Long Miters

[Tex]

Lately, I've started building boxes (humidor, jewelry, music, etc.). I don't have any trouble cutting dovetails and building them with that joinery. However, I wanted to try mitering and splining the corners.

I have a PM66 tablesaw and can easily make good, clean cuts. Maybe some of you can set a blade angle to get an EXACTLY precise 45 deg. angle, but, I'm not that good unless I resort to a BUNCH of T&E. I built a jig that does fairly well at cancelling out any error in blade setting. I guess, though, I never appreciated before JUST HOW PRECISE a cut has to be set up and made for all eight of them to come out right.

This has probably already been addressed a number of times, so please bear with me if I pose a previously and properly covered issue. If not, does any have a good solution?

Thanks, Tex

[Upscale]

One method that's used to obtain accurate 90° joins is to align the two pieces of wood at the exact angle you want and then slice both 45°edges at the same time with the saw blade. A simple 90° box jig using a sled on your tablesaw would do exactly what you want.

[Prometheus]

I'd suggest making a square block with a 45* block either glued to it (if your stock is always going to be the same size, or close enough to that for splining) or in a sliding dovetail. That way you've got full support on the workpiece, and your blade can stay at 90. Couldn't hurt to use some clamps to keep it in place before cutting, but once it's set up, it should be pretty consistant, and you only have to go through the trial and error process once.

[Tex]

Thanks. I might give that a try. That jig would also have the advantage of making it easy to cut spline grooves.

I built another version of a jig that gets close but I find it difficult to get EVERYTHING perfect. What I did is tilt the blade and set it as near 45* as I can using a very precise metal triangle. I make the first cut flat w/the table on one end of a piece. Then, I set the mating end vertically on the opposite side of the blade and clamped to the jig. That way the cuts are complementary and come out REAL close. But, getting that second piece mounted and clamped vertically and at exactly

90* in two axes is, to say the least, a daunting and somewhat frustrating task -- makes me love dovetails even more.

Thanks again, Tex

[Roger Haar]

Hi,

One additional thing to be careful about is the the front and back pieces (and similarly the two side pieces) pieces must be the the same width from 45 degree cut to 45 degree cut. For example when making picture frames, all of the corner cuts can be perfect 45's, but if the top piece is 1/16" longer than the bottom, things will not fit. Until I understood and took care about this I had an awful time. I would check and recheck my angles, and every one looked good, but a dry fit showed they did not fit together. I would carefull sand the angles eliminate any gap in the joiint, but the if the pieces matched up on the inside of the corner, one would be a tad long on the outside.

My suggestion is you get a 45-45-90 draftsman triangle, and this should let you set you blade to a 45. Be carful to not get avoid the teeth that stick out beyond the plae of the blade. Then be very careful about widths. A sled with a stop can help.

Thanks Roger Haar Tucson

****************************************************** Prometheus wrote:

[Teamcasa]

"Tex"

Miters require time and exactness. I have found that to make exact, very precise miters, several thing need to be considered. Board width and thickness, precise lengths and accurate cutting. For me, it just too many variables. When I need an exact miter, I cut the piece long and then using my 12" disk grinder, I adjust, sand, fit and adjust again until the fit is perfect. This works well up to 5" or less. For longer miters, I take the time to set up the tablesaw for precise 45's. I always setup using a miter sled and set the angle by measuring the sled to blade angle - not tablesaw to blade.

See picture below

[Prometheus]

Yeah, miters are an exacting joint, but they look nice, and work well for lots of things.

If you're just looking for a change from the dovetails, though, have you tried playing with box joints? I just got around to making a jewelry box with them, and it took about 5 minutes to make the jig, and they look pretty slick, especially after rounding all the corners.

[foggytown]

I do a lot of the same type of work you do. I never could make a decent dovetail so I used box joints to begin with and made a jig to go on my router table. These worked fine but I wanted an alternative so I got a cheap one of these:

a belt&disc sander you can make very accurate 45 (or any) degree miters by sanding them. What I do for flat sides, tops, etc is first make certain that all the corners are 90 degrees. Then I set the top resting table to 45 a degree tilt using a square, draw a line about

1/4" above the bottom of the side I want ti miter and sand down to that line using the belt. For trim and any long pieces I want to miter the ends of I use the miter fence on the lower table and push the end of the piece into the disc. It all takes a little practice and a steady hand but the miters are clean, smooth and above all accurate. This machine also makes removing very small amounts (like 1/16") very easy. I couldn't do without it now.

FoggyTown

[Jay Pique]

A little fine tuning with your burnisher will help a bit too. damhikt, my joints are always perfect.

JP

[Tex]

I haven't tried box joints. I've always liked the way they look, though, on utility-type boxes but will have to give them a shot with some good looking wood.

FoggyTown, Thanks for your solution of using a belt/disc sander. I hadn't thought of doing it that way. Since that's a piece of equipment I just haven't gotten around to, perhaps you've given me the reason why I can't do without one any longer.

As far as dovetails, I have a Leigh jig. Thru and half-blinds are pretty easy once you get everything set up and make a couple of practice runs.

Thanks again guys, Tex

[Prometheus]

I was a little leery of them myself, as I had seen a lot of them with kind of bulky fingers, and I don't care for that much, but I made my jig to work with one pass of a diablo blade. 3/32" fingers in contrasting woods (I used lacewood and maple for the first one) looks awfully sharp, and fairly classy- kind of like a really high-end cigar box. (Which is what made me think of it when you mentioned humidors)

They're easy to make with the jig- easier than dovetails, and the jig is nothing but a scrap of mdf screwed to the miter gauge with a finger the size of your slot to align it.

[Ranger Paul]

Tex,

Getting "perfect" miters using a disc grinder sounds a bit challenging to me. I have a hard time believing that something as primative and coarse as a disc grinder can deliver true precision. Of course there are people with photographic memories and perfect pitch and 20/10 visiion too I suppose. But for normal human beings I would be more inclined to believe a lot of lumber would end up in the scrap pile trying this method......or....... my project would become gradually smaller, and smaller, and smaller.

Check out this contraption:

the video clip demonstrations there.

I have had a SmartMiter Sled for 2 1/2 years now and my miters are "perfect," I'm talking dead nuts absolutely perfect, every time, in seconds. Once you have the set up done, 20 minute chore, cutting perfect miters takes about as long as pushing the work piece through the saw blade. Cutting to long points, short points, setting the length stop ONCE and getting mirror cut pieces. Check out the link and watch the videos.

RangerPaul

[Tex]

Thanks, RangerPaul,

Although I hadn't considered myself abnormal (others probably even express that behind my back!), I'm very lucky to have the 20/10 even after a bunch of years on this good earth. As for the other attributes

- FORGET IT - I didn't get those.

I took a look at the web site. I haven't been thru all their stuff but it does, indeed, looks interesting. I want to be able to cut 8", or so, miters so I can build boxes (VERY ACCURATE corners -- as you say dead- nuts ON). Can this device do that or is it restricted to smaller (i.e., shorter) cuts (e.g., molding, picture frames, etc.)?

Thanks again,

Tex

[CW]

You could do what you want with this thing and a 24" (blade size) table saw. Otherwise, tilt the blade and do it. If you have trouble tilting the blade accurately, take a look at Ed Bennett's Tablesaw Aligner. It does angles well.

[Teamcasa]

"Ranger Paul"

Not really. I get absolutely perfect miters both large and small with my 12" Jet Disk sander. Believe me, it works and its much easier to make the perfect this way. See picture below

know I sent this link before but in case the server dropped it ~) Dave

[Tex]

Thanks, guys. This and info from other posts are exactly the kind of info I was looking for when I started this thread. Ain't it a shame we don't live 'down the street' from each other so we could just drop by and chat rather than having to do it via computers? OTOH, you just gotta appreciate the Internet that lets us find guys that are doing similar things.

Y'all have a great weekend! Tex

[Upscale]

disk sander for your mitres. However, since I've never tried it that way, I don't have any choice except to take you at your word. It's certainly something I'm going to investigate the next time I have the use of a disk sander.

[Tim Taylor]

Ok, I can see it happening. The miter gauge turned backwards with the clamp on it, but how is the small piece of angled walnut? playing a role? Is it attached to the miter gauge?

[Prometheus]

I'm not too surprised- I've used my disc sander for this as well. It's just more work than cutting it dead on the first time. But when I just had a little table saw that was hard to adjust properly, the disc sander was invaluable.

[Bob Moos]

Here's a couple of tips I've recently come across for helping with mitre joints:

1) If the joints have opened up only a little bit, but enough to notice, you can bring them back together by rubbing/rolling a screw driver's shaft over the joint. This will round the edges a bit, but depending on what you're doing, that might be okay. I've used this trick a couple of times and it works pretty well. 2) Another thing to do to help with the joining is how it's clamped. Instead of using right angle clamps and the like, you could instead clamp them using the method mentioned at this page[1]. I've not tried this one myself, but intend to give it a try. [1]: