How to restore / clean old timbers?

[PILOON]

I was once asked to refinish a 40 year old weathered log cabin, it was 36 X 40 ft.
Rented a mobile compressor (about 150CFM) and appropriate equipment plus 20-25 bags of sand blast media.
Job proved to be a piece of cake.
Completed the job within 8 hours.
In no time at all I learned to master techniques * and the finished product was simply awesome, logs retained aged look and all crud and old finish just went away.
The only negative is that any punky or dry rotted wood will really get chewed up while solid wood turns out great. Just like new wood.
After that experience I tackled various pieces of furniture with equal success.

* basically started holding the jet far off and worked in closer always in a sweeping motion so as not to 'dig in' removing as much or how little I wanted.
Masked windows with duct tape which bounced the sand away. For general masking I merely held a smallish piece of plywood (like 12" X 24") in my free hand to deflect sand media away from areas that I did not to blast.

 

[Danno1]

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Piloon,


You used regular blast media? Like Black Beauty?

I would think you'd need something like ground walnut shells or even dry ice to not damage the wood.


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[forgeblast]

I heard corn cob for wood. cleaning old post & beam [Archive] - JLC-Online Forums talks about different ways to clean them.

 

[Greenland South]

I have used a soda blaster for cleaning old wood. Not toxic like the silica sand used in sandblasting. Way less damage, you can actually clean paint off glass with it.

 

[PILOON]

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Piloon,


You used regular blast media? Like Black Beauty?

I would think you'd need something like ground walnut shells or even dry ice to not damage the wood.


.

I would have thought it was needed.
It had just so happened that the local rental yard was blasting some equipment near a wood wall and I asked if OK to try my hand at it. The brief test proved good so I rented the compressor and gear.
I used a sand media, starting with nozzle maybe 12" away and moving in closer but always moving in a sweeping motion going back if needed.
The logs in question had an epoxy varnish with many dark spots from mildew. Joints were caulked as well.
Once blasted ALL the logs looked just like new except where there was dry rot. The rotted areas were just so soft that the finish was very pulpy looking.
I later even did some tables and other furniture.
Oak and maple looked like just ready for 150 grit sanding and soft woods look, well like sand blasted. LOL.(or old driftwood only not grey)
An oak piece (fancy carved table base) simply was awesome. It had as much as perhaps 7-8 oats of different paints and turned out just great.
Remember, you can vary distance, motion as well as pressure so you have great control.
Soft woods will leave fibers while harder woods give best results.
Naturally you do want to hand finish for the nicest texture. For crevices steel wool is good and most flatter surfaces sandpaper to the finish/grit you prefer.
The big thing is FAST thorough 'down to bare wood' and honestly more cost effective than any strippers would be.
If I recall, that log cabin used about 25 bags of media which was a white sand. Sorry don't recall the grit size but seem to remember it was about $6.00/20 kilo bag.
They did say that for wood to use fine to medium grit.
To this day I would love to have a 50 CFM compressor for that sort of project but that luck has just not happened.