Epoxy or Varnish?

[JBM]

How do you tell the difference? I'm re-finishing the bottom of an old Fernell and not sure whats on it. I plan to re-finish with West sys. I am told epoxy won't adhere to varnish. Is there a simple test, or do I have to take it all the way down to bare wood? Thanks

[Dew1us]

i'll be able to tell you what to use. Just need to know possible year and who has owned it. But most of the boats had west systems on it.

[johnsonm50]

Paint remover usually makes short work of varnish, it would need to be removed anyway. I dont recommend it near seams or where glue could be effected. Varnish unless its old will clog sandpoaper while epoxy is hard to sand. West epoxy is good as a sub finish and a strong adheiseve. [Sunshine ruins it unless its coated with something like UV protecting ext. varnish or paint]. They will stick well even tho epoxy shouldnt be put over them.
I use west system as the glue to assemble a boat and the sub finish, that makes for alot of sanding: eek:. West needs to be a low humidity application with thin coats [sanding between required]. I like to use -for all paints- type foam rollers for large areas, brushing doesnt work well. From mixing to application needs to go quickly. The epoxy will take 2-4 hours to dry applied but will activate fast in bulk. That also means the ecxess in the roller will activate faster. You can get slower dry hardener but it still sets up faster in bulk. Have some spare rollers near cause the stuff kinda messes them up. I hope this helps rather than seem too much of a pain, I think its worth it long term.

[crfabbro2F]

Put some acetone on a rag and wipe it on a small area, and if its
regular 1-part varnish it will eat into it. If it is epoxy there won't be
any reaction. Another method is to fine sand an area and observe the
smell of the dust- epoxy dust smells like epoxy ect...

[ZUL8TR]

refinish options

How do you tell the difference? I'm re-finishing the bottom of an old Fernell and not sure whats on it. I plan to re-finish with West sys. I am told epoxy won't adhere to varnish. Is there a simple test, or do I have to take it all the way down to bare wood? Thanks

I would not put epoxy over varnish only varnish over it. For best results the old varnish should be removed with paint/varnish remover then sand and clean wood and then apply epoxy and hope for no fisheyes (non will happen if you really clean the wood). It is best to apply 3 coats epoxy which builds enough to provide a good base for sanding to a nice level surface for the varnish or auto clear top coat. If the epoxy system you use has no amine blush you can do the build coats without sanding between while the epoxy is just dry to the touch (several hours depending on temp and humididy) but not fingernail hard. This allows for only sanding the top coat for the clear coat and a whole lot less work.

Then let epoxy dry for at least a week. Varnish at least 3 coats if no buff process or at least 6 coats with buff process and wet sand between with 320. If a flawless mirror finish desired and you use the right varnish you can buff out the varnish to remove unavoidable dust and stuff. I use Pettit Captains 1015 marine varnish and some Pettit brushing thinner 12120 for good flow out. After at least a month of drying can be wet sanded with 1000 then 2000 and buffed with really fine polishing compound. You can hasten the varnish cure for buff process if after a week you wet sand with 1000 and let that surface air dry for 3 or so weeks then continue with the 1500 and 2000 then to ultra fine polishing compound. 3M makes a good one but I have had success with Turtle Wax ultra fine polishing compound for clearcoats. Hard work but a flawless mirror finish will result.