Test Dial Indicator Service

[chris mabbott]

I started this a couple of weeks ago but I’ve been a bit too busy to complete it. I meant to post it earlier but I’m late 🙄

I picked this up a while ago and it never worked quite right, it was sticky, the needle didn’t return to the same spot, so I kinda put it on the back shelf..

What follows are the disassembly photos only, I hadn’t been able to find any info on how to service these, so hopefully this will help others in the same predicament….

First I took a series of reminder shots of how it looked prior to taking it apart..

[chris mabbott]

2

[chris mabbott]

First step, remove the wiggler arm.. then the rotating glass bezel. the bezel is a snap fit on this model, I think they’re all pretty much the same.

[chris mabbott]

I used a watch hand puller to remove the sweep hand, then the dial lifts of..

Once the dial was removed, I could see what part of the problem was, the brass hairspring was twisted and deformed 😮

[chris mabbott]

The brass plate is simply a jeweled support for the gear pivot, this is removed via the two screws, be careful to remove it straight out and not to bend the pivots.. You can see the dirty gunky oil and grease on the reverse. Looks like someone used our best friend, WD40 or as I call it WDF 40 😆

Once it has been removed, we are faced with the main plate, also held in place by two weird screws. None of my philips screwdriver tips fit these and I have a set of 20, so I ended up using a flat that fit one of the slots..

[chris mabbott]

Once the inner bezel is off, you can remove the main gear..

There is also a direction lever inside, this has a spring attached to it and looks to be a real SOB to replace, so I chose to leave it be, I can clean this as is while the rest of the parts go into the cleaning solution..

That’s basically it for the disassembly, the fun part will come when I try to put it back together
The hairspring looks like an alarm clock type, I/m wondering if anyone can add anything on this, would an alarm HS work on this??

[namonllor1953]

My brother from another mother, you never cease to amaze me dude!!! I love it!!
Others would go out and just buy another, “nooOooo not you, Pikachu knows everything”. Instead you say what I would say, “can’t break it anymore, what the …… let’s see how it’s done.
I hope you do the reassembly because you’re right, there is NO, none, nada, zilcho, goose egg, niet info on the inner workings of dial indicators, On the other hand I’ve had mine over 20 years and it still works like new. Sttarrett Last Word Indicator…best there is!
Thanks for sharing this info and yes, this too should be pinned and locked as a permanent information post.
Felicidades hermano,

[Bob Tascione]

Hey Chris,
Nice demo.
You might have some luck getting that hairspring from Long Island Indicator Service. They have a good supply of parts for the older 503-100 series. I’ve used them in the past to service my Interapid and Brown & Sharpe and have also purchased dial parts from them for an older Mitutoyo. I broke my Interapid again so looks like I’ll be using them again soon! They do good work.
Good luck,
Bob

[chris mabbott]

Hey Ren,

the secret to any job is having a few good work tunes to get the foot tappin and the head a boppin
so here’s a starter <span style=”color: #BF0000″>REPAIR TUNE</span>

OK I decided to get this thing back together. I will mention that I did get this with a bunch of stuff and I think it’s an old, well used model that sat in a box for a while, so i’ll put it down to lack of use and dirt, also the messed up spring WHICH, surprisingly, I managed to straighten 😯 It seems to work fine after my tweezer job..

[chris mabbott]

I should have mentioned that this has 4 jewels, they were good, and the two tiny carrier roller bearings on the wiggler were also good after the clean and oiling, CUUTE 😆

I learned that replacing the main gear, then applying oil into the jewels worked better than lubing the pivots first. you can also set up the mesh easier than with the dial together…

[chris mabbott]

I didn’t apply any oil on the rack and pinion, no need as it’s alloy on steel, the movement was nice and smooth now after cleaning.
You can also set up the amount of tension by adjusting the set screws, I think this is how it’s calibrated.

Anyhow, it’s back together and seems to be returning fine to zero. I’ll have to compare it with my other known good one, but a lot better than what it was…

[chris mabbott]

@Bob Tascione wrote:

Hey Chris,
Nice demo.
You might have some luck getting that hairspring from Long Island Indicator Service. They have a good supply of parts for the older 503-100 series. I’ve used them in the past to service my Interapid and Brown & Sharpe and have also purchased dial parts from them for an older Mitutoyo. I broke my Interapid again so looks like I’ll be using them again soon! They do good work.
Good luck,
Bob

Bob we muat have been posting at the same time…Thanks for the company name, I’ll definitely add that to my black book.

[Bob Tascione]

Great job on that hairspring Chris. It looked hopeless from your pic!
Buen trabajo y como dijo Ren Felicidades!
Adios,
Bob

[namonllor1953]

I’ve got to second Bob’s observation and say great job on that mainspring. By the way it looked in the first photo, it looked like a hopeless mess of bird-nest material. Look at it now…wow!!
Great choice in tunes too, it’s been a favorite of mine for some time now! Actually, Jazz and Funk have always been a favorite style of music for me.
Bob, you’re pretty fluent in Spanish. How’d that come to be??

[maitai11]

Chris,

As usual, you’re off the chain. Great tutorial!

In my youth throughout my teens, I was into music, and played the drums. I owned a Ludwig Speed King bass drum pedal, which featured a cam and spring return mechanism. My uncle helped me service it, taking out the springs and alignment pins, as well as the plugs on the bottom – but he stopped short on the bearings, probably sensing my overt anxiety over getting that deep into it. There was a minor improvement…

…Until one day I got a wild hair, so to speak, and took the plunge. I removed the caps from both sides, which revealed the most gummed up grease I’ve ever seen! The bearings and cam were both at its mercy

I pulled everything out, cleaned it up, and when I did those roller bearings, you could’ve heard the angels sing! It was just such a beautiful thing to me, to see these beautiful machined pieces come back to life – just with cleaning! There was no way to get to them otherwise…in hindsight, I should’ve just let my Uncle Bob do what he did best – be the great machinist he is! But, I had no idea of the caliber of work he did with that kind of stuff. Still, he gave me the springboard to jump off and tackle it myself – without a repair manual. Doing that made the pedal like it was brand new.

So, in the spirit of renewal, raise a glass with me! Great job, Chris!

Best,

Tim

[Author]

Posts