I have found that when boards biscuit connected on edge are not quite perfect that it is the fault of the boards and not the saw or biscuits. Sometimes, the boards will be warped very slightly and sometimes they are different thicknesses.

The solution, assuming the board assemblies are not too wide and the glue is fully dry, is to run the panels though a thickness planer until they all irregularity free. Then, sand the results for an even smoother finish.

Howard Ferstler

This string has gotten a lot of attention so my experiences may get lost in the crowd, but I just completed fabricating a frame using biscuits and it went together just fine. The caviat is, as I did my cutting I rigged up a fixture on my bench to hold the short 2 wide X 4 inch long styles so I could cut into the end grain. Prior to that I had assembled the entire piece dry and laid in indexing lines so I cut all the pieces true. I backed up my rails with a thin piece of long plywood nailed to the bench and a piece of sand paper glued to he edge so the workpiece wouldn't slip aside as the blade torqued into the piece. I guess, in my case, jigging up your work piece so it won't move is the critical part of using biscuits.

I think it comes down to personal preference when using biscuits. I don’t recall ever having issues with them and used them often. I can see if someone had trouble with them that it could be easy to say this is junk and not the way to do it. I used them in most glue ups. As for the bump issue, never had it. I did store my biscuits in an empty lacquer container (1 gallon) with a sealed top. It worked fine. I also had air conditioning in my shop so moisture was not a problem. When I start building furniture again, I will own a biscuit joiner again. Red

I think that Howard and Boondocker have both contributed valuable information. Thank you.

George

Did him say "jigging?"

yeah, wait a while & I'll set one up on my bench and show you what I mean .. .. .. .

.. .. .. ..or, maybe I should have said "fixture"?

I mostly just use the biscuits for joining table tops. Like others here have said, the biscuits haven't ensured alignment. I still have to be very careful with the clamps and culls to keep the boards aligned.
And I've read that the glue and biscuit can cause a swell at the joint that has to be planed or sanded (I haven't had that yet). But my biscuits tend to be a bit sloppy in the groove.

My scientific guess is that it adds some shear strength to the joint. If anyone thinks this is incorrect, I'd be interested to hear why. Might save me some time on my next table top.

Good topic. Thanks.
Dave

I have a Ryobi that I spent $100 on. I am a novice wood worker and have only used the machine on a few projects but I was amazed at the speed that I could cut the biscuit holes and get things aligned and glued up. I thought about buying a slot cutter bit for the router to save money but I can’t imagine that it would be any where near as fast as a biscuit joiner. I have never had "humps" or alignment issues. I lay the pieces to be joined on a flat surface and make a simple pencil mark where I want the biscuit. Making sure to cut marrying slots at the same time to ensure the heights are identical. Also I try to cut the slots at close to the middle as possible if not slightly below middle. I made a folding screen for my father in-law’s 50th birthday. Each section of the screen was 6 foot tall by about 20 inches wide. There were 8 biscuits in each screen section. It would have been a nightmare to try and align all those pieces perfectly at the same time for glue up. Using the biscuits to help me align all the pieces I was able to glue all 3 sections in roughly 40 minutes. In this particular project the biscuits helped me hold everything together in the right places acting as a third hand so to speak.

I also used them on a small table top for my daughter with no troubles.

David

David, you live very close to one of my favorite hardwood and exotic lumber suppliers. Wall Lumber at Mayodan. Do you ever go there? I went by there on one of my trips to a high school reunion in the late 90's. A very interesting place and nice people.

George

I've been on their website but not to the store. I'll check it out sometime.

I haven't purchased anything from this store yet but I browse the prices at http://www.hardwoodstore.com/specialty.html a lot. The price at The Hardwood Store are much cheaper than Wall Lumber. 5.73 for Padauk vs 8.00 at Wall Lumber. I think I should call the harwood store and make sure the prices on their website are correct.

Just called and 5.73 is accurate. Sorry to be off topic.. So, how 'bout them biscuit joiners???