We are building some small cabinets that are specifically made from baltic/russian birch due to some of it's characteristics (rigidity and core quality).

The "football" plugs however are giving us a little grief in the paint booth. The client isn't thrilled with the way the outer perimeter of the football plug can telegraph through the finish.

We spray a fairly high solids CV, and we've tried every trick we know to hide the footballs, and the final result is hit or miss. Some disappear totally, but most you still see a bit of a witness to the oval shape even after 3 coats, sanded aggressively.

We've tried using putty, bondo, etc to fill in that tiny hairline ring that can result but nothing is a sure-bet.

We're not exactly keen on switching materials to something like common domestic C3/B2 Maple because we need the core integrity of the Baltic birch.

Anyone have any tips on this?

Spec a higher grade of Russian birch. BB/BB can include patches and putty fill but B/BB will have one clear face.

if you have to use that material you can always lay up the end/seen panels with a backer sheet or liner material then paint that. will come out perfect.

Drip cyanoacrylate glue along the joints, let is set fully, and then sand. Re-drip any areas that are not bonded 100%. Your aim is to bond the entire football at the surface - the joint between faces.

But buying better Baltic Birch brings better boxes, as I always say.

David Sochar
Bravo maestro
The finishers I work with would take that trade secret to the grave.
If they had that knowledge they wouldn’t share it.
Respect from Chicago
Adam

Matt,
Check your specs on ordering. B/BBB would be your best choice. The BBB has no patches on that side. We use lots of Baltic Birch for one company that we manufacture for. Sometimes when we can't get B/BBB and have patches on the face side we will use Bondo auto body filler. If the patches are not too bad we can use auto body glazing putty. Both work great and we have never had a problem with bleed through.

Honestly a good finisher can polish a turd.... In this case your finisher is not using a good enough primer surfacer or he isn't getting enough millage laid down. I would build up primer coats well past acceptable dry mills, let cure and then proceed to rough sand back flat. This process, if done correctly will fill any voids and render the surface perfectly flat and no voids after it's sanded back thoroughly. Get the primered surface perfect and your topcoat will lay out beautiful... IMO

Just to clarify, B face is free of splits or patches, BB can have putty and patches. I have never encountered a BBB designation but confusion might exist because I hear contractors calling for triple B at the order desk when they want B/BB.

Understood, gentlemen. Most of what you're saying is what I expected.

Let me feed this info upstream.

A couple of different approaches, piling on primer and grinding it down to smooth, and using CA glue to skim over and to fill in the tiny seams.

For me, the CA glue is more production friendly than is laying down an overly thick coat of primer. Similarly, when prepping furniture for delivery and there's a bondo or epoxy putty repair to be done, the CA glue is a go-to to skim over the bondo or epoxy putty fill. It acts as a barrier coat and hides any seams that seem to want to telegraph through the topcoat no matter how smoothly sanded.

Each option for dealing with these fills has its tradeoffs.

Does everyone don a mask with a cartidge filter when using CA glue? Don't breath that stuff, even when you're sanding it. It's pernicious and nasty. Wear your mask. If you have a beard, either shave it or wear a fresh air supplied positive feed respirator. Safe finishing is no accident.

Don’t huff Cyanoacrylate
Ok?
A