Building an oak gate

[MattJ]

I'd like to build a garden gate from planks of green oak. Gate will be 3 foot wide, 6 foot high.

I was thinking of 3 planks 12" wide and 1" thick, with braces made from same planks, with 2.5" rose head nails on the front side, clenched on the braced side.

Anyone ever built a gate like that and have any tips?

I'm worried the clenched nails will look untidy, but if I use shorter nails, I'm worried the oak will pull the nails out as it dries, shrinks, and generally moves about.

Matt

 

[biffvernon]

12" is a very wide board. OK if air dried for a couple of years in a big stack but there is a risk that if you are using the wood from green there will be some cupping and perhaps splitting. I would be tempted to cut them to make twice as many 6" boards. Best to tongue and groove so you don't get a see-through crack when the wood dries but has somewhere to go when it gets wet. If square edged planks are butted together there is nowhere to accommodate the movement.

 

[GK]

You might want to pilot drill the nail holes first to prevent the grain from splitting out as it comes through the other side.

 

[skier-hughes]

I'm with Biff on the width of the boards.

How about turning every other board upside down so the grain is opposite? Any truth that helps at all?

 

[biffvernon]

Yes. Sort of. The idea is that the growth rings curve one way in one board and the other way in the next board so when they cup the alternate cupping direction evens out. Remember that maximum shrinkage is tangential to the growth rings. Shrinkage is less in the radial direction of the tree trunk and even less in the length.

 

[Penners]

How about turning every other board upside down so the grain is opposite? Any truth that helps at all?

The other problem with this is that mass-produced t&g boards often have the tongue and groove offset, rather than central to the thickness of the boards. So you could get steps in the structure.

Matt - I don't think clenched rosehead nails look untidy; just traditional.

Of course, you could use brass screws, but they certainly wouldn't look traditional.

 

[Penners]

12" is a very wide board.

Biff, do you know why mass-produced t&g oak floorboards often have multiple V-grooves cut in the back? I've seen it often and never known why they're there.

 

[biffvernon]

We have no idea. One has never seen anything 'mass produced'.

 

[GK]

I've seen oak flooring in mass production. Well, rural industry at least. A couple of flat depressions with chamfered edges moulded on the underneath, are for stress relief, apparently.

Over to you now.

 

[Penners]

We have no idea. One has never seen anything 'mass produced'.

Humble apologies, Your Majesty.

 

[Penners]

I've seen oak flooring in mass production. Well, rural industry at least. A couple of flat depressions with chamfered edges moulded on the underneath, are for stress relief, apparently.

Over to you now.

Thanks, GK. The ones I've seen are definitely V-grooves, but I imagine the principle is the same.

Stress relief is, of course, available in many forms.

 

[MattJ]

Thanks all for your input.

Tongue and groove sounds wise. I liked the idea of the wide boards but understand about the amount of movement, shrinkage and cracking to expect and how 6" boards might help.

The sawmill have quoted £5 for 6" boards, 6' long and an inch thick, so it looks like £40 will do my gate which is a bargain. I may buy some 12" boards anyway at that price and let them dry in the garage as I fancy some oak bookshelfs.

I think I'll have to practice the nail clenching. I've read of clenching irons, but it doesn't seem to be a stocked item at Wickes (nor anywhere else come to that).

Cheers
Matt

 

[middi]

If you buy wide green oak planks to air dry under cover somewhere, a very good idea and investment, make sure they are nice and flat and there is plenty air circulation around the individual boards. Also make sure they are weighted down for them to dry out reasonably straight.

If stacked incorrectly they will only be good for fire wood after a couple of years or so.

 

[Andrew Bodenham]

I'd certainly recommend that you practise your nail clenching technique. Having just completed a couple of plank doors in dried oak here's a few observations:

Prices for rosehead square shank nails vary enormously, so shop around.

Used outside you may well find that the reaction between the steel nails and the tannins in the oak leads to black streaks running down from the nail heads / tails. How about oak pegs, or bronze gripfast nails?

Pilot drilling is important if you don't want to split the wood.

Turning the tails over is easy, but you do need to be able to rest the head on a solid surface for support, or as I did have a helper "holding on" with a heavy hammer head / sash weight or similar

About 12 - 15mm overlength gives a good clench.

Once clenched the strength developed is phenomenal!

Agree with previous posters about plank width - 12" planks would almost certainly split as they dried out. Even 6" might split if used green. Air dried would probably be best.

For tongue & groove I routed a groove in both edges and fitted a 6mm oak loose tongue. This is easy and saves on board width compared to cutting a conventional tongue.

 

[biffvernon]

Yes, grooves and a loose tongue is much easier. If you can find one of those old wooden moulding planes that cuts a little groove next to a round bump you can give the edges a bead. It looks good and takes the eye off the crack. Of course you could do it with a router or spindle molder if you have the right cutter but that's much noisier.

If you buy some green boards and want to air dry them be sure to stack them flat separated by one inch square wooden sticks every couple of feet.