Oil (Tung, linseed) finishes are penetrating finishes, they are supposed to soak into the wood and not sit on top of the wood like a film finish (shellac, lacquer, varnish). You apply the oil and it soaks into the wood. But not very far, as you know if you have ever chipped the finished wood. If you have ever seen Woodsure (amazing stuff), you know it is possible to infuse Acrylic resin throughout a piece of wood. In Bob Flexner’s Understanding Wood Finishing, there is a picture of a piece of oak sitting in a puddle of linseed oil and oil has migrated to the other end of the block (it looks like over 5 inches). Infusing wood with [linseed] oil doesn’t add any protective features, it does deepen the color. Here’s how I do it.
I have a small vacuum pump and a vacuum flask (which has a valve built into the lid). The wood is put into a bucket of oil, a 15 in (of mercury) is pulled, the flask sealed, the pump shut off and I got do something else for a while. You can see the bubbles of air leaving the wood. I soak the wood anywhere from an hour to most of the day. It is interesting, after the wood is removed from the oil, the oil continues to soak in, and the end grain dries out. Wipe off the excess oil and let the oil start to cure. Don’t heat or you get lots of bleed out. I typically put the wood in some sawdust over night, then let it sit for a couple of days and varnish.