Decking handrail

Hello, I am looking to replace decking handrail that I have. The previous owner put screws through the top of the handrail into the spindles and it would appear that water seeping through a handrail tends to rot it after a year or two.

So - I now have a new handrail. In the grove is a fillet piece, but how do I attach all this to the spindles?

Use dowel rods.

i.e. small 2cm holes in underside of the handrail (not all the way through to the top). Then holes in the center of the spindles at the correct debt (depending on the legth of the dowel rods you are using). Held in with good weatherproof wood glue.

This way you don't see any screws form the top. The bottom you can repeat or use screws through the foot rail into the center of the spindles for extra strength. Depending on the length of the hand rail you may need a few extra pairs of hands to assist mounting the top on once the dowels are in place.

Place another piece of long wood on top of the handrail and ease the dowels into the spindles with a soft mallet.

Thanks - how does the fillet piece fit together with dowels? I thought you perhaps screwed the fillet into the spindles (from the top) then slotted the fillet into the handrail grove?