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Forum topic by Zignot5 posted 03-22-2012 06:30 PM 2385 views 1 time favorited 14 replies Add to Favorites Watch
View Zignot5's profile


9 posts in 1722 days

03-22-2012 06:30 PM

Topic tags/keywords: question

I’m a relatively new woodworker & I’ve been doing a lot of reading here on the forum.
I’m looking for advice on improving my work, especially when it come to making more precise cuts & angles.

I’m currently working on a box with mitered corners. It is about to go in the scrap pile because the edges aren’t fitting together well. I’ve tried using a table saw & a miter chop saw but the cuts keep coming out slightly off. It seems that none of the machines are that precise. When that is coupled with my lack of experience the results aren’t great.

What are the best ways to make precise, repeatable cuts? What are the most important jigs to spend time making?

14 replies so far

View NBeener's profile


4808 posts in 2594 days

#1 posted 03-22-2012 06:48 PM

Can you get yourself a plastic drafting triangle ??

Even a cheapie will make it MUCH easier to set your saw blade to an accurate 45 degrees. That’s about the cheapest way I know to get a really accurate miter.

That almost HAS to be your issue, right now.

Best of luck !

-- -- Neil

View SASmith               's profile


1850 posts in 2407 days

#2 posted 03-22-2012 06:49 PM

Do you have a wixie angle gauge?
It would help get your tablesaw (or miter) blade dialed in to exactly 45 degrees.

-- Scott Smith, Southern Illinois

View Bill White's profile

Bill White

4405 posts in 3380 days

#3 posted 03-22-2012 07:09 PM

You can “technique” yourself to death with aftermarket stuff. Get the square that Neil suggested, set up the saw(s) accurately, and start doin’ some great work. Contrary to popular belief, square IS good.
I have never found that “out-of-the-box” tools are really set up correctly. Touch up the tooling. Go to work.



View MattinCincy's profile


128 posts in 2573 days

#4 posted 03-22-2012 07:10 PM

Make yourself a sled for your tablesaw. I have one dedicated to 45 degree miter cuts specifically for boxmaking, and another for standard cuts. There are many designs here on LJ’s.

-- Wag more, bark less.

View Bill White's profile

Bill White

4405 posts in 3380 days

#5 posted 03-22-2012 07:16 PM

Still need an accurately set up saw when usin’ a sled.


View newwoodbutcher's profile


539 posts in 2270 days

#6 posted 03-22-2012 07:39 PM

I recommend buying the Dubby cross cut sled. Works like a charm, lasts forever and all the miters for the rest of your life will be perfect. I used on my contractors saw for 15 years. When I upgraded to a real saw, I bought a new Dubby, much improved over the original and I’m still loving it. Sure you can build something but honestly the Dubby can’t be beat.

-- Ken

View brtech's profile


882 posts in 2342 days

#7 posted 03-22-2012 09:55 PM

The first thing you need to do is to be able to cut a 90 degree angle and know it’s really square. There is a technique called a “5 cut” that allows you to confirm it, but you use a dial indicator on a bar in your miter slot to align your table saw. No need to be fancy. Get a Harbor Freight $10 Dial Indicator, cut a hunk of wood that you mount the DTI (Dial Test Indicator) on, and clamp it to your miter gauge so the tip is in contact with the blade near the edge of the blade. Mark the spot on the blade with a sharpie, rotate the blade around so the spot is on the other side, and move the DTI in the miter slot to touch the same spot. You are measuring the distance between the miter and the blade in two places. You want the difference to be zero. The absolute measurement doesn’t matter. The DTI doesn’t have to be square to the blade. All that matters is that the miter gauge doesn’t wiggle in the slot, and the DTI/bar doesn’t wiggle on the miter gauge.

Then turn the bar with the DTI around and measure the distance between the fence and the slot. Measure in a couple of places up and down the slot. There should be zero difference (actually, some jocks like the back edge to be a thou or two wider than the front edge).

For extra credit, while you are at HF, pick up the mag base for the DTI. Take off your blade, mount the mag base so the DTI can reach down onto the arbor. Find a smooth spot and watch the DTI as you rotate the arbor by pulling on the belt. You should see zero movement as you rotate. That’s “runout” and you are looking for less than .001.

Take a 24” or so square of ply (rectangle is okay), or MDF, or sheet good you have. trim one edge, making sure you keep it flat against your fence. Mark that edge. Rotate 90 degrees clockwise. Trim again. Rotate 90, trim again. Repeat 2 more times. At that point, you have trimmed all four sides against your fence. Rotate again and you are back to where you started, and your square is a bit smaller than it was. Now cut off an inch or so of the square.

Now, you want to measure the width of the cut off piece at the top and the bottom. The best tool for this is a caliper. The $20 HF is okay. Measure carefully.

There should be zero difference. If there is any, your fence is not parallel to your miter slot and/or your blade is not parallel to your miter slot. The error is 1/4 of what you are reading. Go back to step one. William Ng has a great video that shows how to do this.

Then you need to confirm your miter gauge is exactly 90 degrees to your blade. While you can use the triangle to see it fairly well, do the 5 cut test with the miter gauge instead of the fence and confirm.

When you really can get a square cut, exactly 90 degrees, then you want to set up to cut your 45s.

The triangle is an excellent, cheap tool. A digital angle gauge is an excellent, not so cheap tool, but they go on sale for $20 every once in a while.

You should have a good combination square, and the head on it is an accurate 45. You can set your blade with that too. Be careful that you are measuring on the flat part of the blade, and the teeth are not throwing off your measurement.

We are assuming you are cutting your 45 with the blade at an angle, rather than cutting with a miter gauge set to 45. If you are doing the latter, the same tools work to confirm you are at 45 degrees exactly. A sled with a miter bar is a better tool for this than a miter gauge.

You have to hold the work piece really stable as you pass it through the blade. If you are using the blade canted over, a cross cut sled is a much better tool than the miter gauge to hold the work. The sled needs its fence exactly at 90 degrees, and you use the same 5 cut method to set it.

At least for me, being anal about the basics is the key to good miters. The faces have to be square, the miters have to be exactly 45. Miters are one of those things where “close” isn’t good enough.

Then all you need to do is get the lengths right :).

View ajosephg's profile


1878 posts in 2981 days

#8 posted 03-22-2012 11:56 PM

Another “secret” is to cut all pieces of a given dimension at one time with the same setup.

-- Joe

View brtech's profile


882 posts in 2342 days

#9 posted 03-23-2012 01:40 PM

View Zignot5's profile


9 posts in 1722 days

#10 posted 03-24-2012 01:39 PM

Thanks for all the great replies! I really appreciate it. I’m putting all projects on hold for a few days and tuning equipment, building jigs (or buying one), & fixing broken parts. This is a great forum & these answers are exactly what I needed

View MrRon's profile


3891 posts in 2663 days

#11 posted 03-25-2012 06:13 PM

I find the most reliable method to get a square or 45 miter is to make a cut, using scrap; check the angle; readjust; and keep repeating the “tweaking” process until you get your desired cut. This has to be done every time you change the angle on the miter gauge, so make sure you make all your cuts at the same time before resetting the gauge. Machines and their accessories have many limitations. Parts have to rotate, slide, tilt and that means there will always be a certain amount of “slop”. A miter gauge bar that is a perfect fit in the slot, won’t slide easily if at all. A spec of sawdust would be enough to prevent movement. There will always be a few thousands of clearance to allow it to work. All we can do is to compensate for that clearance. The way I do it is to apply side pressure to the miter gauge keeping the side of the bar pressed hard against the side of the slot closest to the blade.

View firewhatfire's profile


21 posts in 1672 days

#12 posted 03-27-2012 07:44 AM

this is some great info. being another newbie trying to learn what does most sleds for table saws need to be made from?


-- May my words and works always be beneficial to God.~~ Me

View brtech's profile


882 posts in 2342 days

#13 posted 03-27-2012 08:17 AM

Look around the site. Lots, and lots, and lots of examples.

The base is either plywood or MDF. Expensive ones use baltic birch ply. Tradeoff of cost, weight and strength.

Front and back fences are either hardwood or laminated plywood (usually BB).

Runners are hardwood or UHMW plastic.

View helluvawreck's profile


22669 posts in 2286 days

#14 posted 03-27-2012 12:48 PM

This is all good advice and I appreciate this thread. I would also say that it is important to have a zero clearance insert whose top face is adjusted so that it’s face exactly matches the plane of the top surface of your table saw.


-- If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music which he hears, however measured or far away. Henry David Thoreau

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