Dial gage questions... - PeachParts Mercedes-Benz Forum

JamesStein · #1 12-15-2004, 11:04 PM

Forgive this rather dumb question...

I'm looking at purchasing a dial gage. Problem is, I've never used one and I have no idea what exactly I should buy.

Looking at the pictures it looks like I would need some way to mount the gage so it remains stationary.

If you were in the market for a dial gage. Specifically to test chain stretch and you didn't want to spend a fortune, where would you look? What would you get?

rwthomas1 · #2 12-15-2004, 11:24 PM

James,
What you are looking for is a dial indicator with at least a 1" capability that reads in 0.001 increments. If you have the money get a Brown&Sharpe or a Mitutoyo. To secure the dial indicator there are magnetic bases with adjustable locking arms to allow you to position the indicator where you want it. www.use-enco.com Look under measuring instruments/drop indicator/dial type. Get a catalogue from Enco. Its easier to see what they have in the "paper" version. RT

Eskimo · #3 12-15-2004, 11:30 PM

Quote:

Originally Posted by JamesStein

Forgive this rather dumb question...

I'm looking at purchasing a dial gage. Problem is, I've never used one and I have no idea what exactly I should buy.

Looking at the pictures it looks like I would need some way to mount the gage so it remains stationary.

If you were in the market for a dial gage. Specifically to test chain stretch and you didn't want to spend a fortune, where would you look? What would you get?

There might be a fellow forum member in your town who would loan you one (hint, hint).

(PM me if you're interested.)

leathermang · #4 12-16-2004, 07:54 AM

I am really glad to hear someone interested in getting a dial indicator...
In the past when I suggested this ( as the FSM shows to do ) all sorts of people told me I was off base....

I have had the Enco dial indicator for years.. but I got it locally... I got the straight arms/magnetic base with it at the time... maybe $30 for the whole shebang...

The locking fully articulated arms are THE CAT'S MEOW for nice... but are more expensive..

But I was in Harbor Freight a year ago...and they had a manager's special on a dial indicator with even bigger face than mine... both are the specs which RT mentioned. I got a beautiful China made dial indicator for $6..... Even if it was not accurate I don't know how they can make it and ship it to here and sell it for that...

So naturally when I got home I got out my feeler guages, my old Enco and this new cheap job to compare.... I could not find any difference in accuracy...

For full disclosure's sake... it is also possible to make that measurement by using feeler guages stacked ... etc.... and some way to mark the starting position of the valve... but that would deny you a good reason to add a most useful tool to your collection.... you WILL find other uses for it once you own it... but if this is the ONLY time you need it.. then borrowing it would be great for the first time...

If one does NOT have the fully articulated locking arm... then if possible it would be nice to make a ' bridge' over the cam area... preferably out of magnetic material such as steel... but could be wood or aluminum and secured in place...to allow the positioning of the dial indicator in line with the valve more conviently.. because the magnetic base does not sit very well on the narrow lip where the valve cover contacts the block...

Pete Burton · #5 12-16-2004, 08:12 AM

Both Enco and MSC sell sets with a gage and a magnetic base holder for about $20, and I wouldn't be surprised if you found a MSC that you could walk into and get it locally today for that. These items have to be the equivalent of a "loss leader" at a supermarket. The one I got works surprisingly well and compares favorably to a fully jeweled Brown & Sharpe gage I keep for close tolerance work. The B&S rarely gets used, it stays safe in the toolbox, and if the cheapo gets smashed, so what? It's great for general work, and at the prices available, the decision is easy. Hell, that's cheaper than a TORQUE WRENCH. Sorry, couldn't resist

leathermang · #6 12-16-2004, 08:21 AM

I should have gotten in a plug for Bass Tools in Houston...very good prices on lots of stuff.... but the worst web site I have ever seen....
Send for their Paper Catalog.... TxBill picked up three and brought me one.. so I don't know how much it might cost or if they charge for shipping... but it is a big beautiful catalog with good prices on lots of stuff...

Douglas.Sherida · #7 12-16-2004, 08:17 AM

James,

For what its worth, I recently did this same job with a borrowed indicator (digital Mitutoyo). In the process I discovered a couple of things that you might want to keep in mind while looking at your options.

1) While you are only measuring a 2 mm detent at the valve spring, the body of the dial needs to be several inches above the valve spring to clear the valve rockers and cam. So, make sure you have a "probe" that is at least ~ 6 inches long.
2) The set up I borrowed had a very strong rare earth magnetic base. The nearest flat surface that you would logically want to attach it to, however, is on top of the intake manifold which is aluminum

. So, if you are planning on a magnetic base, make sure you have enough reach with the support arms.
3) I mentioned to one of the physicists in the lab next door that I was surprised at how inexpensive dial indicators were. He stressed that if I were looking to buy a new one I should go with a digital unit, as it is much less expensive to manufacture a high quality digital instument than a an analog one (with a traditional needle guage).

I would also guess that a 0.5" measuring range should be more than enough (I can't think of when you would need to measure a difference greater than that). More important is the number of significant figures, the more the better.

Pete Burton · #8 12-16-2004, 08:35 AM

Quote:

Originally Posted by Douglas.Sherida

3) I mentioned to one of the physicists in the lab next door that I was surprised at how inexpensive dial indicators were. He stressed that if I were looking to buy a new one I should go with a digital unit, as it is much less expensive to manufacture a high quality digital instument than a an analog one (with a traditional needle guage).

I would also guess that a 0.5" measuring range should be more than enough (I can't think of when you would need to measure a difference greater than that). More important is the number of significant figures, the more the better.

Yeah, I guess he's right about the good one, but this physicist knows that you can get a really cheap analog dial gage for $10 or less with a 1" travel. I used it to check my valves by locking the magnetic base to the iron head. I had to put something between the valve and the indicator to get it to reach, like a socket or something. If you set it up and the dial traverses along the same range within 0.001, that's more than enough to check the valves. Oh, BTW, with an analog gage, you can see "motion" on the needle for checking surface roughness and play between components, basically dynamic effects. You can't do that with a digital gage, even a great one, because the analog needle motion is instantly transferrable into an amplified representation of the motion at the analyzed surface.