Fisheyes in BoteCote Epoxy over Philippine Mahogany
Posted: 19 Aug 2021, 15:02
May I have your advice please? Long story short....
For the past 3 years I've been building another Glen-L Crackerbox 16' powerboat - cold moulded hull skinned with marine ply and lamined in 48 x 16' strips of 3/16" Philippine Mahogany - glued with BoteCote and nailed with 18 gauge Raptor polymer nails.
I painted the raw hull in a slurry of watered down Timbermate natural finish woodfiller (to fill in the grain) then sanded it off and hand rubbed on thinned Jarrah Prooftint (thinned with metho). It was a perfectly smooth flawless surface - couldn't even see the nails.
Here's where my problems started... I've used Bote Cote two part epoxy as a top coat on other projects with great success, however after rolling on the first coat then tipping it off with a 3" foam brush...fisheyes started appearing everywhere...over the entire hull. I approached the local BoteCote distributor who checked my batch number with head office and advised that there must have been surface contamination present on my hull.
I washed down the hull with Acetone then scrubbed down the hull with hot soapy water and applied a second coat... with the same result to a lesser degree. I'm now up to coat #5 - wet sanding between coats to greatly minimise the fisheyes without sanding through into the stain...getting less and less blemishes each time. The timber grain looks superb. My aim is to achieve a deep clear finish (initially expecting to do 10 coats) as the end result but am wondering if I should switch to using multiple layers of clear varnish over this to finally eliminate the fisheye remnants - alternatively I could sand everything off back to raw mahogany and start again...but I'm buggered if I know how any contamination happened in the first place.
I'd welcome your collective advice please.
For the past 3 years I've been building another Glen-L Crackerbox 16' powerboat - cold moulded hull skinned with marine ply and lamined in 48 x 16' strips of 3/16" Philippine Mahogany - glued with BoteCote and nailed with 18 gauge Raptor polymer nails.
I painted the raw hull in a slurry of watered down Timbermate natural finish woodfiller (to fill in the grain) then sanded it off and hand rubbed on thinned Jarrah Prooftint (thinned with metho). It was a perfectly smooth flawless surface - couldn't even see the nails.
Here's where my problems started... I've used Bote Cote two part epoxy as a top coat on other projects with great success, however after rolling on the first coat then tipping it off with a 3" foam brush...fisheyes started appearing everywhere...over the entire hull. I approached the local BoteCote distributor who checked my batch number with head office and advised that there must have been surface contamination present on my hull.
I washed down the hull with Acetone then scrubbed down the hull with hot soapy water and applied a second coat... with the same result to a lesser degree. I'm now up to coat #5 - wet sanding between coats to greatly minimise the fisheyes without sanding through into the stain...getting less and less blemishes each time. The timber grain looks superb. My aim is to achieve a deep clear finish (initially expecting to do 10 coats) as the end result but am wondering if I should switch to using multiple layers of clear varnish over this to finally eliminate the fisheye remnants - alternatively I could sand everything off back to raw mahogany and start again...but I'm buggered if I know how any contamination happened in the first place.
I'd welcome your collective advice please.