Comments on: Accuracy in Woodworking

By: dakfl

dakfl — Sun, 14 Oct 2012 15:19:51 +0000

As a past aerospace machinist I concur with most of the posts here. I have used all kinds of measuring instruments from 6″ rules to light waves and am comfortable with with my quality German made Craftsman dial calipers. The only suggestion I would make is to use a steel block of known exactness to compare the zero setting to 1″ and 2″ and so on. The dial may not read exactly what you open it to even if it is at zero when beginning. Most important to me is that the tool repeat every time you measure something other than zero. Your caliper may read “0″ at zero but may read “1.0030″ when opened. If it repeats this every time then you just remember deviation.
Remember, measure twice and cut once!

By: WCR

WCR — Sun, 13 May 2012 19:02:37 +0000

I must agree with you completely. Being a toolmaker/machinist my dial calipers are always on my bench. A while back I even wrote a blog article on this subject. http://newbritainboy.wordpress.com/2011/02/24/31/ However, you put it much more leoquently than I did.

By: Christopher Hawkins

Christopher Hawkins — Sun, 13 May 2012 13:18:04 +0000

I’m not sure I understand “dial it in” vs. “”calling it in.” Please provide additional information to clarify this.

By: Steve_OH

Steve_OH — Wed, 09 May 2012 13:17:18 +0000

Mitutoyo makes digital calipers whose batteries last a lot longer than in the generic ones. Of course, they cost quite a bit more, around $120.

-Steve

By: Danny H.

Danny H. — Wed, 09 May 2012 02:41:43 +0000

I’ve used one of these calipers(the plastic one made by General) in my woodworking almost from the start, 25 years ago and I use it nearly every time I’m in the shop which is almost everyday. Over the years I’ve acquired quite a collection of them. I think I have at least six of seven different brands of them to date. and I’m with what repeter said on using a non digital one. The digital ones in my experience don’t seem to be as accurate and it seems I’m always replacing the batteries in them. The one I like to use most is the one with measurements in 64ths and hundredths of an inch. Because of my experience with these digital calipers I’m not a fan of any digital tools, except for one. That being my digital fence set up from Accurate Technologies. In combination with my Beismeyer fence I can get consistent accurate repeatable measurements within several thousands of an inch. Probably the best upgrade I’ve ever made to my table saw. Extremely helpful when cutting multiple matching dadoes.

By: clifft

clifft — Tue, 08 May 2012 17:20:19 +0000

Have a Ridgid saw with supplied fence which is reasonable.
Other fences may be more accurate, but my concern is repeatability. I use a piece of wood of the desired width
between the blade and fence to adjust and make all similar
cuts at the same time when possible.

Have a mortise and tenon jig, but don’t use it anymore,
as I only use the Leigh FMT with router for that purpose.

I have an adjustable router jig to do dados, so my table
saw is only used for crosscutting and ripping.

I work almost exclusively with pine which is not 100%
stable, so extreme accuracy a bit elusive.

I would never measure to the end of a rule, if the only
device at hand, start at 1 inch mark. Of the many calipers
I have, one measures to 4 decimals, but pine is soft, and
depending on how tight I squeeze the material, I can get
quite a variation in readings.

The proof is in the fit in the end.

By: riooso

riooso — Tue, 08 May 2012 15:47:12 +0000

Great article! Accuracy when done during the cut is a whole new world.

It is amazing what accuracy one can get from a good fence calibrated with a dial caliper on a table saw. I have a similar fence that came with my Jet cabinet saw and has the benefit of having two lines on the sight glass that are about 1/8 apart to eliminate parallax. What a boon to my productivity. A 1″ rip is good to plus or minus 9 thousands, something that I could not have imagined in my younger days.

Another side benefit in having a really great fence is that when I want to make a 14″ crosscut I can use the fence to measure the cut and easily swing the fence aside during the cut. I only have to measure once and it comes out perfect every time.

By: robinmcc54

robinmcc54 — Tue, 08 May 2012 11:17:05 +0000

Long before I was a woodworker I was a machinist. The term “dial it in” was the opposite of “calling it in” and I came to appreciate not only the precision, but the repeatability of “dialing it in.” Resetting the fence on my Jet cabinet saw to the exact place it was before was impossibility. I could get close–acceptably close given wood movement–but it was always an pain and cause for anxiety.

When I upgraded to a SawStop (yes, I can be careless and I know it!), I added a Incra fence. It is awesome! Combine that with a digital depth gauge and I can repeat a setup quickly, accurately and without the anxiety. Now I can do things in the order that makes sense to me, not that requires all the same operations to be done at once.

By: keithm

keithm — Fri, 04 May 2012 20:24:41 +0000

… and then we have http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/%E2%80%98i-want-my-micrometer-%E2%80%99

By: renaissanceww

renaissanceww — Fri, 04 May 2012 13:12:52 +0000

The first “unapproved” song (my teacher believed music died around 1870) was the theme song to WKRP. Yes lock your doors mothers, I was a real hell raiser.

“Baby, did you ever wonder? Wonder whatever became of me. I’m livin’ on the air in Cincinnati. Cincinnati, WKRP”