doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Manson Gauge has arrived...a question...

First thing I noticed is that the ball at the end of the gauge is not going to measure at the bottom of a pit. That really limits the usefulness of the gauge. I was thinking of a way to attach a small brass point to the ball. I was thinking I could either use a drill press to open up a spot, or I could rough up the spot and try blackmax 380, or some other adhesive.

I would be interested in the parts and assembly instructions that others have used to construct a gauge at Home Depot. Is that available somewhere?

Thank you for your thoughts.

There are gages out there that have interchangeable tips, like Starrett. You just have to make sure your needle size threads match the ones you choose. The disadvantage of trying to measure a pit/s is that the needle will get into the pit and if you are rotating the barrel watching the needle, it will move the zero point.

Take a bright flashlight and look down the barrel if the pit/s look dark they might be deep, if a greyish cast, I wouldn't worry about them.
If it still bothers you go to a field that has very low grass, fire a shell and watch for the wad, if the was is not all chewed up from catching on deep pits, again don't worry about it. AND don't hone anything, more barrels have been ruined by honing.

there are 60 degree tips out there that come to a point

i have them on the gauges used to check planing forms for bamboo rods

do a search for "dial indicator 60-degree point"

Note that on one of these barrel wall measuring gauges the Dial Indicator is on the Outside of the barrel. Inside of the barrel is a big round ball on the end of the rod, changing out the dial indicator point is not going to help at all.

DAH, what was I thinking when I wrote mine. Thanks for waking me up, the tip changing has nothing to do with the inside. Just goes to show you, writing before thinking.

I'm building a Manson type gauge from scratch and have thought about jjdawgs observations quite a bit. Really, the gauge could be built with any inside or outside point/pin/anvil/ball you wanted, depending on your goal.

See:

http://www.ebay.com/itm/iGaging-Dial-Tes...=item20d4ad8683

Sharp points would sure make for some difficult measurements, but you'd get closer to the bottom of pits/scraps/dings. Either inside or outside.

Flatter surfaces on either point would make for smooth movements and quicker measurements. But, are you bridging a problem area? What are you really measuring?

What exactly is barrel wall thickness? THE thinnest? Or random ball on a gauge that could span a narrow, but deep pit/ding?

I don't have the answer, but I've sure been thinking about it.

To me, an ideal gauge would be adaptable on both sides of the barrel. Maybe I'm over thinking it.

The ball bearing used on most of these gages are either 3/16" or 1/4" in diameter and are seated half of that in the rod. It will measure pitted areas and if you watch the needle it will jump as it hits one and go to minus.
Putting anything other than a ball bearing on the inside rod in my opinion would not always let the needle come back to zero as it would catch.

I want to be able to measure the depth of a rust pit. They tend to be smaller than the width of the ball on the end of the Manson gauge. That thing is going to bridge right over just about any rust pit I've ever seen.

The ball will read into a pit. Watch the needle and it will move. If you are looking for an exact measurement, you are out of luck, have it x rayed.

It always fascinates me to follow these threads. If you want to see the pitting, then you need an endoscope or a simple inspection tool like the ProVision. I have one sitting here and it has been very helpful. Most internal pitting I have seen is minor, though not all.

If you want to measure the wall thickness in a pitted area, then you need an ultrasonic thickness gage with a corrosion probe.



Pete