How to make and fit window boards?

Edz · Post by **Edz** » Wed Sep 19, 2007 9:53 am

Hi. I need to fit some window boards having removed all of the old ones and plaster boarded and skimmed the reveals.

2 questions. Firstly, how best to stick them so that I dont see screw heads if I decide to stain them? I did hear one guy on this site used expanding foam and plonked some heavy weights on the board while it set off but I don't know if that is best practice?

Secondly, most window boards I have seen appear to extend beyond the window opening by 4 inches or so at each end. Should I therefore cut my my boards 8" longer than I need and then notch out?

Grateful for any advice. Thanks

leebwk · Post by **leebwk** » Wed Sep 19, 2007 10:09 am

Hi Edz,

Most window boards are fitted before plastering as the plaster helps to hold them in place aswell as mechanical fixing, i have seen expanding foam used to fix window boards but i would,nt recommend it, i would definately screw them down and fill the countersunks with a good quality matching filler.
Yes you will have to cut your boards longer and notch them out for the extension length is down to personnal preferrance

big-all · Post by **big-all** » Wed Sep 19, 2007 10:14 am

assuming you are using solid wood

your boards should be glued together in sections alternating cup up cup down[wood grain]
so if your boards need to be say 11" inches deep you can make from 3+4" boards with only the last board needs to be full width
note that 4"planed boards will finnish up at around 11"[3x94mm]

assuming you have a surface to work to no nails or silicone would be my choice

Edz · Post by **Edz** » Wed Sep 19, 2007 11:44 am

Thanks for that.

I had however assumed that I would just by boards that would at least be the right width or over and cut them down to size rather than joing bits together. Is this practical?

big-all · Post by **big-all** » Wed Sep 19, 2007 12:11 pm

you can buy window boards one size but you risk cupping

you can also buy plastic window boards in white

Edz · Post by **Edz** » Wed Sep 19, 2007 12:53 pm

Is cupping where they warp and curl up?

I take that best practice is to take a plank, slice it into 3 or 4 lengths, then reverse the direction alternately and glue back together. Have I got it right?

If that is the case, do I need to dowel them too as well as using glue?

Also what glue would you recommend? Cheers

skiking · Post by **skiking** » Wed Sep 19, 2007 12:54 pm

cupping ? - please explain

Edz · Post by **Edz** » Wed Sep 19, 2007 12:57 pm

Glad it's not just me. Though I am just a DIY'er.

big-all · Post by **big-all** » Wed Sep 19, 2007 1:09 pm

cupping --middle raised compaired to edges --"curling" yes good explination
twisting --propeller shaped
bow ------bent like a cross bow or bannana
shakes---been struck by lightning or felled badly causing splits /diconnected fibres that are only often apparent when wood is worked

dewaltdisney · Post by **dewaltdisney** » Wed Sep 19, 2007 1:10 pm

Ski,

Cupping is the tendency for the wood to curl in the direction of the annular rings. As Big All has said alternating the rings of each board when jointing helps to level out the tensions. Another thing that you can do is run a shallow saw cut along the backs as this releases a lot of the tension that can build due to hygroscopic movements.

I thought that waterproof MDF was the stuff they use these days. This would be easy to cut and shape but tedious to paint. I have stuck a board down with Seriously Strong Stuff and that has not budged.

DWD

Edz · Post by **Edz** » Wed Sep 19, 2007 1:40 pm

Hey, great info. That's sorted out the definitions.

What about the joining? Dowel and glue? And, which glue. I'm dead keen not to get it wrong as I have 14 windows to do and would like to use hardwood and wax it.

big-all · Post by **big-all** » Wed Sep 19, 2007 2:37 pm

yep dowel and glue one every 9 or so inches
10 min wood glue then you can free up the clamps after 2hrs in a cold workshop or an hour in the warm
will still be a bit delicate for an hour or 2 but will allow you to use the clamps again
http://www.toolstation.com/index.html?code=82652

skiking · Post by **skiking** » Wed Sep 19, 2007 2:47 pm

It amazes me that an inch or so thick piece of wood is going to curl up like that

I've got one to replace in the coming months. Glad to have got this info - hope I remember it !

Edz · Post by **Edz** » Wed Sep 19, 2007 3:56 pm

Hey, thanks for that. I just cut a softwood plank to size to make a window board in my last house on a kitchen extension .. it warped to buggery.

Next question, if you were to use hard wood, what type would you go for?

I have some 20mm oak flooring left so I thought I might use that but I know that oak moves a fair bit. What do you reckon??

Jaeger_S2k · Post by **Jaeger_S2k** » Wed Sep 19, 2007 4:14 pm

skiking wrote:It amazes me that an inch or so thick piece of wood is going to curl up like that

I've got one to replace in the coming months. Glad to have got this info - hope I remember it !

The thing to remember is that fine piece of wood is that shape because that's the shape we cut it to.

If the wood decides it wants to be a different shape it will still be a fine piece of wood just not the shape we want.

If you think of it more that the wood hasn't warped it just more comfortable lying in a different position?