DRO for Samantha Bell!

[steamer]

OK  WRONG>     I forgot to subtract the distance down from the table to the bolt centers...so it should be 2.156 down....drill another hole and I'll take a picture

[propforward]

Hence the wisdom of making the test fixture plate. Nice. 

[steamer]

OK   Nailed it!

Here's the test fixture...keep in mind its at the back of the lathe where I can't see, but there is enough room to get my cordless drill in
The fixture in place with a 3/8 drill sitting in a 3/8 hole in the test fixture.   I pushed the drill in and up against the bed and then traversed the saddle and scribed a line shown in the next photo.

The third photo is taken from the front and shows the fixture in place....I'll repeat the test with the fixture flipped over to the left side of the saddle and seen what I can do behind the headstock.

[steamer]

Now I make some extended drills....like this one   One with a center drill, 1 with a M6 or so tap drill,   I think I can tap the hole with a hand held tap guide block, even blind...

The bushing in the fixture guides these 2 tools to the correct location even blind and backwards......


Dave

[steamer]

OK  so I filpped the jig around , and it works well!    Then I layed it out in Cad....see attached photo 2
You wiill notice that I flip the fixture at each end to gain some distance over and above the actual travel of the Z axis

So now I can cut the scale to 42" down from 45.125", and cover all eventualities!.....

Time to make up some tooling, and clean the shop.   I will also have to take the motor and jack shaft off the back of the lathe to get access to the HS side, but I doh't need to unbolt the lathe from the bench....at least on paper I don't

The scales have leveling screws, and if I want to put a rail underneath the scale for some stiffness, that shouldn't be a problem.

Then the next challenge will be the X axis.    The scale JUST fits so I will need some custom brackets as I've already discussed....and of course I need to do cable routing and hang the actual readout....but I'm getting excited!!!

[steamer]

OK  fixture plate is machined,   tomorrow I'll make up to identical bushings and the extended reach guided tooling and we'll be in business!!!

The other item I'll need to deal with on the cross slide is gib adjusting screw access and cross slide lock.   I see some sxcrew making in my future!.....I may have a geo die with 10-32....I'll look   I can make some square head screws for the gibs so I can get at them with a small wrench.....


Dave

[steamer]

The casting back there is flat, but not vertical, so I'll need to jack one side of the brackets up at mounting.....but we'll sort that out.   The dimension is perfect!   I checked it with the mock up and the bracket and it fits exactly where it needs to go.


Dave

[steamer]

Well   no 1.25" Brass round around, but I do have some Delrin bar.....might make bushing from that,,,,It only has to last for 4 holes....hmmmmm

[steamer]

might be able to get away with some aluminum too....

[Jo]

Its a bit scary drilling holes in our beloved machines 

But its worth it 

Jo

[steamer]

Oh I good with drilling 4 M6 holes in the bed for this benefit!

I found some brass rod, and made up the bushings and the extended body drills were also made up.

I just need a M6 tap... :killcomputer:which will be a 3 or 4 days....Pictures coming...I need to mow the JUNGLE lawn...almost got taken by some predator on the way up the driveway....

[steamer]

The X axis will be a challenge!!!   The scale will cover the gib screws and one of the compound lock screws....so I'll need to make up new ones for sure!    I'm going to look for square head 10-32 screws for the gibs.....that would work for the gibs anyway....I may need to machine a little of the boss that holds the right side compound lock screw to get a square head in there maybe?.....I'll work on that while I wait for the tap to show up..got to mount the DRO box as well, though that already sorted out I think....just need to make the mount and mount it to the bench over the lathe.

Dave

[steamer]

https://www.mcmaster.com/90046A116/


These look interesting!   At least for the gib screws....

[steamer]

Heres the fixture and the drills ...waiting for the retaining compound to cure, and for a tap...

[steamer]

I also ordered the screws to replace what I have on the X axis.   Next is the standoffs to support the scale, and 2 spot faced mounts on the side of the cross slide.....careful like......

....grass to mow.....tomorrow maybe

Dave