(Yet another) Domino 500 jig...design input/question

[jdm5]

Hey all,

This thread prompted me to investigate building a benchtop domino jig, both to hold the domino and the material to be mortised.

I liked the design Carmonius Finsnickeri (Youtube video) came up with, but realized it's not height adjustable.  I.e. I frequently work with 1/2" and 3/4" stock, and the 10mm cutting height is fine for 3/4" but not so much for 1/2". 
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Would be curious if anyone has ideas to enable height adjustment on this.

I came up with three:

1. Cut a pocket to recess the Domino machine in that design for the thinnest stock size (say 1/2"), then shim it up to other desired thicknesses (i.e. have a shim ready for 3/4" thickness, fabricate other thicknesses as needed).  Will this be accurate/repeatable?
View attachment 2

2. Have multiple jigs for multiple thicknesses...seems crazy duplicative / wasteful / $$$ but probably most accurate and minimizes setup time and human error...doesn't seem reasonable

3. Have interchangeable bottom pieces (that holds the domino) for variable thicknesses - i.e. have one thickness cut for 1/2", one for 3/4", be able to fabricate more as needed.  Use Domino connectors or something like that to connect the two pieces of the jig .  Concern about accuracy with the connectors (getting repeatable heights).
View attachment 3

Would welcome any feedback/thoughts - thanks!

 

[Bob D.]

Couldn't you just place a 1/8 shim under the 1/2" material?

 

[Crazyraceguy]

That popped up here about a week ago.

 

[afish]

If you shim under the 1/2" then the domino would be even closer to the edge of the 1/2. No?

 

[jdm5]

Yep - missed that.  Thanks!

 

[Bob D.]

If you shim under the 1/2" then the domino would be even closer to the edge of the 1/2. No?

No, you'd be shimming to get the center of the 1/2" material to the same center as the 3/4" material.
So when you make the mortise it will be (close to) centered.

 

[afish]

Quick and easy method would be build the jig from 2 layers. One layer would be full size. the top layer that would have the dovetail groves cut in would stop short where the fence is. this would lower the domino by whatever thickness the top layer is. say 3/4" for example.  then you would just need to have blocks of different thicknesses to adjust the height of the domino.  Obviously one would be the same thickness as the 2nd layer this would cancel out any deviation and result in basically what you have now flush with a 10mm to center of cutter height . But by having thinner boards that the domino would mount to, would lower it and center it better in thinner stock or vise versa.  I would also probably make base plate boards 6-8 wider than the domino so they could screw on to the domino and then the domino and plate would attach to the jig either with some star knobs or toggle clamps this would make attaching and removing easier.  It would also give the jig more rigidity after routing in all the grooves. 

 

[afish]

Yes, bob is correct.  shimming under the material will move the cutter more towards the middle of the stock.  My brain isnt fully awake yet. 

 

[afish]

But the double layer top is probably better than trying to shim parts individually each time if its more than a one off situation.  I would prefer to have one setup and burn through the parts quickly.  If its just a once and awhile thing then shimming the parts would work.  It would also depend on how precise you needed or wanted the domino centered. 

Here is a quick sketch up what I was saying.  I didnt get crazy with any details or scaling just a quick overall visual idea. The thinner the stock being mortised the thinner the mounting plate.  If you have a planer it would make it easy to make different and precise thickness mounting plates. otherwise you would be limited to standard thickness and adding washers if needed.  You could add some adjustment screws under the mounting plate for precise adjustments but you would need a screw in each corner and make sure they are all the same height so the mortise wasnt at an angle.  However in some applications it might be handy to angle the mortise... Hmmm. lots of possibilities.

 

[Svar]

Your option #1 is by far the best. Just carefully select shim material: flat, uniform, rigid.

 

[jdm5]

Thinking about it more - I agree with [member=73094]afish[/member] and [member=15585]Svar[/member] - will go that route.

I can share cnc plans and details if there is interest.

 

[afish]

Not sure I would use it enough for what I do to justify building and storing it, but I would love to see the finished product when you are done.  That being said Having plans available is never a bad thing. 

 

[ChuckM]

The proposed jig might be useful for small pieces (small registration surface) and miters. For added strength and durability, I would make the shims of the desired thicknesses roughly the width of the jig's base, not just as a pocket.

 

[Vtshopdog]

For shim, how about aluminum plate (of whatever thickness is appropriate for your stock)  cut to dimension of Domino base, drilled, countersunk and attached with flathead machine screws to existing threaded holes in domino base. 

1/8" is common stock increment, you could fabricate multiple 1/8" shim plates as needed and stack them with appropriate matching length machine screws.

 

[Ola C]

Hi everyone, Ola here from Carmonius Finsnickeri. Nice that my jig is up for discussion.

As I say towards the end of the video, I either place a shim under the Domino (for thicker stock) or under the workpiece (for thinner stock) to acchieve a close to center cut. One fine thing with this jig is that the joints don't have to be in the exact center of the thickness as you never flip the parts upside down. With that said the shims doesn't have to be so exact that the locate the joint in the exact center. I don't cut new shims very often, strips in say 60mm width (and as long as the jig is, 300mm something) suits most operations. The shims under the Domino are simple rectangles that matches the sole of the machine.

For shimming I typically use plastic sheets, like acrylic, in different thicknesses.

p.s. You gave me something to think about though about adjustable height, that's good because I just finished my latest jig and need a new challange [laughing]

 

[afish]

[member=71921]Ola C[/member] Thanks for making and posting your design here to share for others.  Its a great concept and design.  The stuff I do hasent really required such an item but Im sure it has helped others.  One other thing I would probably do "if" I made one is make 2 of the triangle stops that can be installed on both sides of the workpiece to sandwich the piece and use a toggle style clamp. That should greatly speed up the work flow while still providing really good secure placement of the part if you have a lot of pieces to do.   

 

[Ola C]

[member=73094]afish[/member] I totally agree with you if it's large volumes to do but other than that I'm not a fan of toggle clamps. Takes time to adjust to correct height and reach and pressure and they put large torque between the parts and risk to bend the jigs. Of course it depends a lot on what kind of work you do, but for what I'm doing all my toggles including Bessyes autopressureadjust whatever they are called are put in a drawer since many years...but I never do large volumes of anything.

 

[huntdupl]

[member=53094]jdm5[/member] nicely done. Fantastic channel btw, excellent content. That superjig [jawdrop]

 

[jdm5]

[member=62776]dupe[/member] no I need to be clear, I'm just building what [member=71921]Ola C[/member] built and it's his channel - he deserves full credit both for the idea and video.  I'm just reproducing it (or my own variant of it).

I'm using a CNC so will be able to share the design if Ola is ok with it [I was going to reach out when I had something to show] - I've cut 2 prototypes, 1st I found some mistakes, 2nd I had a power blip and CNC reset...will hopefully finish this week (I hate it when work interferes with hobbies!).

 

[Ola C]

[member=53094]jdm5[/member] sure no problems go ahead. Would appreciate if you link to my youtube if you plan to share the files.

[member=62776]dupe[/member] Thanks! The Superjig is fresh from the drawing board, just finished the films. Is there a forum subcategory where it would be ok to upload it here or it's pure Festool subjects allowed?