In Search Of.....

[clowman]

The perfect mitre. You know, the kind that are machine made. The kind you see on picture frames. I want mitres that are tight, elegant. While I realize nobody can tell me what my problem is. Ok, maybe you can, but what I am looking for are tips, tricks, techniques to accomplishing this elusive task.

Here is what I have tried. I have set both my table saw mitre gague and my mitre saw that I am pretty sure cut on an accurate 45 angle. ( I say pretty sure, cause if it does in fact cut an accurate 45, the mitres should all fall into line when I make the frame ). I am thinking it may be my assembly method. Heck, I don't know. My problem is, that when I go to put the frame together, I nearly always have "gaps" in the joint. Usually on opposite ends of my frame, mostly on the outside edge. How do I fix this? It's definately possible that I have 2 machines that don't cut perfect 45s. I make sure that the 4 sides of the frame are of equal length, thickness, and width.

What do you people do to get nice tight mitres? Got anything to share?

 

[Steve D]

Clay,


The best method I have seen uses the table saw with a dedicated sled. The sled has another piece of plywood or MDF attached on its surface that piece is a triangle with a 90 degree corner so that the blade cuts through the 90 deg. point. One side of the angle is cut on the left side and its mating piece is cut on the right side. Even if the setup isn't perfect you still end up with a 90 deg corner. You need to label the parts so the mating corners are assembled properly and as you mentioned, make sure that you have the same thickness, width and length.

This is a similar concept:



Steve D

 

[Monty]

Another extremely important point is to make sure the opposite sides of your frame are EXACTLY the same length - this should involve using stops to set the length. Even if your angles are perfect, a slight imperfection in the lengths of the sides will kill the tight fit.

 

[Joe Scharle]

Clay, when mine mess up it's usually because I let the blade 'push' the work. If you find that happening, you may want to try the 2 cut method. First close, second nibble. Especially for the "other" end as the previously cut miter tip will want to slide under any stop block. I always cut the back rabbet slightly oversized because sometimes after all that, I still have to 'kiss' the disc sander! And of course, then I've shortened the piece.

Joe

 

[DavidF]

The last two posts have it spot on - equal length and clamp the piece while cutting the mitre

 

[Monty]

Um... what's a mitre?

 

[chris99z71]

Or if you've got an extra $200 kicking around, I've always thought that one of these would be pretty schweet. It doesn't solve the problem of getting things the exact same length, but once it's set up, it should give a nice clean 45°.

 

[clowman]

You jest with me Insom

 

[Monty]

Actually, I was jesting with DavidF! I didn't notice that you used the Queen's English spelling as well...

Anyway, if you're going to cut mitres instead of miters, you need to make sure you measure it all out in millimeters. ;-) :lol:

 

[chris99z71]

This may make all of you want to run me out of the country, but I'd much prefer to work with the metric system...
Fractions suck

 

[clowman]

Ha.. I was a bit unsure of that spelling, so I looked it up before I posted. I noticed that miter ( which I thought it was ), and the defination was a queen's headress or something like that. I said to myself... "Self.. that's not it". I did of course, neglected to look down a bit further and note that there was another defination as well... What can I say, I'm just a country boy...

 

[cskipper]

This sounds incredibly basic, but we fought with this on a project. It turned out that the fence was just a tiny smith off square with the saw.

 

[Joe Scharle]

I'm with Chris on metrics. Even the Brits who invented the 'feet' system gave it up in the '70's!

 

[DavidF]

A miter is as in "A Bishops miter" - the popes hat is a miter.
Of coarse there is a "Bishops mitre" in wood working carried over from the stone masons craft where one leg of the molding is worked in the stile with a fake mitre, also called a masons mitre.

 

[Monty]

I like the way you talk.


;-)

 

[DavidF]

I'm going to have to work on that insom.