron too

Dave
Exactly what I intend. Have the metal but need better milling possibilities before I can start.
 

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