Splined Miter Joints using only Festool

[enderw88]

A few projects I have in mind use miter joints with visible splines for decoration and a bit of strength.    My description is probably poor so here is a simple sketchup picture:

[attachimg=1]​

All of the methods recommend a jig that runs the finished miter joint over a table saw blade then fitting the splines.
As I do not have a table saw, and do not plan on procuring one anytime soon, I want to figure out how to do this with my TS-75 and MFT-1080.  Given that the different pieces I will be doing this to are different sizes, and have one or more splines I need a solution that is somewhat flexible.

I won't need to do this more than a few inches down the side of the miter joint so I was thinking of building a jig that would hold the piece to the side of the MFT and run the saw down the guide rail over the edge.  It will be a bit slower to set up than on a table saw, but I can't think of any other gotchas.  Has anyone else ever done this, or have better ideas?

 

[Eli]

I think you'd need something like the rig in this thread (only obviously not 20' long!), you could use it for glue-up and then run the saw across the top of it for your spline grooves.

 

[Lancashire Fusilier]

What about cutting the spline grooves before assembling the mitre joint? If you put both pieces back to back, clamped and then cut it would eliminate any fancy jigs.

 

[ROb McGilp]

Hi Craig,
Don't know how thick you want them, but these were done with the good ol' Domino.

Regards,

Rob

 

[Mirko]

Craig Earls,

Use the MFT but remove the guide rail support, leaving only the hinged one on, adjust the guide rail so it hangs over the edge of the MFT.

Use a piece of wood scrap to support the guide rail, keeping it from flopping around, make sure the scrap wood is thicker than the spline depth, make sure the hinged mount is adjusted to the thickness of the scrap. Use one of the Festool clamps, passed through a hole in the MFT to secure everything in place.

You now should have the MFT with the guide rail hanging off the front edge, supported by a makeshift support.

Now you can use the extrusions and the Festool clamps to position the parts you plan to cut, by placing them up to the underside of the guide rail, add a stop block for repeat cuts, I would clamp as many parts that will fit in the clamps, then pass the saw over the parts to cut the spline groove.

Mirko

 

[Eli]

What about cutting the spline grooves before assembling the mitre joint? If you put both pieces back to back, clamped and then cut it would eliminate any fancy jigs.

True that.

 

[Matthew Schenker]

Craig,
I've done this sort of thing on the router table using a thin blade with the piece mounted in a "V"-shaped holder, as shown here:
From Taunton
From Woodsmith
From Gary Rogowski

I've tried these concepts, and made my own jig for the purpose -- with varying degrees of success.  Like you, I've been searching for the perfect method!  I'd say the Domino offers the greatest hope here.

Matthew

 

[enderw88]

Craig Earls,

Use the MFT but remove the guide rail support, leaving only the hinged one on, adjust the guide rail so it hangs over the edge of the MFT.

Use a piece of wood scrap to support the guide rail, keeping it from flopping around, make sure the scrap wood is thicker than the spline depth, make sure the hinged mount is adjusted to the thickness of the scrap. Use one of the Festool clamps, passed through a hole in the MFT to secure everything in place.

You now should have the MFT with the guide rail hanging off the front edge, supported by a makeshift support.

This is where I am headed.

Now you can use the extrusions and the Festool clamps to position the parts you plan to cut, by placing them up to the underside of the guide rail, add a stop block for repeat cuts, I would clamp as many parts that will fit in the clamps, then pass the saw over the parts to cut the spline groove.

Mirko

What extrusions are you referring to?

 

[Mirko]

Craig Earls,

The aluminum extrusions on the table that the clamps slide into.

Mirko

 

[enderw88]

Craig Earls,

The aluminum extrusions on the table that the clamps slide into.

Mirko

Duh... Thanks!

 

[Tinker]

I must be a bit dense.

I have looked at every detail and explanation along this thread.  there are all sorts of descriptions for mitering boards and joints together and with various ways to do splines.

Some really great ideas, but as far as I can figure out, not one pic, demo or explanation has addressed the original posters question/problem.  I was very interrested in hoping to find the answer, as I have plans to do the same type of joints for a jewlry box for my daughter.  I have discarded my Table Saw and I need to work out a solution.

I think Matthew has the solution by using the domino.  I keep trying to find ways to avoid getting that toy, but you people keep hammering away at my resistance  :
Tinker

 

[Tinker]

Upon review,  I think Mirko has the solution.  I had to go back and re-read, but I think the only way to do the splne cuts with the Festool saws is to cut the grooves in the pieces, not in the assembled joints as I (and others) have done with the table saw.

I will try Mirko's method. After study, it actually seems very simple
Tinker

 

[Eli]

I think it was Rob who did the splines with Domino. I thought you already HAD one of those glorified angle grinders. What'd you end up buying when you went down to the store with th' missus?

 

[Tinker]

This is "Billing Weekend"  Spending much of day printing billing for recent sno plowing/sanding.  More snow tonite means SLWMBO will have bigger spnding mood when we finally get to toy store.  sometimes, a FOG'er just has to go with the flow  :
Tinker

 

[poto]

If my mental geometry is accurate, the difference between Mirko's method (method 1) and cutting the spline groove when the parts are assembled (method 2) is that method 2 will give a void that can be filled with a flat strip of wood (the spline), whereas method 1 will have to be filled with a piece that has a 90 degree corner on the inside. Method 1 will require a bit more fuss in making the spline that will fill the void, and you'll have to be careful about grain alignment in the spline to make sure it runs the right direction. Method 2 is harder to cut with Festools, but simpler to fill with the spline itself (i.e., no voids). Does this make sense?

 

[Brice Burrell]

Poto, you are right. The harder way, but would take care of the void that Poto is talking about is to cut the pieces together with a jig. Maybe something like this.

 

[Eli]

That was why I thought modifying Eji's column rig would be the best way to do it, you'd get glue-up and cut rig in one package. You could even make a rig that was twice the length of the box's height and do two corners at once, and cut the workpiece in half to yield two L-shaped pieces with opposite corners cut for splines.

You'd have to figure out how to do the other two sides after assembly, maybe by clamping the rig and box to the side of the MFT so the bottom corner can hang below.

For that matter, why couldn't you build the box and clamp the top (or bottom) flat against the front rail of the MFT, the corner to cut clamped flush with the top, with a guide rail positioned L to R across it. You could clamp a board the entire front length of the MFT 'under' the workpiece, to support the rail.Release and re-clamp for each corner.

 

[enderw88]

For that matter, why couldn't you build the box and clamp the top (or bottom) flat against the front rail of the MFT, the corner to cut clamped flush with the top, with a guide rail positioned L to R across it. You could clamp a board the entire front length of the MFT 'under' the workpiece, to support the rail.Release and re-clamp for each corner.

Yeah,  after reading everyones input, this is what I think I will attach to the side of the MFT:
[attachimg=1]

 

[Brice Burrell]

I think you got it, nice solution.

 

[Eli]

I didn't see that coming.

Will the point of the box (work) end up flush with the top of the MFT?
Do you then clamp inside the jig to hold the box?

I think you could just clamp the box itself right on the side of the MFT with a board between it and the extrusion, mark the angle on the board (to line up the box for splines) and flush the board to the MFT top, lay a short rail, clamp that, and geter done.

But that jig looks like it'll work great.