Do you have a feeler gauge? If not, you should consider adding one to your tool kit.
A feeler gauge is set of reference tools for measuring the widths of narrow gaps. It’s a sort of go-no-go tool, where you try different gauge blades until one fits.
They come in different styles and sizes. Shown here is the Proto J000AA, which has 25 blades 1/2″ wide x 3″ long. The sizes range from 0.0015″ through 0.040″. Each has both inch and metric-equivalent markings.
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The blades can be removed if needed, but it’s usually not necessary.
I recently had to level the wings of my new table saw, and used feeler gauges along with a straight edge and rule to ensure everything was within tolerance.
In this image here, a 0.040″ (1.02mm) feeler gauge slides freely in the gap between the extension table and a straight edge. It’s out of spec, and the company wanted image confirmation that the gap is larger than 1.0mm before they could send out a replacement.
Feeler gauges can be stacked together if needed.
I consider this to be a toolbox essential, even if it’s not something you use everyday.
Pricing can vary depending on size and blade count.
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The Proto J000AA can be purchased for under $20. It’s made in the USA.
If you want something less expensive, the Gearwrench 161D 32-blade feeler gauge is under $12.
Feeler gauges are also available with bent angles or tapered tips. My stance is that, unless you know exactly what you need, it’s best to start with a straight blade set. Most thinner gauge sizes have some spring to them, where angled tips could be convenient, but not essential.
Inexpensive feeler gauges – the kind that sell for $5 at online marketplaces can be useful as shims in a pinch.
Steve
Don’t have one. I might use it once in awhile if I had one and I’m quite familiar with them. Just never had much of a need in my line of work or personal life…
Mark Slayden
So I hear you. None of the work you do needs to be precise.
Bill
The image of your feeler gauge, which I have a few different versions of, reminds me of my introduction to their use in my childhood. My father, like many dads, first showed me how to use a feeler gauge to check the gap on our lawnmower’s spark plug. Later I learned how to set the gap on ignition distributor points as well valve lash. Those were the days.
fred
I recall wire feeler gauges for spark plugs – or gapping pliers if you were doing many sets at a time. Then there was the distributor wrench, points adjustment Allen wrench, dwell tachometer and timing light to help complete the tuneup.
MM
I have a set of those wire spark plug gauges in my toolbox, right next to a set of extra-long angle-ended feeler gauges for setting valve lash, valve spring compressor, piston ring tools, cylinder hone, timing light, and valve lapping stick. I don’t think I’ve opened that particular drawer in about two years.
Bill
Yes I have the wire type as well, along with a nice dwell meter and timing light. It could all still be useful if I had an old car.
fred
For carpentry or woodworking measuring gaps may not need the precision of a feeler gauge – but shop made or store-bought reveal gauges come in handy.
Bonnie
Still important for setup and maintenance on woodworking machines. Trying to level a jointer bed for example.
fred
True – machine setups/adjustments like levelling, checking for parallel, checking alignment etc. may also benefit from having a long and true (machinist quality) straight edge, I also sometimes (but seldom need) pull out a Starrett machinist’s level (I’m blessed with four that I inherited) or a dial indicator (My Starrett and Brown & Sharpe ones are also WWII vintage) . My Leecraft winding sticks are also useful for sighting along machine surfaces to get a feel for things that may be out of true and which way they might need adjustment. Mercifully, these tasks have not been ones that I need to perform on a regular basis – perhaps because my machine tools (designed for industrial use) get only hobbyist wear-and-tear.
Sadly, the lack of precision for woodworker/carpenters – may come in the form of poor-quality control in tool manufacture or protection during shipping – with no user adjustment being possible or practical. We observed miter saws with tables that were dished (could live with a small amount) – but others that had high spots that were unacceptable. Or how about fences that were well out of square to the table? Then there were fences that were not co-planar side to side.
Bonnie
Miter saws aren’t really intended for fine furniture/carpentry. So I kinda give those a pass on precision. They’re primarily for rough carpentry. There’s a few higher-end options like the Kapex, though I’ve been hearing rough things about the newer batch of those.
But I do hate tools that lack adjustment mechanisms (this is showing up in miter fences) of any kind. No matter how well calibrated it might have been at the factory, it almost assuredly will become out of alignment at some point.
fred
You also read comments about band saws, drill presses, wood lathes, table saws etc. having issues right out of the box. I suppose that there were always some percentages of defective (or sloppy) tools produced during the age of heavy metal machinery – but the modern emphasis on value-engineering may have exacerbated the problem. We also expect that machine tools will be shipped to our shops – easy to move in and make ready for use.
Maybe it’s just expectations that have gotten out of whack. We might be asking too much of bargain tools and/or “free” shipping from Amazon. I recently saw a Rikon radial arm benchtop drill press selling for $450 after a 10% off deal. I saw that it weighed in at 85 pounds. I thought about buying it for a nephew who admired my old Walker Turner that probably weighs 20 times as much (required riggers to move it into my shop). Then I thought better of it after reading some of the negative reviews about it being subject to shipping damage.
We also may not worry as much about longevity of our tools as we did when I was growing up in the 1940’s and ’50’s. The expectation back then was that you bought a tool and expected to pass it down to generations that came after you. Today, we might accept less longevity with the thought that in 10 years (or less) something new and better (or at least better-featured) will come along. That is certainly true for cordless power tools where I am no longer using my old Makita NiCad powered tools – let alone think about passing most of my cordless tools down to my grandchildren. It is also true about some of the machines in my shop. While my 1970’s Unisaw may have better or equal build-quality to modern day equivalents – it does not have the safety features a Sawstop or modern European cabinet saw.
MM
In addition to what fred wrote I also think it’s worth mentioning that with every type of machine you have a range of quality options available. I would never expect high end carpentry performance from a bargain brand slider. Now something like an Omga T50 350? Whole different beast.
What I think is interesting is that some modern tools have only improved: a modern cordless drill from any of the big name companies is far superior to a corded model from the “good ‘ol days”. On the other hand many tools have gone the opposite direction, mainly the large stationary ones. I’ll take an old school DoAll bandsaw which has a manual transmission with a stick shift over a modern saw with a digital variable speed control any day.
fred
We had a Doall plus a big Armstrong-Blum plate saw in our fabrication shop – both will likely outlast most current Toolguyd readers.
You can find other examples as well. My Leica M4 camera has none of the modern features of the small Canon digital camera that I carry while on vacation – but it has a far superior set of lenses and build quality far exceeding many (if not most) of the cameras sold today.
eddie sky
I borrow my neighbors… used about once every 2 years…
Grady
I’ll stick with my Starrett’s, they’re over 40 yr.’s old. I used them daily back then when I was a machinist. Just checked replacement cost, I think I should move them from my tool box to my safe.
Nathan
Not sure if still the case but lisle tools at most autopart stores are USA made and ready to find. I have a 32 assortment if I recall the number right. The brass gage is to use on things that might scratch or are magnetic. And usually there are 2 in a fairly thin size.
Also I think the thinnest ones tend to be SS. Not for strength but for corrosion. A spot of rust on a 0.005 is going to be an issue
Now that modern spark plugs are pre gapped. People used them less but I always verify my plugs before install. Ls3v8. High boost turbo mill or my lawn equipment
Jerry
The brass are commonly used to set the air gap for flywheel magnets on a magneto ignition.
Probably not something many people will be working on anymore.
Jack D
I bought my first about ten years ago for a specific project–I forget which–and haven’t had to use it since. I’m glad to have it nevertheless, it belongs in every shop, even a wood shop.
Nate
Thanks Stuart! This was a great review. I have a feeler gauge set in my tool box from about 20 years ago. I bought it at NAPA when I was working on a 1970s era boat motor. I was setting points, spark plug gaps, etc. These are really useful and it’s nice to know what’s in the market!
Nate
It’s about time I consider renewing that gauge set, I’ll look though these and use your link!
Nathan
1970s was a bit more than 20 years ago. 😀
Nate
The boat motor was from the 70s. I worked on it in 2004. Boats have long lives. 😉
Saulac
Reminded me another tool that I wished I had known earlier and everyone should also has: the orifice cleaning tool. It is in my “core tool box” now.
Chip
Feeler gages, setup blocks,levels,straight edges,squares,digital angle finders,calipers are useful in new equipment setup….or most repairs.
An adjustable wrench can become a rough caliper, playing cards can become feeler gages ,levels can be a square on a vertical surface…but a string can be used for all.
Speaking of gapping spark plugs,I carried a circular champion spark plug gage on my keychain from mid 80’s -about 2004.
DRT42
I have several sets, and had to buy another set with bent tips last year. Required to set valve clearances on engines with mechanical lifters (i.e. bucket type lifters). Most modern engines have hydraulic lifters, so it’s somewhat of a fading art. I suggest storing these with a bit of oil on the blades, as they seem to be the first tool in my box to begin rusting. Rust increases the thickness of the blades, making them inaccurate.
Tony
I frequently use a bent feeler gauge (blade tip is bent 45 degrees) as a tool to spread wood glue into tiny cracks of wood that are splintering off a board. The blade lets you apply glue into the crack without pulling the splinter away from the board and breaking it off. A .010 inch blade is thin enough and stiff enough for this. Painter’s tape holds down the glued sliver of wood until it drys.
This is my first post on your blog and I enjoy reading your news, reviews and opinions.
DRT42
That is a pretty good idea. I will have to remember that one.