How to cut domino into thicker board

DA-PNW

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Newby question here. I'm making a table with 2.5 inch legs. Using a DF 500, how do I cut (vertical) domino slots in the center of the legs? To my understanding the largest distance from the face plate to the center of the cutter is the 30 mm on the height gauge. With the face plate referenced against a side of the leg, that 30mm wouldn't reach the center of the 2.5 inch/63.5 mm board. It would be close but not centered. What's the general modus operandi to get to center on thicker boards? Thanks
 
Thanks for the info. That's seems like a viable option. I might also end up not positioning the apron in the center of the legs and make the outside offset smaller, in which case I could use the face plate as a reference. I appreciate the reply
 
Another way to do it if you want centered mortises is to use the base rather than the fence for registering. In this method, you raise the machine with a block or platform such that its cutter's center point aligns with the center line of the leg.
 
I don’t use a Domino, but back when I was using a biscuit joiner regularly, and that situation would come up, I resolved it this way:

I used 2 biscuits per joint. First banking on one side of the board and then banking on the other side. I would leave even spaces between the biscuit and the edges and between the biscuits. It made a strong joint, and was fast and easy.

I would imagine that the same would hold true for a domino machine. You are using different floating tenons, but the process is very similar.
 
Yes, the technique you described can be done with the DF500 by registering the fence on either reference face.

But unlike biscuits for which one may not provide the strength needed, with dominoes, if one domino is enough, no one will put two there. The OP is looking for a way to mill centered mortises, not double ones.
 
Yes, the technique you described can be done with the DF500 by registering the fence on either reference face.

But unlike biscuits for which one may not provide the strength needed, with dominoes, if one domino is enough, no one will put two there. The OP is looking for a way to mill centered mortises, not double ones.
But if it is faster, simpler to execute, it still makes sense to me. Of course I don’t have a Domino-mindset.
 
But if it is faster, simpler to execute, it still makes sense to me. Of course I don’t have a Domino-mindset.
You still missed the point, eh? The method you suggested doesn't cut centered mortises.

This is what the OP wanted: "What's the general modus operandi to get to center on thicker boards?" (bold mine)
 
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You still missed the point, eh? The method you suggested doesn't cut centered mortises.

This is what the OP wanted: "What's the general modus operandi to get to center on thicker boards?" (bold mine)
Yeah, I don’t get it.

Twin tenons are an age-old joinery method and stronger than a single tenon. And if it is faster and easier than a single tenon, then a no brainer to me. Much easier with a Domino machine, and yet history shows that when greater strength was required, twin tenons got used.

It has double the face grain surface area, and puts the emphasis on pull-out strength rather than than bend-then-break strength.

So, yeah, I don’t get it. Why put extra effort to end up with an inferior strength joint?


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The stock on BOTH mating pieces must be thick enough to use twin tenons. In the case of dominoes, we also want to follow the "one-third" rule, meaning if one domino is good enough, two may even weaken the joint if the stock thickness doesn't meet the "rule."

Here is a simpler way to see that: Would you use two screws to put something together if one screw is strong enough? You wouldn't, right?

It is not uncommon that some biscuit cutter users look at the domino machine as just another biscuit cutter.
 
The Op didn't say he is not using two centered dominoes (which are double dominoes, not twin dominoes). In a double tenon joint, they are usually centered. And if that's the case, the OP would still need an answer on milling centered mortises.

Of course, they (the OP) could still settle on a twin tenon, but then the inquiry would be different from their original inquiry and our responses would be different, too.
 
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The Op didn't say he is not using two centered dominoes (which are double dominoes, not twin dominoes). In a double tenon joint, they are usually centered. And if that's the case, the OP would still need an answer on milling centered mrotises.
We take a chance when we attempt to answer these queries. Probably shouldn’t bother until more parameters are provided.
 
Yes, the parameters given are limited, but that's usually the case when people ask for advice. We have had countless posts like that on this forum. When I give a response, I try to address what is being asked, in this case, how to center mortises. Nothing more and nothing less.

Yes, some may ask for more info. before making any suggestions. We all have different styles, which is a good thing.
 
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