Best way to cut a curve in composite fascia

[lavinpj1]

Hi folks,

I'm building a small hump back bridge in my garden. I've decked the top with composite decking boards and I'm now just finishing off the sides with solid composite fascia board.

So far, the fascia board is rough fixed. Bottom of the fascias line up with each other and the tops are all flush with or proud of the decking boards.

What's the best way to cut the tops of the fascia boards to match the curve of the bridge? I'm thinking either:

:: Mark the curve, number and remove the boards, cut them all with the skill saw. I figured this might be a little inaccurate particularly on the cuts tighter to the edge
:: Same as above but with band saw. I have a cheap band saw but I've not used it in years and I'm not sure I trust myself to do a decent job with it
:: Use the 1/4" router with flush cut bit. Problem here is the gaps between the boards. Router is going to drop down going over those. I thought I could maybe put a tensioned strip of gaffa tape along the edge to bridge the gaps between the boards?
:: Japanese flush cut saw. Would be tricky to get started as I don't have an exposed end to start at
:: Some sort of combination of the above?

Any other thoughts?

 

[foxhole]

Protect boards,Triple tape the ends of the boards, (masking tape). Then fine tooth jig saw. Finish off to posts with sharp fine tooth hand saw .

 

[freddiemercurystwin]

I think I might have extended the board edges over the fascia to avoid having to see that cut edge. Millboard do a flexible edging strip that could be incorporated, not cheap no doubt but there may be others available.

 

[lavinpj1]

fine tooth jig saw

Do you think this will be better than flush cut router bit?

 

[lavinpj1]

I think I might have extended the board edges over the fascia to avoid having to see that cut edge. Millboard do a flexible edging strip that could be incorporated, not cheap no doubt but there may be others available.

The boards are hollow, so the idea of the fascia is to cover the hollow ends. Solid boards do exist but they're mighty expensive in comparison, and I've largely used offcuts from the main deck for the bridge.

I was wondering about flexible edging strip. Eurocell have a 3 week lead time on theirs and I didn't want to wait. I'll check out Millboard

 

[opps]

Are you not worried that it will stick out like a sore thumb once you remove the factory finished edge?

 

[lavinpj1]

Are you not worried that it will stick out like a sore thumb once you remove the factory finished edge?

A bit, yeh... I'm hoping I can sand it down to 1200 grit to get it looking nice again. Not sure what other choice I have, though.

 

[opps]

Protect boards,Triple tape the ends of the boards, (masking tape). Then fine tooth jig saw. Finish off to posts with sharp fine tooth hand saw .

You have more faith in the protective powers of masking tape than me...

 

[opps]

I would be tempted to go with the router. You could use your bandsaw to cut temporary filets to fill the gaps so that the wheel doesn't fall in the gaps.

BTW, looks good thus far.

 

[freddiemercurystwin]

The boards are hollow, so the idea of the fascia is to cover the hollow ends.

Is there not a likelihood of your curved cut exposing the hollows too?

 

[lavinpj1]

Is there not a likelihood of your curved cut exposing the hollows too?

Sorry, I wasn't clear. The decking boards which you walk on are hollow. No need to cut them to a curve as they're laid on a frame of 2x12 already cut into a curve. The fascia board is 15mm thick solid board which will cover the hollow ends of the boards. It's the fascia board I need to cut, to follow the existing curve of the deck boards.

Boards: https://www.eurocell.co.uk/decking-...ided-decking-board-length-3-66m-x-width-145mm

Fascia: https://www.eurocell.co.uk/black-co...ecking-facing-trim-length-3-66m-x-width-150mm

 

[foxhole]

You have more faith in the protective powers of masking tape than me...

Tape just give early warning you are too close to edge .

 

[cdbe]

I'd probably trim them flush and fit composite "skirting" on top - laid flat it will follow that curve. If you don't trust your self with a jigsaw a few multi tool blades will do it.

 

[lavinpj1]

I decided to mark the curve with pen, label and remove the fascias, rough cut them with a band saw, reattach, protect the boards with masking tape and gaffa tape… and then use 1/4” router and flush trim bit. Aside from the absolute barrage of plastic shavings flying towards my face, it worked alright.

The fact the bottom of the fascia doesn’t line up with the wood bugs me a bit but not enough to want to buy another length of fascia

 

[opps]

Looks good. Well played.