Interested in Wog's secret wood sealer but a question.

[artificialreef]

Hi Fellow iboaters. I always liked alternatives to shelf bought products. I made my own natural weed killer (mixed results) and dig WoG's secret formula wood sealer. I had the mineral spirits and linseed oil on my shelf so i went out to purchase the spar varnish. The product I picked was called Captains Varnish 1015 Z*Spar by Pettit. Not the most expensive on their shelves but my plywood will be covered in vinly (Its just for the bolster) so i dont think i need the best. Not really exposed to the elements alot. After reading the ingredients i see the following.
Alkyd Polymer.
Mineral Spirits
2-Propoxyethanol
Xylene
3 questions, with WoG's secret formula we are cutting the varnish with linseed oil and mineral spirits. The ingredients already show mineral spirits.
Arent we just dilluting an allready decent waterproofing formula?
Wouldnt it be better to just use the straight spar varnish?
Lastly the captains varnish doesnt call itself spar varnish but i did purchase at a marine store. I asked them if it was spar varnish and they thought it was but it was just a kid that answered my question. I figure any marine varnish with uv protectants and waterproofing would be spar varnish since the spar in the name is just a boat part reference.
Thank you for your advice in advance.
AR

 

[Woodonglass]

For your application it really doesn't matter what varnish you use since it won't be exposed to the elements. You want it to be thin so it will soak deep into the wood. The key is to finish with 2-3 coats of full strength varnish

 

[Scott Danforth]

Your over thinking it. Follow the mixing instructions, then cover with 3 coats of spar varnish

 

[artificialreef]

I have a tendency to do that. Over think things. I am reading between the lines of WoG's comment and now think the further thinning of the spar varnish is to let it penetrate the wood as opposed to sit on top of it. Dammit, already put 2 coats of full strength on 1 bolster. Going to thin it with WoG's formula now. Thanks WoG and Scott. I love this place. Cant believe i have been working on this planter for 6 years. 95% complete now.

 

[Woodonglass]

Here's how it theoretically works. Thinning the BLO and the varnish allows it to penetrate really well. When it evaporates the molecules of the BLO tend to expand which fills all the pores of the wood down deep and the varnish then forms a thin Plastic like barrier as well. When you follow up with 3 Full strength layers of varnish, the first one penetrates a bit and seals the top layer and then 2 more really give it a good barrier coat. As long as you don't poke holes in it with out sealing them it should last a very long time.

 

[artificialreef]

Whoao, I must not have the whole secret formula. I didnt read where you coat it with 3 coats of full strength. I did a search for your formula and found 1 part boiled linseed oil, 1 part spar varnish and 2 parts mineral spirits. The info i dug up didnt say follow with 3 coats of full strength spar varnish. Is that what the procedure is? How many coats of the thinned sealer before the 3 coats of full strength? Hmmm, i think it said something about until it pools and no longer soaks in. Then hit it with full strength 3 coats? Bummer, i just jacked up one side. Oh well, its still has full strength varnish on it. I will do the 3 others like you instruct.

 

[Woodonglass]

Here ya go...

 

[jonny rotten]

Here ya go...

I just applied this last week to sanded 3/4 plywood. It took nearly 3/4 a gallon on one side alone! It's been drying for 7 days in 80 deg sunny weather. Think that's enough? It seems dry but I can still smell it on the wood. Will any polyurethane work as the final sealer or should I use the Helmsman spar urethane I used in the mix?

Also I'm carpeting over it, I read in another post you mentioned to use 6700 adhesive so the glue doesn't eat the varnish. Something about that adhesive being water based? It that still the best option?