The quest for a perfect miter joint

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I am making a set of three stacking tables. Each table will have a 2 1/2" wide piece of mahogany to trim the center rectangle of curly maple (still deciding on the center). I got my technique down to get nearly perfect miter cuts on my SCMS but the saw makes a slighly rough end cut that I would like to be able to smooth off to get the best possible fit.
I tried to clean up the cuts with the sanding disk part of my combination sanding disk/belt sander. It is a Ryobi I got for $99 at Home Depot a couple of years ago on sale. Well, now I know why it was only $99. I could never get the thing to sand the cut perfectly smooth. No matter how I fiddled around with the (very cheap) miter gauge on the sanding disk, it always sanded one end of the cut more than the other so I got a slightly rounded surface. I guess $99 was TOO much to pay or more realistically, I shouldn't have gotten it just because it was cheap.
The cuts aren't bad but I can't think of any way to sand the rough ends of the cut to get an even better fit. Have any of you solved this problem?
TIA.
Dick Snyder
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"Dick Snyder" wrote

Got a table saw?
Consider making a "miter sled" like the one on the Jig and Fixtures page of my website.
Big plus is the _exact_ "45 degree" angle basically becomes a moot point (particularly with the usual widths of picture frame miters) because the order of cut, using an established 90 degree corner to build the sled, insures complementary angles, and the jig allows you to use a stop block to insure the sides are all cut the same length.
These two concepts combined make miter cutting a much easier task, with little or no tweaking.
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I do have a table saw and I also have a miter sled I made. Unfortunately the miter sled I made does not have stop blocks. I made it for cutting one end of a piece of wood and it does a fine job at that. I may make a better miter sled like yours that has stop blocks but since my SCMS is doing a perfect cut now, I just want to find a way to smooth the cut ends of the wood while not losing the perfect 45 degree cut. Thanks for the reference to your sled. I like the way you did it and will probably copy what you did.
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"Dick Snyder" wrote

Perhaps a better blade on your SCMS so further sanding is not necessary? I have a Forrest Chopmaster on my Makita and resultant miter cuts are glass smooth and glue ready, no sanding necessary.
With miter cuts, if I don't get the quality I need on the initial cut, sanding seems to add more problems than it's worth. I hope your luck is better than mine in that regard.
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Excellent point on the blade Karl. I have a Forrest Woodworker II on my table saw and it was absolutely worth the high price I paid for it.
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While I am at it, if I do copy your sled are there any improvements you would make if you did it over again?

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"Dick Snyder" wrote

None that I can think of. It does precisely what it supposed to do - give you perfect miters - and it's damn hard to improve on perfection. :)
The most important part of building it (other than getting the miter slot runners parallel), is to be anally precise about insuring a perfect 90 degree angle on the plywood board that makes up the two opposite "fences". I was lucky in finding a factory plywood edge that was nuts on, but it really pays off down the road to be overly picky about this one factor.
Do so, and even if you are a little off in placement of this part on the sled, you still have the complementary angle principle working in your favor when you cut adjacent miters on opposite "fences".
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Another argument against the sanded joint .. .. I was taught early on the NEVER sand a surface that I expected to glue. The dust fills the pores, and affects the strength of the joint.
Swingman wrote:

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Dick Snyder wrote:

Put a sanding plate on your saw.
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On Fri, 02 May 2008 13:37:23 -0500, Swingman wrote:

Soo... how come the 'point' of the ply triangle hasn't got a blade kerf cut into it? Never been used, or does it just not show up in the pictures?
Or am I missing something about how it should be used?
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It has a kerf, a bit hard to see but it is there. Additionally there is not much need to cut much past the actual stock you are mitering so the kerf need not be very far into the "point".
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"PCPaul" wrote in message

Yeah, I just made the sled to hang on the wall of the shop and look pretty ... art, doncha know..

A better monitor?
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On Sun, 04 May 2008 08:54:19 -0500, Swingman wrote:

That's kinda what I figured... ;-)

Well, in my defence the picture had to be squeezed an awfully long way down the tubes.
Don't mind me, I'm just jealous. My 'shop' is a UK-sized one car garage - about 17'x8'. And it's not all for my sawdust generators either.
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"PCPaul" wrote in message

LOL ... that'll indeed make a difference. (actually, if you look closely you can see the "vanishing magic kerf" in the second picture. It appears to be hidden by the edge of the plexiglass guard in the first picture. As Leon said, there is no need to cut much further past the "point", so it's not like a regular cutoff sled in that respect.)

BTDT, and in the UK, AAMOF ... (built some of my "just married" furniture in an 8 x 8 garden shed in Staines, Middx).
Now, I've got about twice that space (18 x 18), which seemed like a luxury in comparison ... for all of about ten minutes. I have plans (depending upon whether, in retirement, one prefers eating to having a bigger shop.) to build a 20 x 36 shop. I'm sure it won't take long to make even that seem inadequate.
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How big is your sanding disk?
I usually use the 12" disk sander and clamp a guide board to the cast-iron table at 45 degrees to the disk. Then just keep the workpiece tight against the guide board. Don't bother with miter gauge at all. You're doing pretty light sanding, I hope, so you don't need to press hard or you'll burn the end.
scott
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writes:

For $99 there was no cast iron table and no 12" disk. It was a mistake to get this thing!
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On Fri, 02 May 2008 17:43:40 -0400, Dick Snyder wrote:

You can get a 10" sanding disk for your table saw. Get the one with one side tapered.
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Larry Blanchard wrote:

but don't use the tapered side to try and square up anything - the taper will assure un-square joints.
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Doug Winterburn wrote:

To the contrary, the tapered side is what is meant to be used. One has to tilt the arbor so that the taper is vertical; doing so means that the wood can be fed into the disk without catching on the edge of the plate. Additionally, the taper provides only one point of contact for the wood which means all sanding will be linear and parallel to the direction of feed rather than circular.
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If you use the tapered side with the arbor tilted you end up with a "Hollow Ground" surface.
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