Hi Folks! I've been looking for a source for the flat crystals in digital verniers, (there are many many different ones) got some from Fowler and one from MCS (over many months) it was for an STM 12 inch caliper ended up massaging one of those to make it fit. I can't believe there isn't a bangood or aliexpress store with a thousand of those. Has anybody looked or had any success?
At one point, I looked for a replacement crystal for a dial indicator. There were quite a few crystals available for wristwatches in several standard sizes. I could not find one big enough for the DI but I didn't look all that hard.
On Youtube, a number of people recommend using Mark Ratkowski for repairs/refurbs on metrology equipment:
M.R. TOOL REPAIR
269 LANCATSER DR
CRYSTAL LAKE IL 60014
I managed to repair this one but I have one more that I'd like to repair, it just seems odd, they're held in with two sided tape and really easy to replace.
So Kelly, when you find a reasonable source post it on the list. I would like to change out a curved glass approximately 55mm diameter on an older made in Japan dial indicator which is too accurate to discard. Have a good one!
Hi Bill, you might consider using clear acrylic sheet turned to size. Look at the image below: one of the 10ths indicators has a real crystal glass, the other one is plastic.
And close-ups:
Yes, the one on the left (or the top close-up) has the fake glass.
The ”smudge” below the “No. 77” is from a former owner’s finger print - they kept using the indicator with the glass gone before i acquired them. Got most of it off, but was not taking the chance to ruin the printing on the bezel by scrubbing harder...
There is a company in NJ that refurbishes these (and sells new ones), but it would have cost way more that I was willing to pay.
So...
I made a disc of aluminum (pressure disc) slightly larger than the OD of the glass. Relieved most of the center until only a thin strip at the outer edge was left (only about 20 thou deep). The back side had a center in it. I then turned and faced a piece of aluminum, also slightly larger in diameter than that of the glass. I then rough cut some acrylic with scissors oversized. (There are lots of different thicknesses available for purchase from hobby stores or even Home Depot, Lowes, Rona, etc.). This was then sandwiched between the turned and faced ”driver” and the “pressure disc”. The tailstock was used in the center of the pressure disc to apply sufficient pressure to keep the sandwich together for turning. Using sharp HSS tools, I turned the whole thing (Alu driver, acrylic sheet and Alu pressure disc) to the required OD to fit the indicator. After peeling the protective cover off the plastic and some light deburring to break the sharp edges, I had a perfectly good replacement for a US$200 piece of glass.
There's a number of places that sell replacement round crystals but the one place I found in the US that had flat replacements for digital verniers refused to sell me one. I'll keep looking I keep thinking there has to be a source, I made an inquiry from a Chinese manufacturer, we'll see if I get a reply.
Not sure if its what I played with in the past but its kin dof funky to cut with a scroll saw. The kerf kind of self fuses & heals behind the blade. I thought WTF? - like a magic trick.
Hi Peter! actually they are glass, the LCD screen is behind it. I've sourced 1mm glass sheets in small sizes but they are difficult to cut with no chipping. most have a black border, som have text indicating button function. The lexan would do the job but I was hoping for a more elegant solutiuon : )
Coward, now that's down right nasty. I'm a Canadian veteran with 26 years service in uniform, serving overseas during the cold war, have the medals to prove it. Besides the Lord and I are on excellent chatting terms never once have I heard him say I was a coward. Injured my right knee falling off the tail section of a Voodoo aircraft due to an incompetent supervisor. For the past 22-1/2 months I've nursed a lame leg largely due to that fall. Yes Kelly three (3) knee replacements all in my right leg with the last being temporary. Presently I'm waiting to have that temporary knee replaced again. I am 82 years young, served our country because it was the right thing to do.
Hi Bill! Thank you for your service....... but I was referring to your inability to bring yourself to part with the funds to repair a tool that has obviously performed well and would continue to do so
if given the opportunity. (the scraping sound you may or may not hear is me dragging out my soap box) Our tools serve us well and deserve to be looked after. when accidents happen whatever the circumstance we must be fearless in the pursuit of repair. There thats my two cents on tooling. : )
Hi Kelly, no harm done and thank you for your comments. Understood what you were speaking to just feeling sorry for myself, dam my leg.
On a brighter note its a beautiful day here and I'm still not going to part with my coin, far too many people reaching into our pockets. Can show you the first nickel I ever earned. LOL
