advice on clefting

[Brett]

after looking at cleft gates in another thread I'm keen to give it a go but not sure where to start.

 

I amuse it goes along the lines of - take one stem, welly in wedges.

 

But it cant be that simple?

[armybloke]

I don't do this sort of thing (only wish I could) but I attended a wood working workshop at Westonbirt Arboretum one sunny afternoon and it was excellent. You could look at local nature reserves etc or Wildlife Trust websites for events as they often do run similar workshops. We have a hurdle making workshop coming up soon - Gate hurdle making;

Construct a cleft ash hurdle with Ian Swain, learning to cleave timber, shape with a drawknife and make mortice and tenon joints. At the end of the day you should take home your own hurdle. Please note that you will need room in your car of about 1 by 1 metre, or a good roof rack. Some previous woodworking experience recommended.

Cost £70, plus £10 on the day for materials. Saturday 14th May 10am-5pm. Swanwick Lakes.

[Brett]

cheers mate, but that's a 700 mile round trip for me.

[Cracker]

after looking at cleft gates in another thread I'm keen to give it a go but not sure where to start.

 

I amuse it goes along the lines of - take one stem, welly in wedges.

 

But it cant be that simple?

 

Making cleft gates is 50% of my living these days,and yes, it's simple.

You don't need to go on a course.

 

Start your split at the pith. Spilt into quaters with wedges, or froe. Shape your uprights with an axe, final shaping with draw knife. Snap a chalk line along the length of the upright, or use a pencil and straight edge. This will be the center line for your mortises. Mark out mortise positions then drill them. I use a 3/4 inch auger for small gates. Drill three holes along your chalk line next to each other and clean out the waste with a chisel.

 

Next, cleave your rails in the same way you did the uprights, just thinner. Cut them to the right length. Put them in a vice, get a sprit level and mark a plumb line at either end. Make a tenon template from a bit of scrap wood and place it over your plumb line so that it runs straight top to bottom, then draw inside with a pencil so the tenon shape is on the end grain. Shape the tenon with a drawknife.

Now fit all the rails into the uprights and either drill and peg or use rose head nails, which look really nice!

If you want anymore info pm me. I make shave horses, froes and green wood working tools. My froes are hand forged £35 deliverd.

[Brett]

cheers mate, excellent, I've got a 8' long plank of burred elm I milled out a couple of years ago, I've been wanting to make it into a table, when I seen your gates I decided that how I want to do the legs etc.. Defo interested in the tools, maybe some pictures - the names mean nothing to me yet

[Cracker]

This is a drawknife....

 

 

...and here's a froe

[Ross Macneil]

You will also need a cleving break.

[agg221]

I am no expert, but a few subtleties of cleaving I've learned along the way:

 

Some woods cleave, others don't. Oak, hazel, chestnut and ash all cleave well, elm doesn't.

When it's very fresh it splits very quickly, which means you can't control the direction of the split. When it's very dry it tears out, which makes splitting radially more controllable, but splitting across the width (i.e. round the rings of the tree) almost impossible. The ideal seems to be down for a few months.

First stage of cleaving is easiest as you say with some wedges. This takes it down to quarters or thereabouts - depending on how big it is. Wedges run the split pretty much as it comes, the froe gives some directional control but only when the section is thin enough to get a bit of bend, at which time you need a cleaving brake.

It took me a long time to find details for a cleaving brake - they're one of those things which is really simple but a lot of little non-obvious details make them much more comfortable to use. Some hold the workpiece upright, others horizontally. I prefer the latter as it means the length of wood is unlimited and gravity works with you, which is good for heavier sections. Mine is two posts banged in well, about 3ft apart, with a horizontal rail coach screwed on about stomach height on the front face. The rail coach screwed to the back face is on a slope - at one end its lower edge is slightly below (say an inch) the top edge of the front rail. It slopes up so that at the other end its lower edge is about 6in above the top edge of the front rail. You can then push your section in to the gap between the two, slide it so the length sticking out is right, and push it to the side until it jams. Because the front and back rails are separated, you can position it so that the end sticking towards you is higher by lifting it up and it will then slide in further.

When you're using a froe it has a tapered blade, like a wedge. You hammer it in with a wooden mallet (beetle) to get it started. Don't use a steel hammer as it peens out the back edge and it won't slide in the split. You can then control the direction the split goes - put the fat side downwards and push the handle downwards. If you use your other hand to bend the lower half of the split part down at the same time it does it faster. You have more control if you keep pushing the froe up as far as possible while the split advances. All this only applies while the split is advancing towards the front rail - once the split is over the front rail it runs straighter, but you have less control if it hits a weak spot, so it's best to pull out a couple of feet at a time to split, the rest being behind the brake.

The basic cleaving action creates wedge shaped pieces, thick end from the outside of the tree, pointy bit from the middle of the tree. This means they're not parallel sided. Try and cleave it parallel sided and it will just twist to run wedge shaped again! If you need parallel sided, this is most easily done by cleaning up with an axe or drawshave. A drawshave can be used in the cleaving brake, by moving the part so it drops lower and moving it back between your legs to sort of sit on it to keep it sprung and stop it moving. If you do this, be aware that the more you spring it down, the more the drawshave can whip down the length, effectively cleaving, if it digs in a bit, so it's a balance. You can drawshave the ends in a cleaving brake, but you need a loop of rope to put round the workpiece, a bit back from the end, then put your foot through it and push down.

 

Hope this helps - I've been making a lot of chestnut ceiling lath and tile batten for my extension - I now understand why ceiling lath retails at 49p per running foot!

 

Alec

[slack ma girdle]

The BTCV woodlands book has a good section on green woodworking, or consult the bible (Green woodworking by Mike Abbot, the grumpy man of the woods).

[Cracker]

A quick cleaving break to get you started, a log with two flat side opposite each other, lay it on one flat side then cut out some rectangles of various widths. You stand on the log and hold the timber you're cleaving so it fits tight in one of the slots, give you a bit of cleaving leverage.

 

To be honest I rarely use a cleaving break when making oak gates. I find the best way to get them to split how you want is to start the split at both ends.

Chestnut seem to respond much better to the brake. It makes life much easier if you start with nice straight grained, knot free timber.

 

A good way to practice "steering" your cleaving is with hazel rods. I split hundreds of feet last year for a wattle and daub build.