Biscuit help

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I bought a harbor freight biscuit joiner and used it for the first time this weekend. I read good reviews and it’s 1/4 the price of all the rest so I gave it a shot.

I made a table top for a small package table that will sit outside. I got inspired by ianwater’s curved leg picnic table. This one will also feature curved legs.

Anyway, I was in a rush and working on several projects at once. I used the biscuit joiner – first time I ever used one – and I noticed after gluing it up that a couple of boards sat proud. Not a big deal for this project. I can sand them down. But one reason I bought the joiner was to do a dining table. This was sort of a practice project.

2 part question: what kind of spacing and depth below the surface should the biscuits be, and any tips on how to handle the machine for best results? With such a small fence, it’s easy to wobble around after a few cups of coffee. Should I make a large fence or will am improved fence be negligible?

Losing fingers since 1969

Kind of hard to tell somebody how to do something without showing them but I’ll try to add whatever hints I can.
I don’t think adding any fence should be necessary.
I hold mine down flat right on the plate. (see pic)

(some people may not be comfortable holding it like that, but I find it works that way the best for me.) Then make sure you push it in nice and straight without lifting it up or down.
Having your wood clamped down solid will also help.
Just practice, practice, practice

It’s not unusual to see football shaped divits on a table top when they aren’t used correctly. If you put them to close to the surface, the biscuits will swell from the glue, making a raised area. Then, if you sand it smooth before the swelling subsides, it leave a depression shaped like the biscuit. I’m not poo-pooing biscuits, but put them at or below 1/2 way down the thickness, and then let them dry thoroughly before working your table top down.

"I long for the day when coke was a cola and a joint was a bad place to be" Merle Haggartd

I agree with Fred, also there can sometimes be vertical play between the biscuit and the slot which has been cut so when you do glue try and use a clamping caul across the top surface which will hopefully keep the surface flat and keep you from having to do a tremendous amount of sanding.

Ditto what has been said above. I’ve read somewhere that leaving glue off the biscuit and just putting it on the edges of the boards avoids hassles while allowing the biscuit to keep the joint lined up.

Great advice all. The palm trick sounds great.

Losing fingers since 1969


I’ve got a tiny (girl-sized) biscuit joiner and I also hold it down with my hand. Another thing that can cause a problem: if the joiner isn’t powered up fully before plunging, it will sometimes lift or move. (I sometimes have a problem with impatience. ) Keep practicing!


“Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety.” Benjamin Franklin

I used my biscuit joiner few times on cutting boards and today as a mater of fact.
I was joining to 2 pieces of 2×6 for the bench seats and I wanted to reinforce the edge glue.
I did like Bently showed.
When the pieces are smaller I usually but the against a fence.

I do put the 2 pieces against each other as I would glue them and mark both at the same time. There is always a little play for me. I was told to slightly wet the biscuit so the swell lightly and that should take care of that. I have not tried it.

Abbas, Castro Valley, CA

Practice practice. I guess I’ll practice some more. I want to build a new bench as part of my new shop layout if I ever get around to that. LOL. If I can make that flat I can make my dining table flat.

Losing fingers since 1969

By the way, many of the reviews for the harbor freight joiner said it has excellent dust collection which it really does. I had the vacuum connected to it and there was not a speck of dust anywhere.

Losing fingers since 1969

One other thing, My Biscuit Joiner has a base that is just a little thicker than 3/4" so I have to make sure that my wood is hanging over the edge of the table when I’m doing it.