Hi, what are the chances that everything will stay in alignment without pins holding the rails and trucks in place? maybe an easy fix would be to add Loctite 638 adhesive to those parts. this looks like a good idea. Rich
That is a great question and I replied to a similar question previously but I cannot find it right now. I did some calculations regarding the frictional force of the rails and it looked as if there would be no problem, if there is then I have increasing levels of improvement in mind. The first is as you suggest using Loctite under the rails. If that was not sufficient I would attempt drilling the rails to fit tapered dowel pins. If drilling and reaming the rails proved to be lacking in fun then I would make some precise fitting blocks between the rails and the machined off dovetails to take the lateral force. Thanks for highlighting this potential problem.
Sorry to say that I have only just found your channel recently Tony. I'm in the process of doing a mini refurb on my new to me lathe at the moment, but don't think I will going as far as you have. I still have my original copy of your book that I bought about the same time as I got my Harris Magnum II on the road. It's being rebuilt ready to take to the TT this year, which is the 40th aniversary of its first visit. I never did get to put any of your wisdom into practice, marriage, family, kids, work, all got in the way. Now I'm retired, maybe I should have another go.
You need the latest book - motochassis.com . Yes, have another go, never slow down, retirement is wasted if you ease up. Have you seen the lathe playlist ua-cam.com/video/waKfJA1Wic8/v-deo.html&pp=gAQBiAQB
The control input was the only feature that was changed from the original. It went through 3 iterations, the final being the 16 key numpad. I'll make sure that I show that when the cam grinding trials begin, thanks.
I read your reply about pinning and it would make more sense to me to pin the rails so that when you take them off and clean they would go back in play without having to do the alignment tasks each and every time. Pinning would not only insure stability under load or overload during machining but also assembly repeatability. It would seem to be a simple job putting 2 pins in each rail. Your thoughts? Unless you never plan on taking the rails off.
You have it in your last sentence. Unless I have a problem I do not expect to be taking them off. I am looking at them in the same light as the dovetails which you do not take off for maintenance. If they wear then they have to come off but they will be replaced by new ones which would need new locating holes. I do not anticipate any misalignment in normal use and I would prefer that there was some movement to cushion any heavy impacts. Real experience will dictate my future actions. The trucks are a different matter, they come off easily, you can buy oversize balls to take up wear and even buy new trucks off the shelf.
I was to make the same comment. It would be wise to do so. And also stamp L on the front face of the left rail and R for the right one. Fool proofing idea...
Wouldn't "indicator sag" throw off your measurement when you rotate the indicator? I did something similar however I mounted a test indicator to the top of the head stock. What I did was mount a ground parallel in the chuck and while keeping the indicator stationary I rotated the chuck and adjusted the parallel until it was aligned with the spindle. I then attached the test indicator to the truck while mounted on the rail and swept it to the parallel.
There are things which make this a non-issue. Firstly the indicator is very rigidly mounted and secondly any sag would be near right angles to the direction of stylus movement and so its effect would be greatly reduced. It sounds like you have do a similar modification?
@@MotoChassisByTonyFoale Yes, I converted the cross slide to linear rails on a 9x20 lathe that was converted to cnc. It turned out better than I expected and holds tolerances quite well.
Hi Tony, I believe that the lathes are made to face slighty concave , ( to machine deeper towards the centre to make sure that the parts turned bear on the outside, ...
Concave is certainly preferable to convex, but I prefer to get as close as possible to dead flat and chose myself whether the application needs the centre to be relieved.
The amount of acceptable concavity is tiny. Its purpose is to ensure that a turned part sits on a surface plate without any chance of a wobble. If you never have a need for checking a part on a flat datum surface like this then flat facing it fine.
@@martinconnelly1473 Thanks for that. Whenever I have a need where lack of wobble is important I always relieve an appropriate part of the centre. I prefer this to be under my control because sometimes I want to make things as flat as possible. In any case with my software for the lathe control I only have to specify a slope and it will face with any degree of concavity of convexity that I want.
Hi, what are the chances that everything will stay in alignment without pins holding the rails and trucks in place? maybe an easy fix would be to add Loctite 638 adhesive to those parts.
this looks like a good idea.
Rich
That is a great question and I replied to a similar question previously but I cannot find it right now. I did some calculations regarding the frictional force of the rails and it looked as if there would be no problem, if there is then I have increasing levels of improvement in mind. The first is as you suggest using Loctite under the rails. If that was not sufficient I would attempt drilling the rails to fit tapered dowel pins. If drilling and reaming the rails proved to be lacking in fun then I would make some precise fitting blocks between the rails and the machined off dovetails to take the lateral force. Thanks for highlighting this potential problem.
Very interested to see how it will perform. Great work.
You and me both! Sunday will see a video doing some tests.
Sir, the alignment portion of the video was helpful in setting up my homemade mill/lathe. Thank you. Bob from.Canada
So glad to hear that the video was of help to you. Comments like that highlights why I do the videos. Thank you.
Looks great. Thanks for the video Tony. I look forward to seeing swarf 😊
There will be swarf two or three videos down the line.
Sorry to say that I have only just found your channel recently Tony. I'm in the process of doing a mini refurb on my new to me lathe at the moment, but don't think I will going as far as you have.
I still have my original copy of your book that I bought about the same time as I got my Harris Magnum II on the road. It's being rebuilt ready to take to the TT this year, which is the 40th aniversary of its first visit. I never did get to put any of your wisdom into practice, marriage, family, kids, work, all got in the way. Now I'm retired, maybe I should have another go.
You need the latest book - motochassis.com . Yes, have another go, never slow down, retirement is wasted if you ease up. Have you seen the lathe playlist ua-cam.com/video/waKfJA1Wic8/v-deo.html&pp=gAQBiAQB
Hi Tony, looks great, when doing some machining show ELS panel, is it with 16 key pad or 10 push buttons, looking forward to Sunday. Thanks.
The control input was the only feature that was changed from the original. It went through 3 iterations, the final being the 16 key numpad. I'll make sure that I show that when the cam grinding trials begin, thanks.
I read your reply about pinning and it would make more sense to me to pin the rails so that when you take them off and clean they would go back in play without having to do the alignment tasks each and every time. Pinning would not only insure stability under load or overload during machining but also assembly repeatability. It would seem to be a simple job putting 2 pins in each rail. Your thoughts? Unless you never plan on taking the rails off.
You have it in your last sentence. Unless I have a problem I do not expect to be taking them off. I am looking at them in the same light as the dovetails which you do not take off for maintenance. If they wear then they have to come off but they will be replaced by new ones which would need new locating holes. I do not anticipate any misalignment in normal use and I would prefer that there was some movement to cushion any heavy impacts. Real experience will dictate my future actions. The trucks are a different matter, they come off easily, you can buy oversize balls to take up wear and even buy new trucks off the shelf.
Hi, Tony. Now everything is carefully aligned, will you add dowel pins to preserve said alignment? ⭐🙂👍
I was to make the same comment. It would be wise to do so. And also stamp L on the front face of the left rail and R for the right one. Fool proofing idea...
This has been asked a few times. Have a look at my reply to richb419's comment which is pinned at the top of the comments list.
Wouldn't "indicator sag" throw off your measurement when you rotate the indicator? I did something similar however I mounted a test indicator to the top of the head stock. What I did was mount a ground parallel in the chuck and while keeping the indicator stationary I rotated the chuck and adjusted the parallel until it was aligned with the spindle. I then attached the test indicator to the truck while mounted on the rail and swept it to the parallel.
There are things which make this a non-issue. Firstly the indicator is very rigidly mounted and secondly any sag would be near right angles to the direction of stylus movement and so its effect would be greatly reduced.
It sounds like you have do a similar modification?
@@MotoChassisByTonyFoale Yes, I converted the cross slide to linear rails on a 9x20 lathe that was converted to cnc. It turned out better than I expected and holds tolerances quite well.
Hi Tony, I believe that the lathes are made to face slighty concave , ( to machine deeper towards the centre to make sure that the parts turned bear on the outside, ...
Concave is certainly preferable to convex, but I prefer to get as close as possible to dead flat and chose myself whether the application needs the centre to be relieved.
The amount of acceptable concavity is tiny. Its purpose is to ensure that a turned part sits on a surface plate without any chance of a wobble. If you never have a need for checking a part on a flat datum surface like this then flat facing it fine.
@@martinconnelly1473 Thanks for that. Whenever I have a need where lack of wobble is important I always relieve an appropriate part of the centre. I prefer this to be under my control because sometimes I want to make things as flat as possible. In any case with my software for the lathe control I only have to specify a slope and it will face with any degree of concavity of convexity that I want.
I could be wrong but I don't think the rails will stand the test of time...
Time will tell. These rails are used on CNC machines. My fingers are crossed tightly.
Your methods are severely flawed.
I think it looks reasonable. Similar to trimming a mill. How would you approach this @ jasonhall3729?
@@iancoulston6452 simply, I wouldn't lol