Gluing onto BLO'ed MDF?

[rick carpenter]

Well, my OCD may have failed me this time. I put a couple of coats of BLO/varnish on an MDF base for a router table before gluing on my leveling shims. Can I reliably glue wood shims onto the 'treated' mdf or should I start over? Not much invested in time or material for this component, but again my compulsion to make it work will outweigh the logic of starting over.

[Mike Henderson]

My experience is that the glue won't stick very well, unless you can sand the BLO portion off to get to raw MDF.

Mike

[glenn bradley]

My experience matches Mike's. I would reinforce and adhesive attempt with something mechanical; brads, screws, etc. I BLO my work surfaces so that adhesives won't stick. If you did a light wipe of BLO, the penetration may not be too deep and you could sand or scrape to raw material. If you flooded the surface as I did for my workbench, the penetration is pretty deep and so, reaching raw material may be unrealistic. JMHO.

[Rich Engelhardt]

As long as the BLO/varnish is dry, I don't believe you'll have any problems.
Just use an all purpose adhesive instead of wood glue.

[Bob Wingard]

Therein lies your problem ... BLO never really dries ... it migrates deeper into the surface and just sits there, waiting to do something nasty to your project at a later date.