Diagnose this weird blue wax stain on epoxy. Please.

I built a standard epoxy lam’d bamboo fish for a person up in SC.  He used some blue colored wax.  The wax seems to have stained the epoxy deck.  It doesn’t seem to have pennetrated the lam onto the bamboo or foam.  The deck is not cracked and you can see the stain is not in lines or strips.  It merely stained the epoxy deck.  He used "firewater’ (wax remover?) after the stain to try and remove the wax and the stain.  But no luck.

He would like to get it off and I’d like to help.  If I had the board I would take off any remaining wax and sand down to the weave, then hot coat again.  In hopes that that would work. 

But, just, wow.  Anyone hear of this before?  I need a clue.  And make it a big one.

(the lengthwise stuff is a rice paper print of a Maori tatoo that was requested by the customer, painfully tedious to apply)


Hi Greg -

I made a board that was glassed with epoxy (not Timberflex or compsand) that developed a single spot that kind of looked like that.  The guy who owned it asked what it was.  I told him I didn't know but I'd be willing to sand down and investigate.  He said never mind.

I'd be curious if it does sand out.  If not, something deeper than the wax is causing it?  

I considered the possibility that some of the watered down spackle I had used was coming to the surface but wasn't able to test my theory.  Was the board in question spackled?

Several years ago I tried to patch a crack in a glass hummingbird feeder by smearing some epoxy on the inside of the crack.  After the epoxy was cured I filled the feeder with red colored sugar water.  After a week or two the epoxy patch became rubbery and turned red.  It was very weird - kind of like a sheet of fruit roll but more difficult to tear.  No one on Swaylocks was much help when I asked about although it was suggested that I had botched the proportions of the epoxy mix.  I don't think that was it since the epoxy was fully cured before I added the colored sugar water. 

In any case, I'd consider the possibility that the epoxy could have absorbed some of the coloring of the wax.  Since wax companies keep their formulas secret we might not ever know what was in it.

Two things: One, as John says, you don't know what's in that wax that could chemically affix itself onto the laminate. Two, the solvents in the wax remover probably took the stain and permeated the laminate further. Many of the ''wax remover'' products are powerful solvents that shouldn't touch a surfboard (unless it's painted with a chemically resistant barrier like Awlgrip or something).

Got me on this one …


maybe try using mineral spirits to rub off

GL, wow.  I have stumped the master.

I don’t have the board with me, but will recommend sanding to the weave and see what happens.  Will share the results.


(yeah, it was RR)

Wonder what the stain looks like under a magnifying glass? Was this on a gloss polish or sand finish?