Unexpected result using Seal Coat

[Packard]

I use Seal Coat as a sealer/primer for all my clear finishes.  It seals the wood, prevents grain raising, minimizes subsequent finish absorption for faster finish build, and dries in an hour. 

I usually sand the wood to 220 grit, stain and then apply the Seal Coat.

I am making a pour over coffee maker as a gift for a friend.  I’ve made these in the past and they have always been well-received. 

I don’t know why I decided to sand progressively to 800 grit, but I did.  The red oak felt silky smooth prior to applying the finish.

I then applied an oil based stain.  And then applied a wipe on coat of Seal Coat.  This is a very light coating, and I am able to apply it very evenly using the wipe on process.  I applied full strength. 

Typically that results in a satiny appearance that I would scuff up with 400 grit and then apply the top coating (in this case, oil-based poly).

Strangely, the Seal Coat finish was extremely shiny—looking like a violin finish.  Except that shellac would not stand up to the environment of a coffee maker, it looked ready to present.

It is surprisingly difficult to show how glossy it is in a photo.  This is my best effort.

Does anyone know why the sanding to 800 grit resulted in the glossy first coat with shellac?  I have never read anything that would suggest that effect.

As an aside:  All the previous versions were made with dovetail joints.  I used dowels because I have been using dowels for my cabinet work. 

Secret:  Dovetail joints are much, much faster to excecute.  In the future I will only use the dovetail jig for these coffee makers.

 

[Crazyraceguy]

I would guess that it was the sanding to 800 that caused this. 800 would be nearly burnished closed, so the finish doesn't actually get absorbed, it sits on top, like a second coat would.

 

[Packard]

That makes some sense.  Would it mean that the adhesion value that Seal Coat adds, would be somehow less effective?

Is the Seal Coat sitting atop the surface and not being absorbed into the wood mean that it has less adhesion? 

When I get a chance, I will make a comparison test.

 

[Packard]

Typically Seal Coat dries in 20 minutes to an hour.  So over night is going to be fully cured.

I applied the first coat of wipe on poly (50% Minwax oil based poly/50% mineral spirits).  This is a formulation I have used with excellent results for years.

I applied it 12 hours ago and it is not close to cured.  Tomorrow is supposed to be be sunny.  I will leave it in the direct sun all day.  Sunlight seems to hurry the curing.

I don’t see how over sanding will have caused this.

I will make a side by side test later and report.

 

[Packard]

I did the test. I sanded one 3-1/2” x 6” piece of maple to 220 grit, and a second identically sized piece to 800 grit.  Bot pieces taken from adjacent sections of the same board.

I wiped on Seal Coat on both, attempting to apply both pieces in an identical fashion.

The results:  Both pieces looked and felt identical.

I lightly sanded both pieces with 400 grit and the wiped on oil based poly.  Again, no perceived difference.

I will have to repeat the test with red oak to see if that replicates the effect I saw on the coffee maker.

The coffee maker was well received, by the way. I include a can of my favorite coffee (Illy), some filters and ceramic drip cone.  I’ve made about a dozen so far.  It makes a nice gift.

 

[Packard]

I tried to repeat this effect several times using different materials and sanding to 800 grit.  In each case, the 220 grit sample ended up looking identical to the 800 grit samples. 

I was never able to repeat the original high gloss results I had with the coffee maker.  A puzzler.