In this post I will outline my process for finish varnishing the Sage 17 rudders. (read part one here.)
After each rudder has received their undercoat of Interlux Jet Speed they are ready for at least three coats of Interlux Compass Clear. Compass is a UV stabilized varnish, unlike Interlux Jet Speed, and will protect the wood from sun damage.
First the rudders are sanded, lightly, with 220 grit paper. The slight amount of varnish you are sanding should come off in a fine dust. If the varnish is coming off in ‘gooey balls’ it isn’t dry. Stop, wait six hours, and see if the varnish is dry.
Use a tack rag to remove the dust and then wipe down the rudders with a shop towel damp with Interlux 333.
The varnish is applied using smooth strokes. I work in 6″-9″ sections from one end of the rudder to the other. Work quickly to assure you keep a wet edge.
Once the top is varnished I run the brush along the edges. I don’t wet the brush in varnish, I do this step with a ‘damp brush’ just after completing the last section of the rudder’s top.
Now I smooth the varnish on the top of the rudder. I use long slow strokes going from bottom to the head of the rudder.
- When using a foam brush it is important to go slow with these final strokes; if you move quickly the brush can ‘chatter’ or ‘hop’ along the surface. If moving slowly the brush still chatters dip just the end of the foam chip into varnish to make it just damp.
If you look at the surface just after doing these final ‘finish strokes’ you will see slight brush marks. These should settle out in a couple of minutes.
- If the varnish has thickened in the can the brush marks may not settle out. After this coat drys, sand out the marks and thin the varnish. For Compass thin no more than 15% with Interlux 333.
- It is also possible to apply the varnish in too thin a layer, meaning applied to little varnish. This will also leave brush makes. After the coat drys sand out the marks and apply another coat just a bit more thickly.
At this stage of varnishing you have multiple coats to apply and it is not a problem to sand out a mistake as your skill at making a smooth finish coat improves.
Now use a shop towel that is damp with Interlux 333 to wipe the lower edge of the rudder sides.
Allow the varnish to dry, flip the rudders over, and apply a coat of varnish. I find that Compass takes about 6-8 hours to be dry enough to flip over the rudder and do the ‘back side’ (bonus the shop being in Golden, Colorado, is the low humidity and quick dry times). to fully dry Compass takes about 18-24 hours.
Once both sides of the rudder are dry sand again with 220 grit paper, dust, clean and varnish. A minimum of two more coats needs to be applied (giving a minimum total of six coats).
Now you inspect the rudder. Are you happy with the finish? If yes you are done. If not sand, dust, clean and apply another coat.
- For a super smooth final coat sand the prior coat with 400 grit paper instead of 220 grit. Be sure to clean off ALL the dust before applying that final perfect coat of varnish.
That outlines to steps used here at Sage Marine to get the rudders ‘nice a pretty’. The entire process takes a week … thought the time spent sanding and varnishing is only 20 – 30 minutes each day.