Can I put biscuits in full length dados?

[Bobby O'Neal]

I feel like I've seen Norm do this, but I don't really remember for sure. In the case of joining case pieces, would it work to just cut a full length dado in the mating parts and drop biscuits in it? I dont own a biscuit joiner and am not really wanting to obtain one right now.

Thanks all.

[Callan Campbell]

I think you're describing Norm and others who use something along those lines to attach a face frame to a cabinet. Single,. continous groove[slot cut by biscuit joiner or router] cut into the cabinet, with a few cuts made in the face frame where they're needed or allowed, to drop the biscuit into. Then the face frame is glued to the cabinet. I could have it backwards, as it's been a while since I've watched that technique too.

[Prashun Patel]

(I'm not a pro), but yes, you can certainly do this. The only reason NOT to do this is because you will have a kerf visible on the ends of the joint. Instead of biscuits, you can also use a single long spline. This will add marginal strength vis-a-vis biscuits, and will plug the end of the kerf.

[Rod Sheridan]

As Callan and Prashun have indicated ou can cut a continuous or intermittent groove using other tools such as a router with the correct cutter.

On the rare occasions that I use biscuits, I cut the grooves on the shaper............Rod.

[Ken Garlock]

Hi Bobby.

I would not use biscuits for anything more than alignment of two pieces. IMO, the better solution is to make the continuous groove en each piece, and use a spline that runs the length of the pieces. I used plywood as a spline to hold the aprons to the top when I built my workbench.

[Howard Acheson]

It would lead to a very weakened joint. Most of the slot would not have either wood or adhesive in them. While the specific points where there were biscuits would be strong, the rest of the slotted area would be weakened by the slot.

What are you trying to do? Biscuits mostly are not necessary for joints. The adhesive is stronger than the wood so biscuits add little or nothing to strength.

[Paul Symchych]

Agree with the others. Biscuits add no strength while cutting a spline out of the same or some proper wood is as quick, stronger and cheaper.

[David Weaver]

Not only would they weaken the joint, but they could also telegraph through the surface of the wood. No reason to use them if your clamping is adequate.

[Ira Matheny]

If using continuos dado, try spline made using tempered hardboard. Be sure spread to glue both pieces. Very strong, long lasting, and significantly less costly!

[Bobby O'Neal]

Sounds like I may try the spine idea. I'm building a wall unit that will be painted plywood mostly. Some hardwood involved for frames of doors, drawers. These particular joints will be corners, butt jointed or otherwise. I'd thought about maybe finger joints just for added glue surface. I'm still drawing, so its all up in the air still. Thanks for all the input so far.

[Peter Quinn]

I have seen the continuous slot used by "Nahm" and others, he didn't make that up or pull it from thin air either. I've seen it used for lateral alignment between a plywood carcass and a solid wood face frame where you might want a quick spot to drop biscuits where you like during assembly. I suppose some find it expeditious because rather than make witness marks on both parts to align the two biscuit slots you just throw in a long kerf and put the biscuits where ever you would like. Usually its milled on the front edge of the vertical plywood parts and on the backs of the stiles on the FF's. I don't personally find it necessary if you have the clamps simply gluing the FF to the carcass is probably stronger or a least as strong and eliminates that additional step. But, you need a lot of clamps with glue alone. I like the spline idea better. I'f I didn't have a biscuit joiner and were looking to buy a joinery tool to make plywood case connections for basic cabinets I'd rather have a pocket screw jig. In plywood its a great way to make just about every connection I'd use a biscuit for. I love pocket screws for connecting FF's to cabinets, though you have to think about how you build to hide the screws.

Anyway, you can probably skip buying a dedicated "biscuit" bit for the router and just use a generic sot cutter or even a TS kerf to make a spline slot for such connections. My favorite is a 1/4" dado or slot cutter with 1/4" baltic birch splines. They are very strong and easy to make.

[John TenEyck]

For joining faceframes to the box Norm's method works great. Actually, it's not Norm's method - he gave credit where he saw it used - at a cabinet shop. A continues groove is cut in the cabinet parts and bisquit slots where desired or needed in the back of the faceframe. It's fast and accurate, as the bisquits keep everything in alignment during glue up. Anyone who thinks it's not strong enough should try removing the faceframe after the glue has cured.

[glenn bradley]

+1 on a spline.