The Home Machinist!

OK, to indicate the carriage travel on the lathe, I have been using a Mighty Mag base and an imported 2" travel dial indicator. Up until now things have gone well, not great but well. The problem on my lathe is that the best location to mount the Mighty Mag and dial indicator results in the lathe dumping nice hot chips on the dial. The dial cover is 1 mm clear plastic and is now very difficult to view due to the hot chips melting the plastic. The cover has also lost it's convexity and is now impinging on the dial's needle causing the needle to bind and then jump ahead.

1) How do most folks without DRO's indicate the carriage travel? A decent 2" travel dial indicator that could substitute will cost from $322 to $489 and now that would be getting into the DRO Pros cost category.

2) Do any of the indicators come with glass crystals instead of plastic? If anyone has a photo of their setup that would be really appreciated. Thanks,

Harper

I'm a great believer in reading every old machinist book I can find Harper. Well before todays modern DRO's were even thought of a way to speed up slide movements, increase accuracy because of lead / lag errors in new or worn feed screws, and lessen miscounting errors while using the machines dials was needed for jig borers. Moore Tools and I'd assume a few other jig borer manufacturers started using very accuate 1" travel indicators and an accessory kit of distance rods in 1" increments. Those distance rods can still sometimes be found on places like Ebay and few recognise them for what they are. Moore went so far as having an area cast into the machines during that period so those indicators could be mounted and aligned with the slides and were better protected. They also used a special rubber cap with glass friction fit in those caps to protect the indicator and its face from chips and coolant. In use the parts edge was found, the indicator zeroed, then for less than an inch of travel the indicator was used. For more travel then those distance rods were used along with the indicator. Machining out something like an aluminum case with a glass face and a cutout in the side for zeroing the indicator would work to protect any indicator. It could even be bed mounted much like a travel stop. Micrometer setting rods could replace those distance rods as long as an area in front of the indicators plunger such as a V way was cut and the same attached onto the carriage so the setting rod was kept true to the machines travel would give you a very accurate method on the longitudinal moves. Slower than a proper dro, but certainly more accurate than the cheap Chinese digital scales you see some using. The ideas an old one but doesn't seem to be that well known that it was used to do some extremely accurate work.

The 2" travel indicators are handy but they take up a lot of room at each end of the indicator. Only my personal opinion, but the 1" indicators and using those mike setting rods gives you something that takes up much less room and multiple inches of accurate measurement depending on how many of those setting rods you have, but there also available seperately. Starret and Mitutoyo and I guess others list them. I was going to use the idea on my mill and even bought the setting rods up to 12" before I then decided on a proper DRO.

Picture tomorrow.

1) Build something that look like a carriage stop, but arranged to hold the indicator by the fixed shaft. Mount it on the right side of the carriage, never seen any chips in that area.
2) You own a lathe. Make a ring with a glass top to plop over the indicator.
3) You need to replace the lens because is now rubbing the hand(s). Replace it with glass. Google "glass discs"

tornitore45 wrote: ↑Tue Feb 27, 2018 10:34 am 1) Build something that look like a carriage stop, but arranged to hold the indicator by the fixed shaft. Mount it on the right side of the carriage, never seen any chips in that area.
2) You own a lathe. Make a ring with a glass top to plop over the indicator.
3) You need to replace the lens because is now rubbing the hand(s). Replace it with glass. Google "glass discs"

This triggered a brainstorm: a carriage stop that consists of a rod attached to the right side of the carriage and running through a bushing mounted on a movable stop. Collars on the rod set stops in both directions. Loosening the movable stop permits normal full-range operation without needing to remove anything.

Building on John Hasler idea... precision relative motion can be set by inserting gauge block between the stop and the collar.
Remove the block and move left a calibrated distance.

1) How do most folks without DRO's indicate the carriage travel? A decent 2" travel dial indicator that could substitute will cost from $322 to $489 and now that would be getting into the DRO Pros cost category.

You can buy a 2" indicator for under $30
https://www.amazon.com/Space-Indictor-T ... +indicator

Here is the promised picture, this was originally cast from Aluminum for a 14 1/2" South Bend lathe. I now have a Clausing Colchester and adapted it to that. As long as material is left I can keep on changing it. There is a swing up plexiglas cover over it. That is what the hinge is to. The original only lasted about 20 years and I don't want to buy another one too often.

I use a dial indicator mounted on a magnetic base. The base sits on the left side of the carriage and contacts a stop I attached to the front of the headstock. It only has 1" of travel, but so far it works great. "Poor man's DRO"

My Rockwell came to me with a shop made indicator mount. Basically a block mounted on the headstock with a bore aligned with the near side of the saddle. In that block bore was a 1"(?) dia bar maybe 14" long with detents every 1". And there was a spring loaded ball bearing in the top of the block under a spring, under a knurled knob to adjust pressure (by hand) on ball in the detent, or to lock it hard. The end was machined for mounting a dial indicator. Using that with a 1" DI, you could get very good incremental measurements suitable for most of my longitudinal location needs. By adding an adjustable micrometer barrel in place of the DI, you could also use it for a stop (or multiple).

I have my 2 inch DI to the left of the carriage mounted on a carriage stop type clamp. The length of the 2"DI is such that the dial ends up shielded from the chips by the headstock. I only hook it up when I need it but the dial stays clean. I don't like anything to the right of the carriage because if I want to run the carriage away from the chuck to check a thread fit or whatever the DI would be in the way.

After pricing long travel indicators for my Heavy 10, I just bought one of these.

https://www.aliexpress.com/item/Free-sh ... 0.0.PhPJNJ

No complaints.