MWF FEED
10th February 2022, 07:50 PM
I decided a while ago that I was going to fit an X, Z DRO to my lathe. So I looked for what information I could, (which proved to be limited), sourced the components I needed, (which turned out to be wrong!), and then left everything lying around for a while as more important things came up. Hopefully, by sharing my experience I can save someone from wasting time and money and offer an insight if they decide to fit their own.
Firstly, the linear scales. When I looked to buy these the seller showed a table for all the different lengths and their associated fitting dimensions and operating parameters. I managed to get my order completely wrong by reading off the sellers specifications! Either the information was wrong or inadequate, or it was just me rushing in to things! Anyway, I think wherever you decide to buy scales from will have the same sort of information so here is a picture which hopefully explains things a little clearer, (sorry about the picture but the perspective of the lines moved as the picture was taken).
Attachment 396741 (https://metalworkforums.com/attachment.php?attachmentid=396741)
Dimensions A and B are pretty straightforward with A being the overall length of the scale and B being the distance between the two mounting holes.
Dimension D is the travel limit of the length of the reader, (the actual reader having a buffer on each end).
Now, dimension E is the one that caught me out! As you can see in the picture the left datum line of E is in the centre of the reader. If you push the reader over to the right of the scale so the buffer aligns with the right hand limit of the scale, then the right hand datum line of dimension E is where the the centre of the reader will be. So, the actual readable distance, E, is quite small in relation to the length of the scale. Does that make as much sense to someone reading it as it does to me writing it?!
Suffice to say I ordered two scales which were totally wrong for my needs!
So, I recalculated my needs, (properly this time), and ordered two more scales.
Now I don't know if all scales/kits come with absolutely no instructions but it was certainly true of mine! The scales themselves come with some mounting hardware and a length of guarding appropriate for the scale. I also wasn't aware of whether there was a right or wrong way to mount the scales but I chose to hard mount the reader and then mount the scale on the moving part of the lathe. This method was chosen as there were already various, unused, tapped holes in strategic places which suited this type of mounting. It also served the purpose of having the open travel slot of the scale on the underside which would better prevent waste from fouling the scale.
Pictures are worth a thousand words they say so I will put the pictures together of the mounting for the Z axis and then group the pictures for the X axis seperately. I made up two sets of bespoke mountings for the two scales and like I said, I made them to fit holes which were already in the lathe, (mostly).
Just a couple of points to look out for when installing this. I made sure I put a spacer shim on top of the length of angle I used as the main support before I secured everything up, this ensured that once the shim was removed, there was some clearance between the top of the angle and the underside of the cross slide. I also leveled the angled bracket I made with a spirit level so it matched the bed. Also, sounds obvious to me now but make sure you have clearance for the mounting bracket at each end of its travel. (sorry but I changed my idea of how was going to mount it so picture 5 is not what I ended up with).
Attachment 396742 (https://metalworkforums.com/attachment.php?attachmentid=396742)Attachment 396743 (https://metalworkforums.com/attachment.php?attachmentid=396743)Attachment 396744 (https://metalworkforums.com/attachment.php?attachmentid=396744)Attachment 396745 (https://metalworkforums.com/attachment.php?attachmentid=396745)Attachment 396746 (https://metalworkforums.com/attachment.php?attachmentid=396746)Attachment 396747 (https://metalworkforums.com/attachment.php?attachmentid=396747)Attachment 396748 (https://metalworkforums.com/attachment.php?attachmentid=396748)Attachment 396749 (https://metalworkforums.com/attachment.php?attachmentid=396749)Attachment 396750 (https://metalworkforums.com/attachment.php?attachmentid=396750)Attachment 396751 (https://metalworkforums.com/attachment.php?attachmentid=396751)Attachment 396753 (https://metalworkforums.com/attachment.php?attachmentid=396753)Attachment 396754 (https://metalworkforums.com/attachment.php?attachmentid=396754)
Attachment 396755 (https://metalworkforums.com/attachment.php?attachmentid=396755)
The X axis was probably the harder of the two to fit up, mainly because of the restricted space to work in and the lack of access to the mounting holes. Again I chose to solid mount the reader and have the scale moving above it. The cross slide had no suitable mounting points in it for the reader so I had to drill and tap two holes, then put some spacer washers between the reader and the cross slide bed so it matched up to the scale when that was mounted above it. Mounting the scale where I chose to does mean the compound is compromised. I set the compound at 45 degrees and will have to work around that later if I find I need to move too far off that setting. To mount the scale I made up two individual mounting brackets, one for each end of the scale. One bracket was a sort of extended angle bracket with a threaded hole for the scale to screw to but the other end was more of a problem. I ended up with a bracket that trapped the end of the scale and then extended to where a suitable mounting could be accessed. Again I put some spacer washers between the cross slide and the base to allow some clearance between the two.
Attachment 396756 (https://metalworkforums.com/attachment.php?attachmentid=396756)Attachment 396758 (https://metalworkforums.com/attachment.php?attachmentid=396758)Attachment 396759 (https://metalworkforums.com/attachment.php?attachmentid=396759)Attachment 396761 (https://metalworkforums.com/attachment.php?attachmentid=396761)
Attachment 396763 (https://metalworkforums.com/attachment.php?attachmentid=396763)IMG_20220127_134300.jpg (https://metalworkforums.com/attachment.php?attachmentid=396764&d=1644473420)IMG_20210318_094224.jpg (https://metalworkforums.com/attachment.php?attachmentid=396765&d=1644473490)
So, I eventually got everything secured on the lathe. The whole set for the monitor and the two correct scales was less than $300 from Banggood, (the only problem I experienced was with their choice of courier who decided they would not deliver to my address even though the postage was calculated for my address at checkout. I ended up having to go to their depot to pick things up). Accuracy is 2-3% which is ample for taking quick, measured cuts though I will probably carry out final cut adjustments using a dial gauge. I hope this helps anyone out there who is thinking about having a go at fitting one of these and if there is anything I've missed or not explained clearly enough, drop me a message and if I can help out I will.
Just have to work where I'm going to mount the monitor now!
Attached Images
https://metalworkforums.com/images/attach/jpg.gif IMG_20220127_134300.jpg (https://metalworkforums.com/attachment.php?attachmentid=396764&d=1644473420) (266.4 KB)
https://metalworkforums.com/images/attach/jpg.gif IMG_20210318_094224.jpg (https://metalworkforums.com/attachment.php?attachmentid=396765&d=1644473490) (262.5 KB)
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=207739&goto=newpost)
Firstly, the linear scales. When I looked to buy these the seller showed a table for all the different lengths and their associated fitting dimensions and operating parameters. I managed to get my order completely wrong by reading off the sellers specifications! Either the information was wrong or inadequate, or it was just me rushing in to things! Anyway, I think wherever you decide to buy scales from will have the same sort of information so here is a picture which hopefully explains things a little clearer, (sorry about the picture but the perspective of the lines moved as the picture was taken).
Attachment 396741 (https://metalworkforums.com/attachment.php?attachmentid=396741)
Dimensions A and B are pretty straightforward with A being the overall length of the scale and B being the distance between the two mounting holes.
Dimension D is the travel limit of the length of the reader, (the actual reader having a buffer on each end).
Now, dimension E is the one that caught me out! As you can see in the picture the left datum line of E is in the centre of the reader. If you push the reader over to the right of the scale so the buffer aligns with the right hand limit of the scale, then the right hand datum line of dimension E is where the the centre of the reader will be. So, the actual readable distance, E, is quite small in relation to the length of the scale. Does that make as much sense to someone reading it as it does to me writing it?!
Suffice to say I ordered two scales which were totally wrong for my needs!
So, I recalculated my needs, (properly this time), and ordered two more scales.
Now I don't know if all scales/kits come with absolutely no instructions but it was certainly true of mine! The scales themselves come with some mounting hardware and a length of guarding appropriate for the scale. I also wasn't aware of whether there was a right or wrong way to mount the scales but I chose to hard mount the reader and then mount the scale on the moving part of the lathe. This method was chosen as there were already various, unused, tapped holes in strategic places which suited this type of mounting. It also served the purpose of having the open travel slot of the scale on the underside which would better prevent waste from fouling the scale.
Pictures are worth a thousand words they say so I will put the pictures together of the mounting for the Z axis and then group the pictures for the X axis seperately. I made up two sets of bespoke mountings for the two scales and like I said, I made them to fit holes which were already in the lathe, (mostly).
Just a couple of points to look out for when installing this. I made sure I put a spacer shim on top of the length of angle I used as the main support before I secured everything up, this ensured that once the shim was removed, there was some clearance between the top of the angle and the underside of the cross slide. I also leveled the angled bracket I made with a spirit level so it matched the bed. Also, sounds obvious to me now but make sure you have clearance for the mounting bracket at each end of its travel. (sorry but I changed my idea of how was going to mount it so picture 5 is not what I ended up with).
Attachment 396742 (https://metalworkforums.com/attachment.php?attachmentid=396742)Attachment 396743 (https://metalworkforums.com/attachment.php?attachmentid=396743)Attachment 396744 (https://metalworkforums.com/attachment.php?attachmentid=396744)Attachment 396745 (https://metalworkforums.com/attachment.php?attachmentid=396745)Attachment 396746 (https://metalworkforums.com/attachment.php?attachmentid=396746)Attachment 396747 (https://metalworkforums.com/attachment.php?attachmentid=396747)Attachment 396748 (https://metalworkforums.com/attachment.php?attachmentid=396748)Attachment 396749 (https://metalworkforums.com/attachment.php?attachmentid=396749)Attachment 396750 (https://metalworkforums.com/attachment.php?attachmentid=396750)Attachment 396751 (https://metalworkforums.com/attachment.php?attachmentid=396751)Attachment 396753 (https://metalworkforums.com/attachment.php?attachmentid=396753)Attachment 396754 (https://metalworkforums.com/attachment.php?attachmentid=396754)
Attachment 396755 (https://metalworkforums.com/attachment.php?attachmentid=396755)
The X axis was probably the harder of the two to fit up, mainly because of the restricted space to work in and the lack of access to the mounting holes. Again I chose to solid mount the reader and have the scale moving above it. The cross slide had no suitable mounting points in it for the reader so I had to drill and tap two holes, then put some spacer washers between the reader and the cross slide bed so it matched up to the scale when that was mounted above it. Mounting the scale where I chose to does mean the compound is compromised. I set the compound at 45 degrees and will have to work around that later if I find I need to move too far off that setting. To mount the scale I made up two individual mounting brackets, one for each end of the scale. One bracket was a sort of extended angle bracket with a threaded hole for the scale to screw to but the other end was more of a problem. I ended up with a bracket that trapped the end of the scale and then extended to where a suitable mounting could be accessed. Again I put some spacer washers between the cross slide and the base to allow some clearance between the two.
Attachment 396756 (https://metalworkforums.com/attachment.php?attachmentid=396756)Attachment 396758 (https://metalworkforums.com/attachment.php?attachmentid=396758)Attachment 396759 (https://metalworkforums.com/attachment.php?attachmentid=396759)Attachment 396761 (https://metalworkforums.com/attachment.php?attachmentid=396761)
Attachment 396763 (https://metalworkforums.com/attachment.php?attachmentid=396763)IMG_20220127_134300.jpg (https://metalworkforums.com/attachment.php?attachmentid=396764&d=1644473420)IMG_20210318_094224.jpg (https://metalworkforums.com/attachment.php?attachmentid=396765&d=1644473490)
So, I eventually got everything secured on the lathe. The whole set for the monitor and the two correct scales was less than $300 from Banggood, (the only problem I experienced was with their choice of courier who decided they would not deliver to my address even though the postage was calculated for my address at checkout. I ended up having to go to their depot to pick things up). Accuracy is 2-3% which is ample for taking quick, measured cuts though I will probably carry out final cut adjustments using a dial gauge. I hope this helps anyone out there who is thinking about having a go at fitting one of these and if there is anything I've missed or not explained clearly enough, drop me a message and if I can help out I will.
Just have to work where I'm going to mount the monitor now!
Attached Images
https://metalworkforums.com/images/attach/jpg.gif IMG_20220127_134300.jpg (https://metalworkforums.com/attachment.php?attachmentid=396764&d=1644473420) (266.4 KB)
https://metalworkforums.com/images/attach/jpg.gif IMG_20210318_094224.jpg (https://metalworkforums.com/attachment.php?attachmentid=396765&d=1644473490) (262.5 KB)
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=207739&goto=newpost)