Urgent Measuring Equipment Advice

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Good Day to Y'all, I'm in need of some advice on measuring equipment, I'm in the Air Force and we have been tasked with tracking a large amount of bushing wear on the landing gear for our aircraft. There are over 125 bushings from .250" to 4.000" and if the bushing is bad, the housing bore will have to be measured too and recorded. Up until now we have been using "GO - NO GO" Gages and if the bushing or housing was bad and needed to manufacture bushings we could use telescoping gages and micrometers to get the size. Some of the work, the gear or components are worked in our shop. Some have to be worked on the aircraft and space is limited. They also want us to record the measurement to .0001" also. We have a lot of aircraft and only a few days to get all the bushings measured and recorded.

My question, is there anything on the market that can assist us and make this tasking easer and faster? We are also limited on funding and would like to keep it under $5K but will consider everything. I've been looking at the 2 point pistol grip sets, air gages and other types like laser but haven't been able to find a lot of info. We would like something digital and fairly simple to set up, use and a lot quicker than what we currently have. Any and all reasonable suggestions will greatly be appreciated by all of us.

I've called several tooling places down town but lately it seems that they are just sales people and have no one that knows much about what they are selling. What I've been able to find is vast and can be pricey and overwhelming.
We in the military are not privy to the vast amount of new items on the market. Most shops are set up to work as a field maintenance unit and have the tooling required to work what we have. Lately they have been pushing a lot more down to field level but it is up to us to find or make the tooling required. Thank God that I had the privilege to work with a lot of you old school guys on conventional machines. Y'all taught me a lot at a time when we had very little to work with and a lot of what we needed we made. Thank each and everyone of you.

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Although you stated you were tight on room to work in some applications, good dial type two contact point bore gauges (sunnen style) would be my suggestion. Take measurements at four or six places around the bore. Go-No Go gauges, three point mics (Intermic), and air gauges will not accurately indicate an out of round condition which is what you are most likely dealing with in measuring bushing wear.

Another considerable factor is the size of the bushings to be tracked!

Glenn

Glenn Wegman said:

good dial type two contact point bore gauges would be my suggestion. Glenn

Click to expand...

I agree. Check out Mc Master Carr 20685A665, and then look at the catalog page for a better idea of size range and pricing. They are not cheap, but very accurate, and will give you the ability to check out of round.


http://www.mcmaster.com/#

You might want to check out the machine tool show in LA, WESTEC coming up in a couple weeks. Might be too late for what you need now, but would be good to see what else is out there that can help.

http://www.sme.org/cgi-bin/get-event.pl?--001777-000007-home--SME-

Dial bore gage.

I suspect these days they can be had with digital
indicators.

What you need to know is, those give a relative
reading so ideally you want to either purchase or make
a set of setting master ring gages to get the numbers
at the 0.0001 uncertainty level.

If you have unworn bushings whos sizes you trust, you
could consider using them for setting masters possibly.

Jim

I believe we have a Metrology section here too, so post there and what the QC-oriented guys/gals have to offer.

A Vote for the Sunnen bore measuring system. Has several advantages...First off you do not need master ring gauges with the Sunnen setup. They have large format master micrometers that you use to set the gauge...allows large range of size checking with one master tool. Gauges can be set directly to a tenth and the indicators read to a tenth. Would go with analog dials myself. Digital stuff is great on new work, but to see what you really have on worn stuff it is nice to have a dial.
Also has the advantaage i believe of being US made................and they have (Sunnen) field tech reps that can be of help in choosing what you really need.
Cheers Ross

What AlfaGTA said.

http://www.sunnen.com/ProductDetails.aspx?ProductID=23&NavID=666

Sunnen has the most versatile and most comprehensive ID dial bore gage line, as well as being the most dependable and easily set up and easily read. They are used in just about every decent engine rebuild machine shop. Like he said, all you have to do is call Sunnen and a rep will come to you to determin what you need to do your work.

After using Sunnen, other bore gages feel like toys. I wouldn't want to work on aircraft without them.

Glenn Wegman said:

Although you stated you were tight on room to work in some applications, good dial type two contact point bore gauges (sunnen style) would be my suggestion. Take measurements at four or six places around the bore. Go-No Go gauges, three point mics (Intermic), and air gauges will not accurately indicate an out of round condition which is what you are most likely dealing with in measuring bushing wear.

Another considerable factor is the size of the bushings to be tracked!

Glenn

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Glenn, if he has an odd number of lobes on those I.D.'s, the two point system will have a bear of a time detecting that. Draw a three leaf clover-type pattern and take a look. A two point system might very well call it round.

There are four sizes of Sunnen dial bore gages. They will cover from about .50" to 6.0".

For the holes smaller than .50, I see Sunnen now has an even smaller bore gage which uses split balls rather than an indicator finger. I have never used these gages from Sunnen, but I have used them from other manufacturers. The split balls will be your best choice for the smaller holes, and I can't imagine Sunnen's line not being top notch.

With the master setting gages and small hole probes that will probably eat up all of your $5,000. IMO, there is nothing out there that will give you more flexibility and precision for the money. I have used these gages and they are great.

You could go with someone cheaper, but the disappointment of poor quality will last far longer than the elation of cheap price.

something digital that can be interfaced to a PC with some custom software would make recording and filing all your measurements a snap. would be no problem to have a custom system set up but doubt it would come in under $5K...


dave

Peddler said:

Glenn, if he has an odd number of lobes on those I.D.'s, the two point system will have a bear of a time detecting that. Draw a three leaf clover-type pattern and take a look. A two point system might very well call it round.

Click to expand...

That is an issue, but I think 3 lobed holes happen more often in the manufacturing phase than from wear. Worn hole are more often oval or egg shaped, and the OP needs to measure wear, so I'd think that 2 point measurements are the priority. To be sure, both methods are necessary, but in this case I think 2 point is adequate.

Highpower, I have designed gages that check out of round wear as you describe on aircraft levers that wear in one plain only. This is neither a cheap or quick gage to make but it does the job, in the field.

What I design is gage that has a round pilot dia. about .001 u.s. from the hole to be checked. Next, a small relief groove. Next, imagine a land like a tapered grinding arbor to start with and lets say it's 2.500 long, next 2nd relief groove, last a land of any size to put in a handle. Centers in both ends.

I'm going to make up a range to work with for an o.d. of 1.0000 to 1.0010. I give the gage maker aproximate liniar dimensions to hit with these excact sizes with. (.250from the pilot end with 1.0000 dia. and .250 from the "big" end with the 1.0010. Taper continues beyond these points in both directions.)
This equals .001 taper in 2.000, give or take. We measure the excact lock-up points for the 2 sizes with a ring gage and an optical comparitor. Recording the lock-up point for the 1.000 ring and the space between the 1.000 ring and the 1.0010 ring. For the sake of this we are going to say it is 2.000 for the spacing.
We then wire edm this tapered section to be like a diamond pin, leaving the approrite amount of the tapered dia. to check the feature required. We wire off the diamond point on 1 side to form a large enough flat to mark a scale on, but not all the way to the tappered dia.

Next, the scale lines are marked (wire edm) on the flat we put on. Starting from the lock-up point for the 1.000 ring and spacing every .200 to the 1.0010 lock-up point (.0001 diametrical taper per .200). Here is the catch, the spacing will change as our theoretical 2.000 dim. changes, you have to divide that excact reading by the number of spaces to get the spacing.
This give the gage maker all kinds of room an gives you an accurate gage.
Last we laser mark the scale number next to lines on the scale.
To recalibrate we check the 1.0000 and 1.0010 lines with the rings and check straitness of the tapered o.d. looking for wear between centers on a sign bar.

Probably more gage than you are looking for, but you can stand on a plane wing and check size and roundness of a hole that the gage was designed for with this gage.