Inside a cheap bore gauge

Using and disassembling a cheap metric bore gauge I bought on Amazon. It is truly both good and bad. I show how to use an indirect reading bore gauge and discuss the good and bad about this extremely cheap precision tool.
It looks like it went out of stock quick but here is the link in case it comes back, in the meantime you might also check Aliexpress.
Bore Gage .0005" Gauge 35-50mm (1.4"-2" Range) - amzn.to/3xljOTH
The previous is an affiliate link, the channel receives a small fee when you use it. It costs you nothing extra.

[@pidjones]

I bought similar on ebay. Mine was Ok out of the box. Great for taper and out-of-round. Helped me determine that RD400c just needed hone and rings, and XR100R a bore and piston. Something that I'll use maybe every three or four years, I'm not spending any more on.

[@theeddies]

I would normally send bores out to be done, so all I would usually need to know is a rough measurement to determine whether it is in tolerance or needs a oversize. The snap gauges work fine for that. But this is better built for taking repetitive measurements while cutting. And like you say, it is not something I am going to use much so is priced accordingly. Thanks, Eddie

[@swanvalleymachineshop]

About the only times i use my one is for measuring big end & main bearing sizes in engine rebuilding . An easy way to set them is to lay the micrometer on the foam lid of the box & the foam supports the bore gauge so it can be rocked in 2 directions to set the size . You will get the hang of it !!! Cheers .

[@theeddies]

Thanks Max! I will try that. I knew there had to be some tricks to it. I have seen a few special jig setups for guys that use these all the time but knew there must be some simpler ways to calibrate them.. All the best!

[@psgflier]

If it's good enough it's good enough. The nice thing about the bore gage is it's easier to measure taper and washboard. Imagine a line of 8 year old kids or young women who have never used one of these, or even seen a machine tool, putting these together. Years ago I used to tune up American made firearms from field units into competition arms. You'd be surprised at how rough " quality " guns are and how just a little polishing and adjustment would make in the accuracy and reliability of a brand name firearm. I converted a few cheap offshore arms too, took a little more work, but most would compete with a brand name.

[@theeddies]

That is exactly what I thought after I figured out what was wrong. The people assembling them just did not know how they work or what they did and just screwed things together. I actually thought about redoing part of the head but like you say, it's good enough for the job, if I just Loctite those threads in the handle so they don't come loose, it will be fine for what I need. If I break it or strip them I can always rework it then. Thanks!

[@DCT_Aaron_Engineering]

G’day Eddie. It actually doesn’t look too bad for the money. The ok’d bore wasn’t too far off 1.5”. Cheers buddy 🍻. Aaron

[@theeddies]

Hey Aaron. For $15 it is a steal, lol. The bore should have been 38mm plus a few hundreds. A 10th over (is it correct to say 0.1 that way or 100 microns or? Trying to work on the nomenclature) is a bit much BUT it is an Italian engine and the pistons are not always perfectly round so there may have been a compromise made or that bore was "plum wore out". I will go further into that when I cut the bore, IF I cut the bore. I have already had another identical one done by my guy but I want to try it on this machine and see if I can hold the tolerance. So far I am getting mixed results. Thanks! Eddie

[@melgross]

It didn’t seem to be a problem “fixing” it. I’m always amazed at how they can build something so cheaply and yet have it work the way it’s supposed to. I often take these things apart as well to clean, re-oil, if necessary and check to make sure it’s actually working properly. These cheap things can work just as well as tools costing ten or twenty times as much as long as it’s understood that you need to know how these work before buying so that you can take care of any problems they may come with. I bought a 6” dial caliper back in the early 1980s that looks just as good as, and works just as well as my Brown & Sharpes and Starretts.

[@craigtate5930]

Good info to share... I am really terrible with snap guages unfortunately, somehow I don't think I would be much better with a device like this

[@theeddies]

The key to snap gauges for me was what I call the Abom Roll. Not because he invented it but he was the first person I saw do it. Check out this video where I demonstrate it, if you are interested. kzbin.info/www/bejne/aJyyZWmLfKeUo8k

[@craigtate5930]

@@theeddies thanks, definitely a good demonstration. I kinda wonder if I don't take enough care in my procedure...might serve me well to practice on something of a known size

[@theeddies]

That's a good idea.

[@1crazypj]

For one tenth the price of a cheap bore gauge, I would say that was a major win. If parts were lapped and polished (and made to decent tolerances) you would have a Mitutoyo (at probably a similar cost) 😁

[@stewanish]

Hi Eddy thanks for the video. Possible to show me the link to the cheap bore gauge? Thanks.

[@theeddies]

Hello, there is a link in the description to the one that I reviewed but it has been out of stock for awhile. There are some similar ones on Amazon but none as cheap.

[@healthymixzemason1397]

Just ordered one and it the same problem i have....ohhh my thank you i was wondering if it came with the spring 😅😅 lol thank

[@theeddies]

Lol. Send me a link, the one I used to order is not available anymore.

[@kimber1958]

that is a nice assessment. For me, Not having one is a better option than having that one. If it was in imperial, might change my mind

[@theeddies]

I hear ya. You can just change the indicator to an imperial one and its imperial.

[@kimber1958]

Du

[@kimber1958]

I never was good at thinking around corners, very simple solution.

[@f.hababorbitz]

@@theeddies Is the indicator mount 8mm vs imperial's 3/8" diameter? I have that problem with mag stands made for the imperial market, tough to find one for metric. They can be had, but sellers on ebay don't specify that well.

[@theeddies]

@@f.hababorbitz it's 8mm

[@TheKnacklersWorkshop]

As you said for $15 it was worth getting...

[@theeddies]

Definitely can't beat the price.

[@rbrown264]

where do you get the matt on your work bench

[@theeddies]

amzn.to/3G7JI0H

[@theeddies]

I sent you a link if you did not get it let me know. Thanks!

[@theeddies]

amzn.to/3xt6RHt

[@testyourdesign233]

Must be popular bore gauge. Already sold out or pulled from market!

[@theeddies]

It sure has, it was just there a couple days ago when I made the link. I cannot seem to find a similar alternative near that price. I know when I ordered it a few weeks ago it said limited stock but figured they would just get more. That stinks!

[@f.hababorbitz]

@@theeddies I think your comment about these being factory seconds is why you can't find them.They ran out of the lot of bad parts made into bore gauges. I have a lathe I purchased in 2004, 18x40, 6000lbs, Grizzly imported them, never in the catalog but sold online. I'm convinced the 6 lathes (customer service told me that number) they brought in, were assembled with every incorrect machined part. It works, but you can see problems with machining. The tail stock quill had a machining error in the #4MT socket, that prevented the tool from seating correctly. They had a parts machine (a whole spare in Pennsylvania) that they sent me the quill from. Oh, and I had to machine it down 4 thou to fit the tail stock bore (Eli Whitney is not in their factory). Also had issues with the D1-8 spindle nose cams having detents that were not aligned for them to allow easy insertion of the chuck pins. Many many problems like this. A true preassembled kit lathe. I wanted the large spindle through hole for shaft work. I have to say it's accurate, as it is very solid and rigid. The one thing China seems to be able to do, is get the spindle to run parallel with the ways, at least on machines above the hobby grade. My point is, China does not scrap parts, they put them in special export lots, and you got one of them.

[@f.hababorbitz]

I purchased the set of these bore gauges from Enco when they were still in biz. I thought they would be very useful in the shop, I've used two different sizes. They are handy for checking engine cylinders for any wear that is uneven. But absolute measurement, you can see they are a bit hard to set up for that.

[@theeddies]

@@f.hababorbitz It is very possible that was the case with this. It just has that feel of "not quite right" even by the stereotypical Chinese tool standard. There is actually some good quality coming out of China now but not this one. But it works, and for the money I cannot really complain.

[@williehofer8107]

If the telescoping gages are not accurate the problem is the user

[@johnstrange6799]

I can imagine someone buying a boatload of these for $15 and selling them for $45-$60.

[@theeddies]

Well they are out of stock, so...you want to buy a bore gauge??

[@johnstrange6799]

@@theeddies Nah. I have no need for one.

[@theeddies]

@@johnstrange6799 need to watch Skywave400lt... newest video. He has some original "blues based" sounding music in it with some odd Japanese/Asian phrasing and tone pallette. Nothing jaw dropping, just interesting.

[@theeddies]

@@johnstrange6799 there is a 10" atlas near me for 500

[@johnstrange6799]

@@theeddies On where?