I was talking to Dan (from ToolsinAction) the other day, when he brought up the Thread Checker. I know all about the Thread Checker!, I told him, as I remembered posting about it as part of a larger screw and bolt identification tool post from a long time ago.
The Thread Checker is almost self-explanatory. It’s composed of individual thread gauges that are looped onto a length of steel wire, with each gauge featuring male and female threaded sections.
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It’s a go-no-go gauge, where you attempt to screw an unidentified bolt into the female threaded section of a gauge, or a nut onto the threaded stud. If the hardware fits, then it’s a match for the size marked on the gauge. If not, try again.
S&W Manufacturing, the USA company that makes these under the Thread Checker brand, offers different gauge sets. There’s a 26-size inch and metric set SWTC-26, shown above, which has inch sizes from 6-32 thru 1/2-20, and metric sizes from M4x0.7 to M12x1.75.
Price: $30+
Buy Now(Combo Set via Amazon)
There is also a 23-size inch-only set (SWTC-S21), and a 21-size metric set (SWTC-M21). You can also buy a set that comes with both.
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Buy Now(Inch Set via Amazon)
Buy Now(Metric Set via Amazon)
Buy Now(Inch-only and Metric-only Sets via Amazon)
Wayne R.
These things are great and are pretty much the first thing I look for at the hardware store.
Though they’re not great to carry into the field (unless you’re using a big truck). I have a screw-measuring plate in my main tool bag that, of course, has no studs, but whattaya gonna do?
Mike M
It’s a neat idea, but $30 to $50 is ridiculous.
Stuart
Why is it ridiculous? How much would it cost to hire a machine shop to make something similar?
Let’s say I ran a small shop. Or supervised a team of techs in an MRO environment. It’ll cost way more to DIY a solution than to buy this. There are other thread checkers that are cheaper, but for some threads, a go-no-go gauge is going to be faster and more confident than using other means. I’d approve the purchase without hesitation.
Jim Felt
Stuart. Agreed. And that’s exactly what we’ve done. In all their options. Time is money and these are a very worthwhile near permany investment. Okay. “Permanent”.
Andy
It’s not just about return on investment. I get the value. I have a hard time buying something that has so much margain built in. These things are pretty damn inexpensive to make and it bugs me when companies try to gouge consumers instead of trying to move more volume.
firefly
There are plastic thread gauge at a much lower price point if that’s what you want.
Inexpensive to make? If that’s true I would love to see you make one and sale them at say $20? I would love to see you try that experiment and let us know how that workout. I see a few other comments mentioned how expensive it is. So you already have a few potential buyer already…
Personally I think they are expensive for me but I see why they cost that much. This is not a high volume item. People only buy it one. That mean the manufacture either have to hold on to a lot of stock that they’ll never sales if they want to mass manufacture them. To create something like this require fairly expensive equipment. Those equipment need to be set up and maintained.
I am not a machinist but I have some rough idea what it would take to make something like this. I am guessing this would take at least an hour to make from one round rod. So that’s $30-$50 right there at a minimum.
Andy
If they mass produce it get their cost down to about 7 bucks they could sell them to HD and/or Lowes for abou $8.50. This would allow them to retail for about 12 bucks. Maybe throw some money out for an endcap and they could move 2 units a day per store. And that’s a lot of stores.
firefly
Andy, that’s great! If what you said is true I think this is a great opportunity for you to fill that market and make some money. Even at $15 I think you’ll definitely have me as a customer. I personally see a lot more hurdles. Each of those hurdle greatly add to the cost. For example to get to cost down to 7 bucks even if it’s possible would require a much larger order. So that mean you better have a lot of capital. Then you better hope that your prediction of 2 units is true. Even if you can move 2 unit a days per store soon enough that number will drop because this is more or less a once in a lifetime tool not a consumable. So what are you going to do with the rest of the stocks? What about support? Return? Warranty? R&D?
Again great chance for you to make some money and prove that I am wrong. In fact I would be happy to be proven wrong. It’s really a win win for both of us.
Bob H
I agree with Mike, this is a Great Idea, but it seems to be overpriced. Thank you Stuart for posting this cool concept… I can see some fellows going to the “hardware store wall” and purchasing “one of each” Nut & Bolt then “mounting them” to a small sheet of recycled plastic, with each neatly labeled using Marker or Printed Dymo Tape .
firefly
If you make one and sale it how much would it cost? It’s actually a lot more work than it look, By the time you are done it would cost you at least 2 hours plus at least $10 in parts.
dave
here are the plans for doing it yourself.
https://www.instructables.com/id/Metric-Thread-Verifier/
Dave
Hilton
For me (living in a metric world) the Imperial/SAE thread checker was more important especially as my old Landy has some BSF stuff floating around.
I bought the 26 item SAE version and it’s been invaluable. For a home owner you need this.
I also bought one of those machine screw gauges that Lee Valley sells.
http://www.leevalley.com/us/hardware/page.aspx?p=51784&cat=3,41306,51784
Noah
That thing has saved my butt so many times. They make a mini version too.
Eric
I have the combo version. It is nice to have around and I use it fairly often. I was hesitant about spending the money but I am very glad I did.
I am tempted to get the SAE and metric stand alone sets because I have found bolts that are not addressed in the combo set (although ruling things out helps too).
Big Adam
Always on the lookout for handy stocking fillers that I can hand to my wife to give back to me!
The metric set has gone straight onto my 3xCamel inventory with a $25 trigger.
Thankyou!
Jim Felt
Wow. I’ve never seen them discounted. So I hope you succeed.
But they’re too good of idea if you need them to wait too long for the likely mystical discount.
Unless Zoro carries them. I dunno if they do though.
Rob
Fine for loose nuts and bolts but, if trying to identify the thread pitch on a part it is difficult to move the entire corded tool back and forth.
I work PT at a blue bolt store and use a bolt gauge 90% of the time. https://www.amazon.com/Stainlesstown-Bolt-Thread-Gauge-Blue/dp/B00XUUGKTC/
NewtonsApple
Similar to yours, I like this one a lot for screws only. I would actually like if it was twice as thick as it would be a little more accurate when you don’t know if what you have is metric or SAE.
https://www.amazon.com/Screw-Chekr-Thread-Gauge-Checker/dp/B0006NFUJW/
NewtonsApple
Oh and to be clear, the difference is that the holes in this plate is actually threaded.
Rob F
Yeah, we have one of these on the front counter but, the plastic threads stip too easily.
Jim Felt
I’ve seen these in retail hardware stores and find them kinda useful.
Maybe they’d be good as a fixture as opposed to a misplaceable “chain”.
Yeah. I know. “The price”. But maybe?
Horizontal Bolt and Nut Gauge / Thread Checker (Inch & Metric) https://www.amazon.com/dp/B00OM1HUJ2/
Joe framer
Dan is a trip .. interesting channel. I think TIA was my first sub…Eric is more tool savy……I bought this thread checker, it hangs in the shop,just in case… easier to bring it to a fixed thread of unknown size…
Evadman
I have recently needed this while working on my truck and pinball machine, but all the bolts were fixed and couldn’t be removed. Meaning it would have been impossible to screw this on since the cable would be in the way. If they made a set where each bolt/socket was separate in a case I could throw in my toolbox, I would be all over this.
If I can remove the bolt, I just bring it to the hardware store for identification since I know I also need the replacement hardware.
Lynyrd
Ummm, cut the cable?
Frank D
I look at this and could maybe justify one of each, considering they’d be a lifelong purchase, hanging somewhere in the garage; but one extra second later … I don’t think so … try to check / thread identify something with that whole snake attached … leading me to think I’d have to buy this, cut the cord upon arrival and have to find some storage organizer.
Mick
Gotta love the thread checkers. During the clearance sale of a local Lowes that got the axe, I was stocking up on nuts, bolts and whatever else I couldn’t live without when the thread checker caught my attention (same as the link). Two were complete so I grabbed them for $10/ea. Oh yeah, they really come in handy when sorting through several pounds of misc. hardware.
https://www.primetools.com/collections/thread-checkers/products/1-tu58-thread-measuring-gauge-vertical-bolt-and-nut-gauge-thread-checker-inch-metric
The What?
These aren’t as easy to make as people think and a decent thread pitch guage is going to cost almost the same or more if you bought both the male and female pitch guages separately. And I highly doubt any of the guys whining about the price own or know how to operate a cnc machine to machine these or have a clue about how to gear a lathe correctly for threading and boring metric and imperial thread pitches to spec. These weren’t made by hand with some dude using a vise and a tap and die set. If they were, they would cost a lot more than $50. There’s a lot more to it than you think.
Nate B
I have a set of these and while they’ve saved my butt a few times, they’re way more awkward to use than I expected before purchase.
The cable is quite stiff, and if you’re trying to suss out the thread of a fixed hole somewhere, twirling the entire assembly around is no fun at all.
It’s nice that the individual pieces don’t wander off, but I feel like some fishing swivels or something would greatly improve its usability.
GRADY
Nice tool . I have even considered purchasing one my self. But, I’m to old to change now. So I’ll stick with my tried and true calipers and a screw pitch gauge.
Yes they seem expensive but as a machinist since 1972 i have made a screw or two. Inch, metric, pipe , corse, fine, extra fine, and a few hand full of different thread profiles. Ive worked in shops that had these type of thread id tools hanging on shelves where the fasteners were kept. Mostly when a machinist needs a bolt or nut, calipers and pitch gage is all that is needed. Or you could invest in thread micrometers or micrometers and a set of thread wires, and a machinery handbook. But tnen again ive seen books the size of a machinery handbook with nothing but threaded fasteners. Like i said, nice tool, if you handle a lot of fasteners, but for a DIYer ? If its worth it to you, go for it.
John
I want the Combo….but not through Amazon. Anyone know of a tool company in the states that would ship USPS to Thailand? The Home Depot and Lowes don’t do O/S delivery. And it looks like Sears don’t stock it and no longer do international deliveries!
Lynyrd
Bought mine on eBay for about 40.00 for both. Handy, simple, reduces headaches…
John
I never thought of ebay! Found this “JMS Tool Supply Indiana: Thread Detective Nut & Bolt Size and Thread Pitch Identifier Gauge SAE / Metric Standard Size Range: 6-32 thru 1/2-20 / M4 thru M12 US$53.47 with 1st class USPS delivery ” Would like some bigger sizes as well as there are some big bolts on tractors and farm machinery!
Dalen F Snow
I guess I’m old fashion . I have always used bolt size gauge and pitch gauge set. The pitch gauge sets came with my tap and die set . The plastic bolt gauge is cheap and easy to find . Quickly checked amazon and found them for around seven dollars. This set being discussed here looks like it woud get tangled up in a tool box. Just my opinion on the discussion .
John Patel
Man I really want one but I know I’d only use it once every two years or less. But I hate extra trips to a hardware store. I’ll wait a while before I buy just because it’s hard for me to justify it. I dont think its expensive for those identifying parts frequently
George Curtis
I dont see this as a bad price if I dealt with a lot of differant nuts and bolts.
mikeakafazzman
Love how all the clueless folks think these are easy and cheap to do. I am a machinist and manage a shop.
Even with our CNC lathes and mills I doubt I could do these for under $100 without getting crazy with fixturing and made thousands of sets which would be a waste of my time honestly.
Material prices change daily,setup time for each size,employee pay cost etc etc. Its not cheap to have something machined,heck we charge $150 an hour shoptime minimum.
Stuart
To be fair, it’s hard to judge pricing.
Richard
Is there one of these for smaller metric screws and (even a separate set) for smaller sae screws? I work on lots of smaller equipment and would love to size all the screws to build spare kits.
Stuart
There’s the Thread Detective (available via Amazon), but I don’t think its made by the same company.
Noah
I have that exact set. It’s been a lifesaver.
Rx9
These things are worth the money.
PB
I’m probably missing something but can’t you just use the following method:
1) Measure with a caliper. (Honestly, this is really important if you are dealing with a very special thread.)
2) Manually count the # of threads over the length. (You can tell is the thread is coarse or fine by looking at it.) This is harder to do with shorter thread lengths.
3) Derive whether it is standard or metric based on the above and where the thing came from. For example, cars are metric, some have both.
However, I wouldn’t say no to these if someone tried to give them to me.
I still think thread gauges are somewhat important because you can view the profile to inspect the thread to make sure it isn’t just the right size but also the correct profile. But even these I barely use when I have good calipers.
Stuart
You can, but measuring threads is not as fast or confident as a go-no-go gauge.
And if the environment is a workshop or facility where there are multiple workers, will each one be trained on what to do? Using the same measuring techniques, two different people might get different results.
Is the hardware 10-32, or M5? That can be hard to check by measuring, or at least harder than checking go-no-go fit with known hardware.
An inexpensive gauge is a better idea for infrequent use, but with more use, something like this Thread Checker can earn its place in the toolbox, pegboard, or cart.
Gauges like this can make certain tasks easier, but there are other ways and less expensive gauges of different kinds that can achieve the same results. The difference will usually be how much time and effort go into it.
Let’s say you have a threaded stud on a pieces of equipment or large machined part, and you need to order fasteners, or machine some kind of mating hardware or knob. A thread gauge plate might not fit or be practical. Measuring it might be hard, or less than 100% confident. This would be an application where these gauges might be the best tool for the job.
This isn’t a must-have. I don’t have one, and I probably won’t buy one, because it wouldn’t see all that use.
Mau
I can understand how this tool can be handy, for example in a store where you have clients seeking for a replacement bolt.
I also think that for 90% of the DIYs a caliper and a thread gage (and even this sometimes is overkill) are enough, expecially looking at the price.