Replies

1. 
   MikeHennessy | Nov 30, 2009 10:42pm | #1

   You should be able to set up your saws to make an accurate 45° cut, but if not, eschew the modern technology -- use any saw to get close, and the venerable miter shooting board and a sharp plane to tweak it that last 1/2°.

   Mike Hennessy
   Pittsburgh, PA
   Everything fits, until you put glue on it.

1. 
   Eireannach | Nov 30, 2009 10:48pm | #2

   Don't you have to be able to make an accurate miter cut to make a shooting board to make accurate miter cuts?

1. 
   MikeHennessy | Nov 30, 2009 10:57pm | #3

   It does have to be accurate, but you can sneak up on it with repeated tweaks. Also, FWIW, I keep accurate 45's around to use to make 45 cuts. I use my radial arm saw to make most miters because I think it's safer than crosscutting on the table saw. But I have a draftsman's 45 and my Starret 45 to set the blades/jigs accurately.

   Another way to skin this cat is to make an accurate table saw sled. You can make the miter fence initially adjustable, allowing you to sneak up on perfection, at which point you permanently fasten the fence.Mike HennessyPittsburgh, PAEverything fits, until you put glue on it.

2. 
   RalphBarker | Dec 02, 2009 07:47pm | #9

   I had the same question when I started looking at shooting board designs. The conclusion I came to was to design the shooting board so the fence could be shimmed/adjusted to achieve a precise angle. So, mine has a backer board behind the working fence and enough adjustment to accommodate the shims. I also use the shooting board to get corresponding pieces *exactly* the same length.But, like on a saw, movement of the piece during the cut is still an issue, so clamping is required.

1. 
   Eef | Dec 02, 2009 10:00pm | #10

   hey ralph,
   what type of hand plane(s) do you favor for use on your shooting board?
   eef

1. 
   RalphBarker | Dec 02, 2009 10:42pm | #13

   I'm a bit plane-challenged compared to many here. I've tried both my #4 Record smoother, and my #7 Record joiner. The heft of the #7 helps with some woods, but is more of an effort to use for the same reason.

2. 
   Eef | Dec 03, 2009 12:35am | #17

   ralph,
   yes,i too am quite plane-challenged. my next ray of sunshine will be an appropriate hock blade and greater determination. i simply MUST have a good shooting board and will likely not rest until that time.
   eef

3. 
   RalphBarker | Dec 03, 2009 02:41am | #18

   You should at least take a nap now and then. Not resting at all can kill ya. ;-)

4. 
   Eef | Dec 03, 2009 04:11am | #19

   ralph,
   yes, i know. so, fellow challenged one, what say we both employ one o' them hock blades, shoot our wooden brains out with it, and compare tips and notes as we come to gain the perfect miter? as for me, i'm attempting to "cap" the ends of a 22 1/2 deg., stave-constructed, four part, chest lid. each end requires that six separate pie-shaped parts be mitered (shot)at 22 1/2. each part will then, should my shooting skills be worthy, be dovetailed into the ends of the four lid ends.
   jayzus, but i hope that made sense.
   eef

5. 
   RalphBarker | Dec 03, 2009 09:42am | #20

   I'm not sure that I understand the design of the box, but it sounds like there might be an invitation for unequal expansion/contraction hiding in there.

2. 
   forestgirl | Dec 01, 2009 07:35am | #4

   You'd be surprised how easily a tool can seem tuned properly, and yet not be.  That's the first thing I'd check (more below).  The other thing that is a frequent culprit is stock movement -- ever so slight, not noticeable when you're cutting, but there nevertheless (Sarge?  you'll back me up on this, right?)

   If you don't do cutting tests after you tune your miter saw or table saw, take a look a this post, fully illustrated.

   As to the stock movement, some sandpaper on the fence of a miter saw or on the miter gauge is one way to fix it.  Or clamp the stock when using a miter saw, takes a little more time, but rock solid. 

    

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 
   
3. 
   blewcrowe | Dec 01, 2009 03:45pm | #5

   Adding to what the others say, a miter joint is one of the most illusive in terms of fit because of the way wood stays in a constant state of movement.

    

   Denny

4. 
   hammer1 | Dec 01, 2009 05:04pm | #6

   Are you talking about a picture frame miter? Regardless, it's a lengthy question to answer.

   First you need to make sure all the basic woodworking fundamentals are in place. Your stock needs to be flat and straight. Small discrepancies will not allow the stock to register correctly to the saw tables or fences.

   Next you have to tune whatever equipment you are using. The blade on a table saw must be in perfect alignment with the miter ways. The miter head settings need to be correct, the miter bar has to fit the ways without any slop. A miter saw may need to be adjusted, sometimes the fence needs moving, other times, the detent may need adjustment.

   You need a good blade designed for fine cross cutting. Home Depot blades and ones that often come on a saw can be questionable. I don't use thin kerfs for accurate cuts.

   An accurate square is a must. Buy a decent 6" engineers square, it is invaluable for setting up equipment and checking results. You don't need a 45 square, most are difficult to register and many are not accurate. A bit of dust under the square will throw it off. Hold the piece up to the light and look for any light getting through the square. This takes some close attention. Putting two 45s together makes 90. There are a lot of inaccurate squares out there.

   The work piece cannot move during the cut. If you are using a miter gauge with a steel face, chances are, your piece is slipping. Don't back up after a cut, the blade may rub on the face and alter the outcome. You are going to have a frustrating time making a shooting board or a sled if you can't cut an accurate 45.

   On something like a picture frame, the opposing sides must be identical in length. Any slight variation will be multiplied by 4. Very difficult to keep equal lengths when using a shooting board. Tough enough just setting up a stop for repeating identical cuts when the end is cut on a 45, extra attention needed.

   It really doesn't take any fancy equipment. A basic saw, set up correctly along with a good blade and following the fundamentals should give perfect results without any extra work. These same fundamentals apply to all manor of woodworking joinery.

   I don't know what you have for a table saw. If it's a decent one, I'd concentrate on getting it tuned up properly along with the miter gauge. Its hard to beat the accuracy of a correctly set up table saw. The draw back is with long, large pieces.

   I'm sure we could walk you through getting your saw set up. You may want to tell us exactly what you do, every little step from where you get your lumber, how it's prepped to how you go through the entire process, otherwise we're just guessing about your approach. Is your saw tuned, have you fit the miter bar, have you accessorized it with a nonslip surface, what are you using for a blade, what brand/type saw, do you surface your own lumber, is there a particular type of miter that is giving you problems? Unfortunately, we can't watch you and one mis step along the way can effect the outcome. It's often some small detail.

   Beat it to fit / Paint it to match

5. 
   stantheman | Dec 02, 2009 02:12am | #7

   Eireannach

   Keep at it and one day it will just happen.

   I had a lot of trouble getting accurate cuts on the miter saw no matter how carefully I set up.  I had to walk through the movement and motions of the cutting process to realize how the wood pieces wood move as the blade starts contact and figured out I was not clamping the work pieces enough or in the right way to prevent them from moving during the cut.  Made a big difference

6. 
   Dave45 | Dec 02, 2009 08:22am | #8

   My neighbor retired and took up photography as a part time business/hobby. He decided that he would mat and frame his pictures and asked me for some pointers on cutting his frame miters.

   When I told him that picture framing was one of the more difficult things to do, he gave me a "Yeah, sure" look, bought a $99 bench top table saw and proceeded to destroy a couple of hundred dollars worth of really nice wood.

   AKIK, the saw is now sitting in the corner of his garage keeping dust and junk off of the floor, and he buys his frames on the internet. - lol

7. 
   Eef | Dec 02, 2009 10:17pm | #11

   e,
   with any luck at all, you will remain disturbed and unsatisfied until you find you've cut a perfect 45. if you have any addiction at all to working wood this will be true---just face it. when i made the fence on my t-saw sled adjustable things got better. short of a table saw, you're going to need a shooting board, as others are saying. i have been chasing the mystique of the shooting board for some time now. perhaps this winter break i will re-visit the whole issue....hmmm.
   eef

1. 
   Eireannach | Dec 02, 2009 10:32pm | #12

   I have a very nice table saw that I just got when I built my new shop (We just finished building our house about 5 months ago), so I am confident that if I can get the sleds made right, it will produce accurate work.  Unfortunately it's the "making the sleds right" that I am having problems with.  I finally got my crosscut sled accurate, but evry other sled I have tried is just close.  How did you make your adjustable?

1. 
   Eireannach | Dec 02, 2009 10:43pm | #14

   Thank you for the comments so far - I have learned that I need to definitely use hold-downs or clamps for my cuts - I haven't done that yet.  I will also do more practice cuts & work on adjusting my sleds & saws. 

   One question I still have though is about the picture frame miter jig.  I thought that if the cuts were made on each side of the blade, they would be complementary and fit together to make a perfect 90* corner, even if the jig was a little off of 45*.  The frame I just made did not work this way - the joints splayed out at the outside corners.  I even used toggle clamps to hold the work down.  I'm not sure how to make stopblocks on the jig to make repeatable lengths either.  I just can't seem to figure out how to attach them.  Is there something I am missing about the complementary angles thing?

2. 
   RalphBarker | Dec 02, 2009 10:47pm | #15

   A suggestion, assuming you have a really accurate square. Rather than trying to check the 45° with a combo, cut the 45 in the middle of a board, the edges of which are known to be parallel. Then, flip one side, butt the miters together, and check the 90° for square. The longer blade will more easily show minor variations from a true 90°.

3. 
   Eef | Dec 03, 2009 12:30am | #16

   e,
   the fence against which the wood rides needs to pivot at the point nearest the blade by means of a machine bolt, carriage bolt or the like. at the other end of the fence one may cut a sizable notch through which a machine bolt is tightened using a wing nut. the notch allows for back and forth adjustment. this fence may thus be fine tuned for the sneaking up process. i also make my 90 deg. sled fences adjustable as this affords me peace of mind. one must take miters and accurate crosscuts most seriously.
   stay with it,
   eef

8. 
   trimdaddy | Dec 22, 2009 09:59pm | #21

   In my mind, the most important key to miters is good equipment. I'm a trim carpenter who has pre assembled thousands of mitered casings up to 5" wide. I use a Hitachi scms w/ a 130.00 forrest chopmaster blade and 98% of my joints are flawless. On a picture frame miter, several things factor into the accuracy. obviously the pieces must mirror each other in length, the miters must be a smooth cut and they obviously have to be cut so when a left hand cut and right hand cut are assembled they create a 90 degree angle. I always cut all my left hands first, make several right hand test cuts to assure a perfect 90 and then cut all my right hand miters. Probably one of the most important keys to getting perfect miters is a good a assembly system. For my casings I use pinching miter clamps which help pull miters together even if they are not quite perfect.

1. 
   woodworker52 | Dec 23, 2009 12:45am | #22

   I have just made a miter sled and took time to make it perfect. Now I can cut miters with ease and they are right on. I will post a picture tomorrow. It is a combination of a couple I saw when cruising woodworking websites.

9. 
   davcefai | Dec 23, 2009 01:25am | #23

   I use a hand mitre saw for the few mitre joints and angled cuts I make.

   Two observations:

   1. If the saw is not locked at one of the preset points a slight sideways movement of the saw handle (say 1/2 a degree) will completely ruin the joint.

   2. If the wood moves slightly, same result.

   You might like to try one of these tools. They are comparatively cheap ($20 -50) and very effective.

10. 
    Taigert | Dec 25, 2009 08:21pm | #24

    When I was studying Fine Wood working we never really had tests per say. But we were b=given project that were mandatory. These projects were used for a major part of our grade.

    One of the projects was to make a square from a drawing with the requirwed dims. and each corner was to be mitered in a different manner. Such as ha;f lap, half bridle/tenon, biscuit, basic miter. It was much harder than most of us thought it would be. More so when you know how closely your work will be judged. We were on our own as to how we do the work.

    The first thing I did was make a miter sled and 45 deg. shooting board. They came out great!

    Taigert

    I still have that frame kicking around as a reminder.