New hardwood window sashes

[RichD1]

Making up some sapele window sashes to replace the rotten ones in my bay window.

A couple of questions guys:-

1. The existing fixed sashes are sitting on the cill. Should I machine an undercut to the front edge to aid water shedding? I was thinking about a 6mm high and deep rebate but would this be any better than no rebate at all.

2. Is it worthwhile to apply wood preserver like Ronseals 5 star once all the frame sections have been made and before gluing together?

Richard

 

[KenGMac]

RichD1, good evening.

Back in the day, a dead sash "generally" overhang the Sill with a drip machined close to the underside front edge of the dead sash bottom rail, the drip does not have to be deep, it is there just to allow rain water to collect and [drip] from the underside of the dead sash.

As for priming and pre-painting prior to assembly, short answer is yes.

I have seen primer and undercoat applied, then allowed to dry [if possible] the work then assembled, a second coat of primer applied flooowed by the final coat

Ken.

 

[mrrusty]

You have probably bought the timber already, but in the future for painted joinery I suggest considering Accoya https://www.accoya.com/uk/products/windows-doors/ rather than using tropical hardwoods. It's not only sustainably plantation grown, but is ideal for external joinery as it barely shrinks/expands which aids paint life and has extremely good durability. It also machines easily. You will find that many (most?) of the higher end window and door manufacturers are using Accoya for some of their products. I've used it a fair bit and now wouldn't use anything else for external joinery. Disadvantage is it's not very pretty so not so good for just staining and you have to use PU or epoxy glues and stainless fittings.