Will Sawmill Blade Lubricants Cause Trouble with Finishes?

but here's a tip on how to test substances for troublesome interactions with finishes. April 9, 2007

Many sawmillers are debating if using diesel/kerosene mixed with chainsaw bar oil will cause a problem with finishing the lumber after it is dried, planed, sanded, etc. This lube is used to keep bandsaws cool and sap-free during milling. It's typically used at a rate ~1 drop every minute. But, being a miller myself and witnessing the realities of the job, there could be times when the saw is idled for unknown reasons throughout the day, and it could accumulate in larger quantities or even spot the rough lumber. I've been afraid to use it, so instead, I use water or a water and dish soap/Pinesol mix. The debates rage on and this topic is often discussed without a clear winner on either side. I would like to know if any of you professional finishers have, or suspected, a problem with this?

Forum Responses
(Finishing Forum)
From contributor W:
Haven't had or suspected that to be the problem when problems arose...

From contributor C:
Oh! So that's what's been causing all those fisheyes in my finishes! Just kidding... No way that minor contamination makes it through the planing process. And the sanding is an extra safety net besides. My finishes are more likely to be impacted by the forklift driver's oily foot tracks, but I can handle them too. Relax and keep your saw cutting slick. I'd rather have a decent cut than avoid some miniscule oil droplets on the high spots of the wood (which will be planed away anyway).

From contributor J:
I have to agree with the above posts. Unless the lumber is getting drenched, I don't think it would be a problem. Most of my 4/4 rough comes in about an eighth inch strong. By the time I'm spraying a finished product, it's 7/8" or less. That means an eighth inch of wood off of each side is in the dust collector, along with any oil drippings.

From contributor E:
There are a gazillion things that can cause finishing problems, especially fisheyes. At one of my accounts, we used to take a piece of maple veneer, white wood sand it and then spray it with sealer. The piece would be sectioned off and we would test various products to see if they would cause fisheyes. These products would be deodorants, hand creams, suntan lotions and various other skin care products. The section used then would be sealer sanded and the product applied directly to the part and then top-coated. If it caused fisheyes, that product would not be allowed to be used by the employee or in the plant. I found this a very useful tool in not only this customer's facility, but a lot of other accounts I called on. This list was used and updated constantly. You can test any product with this method.