BLO Drying Time?

[Tom Slick]

How long do I need to wait for coat of BLO to dry before spraying pre-cat lacquer?

Thanks

[jabe]

In my area, straight BLO does not dry for months because of the humidity in the tropics. I usually mix 16 oz. BLO with 16 oz. turpentine and a cap full of Japan Dryer b4 applying it to the wood. The turpentine acts as the carrier for the BLO to penetrate into the pores of the wood & the Japan Dryer helps it to dry, usually overnite. I hope U live in a dryer less humid place so it'll dry.

[Daryl]

I use 50/50 blo and mineral spirits. I put it on heavy and come back an hour later and wipe off all the excess and give another coat the next day or so. Seems like it is all dry a couple days later, I wait a week or so to top coat it with poly or shellac.

[Uncle Cracker]

Because of the humidity here in FL, I only use BLO for finishing pen turnings on the lathe, and it must be used in conjunction with CA glue.

[themachine]

Some of these replies caught my technical eye, so to speak. Boiled linseed oil does not dry in the traditional sense as there is little to no water in it. Humidity iin the air should have no impact on curing of BLO. The oils in BLO actually oxidize in the presence of oxygen to polymerize into longer chain fatty acids or hydrocarbons, thus changing BLO from liquid at room temp to solid. That is really the so-called drying. Temperature is much more important at controlling the rate of conversion. I personally would wait 1 week before top coating, assuming you removed excess BLO after application.

[Uncle Cracker]

Some of these replies caught my technical eye, so to speak. Boiled linseed oil does not dry in the traditional sense as there is little to no water in it. Humidity iin the air should have no impact on curing of BLO. The oils in BLO actually oxidize in the presence of oxygen to polymerize into longer chain fatty acids or hydrocarbons, thus changing BLO from liquid at room temp to solid. That is really the so-called drying. Temperature is much more important at controlling the rate of conversion. I personally would wait 1 week before top coating, assuming you removed excess BLO after application.

What the finish guru at WC here told me is that the humidity hereabouts will contaminate the oil while it cures and leave a milky finish. It's really not about drier air speeding the cure.

[Richard in Smithville]

Straight BLO-one week minimum

BLO/MS-three to four days