Hand held loupe/comparator that can check internal features?

BSCustoms · Aug 13, 2018

Is there such a devise similar to that handheld loupes with reticles that can go into a Ø1.3 bore with something like a periscope arrangement?

We have a part that has internal features being a land of .006" width. Currently we make one, split it and check. It would be super handy to check on the machine.

For final inspection these get cut into 4 pieces so checking is not an issue, but in process is different.

Thank you.

bryan_machine · Aug 13, 2018

I once bought a "periscope" device somewhere off the web, that if everything was just right would seeing into a small bore. So "periscope" like things exist - but it had/has no reticle - you couldn't measure things, just look at them. And it was very hard to use.

I take it the land is behind something so you can't check it with a hard gauge?

There are digital micrscopes now that can do some level of measuring by examing pixels - it might you could put some kind of right angle head on one of those (mounted to a plug gauge like thing specific to the part) that you could insert, and get a workable in-process level view and measurement.

Milland · Aug 13, 2018

There are products called "borescopes" that do what you want, although your size is rather small. Rigid Borescopes - Lenox Instrument Company

For your needs, I'd make a pair of "go, no-go" gages by milling brass or steel bars to have a tab of the appropriate width that would fit (or not) into the grooves (or over the ridge, not clear from description). Simple, and should work for on-machine testing.

BSCustoms · Aug 14, 2018

The land is actually the crest of a helix. Sort of a thread but not. The land width is .004-.008" so I'm not sure a hard gage would service me well. I have tried the "dental putty" but was looking for something a little more reliable and fast. I will check out those bore scopes.

Thanks!

PeteM · Aug 14, 2018

BSCustoms said:
The land is actually the crest of a helix. Sort of a thread but not. . .

If it were a thread, the in process check might be a thread go/no go gage. Any sense making one for your thread-like helix??

As Milland suggested, a cheap borescope should be good enough to quickly tell if the helix is buggered - broken tool, full depth, etc. A bit more challenging to precisely measure the land. I've seen fiber optic borescopes that light and view from the side -- sort of a 1/2" or so diameter periscope. Both for medical use and one apparently for DOD inspection of gun bores. So, it's possible to get something that will look the land straight on -- and calibrate the image from there. Might also be able to use a right angle mirror attachment, plus a snug-to-bore fitting fixture, to use one of today's camera-based borescopes.

Milland · Aug 14, 2018

BSCustoms said:
The land is actually the crest of a helix. Sort of a thread but not. The land width is .004-.008" so I'm not sure a hard gage would service me well. I have tried the "dental putty" but was looking for something a little more reliable and fast. I will check out those bore scopes.

Thanks!

Heh, I originally read the bore as a metric 1.3mm, which is why I commented that it might be small for a cheap borescope. But at the actual size you'll have no issue finding ones that fit. Better ones may have graduated reticles and magnification available, making it easier to qualify the feature.

Could even get some with picture taking capability, would be great for documentation.

bryan_machine · Aug 14, 2018

So it's a 0.006" land in a 1.3mm hole? (Crest like feature on a thread like feature in a small hole, yes?)

How deep in the hole (or does the helix run for some large part of the length of the bore?)

(I don't see how to *measure* it with a bore scope, but you could for sure *examine* it.)

AlfaGTA · Aug 14, 2018

If this is being run on a turning center..think a simple bore scope having a right angle mirror would work..
As to measurement, all you need is a reference line on the display screen....calibrate the scope and set as a tool for "Z" ,(make holder for turret) then move to each side of the feature relative to the reference line..
"Z" move on the control defines the land width and position....
Cheers Ross

Dumpster_diving · Aug 14, 2018

I own an aluminum loupe-like cylindrical device roughly the size and diameter of a pencil. Inside is a magnifying lens with a reticle graduated in 0.001" increments. Not sure how well it would work in a bore (since it's got no illumination) but in theory it does exactly what you're asking. Not sure of the maker, but super low-tech and probably cheap.

Like this: Westward Magnifier, Pocket, 4x 6XY17 | Zoro.com

Mike Henry · Aug 18, 2018

There are lots of inexpensive "endoscopes" imported from China that might be worth looking at.

Search

Largest Manufacturing Technology Community on the Web

Search

Hand held loupe/comparator that can check internal features?

BSCustoms

Cast Iron

bryan_machine

Diamond

Milland

Diamond

BSCustoms

Cast Iron

PeteM

Diamond

Milland

Diamond

bryan_machine

Diamond

AlfaGTA

Diamond

Dumpster_diving

Cast Iron

Mike Henry

Titanium

Similar threads