lath

[canoehead]

anyone got any tips on riving or cleaving lath from chestnut? how do you keep it from running out? how much difference does the stock make? anyone?

[wisewood]

Not my area but don't you need to use a froe with a cleaving break to control the split, rotating the branch so that you can force the split back to centre before it runs off.

[Nellybelly]

anyone got any tips on riving or cleaving lath from chestnut? how do you keep it from running out? how much difference does the stock make? anyone?

 

The trick is to put the thicker cleft under tension when you start to run off line. Try and use the best wood that you have available although the old coppice worker would have used almost everything

[agg221]

I've done quite a lot for my own use (probably about 300sq.ft). As has been said, a froe, beetle and cleaving brake are essential. I also use a billhook to trim up the fat bits so the whole thing will lie with a flat face outwards to make plastering easier. 'Froe to the fat' is the thing to remember, i.e. push the handle towards the fat side when it's running out.

 

I've found it makes a big difference how freshly cut the timber is. Really fresh stuff cleaves very easily, which makes it run out more easily before you can stop it. Once it's dry it gets a lot harder (still possible) but there's a sweet spot in between where you can control it but it doesn't take too much force. You can get more extreme correction of run-outs by not just twisting the froe but also bearing down on the lower half of the section.

 

In theory you can cleave a piece into thirds or quarters directly, but I've found it a lot easier to try to divide into equal halves.

 

I can't get anything to cleave width-ways reliably, or into anything other than 'wedges' i.e. radially straight out from the tree. I tend to split the wedge down so it's getting a bit thin on the inner edge, then lay the piece on the ground and line the froe up along it where I want the inner edge of the real width to be, then put the front corner of the froe on the surface, about 8" up from the end and hit it with the beetle. This creates a progressive split up the piece as the froe goes in and the bottom edge tends to break out in line. Do the same again about 8" up from the end of where the split runs to and keep going to the end. This usually gets it fairly straight.

 

Don't try to make lath too long - 3' and 4' are the standard lengths, depending on the spacing of the battens/studs/rafters.

 

I try to make mine just under 3/8" thick and about 1.25" wide.

 

Hope some of this is useful.

 

Alec

[canoehead]

thanks, that's brilliant alec.

 

300ft2 is a lot.

 

will try that this w.e. had exactly the same issue, couldn't get anything other than a wedge out, then trying to split the wedge it was all going wrong. that's why i wondered if you had to use a riving knife?

 

i particularly liked the saying 'froe to the fat', i've obviously been froeing caution to the wind.

 

have you got any photos? esp of your finished product?

 

thanks

 

rick

[agg221]

Hi Rick, I'll take some photos tomorrow - it's all bundled up in the shed waiting to be installed. I made it as one of the few bits I could get on with last year during the interminable wait for the architect and listed buildings to get from planning permission (granted Dec '10) to actually being allowed to start construction (Oct '11). I wouldn't say they're perfect, but they'll work. I've been making batten by cleaving out wedges and then hewing both faces to turn the wedge into a rectangle, so some of my lath is cleft (or is it cleaved?) out of the ones that run out - hence up to 8ft lengths. I wouldn't do this for any other reason.

 

Alec

[agg221]

Finally managed to get the combination of phone and charger in the same place at the same time, and took a couple of photos. There is no way I can think of to make lath look either exciting or artistic, but here goes! The laths in the first picture are about 3' long, 1.25" wide. Because I'm making mine out of offcuts, they're random lengths. I make up a load, then sort them into gradations of a foot in length (2-3', 3-4', 4-5' etc). I haven't worked out all my stud spacings yet, otherwise I'd sort for that instead. I then bundle them in batches of 8 as this should cover a foot width. It means if I pick up a 4-5' bundle it will cover 4sq.ft. The second picture shows bundles of them stacked away in the shed roof.

 

Alec

[Crazy Cutter]

The brotch maker here would leave his wood six weeks before riving.

[canoehead]

thanks for the pics Alec. i think i'll try and persevere with splitting them, rather than sawing them. your's look good. it seems a good use of a material that would otherwise get burnt. and an efficient way of processing them. have you plastered to riven lath? i've only plastered on sawn, do you use much more plaster?

[agg221]

I haven't plastered over any yet so can't comment on consumption. I don't think it will be too bad - they're fairly flat and I reckon I won't need a total thickness above half an inch including snots to get the coverage. I don't mind if it's a bit 'wavy' as a surface - if I wanted flatness then I might as well use plasterboard!

 

One other thing, which I've never seen mentioned anywhere but I've found helps. Once I've got the laths into the right length and width, and cleft as thin as they're going, I true them up with a billhook. I try to do this mostly on what will become the back face, but I also deliberately leave the billhook dull, and run it down the grain, not across as you would with a side axe. This creates a combination of tearing and 'furring' on the surface, so if it has to be used as the front face, or bits of it do, the plaster will stick well.

 

Good luck!

 

Alec