Leg tapering jig (for use with jointer)

[craigmarshall]

For this jig I use a small square (must be cut accurately) piece of 18mm MDF. I used a small festool clamp with a tiny head for this. You must make a hole that the clamp head can fit into (If necessary, jigsaw/bandsaw a rectangular section out):



Make sure the top end of your table leg is square to the edge of the jig, this is important. It helps to have the taper marked out on the leg (both end points and the line in between) and on both sides of the leg, just to make sure you can't go wrong.



You'll need either calculate the height using a bit of 'rithmatic, or use trial and error and gradually get the line on the leg parallel to the planer table as the material is removed. The first leg you do is a little bit fiddly, but subsequent ones take literally seconds to complete!



And soon, you'll have a correctly (and squarely) tapered leg. Rotate the piece around and do the other inner face. You may find that a wider jig helps stablise everything. Another option is a second hole for another small clamp, but I didn't find this necessary.



Please ask if you have any questions.

Cheers,
Craig

[dom]

Simple and efficient, bit like me actually ;D
Nice one craig

[sainty]

Doesn't it take a bit of a nose dive into the cutter on the first pass?

Not having a dig just wondering as you seem to have used it successfully.

Rgds


Sainty

[mrgrimsdale]

Wouldn't it be quicker and easier to: 1. Mark it all up - which you've got to anyway. 2. Saw of waste with bandsaw or whatever. 3 Plane to marks, over the top of planer, or by hand.
I'd probably finish it down to the line by hand - something tells me that this would be more accurate than relying on a jig.

cheers
Jacob

[craigmarshall]

sainty said:

Doesn't it take a bit of a nose dive into the cutter on the first pass?

Not having a dig just wondering as you seem to have used it successfully.

Yes - you're quite right, it does munch a lot off on the first pass but as long as you don't apply too much downwards pressure it seems quite safe. Also - you're cutting so far onto the waste side of the line that even if it chipped out, it wouldn't make any difference to the finished product.

I suppose if you're only doing a very slightly tapered piece, you might be better off doing it another way?

Cheers,
Craig

[craigmarshall]

mrgrimsdale said:

Wouldn't it be quicker and easier to: 1. Mark it all up - which you've got to anyway. 2. Saw of waste with bandsaw or whatever. 3 Plane to marks, over the top of planer, or by hand.
I'd probably finish it down to the line by hand - something tells me that this would be more accurate than relying on a jig.

I'm not really sure, this is just the first method that came to mind and it was so easy and I had such an accurate and repeatable result that I had to share it with you. I also don't see it as relying on a jig as much as choosing to "exploit" a jig, to get a perfect result in less time. I certainly couldn't do it any faster or better manually, obviously the more skilled might.

Anyway - there are at least two tapering options now! The easiest method of all is to incorporate non-tapered legs into your design, but only by fifteen minutes.

Cheers,
Craig

[nickw]

So you need the guard out of the way, and are poking a long, springy stick, with minimal support into the rotating block. I wouldn't feel happy doing that, and I reckon Scrit'd have a fit. Stick to the bandsaw method or get hold of/make one of the standard tablesaw jigs.

[craigmarshall]

Okay.

I didn't think it was that unsafe a method, but I am sorry if I've upset anyone and I'm happy to remove the post if necessary.

For the record, I am personally quite happy doing this. 45x45x875mm of sapele really isn't very springy, and there was no "poking" involved, just a heavy first cut.

But - I don't really have the energy or experience to defend my position, so I'll stop now.

Craig

[dom]

I tried it today and if you only remove a little at the time it works fine. Yes there should be a guard in place, but don't worry Craig no one is upset, we all do things differently and express ourselves differently.
The safety aspect though is important especially to someone just starting out.

[engineerone]

whilst jacob may well be right about doing it by hand,

my recent experience is that you need to practice a lot to get it right, this method of craigs has some advantages and could be improved to include a guard and make it easier to use without taking great lumps off too.. a planer is not really designed to do anything other than produce flat and square surfaces, but then in principal a table saw is not designed to cut other than square to the plane, unless with a mitre gauge so you can use a taper jig, which could also be quite dangerous if not used properly.

keep the ideas coming craig, as long as you are using them with care, they can be safe.

paul

[mrgrimsdale]

You could have a guard in place anyway. Wossa prob? It's only like planing a thicker piece of wood.
Craig don't worry about upsetting anyone we are all thick skinned and insensitive ;D ;D all the prima donnas are over _there

cheers
Jacob

[craigmarshall]

Okay - thanks for the support chaps.

I'll see what other questionable ideas I can dream up ;D

Craig

[Alf]

engineerone said:

whilst jacob may well be right about doing it by hand, my recent experience is that you need to practice a lot to get it right

I don't think doing tapered legs by hand is difficult per se, as long as you already have the necessary skill set. If you don't, well it's more of a learning curve (learning taper?!) but that's 'cos learning to plane to a line, square and straight, benefits from practice. Putting another way, it worked okay first time when I did some, and if anyone can screw up then I can - often getting the same thing wrong time after time... ;D

Sorry, wandering OT. Erm, relevant comment.. Not honestly how I'd have done it, but if it works and you feel safe, why not?

Cheers, Alf

[nickw]

None of the bridge guards that I know of would go high enough to allow the tail end of the assembly (stick, clamp and block) to pass under them, and even if they could they'd then be of little use as a guard. This means either the guard is removed or you have to pull the stick back out after making the cut.

I hope I don't need to explain why the first option is a bad idea.

The second is not brilliant because it is possible to drop the piece while trying to lift it back out. This will send the contraption at high speed across the room, and if your reaction is to grab the piece, or you hadn't quite let go anyway, then your pinkies will get mangled in the blades. Speaking as one who, under slightly different circumstances, has done this I can say that it is not a pleasant experience. Shall I tell you about how the surgeon had to remove the remains of my nail in order to sew my finger back together?

What's so difficult about the bandsaw method? One pass through the bandsaw cutting close to the line, a couple of swipes with a hand plane and you're done.

[andy king]

The thing that springs to mind looking at thi is that once the taper begins to establish, you are planing against the grain, so prone to breakout and tears and splits.
If you have the bed length, it would be better with the jig on the out feed so that you are cutting with the grain.
Jacobs method is an easier option to remove the majority of the waste, but if you do do a final clean up, I would do similar and rotate the leg so that the cut is with the grain.

Andy

edit: That's asuming i'm looking at the diagrams the right way, and the jig is on the infeed?

[craigmarshall]

Oops - I should have said - The jig is shown on the outfeed having just made a pass.

I believe I'm using a felder AD741 planer/thicknesser (the only planer I've ever had the pleasure of using), and I wrongly assumed that all planers work like this one, from right to left. Obviously from the confusion I'm witnessing they don't!

So - this clears a few things up:

1) you actually could have the guard over the part of the work that matters (although I didn't)
2) the grain is being sliced in the right direction, not the wrong direction
3) I can see how one would think there was "poking" going on, where it's not - more of a dragging action. Not dissimilar to surfacing a badly bowed board.

Cheers,
Craig

[mrgrimsdale]

craigmarshall said:

snip
surfacing a badly bowed board.

Cheers,
Craig

Hmm how do you do that then? You show me your way and I'll show you mine ;D

cheers
Jacob

[craigmarshall]

mrgrimsdale said:

Hmm how do you do that then? You show me your way and I'll show you mine ;D

Let me guess bandsaw most off then a few swipes down to the line with a hand plane? :-)

Craig

[dom]

Bada boom ;D

[mrgrimsdale]

craigmarshall said:

mrgrimsdale said:

Hmm how do you do that then? You show me your way and I'll show you mine ;D

Let me guess bandsaw most off then a few swipes down to the line with a hand plane? :-)

Craig

No. It's just that I've got into the way of doing it convex side first, instead of the hollow side, which is more usual AFAIK.
Somewhere about the middle of a bent and twisted board is the "average" surface which is in line with the optimum flat surface you are aiming for.
So I'd pass it over the planer with convex side down - but with pressure at the centre, not at the ends. It then cuts from the centre outwards as you make more passes.
Imagine the board like a canoe which you are floating over the planer with your weight in the middle - each pass cuts a lower, but straight "water line".
The advantage of this is
first that you are starting off aligned near to the flat surface rather than nipping the corners on the concave side,
and second that if the board is not, in the end, thick enough for your purpose, the thin bit will be in the middle instead of at the ends.
This means that for e.g. a sash pulley stile, it's useable - with the unplaned bit in the middle at the back but full thickness at the ends where the joining goes on.

cheers
Jacob

[craigmarshall]

mrgrimsdale said:

No. It's just that I've got into the way of doing it convex side first, instead of the hollow side, which is more usual AFAIK.

This is now way off-topic, but - I completely understand your explanation of your method, I just do it the other way, probably only because that's the way I've been taught to. I'd be interested if that really is the more usual method. (everyone else?)

I put it cup side down, so that the ends are touching, not the middle. Then I plane until it planes all the way through (you can tell by the sound - although you already know this). If one end has more of a "kick" than the other, I'll give that end an extra pass. Lather, rinse, repeat.

This proves more than anything that there's more than one way to skin a cat!

If I remember to, I'll actually give your way a go, because it sounds no harder, and might actually make more sense - the joints do usually come at the ends, which is where you really care about the thickness accuracy...

Thanks Jacob,
Craig

[dom]

Both methods work, but I tend more to Craug's method, depends on the timber. generally it depends on the timber, slight wind, cup etc.

[ddashk]

it you like the finish of the planer but not the questionable safety you could use a box jig to hold the legs up at one end and put the whole lot through a panel planer.

[Scrit]

Jan 29, 2008 18:31:48 GMT nickw said:

So you need the guard out of the way, and are poking a long, springy stick, with minimal support into the rotating block. I wouldn't feel happy doing that, and I reckon Scrit'd have a fit.

All I'd do is point out that it's probably intrinisically safer to carry out the process by roughing out on the bandsaw then using a jig in the thicknesser. Or just do the roughing with a conventional taper jig on the table saw and a single pass on the jointer (my preferred method) which is an any case faster

May 14, 2008 12:13:17 GMT ddashk said:

it you like the finish of the planer but not the questionable safety you could use a box jig to hold the legs up at one end and put the whole lot through a panel planer.

AKA a thicknesser for those not in the know.......

Scrit