Using a Biscuit Jointer

[brianhabby]

Hi all.

I need a bit of advice on using a biscuit jointer. I've used it a few times for holding trim along the edge of a manufactured board such as ply. I've always thought that one of the main benefits is the fact that the biscuits help you line up the work but I find that it often doesn't do this.

A job I was doing today has finished up with the board proud in a few places when it really should be flush.

Is it technique or the fact that I am using a rubbish tool?

Should I go back to using a slot cutter in the router? I don't recall having these problems when I was doing the job that way.

What do you think? What do all you experts use?

regards

Brian

 

[9fingers]

The accuracy depends on your BJ design. If the guide rails allow the motor unit to move in ay other plane than that of the blade, the slot position will vary.
Also most of the holding pressure should be to push down on the fence and a small amount to push the blade into the cut. Do not push down on the BJ body.

Bob

 

[brianhabby]

Thanks Bob,

Must check for play in the blade position, never thought of that. I am aware that you need to push down on the fence and this I was careful to do, having had the problem before.

regards

Brian

 

[9fingers]

Brian, talking of blade play, I recall someone here (or elsewhere maybe) having problems with end float on the shaft which carries the blade. Check for this as well as play in the guides.

Bear in mind that many BJs are modified angle grinders where there is no need to pay attention to end float.

Bob

 

[brianhabby]

Will check it out tomorrow Bob, thanks.

regards

Brian

 

[Digit]

My wife bought me a biscuit joiner for Christmas some years ago.
They weren't around when I started woodworking so this was a new departure for me.
It took about five minutes for me to decide to throw the fence away as the slightest error in alignment in one half of the job was in the opposite direction in the mating half, sort of forming a shallow letter 'X'.
Since then I have always worked off the base of the machine, knowing that it will be sitting in the same plane as the work piece.

Roy.

 

[Mr T]

Hi Brian

It may be worth checking the locking mechanism on the fence. I find, with my old Makita, that the fence can slip if the locking lever is not really tight.

Chris

 

[Smudger]

That was the only problem I ever had, loose fence. And mine was cheap as chips.

That and a piece of random metal getting through the blade slot. Never understood that one...

 

[ivan]

Provided the clamp doesn't slip, the fence on a cheap machine can be made to work by using // sided setting blocks (in practice you need less than half a dozen thicknesses, and not all at once): this ensures the fence is set at the correct height and also // to the base.

 

[George_N]

My biscuit joiner has a fairly good fence (Freud) but I still get the best results by working with the joiner and workpiece on a flat reference surface. I generally use my home made router table top as it is pretty flat. The router table has the added advantage of having a fairly tall fence (150 mm) that I can stand pieces on edge, square to the table, for slots near the edge, as for making cabinets. Setting blocks also work well as Ivan said, but I like to use the reference surface method. That works well for 18 mm thick sheet goods. For thinner or thicker material I use shims either under the sole of the biscuit joiner or under the workpiece. I keep some scraps of hardboard (3 mm) and MDF (6, 12 and 18 mm)which give me most of the combinations I need.

 

[OPJ]

I've also got a Makita jointer and, I must admit, I sometimes find it a bit hit-and-miss. When edge-jointing boards, as long as the mating edges are all square and the knives were set correctly in the thicknesser :roll: , I can get joins that only really need to have the glue scraped off; edges and faces seem to line up almost perfectly.

When adding a lipping though, just as you've mentioned, I also find that one side can be higher, the other lower, and that it doesn't always mate up perfectly. This is all using the fence, of course.

I recently on the Bosch we have at college (identical to Makita) that the fence sometimes locks slightly out of parallel to the base and/or cutter. The other thing to check could be the plunge depth - I found mine was too tight when I bought the tool as it set to cut at precisely half a biscuit's width!

My biggest problem with this jointer though is that I recently dropped it on a conrete floor and bent the fence! :roll: After some time fiddling with G-cramps and bits of scrap under the base, I almost got it back in to shape but then broke it trying to flex it in my own two hands! :shock:

 

[Benchwayze]

Can I suggest 'Making a Bookcase - Using Biscuit Joinery'. A DVD by Frank Klausz.

My first BJ was an Elu, one of the originals that used a movable body to make the cut. A bit 'hairy-scary' to use on narrow board edges, but great once you get used to it.

The latest models all seem to be the 'lay-flat' versions; much safer IMHO. Klausz uses one such and he explains it well.

The DVD is an entertaining 'watch' too.
Regards
John

 

[recipio]

interesting post.
I thought I had the same problems until I bought a Lamello top ten.
The differences in engineering quality are immediately apparent compared to my old Freud.
Everything is absolutely precise, the front fence always registers a parallel cut and the variable cutting height is a real bonus.
Some things like a bowed piece of wood, warped table on which to sit the BJ etc will determine the quality of the cut but the prime consideration is the build quality of the BJ which carries a cost.
Some machines such as a BJ and scroll saw rely on precision and as such are worth paying for.
I'm trying to expand the use of the bj and am making a finger jointer to cut 4mm finger joints . more anon.

cheers.

 

[ginsters]

i gave up on them ive had treud,trend and a cheap one (which was the best)
if i need to now i just use a router and use ply instead of bicuits and find it much more reliable

 

[Benchwayze]

I used a router, with a slotting cutter before I had a BJ. This was fine for small doors; where I would normally use a M&T.

However, you can join man-made boards with large biscuits and a router would be a bit hairy when you want to put slots on the face of a wide board, near the edges. Also it wouldn't be easy jointing plain mitres, a job for which biscuits are ideal.

After seeing Klauz's DVD, I made a biscuit-jointing board out of a 30" wide pice of Melamine, with a 2x2 fence at one end,. Clamp it to the bench and work off the fixed fence. Using the 2x2 to line up the pieces, I can push the jointer horizontally or vertically to make the cuts. If your bench is perfectly flat, you could just clamp the 2x2 across the end of your bench and work from a datum mark on the 2x2. If you want to cut slots across the middle of a wide board, another piece of 2x2, clamped across the workpiece, works in the same way.

(You might assume, correctly, that I am a fan of Klausz.; although I do know what to look for and when to ignore! :lol: )


John

 

[spudgun69]

I've got to agree with recipio, I used to have an Axminster BJ wich would give me the same results with the joints all over the place. Replaced that with a Lamello C3 and the difference is amazing, joints are perfect everytime using the fence. It's the old 'you get what you pay for'

Cheers

 

[Argee]

I've arrived at this thread a little bit late, having been away for a week. Some good advice already, Brian, including the fact that you do mainly get what you pay for, especially regarding the fence and motor bearings.

I did a page a while ago which may dot a few "i"s and cross a "t" or two. It's here if you get the time.

Ray.

 

[Benchwayze]

Hi Argee,

I do agree it's a case of YGWYPF!

Instance: although, my old Triton is well past it's 'desgin-by date', I still use it a lot. I am still "Humming and Hahhing" about getting a mitre chop-saw, wondering if I would gain anything for the outlay! (Although, a Triton is only as good as the saw/router you put in it!)

As for Biscuit Jointers, my best quality model is one of the 'dangerous-types' that has the swinging body. (Looks like an angle-grinder more than a biscuit jointer!) I used that a lot, but was never comfortable on narrow edges!

I recently acquired a 'Clarke' (Similar design to the Lamello) from a bereavement sale. It works ok, but I do think I might move up the quality scale, to a Lamello or maybe a Porter-Cable. .

John