Sash window profiling and spindle moulders

[Walfy]

Good evening all

I’m tasked with making a curved top window. Difference is that it doesn’t need to open so have come up with the below profile where the glass is held in from outside with the 1cm thick chamfered piece (to get a good paint adherence for weatherproofing) client wants to go double glazed which at this size is pretty thick.

My question is how to create this profile (in brown, drawing is to scale) - I have a router table table saw etc but am considering a spindle moulder.

Can this be done in a few passes on a spindle moulder? If it were straight the table saw would be fine but not for the top curve. And I suppose ultimately would it be safe to do?

(Forget the roundover/ and chamfer I can do this on the table)

Very grateful for the collective wisdom as want to be able to quote the job.

Thanks all

 

[deema]

The whole thing can be done on a spindle moulder with a ring fence.

 

[HOJ]

My first observations are: why the double rebate for the bead/glass, are you matching existing, and 10mm for a bead is a bit fleet, the least I go down to is 13mm, and have you thought about how to make the bead.

I agree with @deema a spindle is an ideal machine for this sort of work along with a ring fence accessory, but if your buying one, along with the tooling, to just do this job its going to get pricy.

 

[Jacob]

Good evening all

I’m tasked with making a curved top window. Difference is that it doesn’t need to open so have come up with the below profile where the glass is held in from outside with the 1cm thick chamfered piece (to get a good paint adherence for weatherproofing) client wants to go double glazed which at this size is pretty thick.

My question is how to create this profile (in brown, drawing is to scale) - I have a router table table saw etc but am considering a spindle moulder.

Can this be done in a few passes on a spindle moulder? If it were straight the table saw would be fine but not for the top curve. And I suppose ultimately would it be safe to do?

(Forget the roundover/ and chamfer I can do this on the table)

Very grateful for the collective wisdom as want to be able to quote the job.

Thanks all




View attachment 196206

Why not take piece in blue whatever you'd call it, right across the full width and take out the step (brown). An unusual detail.
Or make the rebate deeper so you could put a normal sort of glazing bead in it, and again get rid of the step.
Modern stuff not my scene but I'd guess it's not an uncommon problem and it would be a good idea to look at others' solutions.
Basic rule is don't re-invent the wheel, look at how others do it first.
Spindle moulder - yes by all means but there's a learning curve.

 

[dzj]

If your arc is a segment of a circle, then a router and trammel will work.
A router and template(s) would work also.
A spindle moulder is best for the job, though.

 

[Jacob]

If your arc is a segment of a circle, then a router and trammel will work.
A router and template(s) would work also.

Or simplest with router and bearing.

 

[Ollie78]

Thats one pass in a spindle with a ringfence or bearing.
For curved heads I make a sled from mdf with locating blocks for the workpiece and big over centre clamps to hold it flat safely.
Make the sled a good bit longer on the ends than required this is to provide a safe lead in and out, and also wider so your hands are well away from the spinny bits.
I cut close to the curve on the bandsaw to make it a lighter cut.

You could do it on a router table but it will not be fun.
I am assuming it is a curved head not a bowed window which is a bit different and more tricky.

I am also curious as the the reason you have the extra big blue bead. I do not think external beading is a good plan if you can help it. If you use low sightline heritage units you wont need such a deep rebate. Look at hodgesons heritage putty for DGU`s.

 

[Walfy]

Thank you for the responses

The huge bead is really just so the 2.1x1m pane doesn’t fall out… I am considering two panes one rectangular and one with a curved top but having 5 panes make the glazing bars too thick

guess I should have mentioned that i will mortise and tenon the glazing bars - on the inside - the outside bars will be stuck on and I was planning the pictured for the exterior as I felt it was more in keeping with the original.

 

[Jacob]

Thank you for the responses

The huge bead is really just so the 2.1x1m pane doesn’t fall out… I am considering two panes one rectangular and one with a curved top but having 5 panes make the glazing bars too thick

guess I should have mentioned that i will mortise and tenon the glazing bars - on the inside - the outside bars will be stuck on and I was planning the pictured for the exterior as I felt it was more in keeping with the original.

Looks a very nice classy old window - I would have repaired or replicated it, copying every detail exactly.
They are quite easy to take out and take back to the bench.
Is it not in a conservation area? It should be!

 

[Walfy]

Looks a very nice classy old window - I would have repaired or replicated it, copying every detail exactly.
They are quite easy to take out and take back to the bench.
Is it not in a conservation area? It should be!

I agree - it’s beautiful but client wants to go double glazed and non opening which i think forces my hand somewhat? With a 15mm rebate needed for the edges of the glazing it puts the width of glazing bars at 40mm? minimum whereas if it’s a single pane I can get away with 30.

I’m new to this so there are doubtless better ideas out there!

 

[deema]

Sliding sashes, a lovely project, far more interesting to make that a boring rectangular sliding sash. I’m with @Jacob I’d make an exact copy with the addition of draft excluding strips / brushes and also double glaze it rather than single. I’d definitely not have glazing bars on either side.

 

[Walfy]

 

[Jacob]

I agree - it’s beautiful but client wants to go double glazed and non opening which i think forces my hand somewhat? With a 15mm rebate needed for the edges of the glazing it puts the width of glazing bars at 40mm? minimum whereas if it’s a single pane I can get away with 30.

I’m new to this so there are doubtless better ideas out there!

Know what you mean but I basically turned down jobs I didn't like and specialised only in proper restoration, which doesn't even allow for double glazing (too heavy and too thick glazing bars).
Tell them to have thicker curtains? Or recommend them to a plastic window supplier instead?

 

[deema]

Sliding sashes are notorious for being drafty and rattle in the wind. It doesn’t have to be that way, try highlighting the benefits of modern jade sliding sashes and how much more appealing it will bake their property to subsequent buyers having modern traditional features.

Have you ever tried just to push out a window with just glazing tape? No chance without smashing it. Glazing tape then silicone around the edges of the DG unit and it isn’t coming out anytime soon regardless of what size beading you put on. I ended up sizing my rebates to the minimum size of bar the DG manufacturer would guarantee.