reinforced miter joints

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I'm adding some purpleheart to slots cut into a miter joint. I ripped the slots on my RAS (I'll post pics of the setup on Boxing Day - it is quite entertaining) and am getting ready to cut the purpleheart inserts. I am looking for input as to the best grain orientation of the purpleheart. The exposed section will be the diagonal to the grain, but I do not know if it is better for the flat part hidden inside the joint to be with grain (this is what I would do left to my own devices for a little extra strength even though the purpleheart is primarily decorative) or if that hidden span should be cross grain.

The project is a jewelry box about 6" by 8" by 3" tall (maybe closer to 5" with top and bottom attached).

I hope my wording is understandable. Happy holidays to everyone!
 
Took some pictures.

Here is the setup I used on my RAS to cut the spline slots. (Why couldn't I think of the word "spline" last night for my first post?? :dunno: ) I wanted to use a climb cut for quality and I would have needed the work piece considerably more forward to have the blade fully behind the workpiece to do an anti-climb cut. As it was, I needed to put a spacer piece between the workpiece and the RAS fence in order for the rear of the cut to be fully cut through (for the spline to be flat across and not have an unfinished cut "blade curve" at the rear.

RAS_setup.JPG

Doesn't that 12" Delta FTG rip blade look scary without the guard? The blade is made by Leitz and was stolen from their excess tool department for $10 plus $5 for the professional bushing iirc (the blade, like almost all 12" stock blades had 1" bore but my saw, a Delta 33-890 has 5/8" arbor). I had to make this cut without the guard, so I thought out ahead of time how I could possibly lose an arm with this operation before proceeding. I spent Far longer waiting for the blade to stop spinning between cuts than the actual cutting or even measuring / setup.

My original post is to determine which orientation of the purpleheart is best. Please feel free to let me know if there are special words to describe these two possibilities.

This is what I mean by cross grain hidden:

purpleheart_crossgrain.JPG

And this is what I mean by with grain hidden:

purpleheart_withgrain.JPG

Thanks!
 
Mark That J-Box looks it's comming right along ,and the miter cuts look good.
I like the way the spline cut looks very well done. The rip blade looks scary without the guard? Be carefull!!
 
Either way you put it, the grain is going to be at 45 degrees to the grain of the sides, some end grain and some length grain. The direction to choose would be which ever provides the most contrast (if that is what you are looking for) The strength of the spline would be to place it with the long grain spanning across the joint.
 
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mark your nuts!!!!! using that RSaw without guard isnt safe at all.... you could have done that cut witha table saw much safer... as for the oreintation i think either will look god but like Mr simpson the strength is better to have long grain to long grain...
 
Yow! That setup looks scary!

The slots look great, though. As for the grain, you want it running across the slot - with the grain running parallel to the back edge of the slot. That way, you'll have end grain showing on both edges, and will add the most strength to the joint.
 
I may make a guard to use if I put the saw in horizontal blade mode in the future. I couldn't use the factory guard this time as it would've been in the way of the cut - something wiggles in my memory about a molder guard accessory available for this saw - might look into that too. What I did do was to turn the key to lockout the power switch (testing it each time by trying to turn on the switch) each time I rotated the work piece. Then I still made sure that my arm wasn't in contact or too near the blade (with the carriage travel knob locked to prevent motion along the carriage) while making the workpiece adjustments.

Larry, I don't have a tablesaw - feel free to bring me one and build me a bigger shop so I have room for one! :thumb:

I thought about doing this on the router table - even bought a slot cutter bit - but didn't think the slot cutter bit was deep enough for what I wanted to do, especially since I would lose depth from what I needed to do to properly align the workpiece for a 45 degree cut. With the tools I have on hand, it seemed like the RAS was the best choice. At any rate, the job got done with no injury, so I'm calling it a success!
 
Mark,

You're a braver man than I am. I would look at that set up and say to myself "no amount of joint strength is worth the risk of that spinning blade!"

The box looks good, but be careful! ;)

Thanks,

Bill
 
Sometimes setting up jigs and such are more fun than building the box itself, even when they are scary looking. At least it looks to be pretty well controlled and limited. Looks like that joint will add a lot of strength to to piece.
 
I don't have enough knowledge to speak to the strength question. :dunno:
From your description, I sounds like you took diligent measures to stay away from that exposed blade. Nonetheless, I wouldn't have done it that way. Yes, it looks scary. :eek: Meaning dangerous. :eek::eek:
That box is small enough you could have cut those miters with an ordinary handsaw in, probably, less time than it took to set up that flesh eater.
 
I have the first set of splines installed. Once the glue dries / I warm up enough to brave the cold shop again I'll go put in the second set. I thought about doing both at once, but I just cut them all oversize, but not necessarily uniform to each other and I was concerned that uneven clamping forces might result in a "thou screweth up" moment. I'm making them so that the grain of the purpleheart runs perpendicular to the miter joint glue line.

The body part is walnut, the base (not in the picture yet) is cherry, and I'm planning to put on a hinged top of ash. It is pretty obvious from the rest of this thread, but the splines in the body are purpleheart.

Regarding the splines, I am thinking to clean them up by carefully nibbling them away on the bandsaw followed by flushing them on the Ridgid oscillating spindle / belt sander using the belt followed by a final ROS treatment before applying Bush Oil for finish. Right now I have a 3 or 4 TPI blade on my bandsaw - might behoove me to switch to a finer toothcount blade for the nibbling, eh? Or, for that matter, is there a better way entirely to do the cleanup / make the splines flush?

Thanks!
 

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hey, I got the antique version of that clamp.

btw, how do you work in a shop up there on the tundra without heat?

Short periods at a time - and convincing LOML to let me bring into the kitchen small pieces clamped up for the glue to work properly. Knowing that by definition every tool in the shop is cold soaked is necessary - cold injuries need to be considered in addition to the more obvious usual shop injury risks. Small things like using plastic speed squares instead of aluminum, putting on gloves for prolonged setup procedures on cast iron surfaces and generally knowing your limitations - I had hoped to make the faces for the shelves going into my paperback organizer, but the material is rough cut and needs jointing first - I don't feel comfortable jointing with long sleeves and it is too cold otherwise. So I've found other things to work on.
 
I like the way the splines look.

As I get older, I find less and less tolerance for the cold.

3 years ago, Id play tennis outdoors year round, even in temps as low as 20. I gave up tennis, unfortunately, but I wouldnt be able to tolerate the cold either anymore.
 
Looks good Mark. What kind of wood is the box made from? I'd probably go with the band saw or just a plain old hand saw if you've got a thin piece of cardboard or something to keep from marring the box, then just sand them down the rest of the way.
 
I got a tip from wood magazine that I use alot for sawing off the ends of plugs flush without marring the piece.
I use an old sanding disc from my OS and hold it over the plug while I cut.(coarse side down)
When I needed to fill in a crack on wood, I cut a slit in the pad, and placed it over the sliver of wood (forced into crack)against the piece and cut flush with a small trim saw(flexible blade) so I didnt cut into the surface of the work.
 
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Looks good Mark. What kind of wood is the box made from? I'd probably go with the band saw or just a plain old hand saw if you've got a thin piece of cardboard or something to keep from marring the box, then just sand them down the rest of the way.

*Points up five posts*

The body part is walnut, the base (not in the picture yet) is cherry, and I'm planning to put on a hinged top of ash. It is pretty obvious from the rest of this thread, but the splines in the body are purpleheart.

:doh: :rofl: Looks like Darren didn't sleep in enough today. :p
 
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