Fitting DRO to Boxford model A

[raynerd]

Hi guys, I've got a cheap dro display with 2 glass scales. I've been looking at how to fit them on the boxford and with the very limited space under the carriage, the gib screws and the carriage lock screw, it seems almost impossible to mount it on the side opposite the chuck (even if i used a think scale or magnetic one (which I haven't got anyway!)). I can very very clearly see how to mount it to the chuck side of the carriage or saddle next to the tool post but this will lose me space working up to the chuck. Now I've checked this out and with all my chucks attached, I can still work about 60mm past the chuck (obviously 60mm more than I would need!!) and even with a face place, I'm pretty sure the carriage and tool would easily reach the faceplate work without the dro touching anything. Despite losing this available travel towards the chuck, I can't see how it would even be used anyway.

Has anyone else mounted their dro scale on the chuck side of the saddle?

Chris

[mattinker]

There is no way you can mount it sticking out  behind the cross slide?

Regards, Matthew

[raynerd]

I don't believe there is Matt - certainly no obvious way without countless brackets and the likelihood of me bodging it! I could probably fit a slimline magnetic, but not this glass one. There are the grub screws, limited space and the saddle lock nut. I just can't see a way with the scales I have. I just can't see an issue mounting it chuck side but I'm sure there is based on the fact I haven't seen anyone do it, hence I'm here! The usual issue is that it stops the carriage and tool getting right up to the spindle head but mine still will!!

[BillTodd]

Not a great idea to mount a scale near the chuck - for obvious reasons.

Have you seen Doubleboost's videos about fitting a dro to his Harrison? They might give you some ideas

Years ago, I fitted a pair of cheap calliper scales to my Southbend , but they were a lot smaller than typical glass scales.

These are the best pictures I can find 

[Jonny]

X axis easy on rear side and will have to fabricate brackets, best done any way.

Y axis can be problematic for usability, often over looked even by the pros.
Would you really want something in the way, logic prevails.
If mount chuck side think about facing off, chuck may hit, certainly larger jobs.
On the other hand not fond of opposite side, tailstock interference and extended distance before starting the task with reduced travel.
Bright side looks like can attach out board with some bracing and specific bracketry, that's the only realistic way to do the earlier Harrisons, new ones easy with magnetic.

Have you the C type covers?
Do these glass scales screw on to a backing, easiest just need shims to align.

Whatever you do note the routing of the cables, again don't want anything in the way or interfering.

[raynerd]

Thanks for all the help guys, this really is a headache!! Billtodd - your image is identical to my setup but there is no way I could fit the glas scale under the slide - just no room!! I really really do believe for the small scale work I do, I'll actually get more disruption interfering with the reach of the tail stock if I mount it rear side, that I would have issues with the chuck in the chuck side. That said, something cries out to me that chuck side is just wrong. More thinking is required.....

[Jonny]

First picky of Bills attach one end of glass scale along where its down to bare metal with two tapped holes. Can go further in so tailstock clears, nothing lost. If scales a one piece no backing with just elongated holes at each end will need to mount that to a support going outboard and in turn to cross slide. Will need bracing up.

L shaped bracket to mount the reader head off that raised lug just below. Check travel may have to mount further out.

Magnetic would have gone under an 11"/140 bolt on cross slide cover, unfortunately not available when had one.

Done this 5 years ago on current.
My reader head mounted outboard at rear covered over with aluminium plate that serves to brace up from swarf build up. http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING003.jpg
http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING006.jpg
Where tailstock hits I lose approx. 7mm, to clear a glass scale that are much larger you would mount further away over chip tray and brace to the next raised lug on rear carriage above adjusting strip.
Easy when know how and not half as bad as it looks, why on earth no one elses done it.

Cabling run towards tailstock where it will bunch up then all the way back over top of glass scale. This way swarf build up wont snag and make easier to get your hands in to clear debris.
http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING002.jpg
http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING001.jpg

[raynerd]

Great photos Jonny - thank you for posting.