Dados vs. biscuits?

[Ryan_M]

Doing a build and the layout resembles this type of construction. I'm not arguing that buttt joints aren't good enough, I want to use either of the mentioned techniques to aid in alignment when the frame goes together but the added strength doesn't hurt either. Most people I see building this type of box use dados. I don't have a dado blade, been meaning to get one some time but a good one costs $$$. Any reason I can't use biscuits to get 'as good' results?

[bobbarkto]

Biscuits will work nearly as well IME.
There is a little bit of sideways slop until the biscuits expand enough to grip, and they don't hold the pieces together unclamped quite as solidly as dados, but otherwise they work ok. Better than nothing.

[dougjohnson]

Doing a build and the layout resembles this type of construction. I'm not arguing that buttt joints aren't good enough, I want to use either of the mentioned techniques to aid in alignment when the frame goes together but the added strength doesn't hurt either. Most people I see building this type of box use dados. I don't have a dado blade, been meaning to get one some time but a good one costs $$$. Any reason I can't use biscuits to get 'as good' results?

A router in a table or with a straight edge guide does dados just fine. You can also do multiple passes with your table saw blade.

Frankly, I'm not fond of biscuits. A good dado joint is stronger and easier to align. I use my biscuit joiner once every couple of years. If I were doing it over, I'd buy the dado blade instead. -- Doug

[Æ]

Do you have a biscuit joiner?
Rabbets are easier to do. You don't even need a dado blade, but one is nice to have. There are inexpensive dado blades out there.

Doing a build and the layout resembles this type of construction. I'm not arguing that buttt joints aren't good enough, I want to use either of the mentioned techniques to aid in alignment when the frame goes together but the added strength doesn't hurt either. Most people I see building this type of box use dados. I don't have a dado blade, been meaning to get one some time but a good one costs $$$. Any reason I can't use biscuits to get 'as good' results?

[LouC]

I've used both. For 3/4" stock or thicker, biscuits are my favorite. By the time I get a dado blade set up, (or make multiple passes on the table saw) I can have the biscuits cut. It takes longer to lay them out then to cut them. On 3/4 or thicker, you don't even need the fence on the plate joiner. You can use them on mitered cuts too. If you are careful cutting, you can even straighten out mildly warped stock.

Dados & rabbets have the advantage of no additional supplies (biscuits). I like them for thinner stock -- especially with a brad nailer.

[terryo]

Biscuits are, IMHO, much misunderstood. I see them as an alignment aid, although I suppose they may add a small measure of strength. I use them myself on all sorts of projects and can offer a tip to those who have had trouble using them.

When cutting the slots for the biscuits use your tablesaw as a flat surface to guide the biscuit cutter. The fence makes a good backstop and with a couple of clamps you can hold your work vertically while cutting the slots along an edge. The trick is to mark everything so you can assemble your project in the correct orientation, I use different colored sharpies to mark each face inicluding which surface is the outside surface. If you're simple minded like I am, it's easy to reverse the surfaces and then you're stuck wondering why that box has edges that don't quite line up and...this is really horrible...it's not even square!

Dados give much more surface area than a **** joint and when dealing with MDF can be used to minimze the exposed hard-to-treat "edge-grain" that anyone that's tried painting MDF cabinets knows about.

The best method for appearance, if we're talking about MDF, is to use miter joints on all exposed outside panels. John Nail's stunning "Purple Puppies" were contructed with all miter joints and they turned out beautifully.
Perhaps John can join in on this thread and give us his advice.

Best Regards,
TerryO

[Ryan_M]

Yeah I already have a biscuit joiner. That's a decent idea about using the router table, just have to make sure bit size matches MDF thickness, but IIRC MDF is pretty close to a true 3/4".

[arlis_1957@yahoo.com]

be aware that biscuits swell with moisture so, put them in the micrwave for a bit before using. keep them sealed well otherwise. the can swell after installing. that is what their supposed to do afterall. but sometimes they can reveal their presence after a bit, so assemble on sunday and get to sanding the next weekend. i had this happen with an oak coffee table.

[Ryan_M]

Terryo, your method sound a lot like mine. FWIW For the biscuit cuts in the board that will show its endgrain I usually use a piece of paper under the jointer base so when assembled that edge will sit a few thou proud and can be quckly sanded flush. Sorta the same thing as what a flush trim bit does.

Arlis, thanks for the tip. I've used biscuits quite a bit and never had that happen to me... just lucky I guess. My progress it usually really slow anyway so materials have a lot of time to stabilize themselves without having to make an effort of it, but it helps to know which ones I need to be mindful of.

[terryo]

Terryo, your method sound a lot like mine. FWIW For the biscuit cuts in the board that will show its endgrain I usually use a piece of paper under the jointer base so when assembled that edge will sit a few thou proud and can be quckly sanded flush. Sorta the same thing as what a flush trim bit does.

Arlis, thanks for the tip. I've used biscuits quite a bit and never had that happen to me... just lucky I guess. My progress it usually really slow anyway so materials have a lot of time to stabilize themselves without having to make an effort of it, but it helps to know which ones I need to be mindful of.

Ryan,
I also use a piece under the jointer to allow for sanding the edge perfectly flat. After having had to use Bondo to get the edges to look good, I figured there must be a better way, although it took me a while to figure it out.

Best Regards,
TerryO