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View Full Version : Gage Blocks - Care & Feeding



lynnl
01-03-2003, 11:52 AM
I bought an auctioned set of gage blocks (with 3 or 4 large blocks missing) in a nice Starrett Webber Mahogany case (81pc). When I got 'em home I discovered most were not starrett, but Pratt&Whitney, Ellstrom, and Dearborn Gage. Being kinda ignorant in such matters, I have a coupla questions:
1) What's the best way to maintain them? Should they be wiped w/oily cloth, or just a soft dry cloth?
2) One of the slots in the case is for a special "Stone". What kind of stone, and what's it to be used for?
3) Another discovery after getting them home was that 2 of the slots actually contained duplicates, so the set is even less complete than I first thought. Yep! shoulda just bought a cheap import set, which would serve me just as well. Question: Are they available as individual blocks? (...at a reasonable price?) My local supplier wasn't much help.
Thanks for any inputs.

Lynn

Big Dipper
01-03-2003, 12:27 PM
Lynn,
1.)"At work" almost every machine has a set of cheap jo-blocks. They don't get much special treatment other than carefull handling. They get wiped off with just about anything...never saw a rusty one, and a few of the old sets are from WWII. Wiping them with a finger before "wringing" seems to work as good as anything.

2.) Our metrology dept. has "the stone". Supposed to take minor scratches, etc. of the blocks and give tham their "stick" back.

3.) Replacement blocks are available, but only from Starrett, mitutoyo, etc...not from "the imports". A replacement block from one them will likely cost as much as a whole set of china blocks! I have had excellent luck with Starrett for supplying small parts, etc. You can go to their site and e-mail them for a quote.

Uncle Dunc
01-03-2003, 12:35 PM
Dry is better. Oil holds grit, which means abrasion, which is not good. If you're worried about rust, keep them in a warm place, or keep some dessicant in the case.

The stone is for removing burrs. With a light touch you can stone off a burr without materially affecting the thickness of a block. You can tell when the burr is gone, because the block will wring with another (burr free) block.

According to my 5 year old catalog, MSC www.mscdirect.com (http://www.mscdirect.com) sells individual gage blocks. I'm sure other suppliers do as well, but MSC is the catalog I have on hand. They will send you a catalog for the asking, or you can check on the web site for current price and availability.

SGW
01-03-2003, 01:43 PM
See http://patapsco.nist.gov/mel/div821/Publications/Publications.asp for a downloadable paper about gage blocks.

Big Dipper
01-03-2003, 03:10 PM
Thanks for the link Uncle Dunc. I could use a couple replacements, but hadn't thought of a mail order place...DUH!

kgarver
01-03-2003, 03:31 PM
Do NOT leave them wrung together over an extended period of time (like a three day weekend). They are so finely finished that the electrons from one block will migrate to the other block and the holes will migrate back. This is all on the atomic level. BUT you'll know if that has happened to them as they will have a slight brown discoloration one the faces joined together. It will not be even it'll only be where the blocks had the best contact patch. While this doesn't really hurt them it does not help them any either!!
The "stone" is only a very fine, hard Arkansas stone used to stone off the nicks on the edges of the blocks dropped, struck or mishandled somehow. BTW the new ceramic blocks do not suffer from this problem but their cost is truly hair raising!
I keep mine lightly oiled and wipe them off whenever I need them. (I don't use mine that often). They're an Ebay win;new "B" set w/all 81 blocks.
Try Ebay for the missing blocks. They are much cheaper there. I got a 1" Mituyoyo block for $9.00 including shipping. Mitutoyo wanted $26.00 W/O shipping! I got the extra block as cheap insurance as you'll find you use the 1" block most of all.
Keep in mind that all blocks come in different levels of precision. The "B" level is + or - .000050" and the top grade is in the single digit millionths. The tolerances get bigger as the blocks get bigger. Each block manufactured has its own individual number used to trace it when its
calibrated from the manufacturer and when you send it out for calibration. Since you have a set of mixed blocks its entirely possible that some of the blocks have different levels of precision for some of them.
While its not absolutely necessary its a good idea to have them demagnatized. (Keeps the ferrous bearing shavings, swarf, crud,
whatever from clinging to them and grinding away their finely polished mating surfaces!
IMHO the precision from a good clean "B" set is WAAAAAY past what any homeshop machinist really needs anyway!

Get a good surface plate, clean it, clean them, stone off any nicks, wring them together and enjoy the next level (or two) up of precision in your shop!

Regards,Ken

spope14
01-03-2003, 03:34 PM
MSC sells replacement Mituyoyo blocks for a fair price, and I believe even has import type replacements as well.

I have three sets in my shop, Two webber (Starrett), and one Kuroda. Two of the sets have duplicate blocks, I believe in the .100 area size for "wear blocks".

One way to care for the blocks. I use paper to clean them off. Good old copy paper. Put the paper on a surface plate that is completely cleaned off, making sure he paper is also clean, and lightly rub the block on the paper. Cleans it, and gives it the "stick". My apprentice master never used "the stone", this was his method of getting the stick going. Then he would run the block very quickly by his nose to get a bit of oil on it (by the nose, not in it...) to assure the stick. I tried this, but find it better to "fog it" by giving a very light "huff" on it, the moisture from your mouth gives a bit of temporary stick (especially after onions?).

For my master set, I also have a very small Chamois cloth with the blocks. My Kurodas have a felt "cleaner" on the inside of the box lid. I prefer the small chamois as it gives a bit of a stick while cleaning, and provides the "stick". The chamois also gets the grit off the block very completely. I clean the block prior though, don't want to put grit in my neato chamois.

My newest webber set came all covered in cosmoline. I store my blocks with a light coat of way oil on them. They my or may not rust, I do not know. I found a very old one in a small corner of my surface plate cabinet (bought it used), and it was rusty and pitted. I am not one to want to see that again, so I coat my blocks now and then.

I have a 4th set- has a 20 and 40 inch gauge block in it.....got these at a machine shop auction, have yet to find a use for either but just to say I have them..... Also have a 60 inch to 61 inch ID Mic.......

docsteve66
01-03-2003, 04:15 PM
Spope mentions "nose oil". Way back, when I smoked good briar pipes, nose oil was THE best oil for keeping them shiney. Rub a warm pipe on a cold nose in a duck blind and you knowwhat GOOD feels like.

Steve
PS: I consider the aboveto be "on topic" thanks to Spope. http://bbs.homeshopmachinist.net//smile.gif Has any one other uses for nose oil other than smoking pipes and gauge blocks?

Paul Gauthier
01-03-2003, 05:54 PM
Back when I was younger one of the smarter things I did was fishing, I had a few sectional rods and when I assembled them I would rub the female part on my nose to oil them. Worked great.

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Paul G.

Paul Gauthier
01-03-2003, 05:57 PM
Naturally I screwed up the prior post, I meant to say the male part. I got an exscuse though I just got up.

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Paul G.

lynnl
01-03-2003, 06:10 PM
Paul, I won't EVEN BEGIN to say what my first reaction was, before reading your posting more carefully. http://bbs.homeshopmachinist.net//biggrin.gif

Herb Helbig
01-04-2003, 01:10 AM
docsteve -

When I was a lad in college ('50's) my brother in law, an artist, told me to use nose oil to take care of my drafting instruments.

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yf
01-04-2003, 08:02 PM
I read somwhere that nose oil will help preserve elephant ivory and prevent it cracking. I think it was in some knife makers or collectors book. About preserving handle scales on knives.

cblair
01-04-2003, 08:17 PM
Try a lanolin product, this is the oil from sheeps wool and it is sold by several manufacturers in paste and spray form. It is good for wood or metal and it will not desicate or evaporate off. You only need a small amount on a soft rag and it will spread out and last for weeks. The only two brand names that I know of are Lano-lube, paste form, and Fluid Film, spray form.

Charles Blair

Thrud
01-05-2003, 03:07 AM
Lynn

The rub block you are asking about is ridiculously expensive. Mitutoyo's is $300 for the small one and $700 for the large one, but their block care kit is only $565 and includes a block, an optical parallel for checking the blocks, tissues, cleaner, preservative, wood box, tweezers, cotton gloves and a lens brush. Starrett is just as bad. These rub blocks are either Granite or Hard Black Arkansas (not kidding) flattened like a granite plate. I would not try a plain stone - likely to do more damage than good.

I have set of Mitutoyo Cera blocks that I bought new off eBay for less than $300 including freight. They were still sealed in the factory bag and box. Although they are grade 3 (B) their finish and accuaracy are within grade 1 except for the 4" block which is within gade 2 standards for length. These blocks wring better than steel or carbide - Mitutoyo recommends a "light grease" with their blocks, which is weird because that is what the original "Jo Blocks" did as well. I asked them, and the rep is as puzzled as I am. These blocks only require wiping with a lint free cloth or lenspaper and can be left in a stack, unlike their steel counterparts.

Peter S
01-05-2003, 06:40 AM
Years ago in Metrology class, we were taught to clean slip gauges with white spirit before use and wring them together dry. In real life however, I think a wipe with a finger is more common.

Herb Helbig
01-05-2003, 11:52 PM
Thanks to SGW for the NIST reference!

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lynnl
01-06-2003, 12:05 PM
I'm now thinking I'll just forego replacing my missing blox. For my homeshop purposes I don't need ultra-accuracy, in fact I only got that set 'cuz it was cheap. My 1-2-3 blocks sub fine for my missing 1.000 and 2.000.

Thrud
01-07-2003, 01:59 AM
Lynn
Email me with what you need.