dealing with Knots - woodworking

[Mark Grant]

I was in Austria the other week and I saw several wood gutters, all softwood.
I'd go with the bitumen, a nice thinned coat first followed by a full coat.

 

[Accy cyclist]

I'm listening to the Notts County v Accy Stanley match on the radio and Stanley have just equalised in injury time!

 

[Zimbob]

I was in Austria the other week and I saw several wood gutters, all softwood.
I'd go with the bitumen, a nice thinned coat first followed by a full coat.

Aye, Redwood used to be used a good bit for guttering in the U.K too, at least down Manchester way, always seemed to be a bit counter-intuitive to me, but it worked...

Often painted I believe, and painted Redwood, if maintained, can last for many, many years

Looking at the picture, i think this is most likely Whitewood, as opposed to Redwood, but the principle of treating/sealing it will be the same

 

[slowmotion]

You could always put a low profile plastic gutter inside, cunningly concealed by your rustic timber....

 

[slowmotion]

@woodenspoons is right with the plug idea. Even if you paint it with bitumen, it won't stop the knot going AWOL over time. Bitumen isn't an adhesive. I would drill out the knot with a holesaw, make a timber plug with the same hole saw, and fix the plug in place using a low modulus silicone mastic. As others have said, that timber is going to move all over the place.

 

[MikeG]

[QUOTE 4932006, member: 9609"]out of curiosity what would be the best choice of wood to use here and how would you finish it ?

I'm not going to change from what I am using, its made now and when painted it will be in use, I reckon I will get longer than two years before needing replaced. I'm just curious what would be the best choice, I'm thinking Oak ?[/QUOTE]

In terms of durability, jarrah or teak would be your best bet (good luck working them, though. They're hard as nails, particularly jarrah). However, I am pretty sure they are both on the CITES list, as endangered, so probably not the best material for a gutter.

Here is a useful image, albeit the segments aren't sequential. Of the commonly available European hardwoods, oak and sweet chestnut would be my favourite for the job, but larch would survive longer.

 

[sheddy]

Best for guttering - bamboo ?

 

[Randomnerd]

Larch - but made thick enough so they don't warp, and with no sapwood. I made a few years ago using a gutter adze - - tooled finish resists rot better than sawn -

 

[sight-pin]

Another option, You could always glass fibre a run of light matting inside.

 

[Mark Grant]

[QUOTE 4932009, member: 9609"]I have been told you shouldn't thin bitumen, but like you I would thingk a bit of thinners (10%) would help in soak in for the first coat.[/QUOTE]

Years ago bitumen was often mixed with creosote to coat wood cladding on barns and suchlike, the last time I did this was in the late '80s / early '90s on a garage in Walton on Thames.