Help with Miters!

[Craig Walls]

Hello all,
Miter joints are killing me! Too much time and not enough success. What's a good jig, tool, technique? I have a average miter saw that seems to be set up right, I've tried them on the TS, no luck. I also have probles once one end is cut getting the length right. I want to learn-no, DOMINATE this simple-looking joint. Thanks in advance. Craig

[Joe Jensen]

Can you describe the problems in more detail?
1) You mention getting length right. - to solve this with a CMS, I cut slightly oversize, and then take very small amounts off until it's just right. Here is how I do it. I use a very sharp pencil to mark the cut with an accurate miter marking guage. I use a bridge city tools 45 degree tool to mark 45 degree cuts. Then I put the wood on the CMS and lower the blade down with the saw off and adjust the wood position until the saw blade is perfectly on the line. Then cut. If the the saw is not cutting perfect 45s, then you need to do some fine adjustment.
2) Are the joints not closing properly? Like when you make a frame? This comes down to getting the angles adusted perfectly on the saw.

Also, I have found the blade makes a pretty significant difference on a CMS.

[David Weaver]

I agree with the above. Also, if you have every joint tuned up and have gotten a good blade that leaves a clean flat cut, but they still don't quite fit, dry fit everything and see what needs to come off. You can get the desired result then by sticking a credit card or a business card between the frame of the saw and the workpiece to change the angle ever so slightly. Use a trick then to cut a tiny bit off - turn off the saw and put the blade all the way down, hold the work piece against it and then let the saw up but don't let the workpiece move - you should hear a pinging noise as the teeth scrape by the workpiece. Then, turn the saw on and make your cut. The dept won't be any greater than the difference between than the differnce between the width of the teeth and the width of the rest of the blade.

If everything is properly adjusted, you can get down to it pretty fast, and you won't have to shim things with cards, but if you do have to do that, don't throw everything away until you know you can't fix it.

My buddy and I use a marking knife to just mark the very end of the piece a tiny bit long (like just over the width of the knife line), and then we cut slivers off using the trick above - until everything fits nice.

[Andrew Williams]

you could also "shoot" your miters with a 45 degree shooting board.

[James Phillips]

Hello all,
Miter joints are killing me! Too much time and not enough success. What's a good jig, tool, technique? I have a average miter saw that seems to be set up right, I've tried them on the TS, no luck. I also have probles once one end is cut getting the length right. I want to learn-no, DOMINATE this simple-looking joint. Thanks in advance. Craig

Get a good aftermarket mitre gauge for your table saw. I bought the Incra 3000 and love it. CMS are for construction framing not wood working IMHO

[pat warner]

Rough saw, forget about tuning the bugger.
Then edge-sand in pairs for any angle. (http://patwarner.com/images/miter.jpg)

Routs & sands. (http://www.patwarner.com)

[Stephen C Streetman]

Craig
Had the same problem till I built one of these.
http://www.newwoodworker.com/mitrsldpln.html
You can make it as fancy or plain as you choose. Critical to make the fences at a perfect 90. Spend the time to get that right. Another critical ingredient in mitres is that the opposite side boards are exactly the same length. Any variation there is a deal breaker.
hth
Steve

[Luciano Burtini]

Rough saw, forget about tuning the bugger.
Then edge-sand in pairs for any angle. (http://patwarner.com/images/miter.jpg)

Routs & sands. (http://www.patwarner.com)

Assuming you have the angle correct, then length is your problem. The simple answer is to match pairs (opposite sides). Do as Pat suggests, or if your profile allows, stack the pieces and cut the pairs together. Your finger will allow you line up the two ends and the saw will ensure that the length is identical.

These joints are somewhat deceptive in that they appear so simple. A single mitre is easy, four a bit more challenging when they must meet. The problem only gets worse when you have more sides try an eight sided table!

Good Luck

[Shane Newlin]

always measure from flat to inside/outside cut, or inside to outside cut. mark outside corners whenever you can(wrapping a column).

[Bert Johansen]

The mitered corner is deceptively difficult. Most of the replies have covered the ground, but I'll reinforce a couple of points already made. First, you don't need a high-priced miter saw. I have an inexpensive Black & Decker that I paid less than $100 for, and it works great. Second, you DO need a high-priced blade. Purchase the Forrest Chopmaster--it's worth the extra dough. Third, spend some time adjusting your miter saw until the 45-degree detents are dead on. Once you get it right, you can cut miters all day with perfect fit.

As others have said, sneak up on the final cut to get the length just right. Make tiny slivers until it is perfect. You will need some good clamps to keep the corners tight while you glue them up. And you might consider splines for extra strength. Good luck!