Mounting indicator on Logan 820

tmenyc

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For the Logan 200 and 800 series owners: what have you done about mounting indicators?
I'm trying to set up a simple arrangement of zero'ing on a shoulder very close to the chuck, and there is just no real estate to mount an indicator facing the incoming carriage, and using the chuck-facing side of the carriage as the indicated body. The quick change gearbox is solidly in the way for the 800 owners. In theory there are 5" from the right side of the quick change gearbox housing to the left side of the carriage at the point that I would definitely want to stop the carriage before hitting the chuck. And, there are 4" of the front V ways available under the headstock housing that could certainly hold a low-profile ways mount if such a thing exists. The photo shows the available real estate.

I'm already using one the 3D printed QCTP dial indicator holders (my wife printed it for me...nothing like an aiding and abetting spouse...), but that doesn't operate while I have a tool in the QCTP. I can't seem to find a ways-mounted holder like it on Thingiverse, where there are numerous QCTP indicator holder plans.

Real estate is well-known to be scarce for Logan owners, since the compound top is sloped, so not available for a magnet mount.
How have you managed this?

Many thanks,
Tim
 

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Not a direct answer to your question but Logan made a micrometer carriage stop # AC-234. (LP-1626) This clamped to the front "V" way. I have no idea if it is still available. "mrpete222" and "Toms Techniques" on Youtube have done examples of micrometer carriage stops for lathes.

This is the best image I could find of the Logan AC-234:


LoganAC234.PNG
 
Thanks, I'll research it! That would certainly work, and I could add an indicator to it.

Tim
 
You could 3D print one that clamped on the ways (like the one Clueless shows) if you have that method open to you.

These are a couple I cast in urethane (before the 3D printing thing took off) for my Atlas. They work fine even though they're not metal -- doesn't take a lot of force to lock an indicator in place.

-frank

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On my Logan, I decided to mount the indicator to the right of the carriage. Of course, that
means the carriage moves away from the indicator, but I just "preload" the indicator by the amount
I need and then zero the needle. The advantage is it's out of the way, there's plenty of room for it, and it doesn't get covered
in oil and chips.

To do it, I modified my carriage stop by making a large squared headed "bolt" that replaces the existing
bolt in the stop. Since it's cross drilled, I can bolt the indicator to the stop and line it up with a tab bolted
to the carriage. The funny looking extension is only there to provide clearance for the Kipp handle that acts
as my carriage lock. With a piece of hex stock on the other side, it still works as a carriage stop when I need one.
 
Frank, I’m completely fine with printing 3D, but can’t design the file. (There’s just barely enough time in my life to climb the machining learning curve...can’t fit another long slope in there right now. Do you know of an existing file that I could download?

NGB, that’s really interesting, and perhaps achievable, too! I love the idea that it uses the space to the right of the carriage, where there is real space.

Thanks to both of you.
Tim
 
Hey Tim, no I'm sorry I don't. And I don't have the gear and where with all to come up with one either. You never know though, someone else might see this who has and may pipe up. Hard to imagine this hasn't occurred to someone else already!

-frank
 
I've got one of those carriage stops on my larger Logan, but it does not work well for an indicator mount - there isn't much clearance between the top and the spindle housing. Best measure that area before doing an Ebay hunt for one.

I use a Mighty Mag indicator base right on the ways, if I'm not using the stop, or on the Quick Change gearbox otherwise. A short arm can be sawn from 3/8" drill rod so it doesn't poke out from the lathe too much, then a snug with a standard arm + indicator attached to it.

The supercheap alternative is to just pick up a piece of 1/4" steel at the hardware store, then bolt or clamp it to the bench, and put the indicator stand on that. When I was just using a benchtop lathe, I cut some 4"x8" plates in half and made 4"x4" bases for the magnetic indicator mounts. Heavy enough to keep them from moving too much, good magnetic attachment. Vibration from the lathe might make anything mounted to the bench too unreliable for your liking but it's cheap and easy enough to be worth a try.
 
Thanks! I thought about that last night, but of course that foot or so where the clamp and steel would be is exactly where I need to stand, although I may fiddle more with the concept. There is really no space between carriage and gearbox housing, except on the way itself. Lots of space right of the carriage.
Tim
 
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