Larch Preperation?

400R

Hi all,

I've made 2 new sets of entrance gates for my house and am using just steel frames with wooden inlay. The wood i've gotten is larch (5"X1 1/4" T&G). The boards are in 5' lengths and have been pressure treated. Whats the best process to follow now to leave a nice dark finish and also to make sure they're well treated? I'm totally new to wood preperation so step by step would be very helpful e.g sand/stain/sand/stain etc.

Thanks in advance.

Carlow52

You are on the right track for sanding/stain/ etc: there is plenty stuff online if u google: use a stain and not paint.
some observations:

are the steel frames galvanized?

was the timber treated after it was prepared?

How are u fixing the boards to the frames: stainless or brass or zinc plated fixings?

have u made provision for expansion contraction in the timbers, depending on moisture content at time of fitting into frame?

finally u dont want to be breathing the saw dust off treated timber:eek:

400R

Thanks for the reply,

are the steel frames galvanized?
The steel frames are galvanised but will be getting sprayed black first.


was the timber treated after it was prepared?
The only treatment the timber has had is standard pressure treating from the lumber yard.


How are u fixing the boards to the frames: stainless or brass or zinc plated fixings?
The steel frames have a flat bar around the edge on the back face. I planned to drill and countersink this and screw from behind leaving the front looking clean.


have u made provision for expansion contraction in the timbers, depending on moisture content at time of fitting into frame?
The timber has been laid out flat on spacers in an open faced shed for about a month now so i thought this would dry it out completely? I didn't think they're would be much expansion/contraction once stained after that? Having said that i will be leaving a 3mm/4mm gap all around and running a bead of sealer. Is 3 or 4mm enough?


finally u dont want to be breathing the saw dust off treated timber
Cheers for the heads up!

Carlow52

nice answers:)

If u cut the board to length u need to treat the ends

I would use stainless cup head bolts.
Drilling the top and bottom flat iron , say 2 screws per board will be hard unless u have a decent drill press and good bits:)

Given that it is galvo'ed I would be reluctant to drill/c/sink so here is what I would do
get a 50mm by 2 or 3mm length of flat Alu and a 20mm wide length of flat Alu the same thickness as the flat on gates.

drill the alu at the correct centres for the boards along the center line of the 50mm wide alu
The idea is that the bolts or c/s screws will pass through the 50mm alu and rest on top of the flat iron

The 20mm alu will then fit between the inside face of the 50mm alu and the timber and give the 50mm a flat grip on the boards and the iron.
after u paint the alu black run a bead of clear silicone along the 20mm alu to seal it off.

Re the gap: say 5mm both sides and leave 5 on the bottom with nothing on top.
Dont seal bottom gap as it will allow water to run off

ps: 13/10/2010: the 50mm is just an indication of what u might use, the idea is to clamp the timber against the flat iron.
You could counter sink the alu and use screws if you wish: I just prefer the pull you get with the bolts:)

The other advantage of this system is that the screws are further in from the edge so less risk of splitting

400R

I've read this a couple of times now but i just don't follow? Sorry!

The first point i'd make is-i do have a drill press and i have lots of cobalt bolts (i'm a fitter by trade)

Are you saying that by countersinking the flat on the gate i'm leaving myself open to 'rusty runs' later on? Agreed,its always going to be a possibility.

Re: the alu flat idea...just to point out the top of the gates are curved so getting alu shaped to suit might be an issue?
Do you mean by using the alu strip i'm not having any contact between the screws and the steel? Sorry-i'm just being thick-but i just can't picture it?

Just on the sanding of the boards-what grit of sandpaper would i start with? Probably finishing up with something like 400/600? (maybe too light? I'm just used to sanding cars! :rolleyes:)

Thanks for the help!

Carlow52

Badly written on my part:)

dont have the cad on this computer:)

I was just trying to avoid drilling the galvo because of the rust issue and if u didnt have a drill press. no issue with screw/bolt contactcontact .

i suppose a bit of hammerite or equiv on the counter sink when u do the final fix would do the trick.
I would use SS screws or bolts and not ZP or similar crap

The alu is like a big continuous washer or flange supported on the flat iron on one side

Sanding not my forte: see diydata do co dot uk

keep well

400R

Thanks for you're help Carlow! I'll post some pics when done.