Raising wood grain

[Biomorph]

I would like to raise the grain on the end of logs without using a sandblaster [if, in fact, that would work anyway]. On end grain I'd like the concentric growth rings raised. Are there chemicals that would do this? You can't easily find this effect in the woods, where any grain raising is likely to appear coincidentally with terminal rot and the sculptured driftwood look is not what I want either. The growth rings are harder, and there might be some way to dissolve out the wood between. I've tried a torch, but I seem only to get uniform char. Maybe I should take a Dremel and cut out the softer wood, but that's not easy, and the result would not have the out of nature feel that I am looking for.

[jOe~]

Try a large, wide, soft wire wheel on a drill.

[Mack]

You might try the torch in conjunction with the wire wheel: the torch will char the surface and the wire wheel will pull out the softer wood between the rings and leave a ridged surface. Finish sanding will get rid of any char left on the ridges.

[mavigogun]

I've read about basting the wood with gasoline, burning, then wire brushing. Another source uses water- soak the wood to swell the softer fibers, then wheel/brush/steel wool away the softer material, working with the grain; for faster results, use steam. Another source referenced a technique employing horse dung and sand used at the Disney parks.

[raspero]

I think you would be happier with the results obtained with a sand blaster. You have exquisite control, by varying the pressure, the blasting media, and the technique. It doesn't take much: a 20 dollar Harbor Freight siphon blaster and a source of air. If you don't have a compressor ask one of your construction acquaintances to let you use his for an hour.

Richard

[jOe~]

The $20 HF siphon blasters don't have the poop to do the job, neither do construction air compressors. Their $80 blaster with about a bigger 60-80 gallon ($400-500 minimum)compressor would begin to work but that creates one heck of a mess and slow going. Sand blasters require huge amounts of air.

[raspero]

I have been using siphon blasters for 15 years with good success, mostly in a blasting cabinet. They require somewhere between 40 and 100 pounds of pressure, depending on the force you want to exert.

Yes, they do require a fairly large amount of air, but only if you plan on continuous usage; my 5 hp compressor makes more than enough for that. When I first built the cabinet I used a compressor with a 1 hp motor. I could blast for a few minutes and then I would wait for a few and let the air build back up. For the type of work Biomorph is wanting to do, that should be plenty good, unless of course he has an old growth Doug Fir log 5 feet in diameter. In that case he'd want one of those machines you see out on the highways sand blasting bridges.

Richard

[Mack]

I mentioned the torch/wire wheel(or brush) method because I recall watching a wood worker years ago making a table with 2x8 or 2x10 wood planks for the top, probably pine or doug fir, 'distressing' the wood. (I think 'distressed wood' was big back then.) He would play a torch across the wood charring it and then with a firm wire brush would scrape the charred surface in the direction of the grain, which resulted in ridges because of the different hardness between the grain. He made the grooves quite deep on the top, the edges, legs ,supports everything,and then would sand, stain, and resin coat the whole deal.

[Nelson]

Bio, I have yet to find out too what could do that job, and after serious looking into subject, finally found the right receipe. Namely, there`s no chemical that can digest wood preferencially, disolving soft wood and leaving that harder one corresponding to knots, and harder growth rings. In woods like pine, charring carefully (not with torch ! as this may be employed for touch-up areas) gives you a darker, country old look, if that`s what you`re after.For a country look job, it helps if the wood is somewhat dry, mixing diesel and gasoline at a 80-90/10-20 % ratio, soak one side and set on fire, put out, and wire brush. Better yet, if afterwards give it a chorine wash and put it in the sun. Compact (hard) woods don`t work well with burning technique. The trick is to let wood loving organisms digest the cellulose of softer wood, then and only then will sand blasting work. And just hand wire brushing cleaning crannies and nooks with anything that fits you. Sand blasting alone got to be VERY powerfull, and it`ll just mess up the wood raising splinters and fucking up the whole thing. Bury wood in a shady ground keep it moist, be patient and enjoy life, the result is easy and nothing will match

[RWJR]

if you uses a cutting torch and hold the tigger as you burn , it will quickly blow away the soft wood and expose the grain, You better be in a safe area because sparks will fly and openings in your protective clothing will be found !

[GlennT]

Originally Posted by RWJR

if you uses a cutting torch and hold the tigger as you burn , it will quickly blow away the soft wood and expose the grain, You better be in a safe area because sparks will fly and openings in your protective clothing will be found !

Given your mastery of the blow torch and extraordinary usage for carving steel, and now this advice, I'm wondering if the blow torch is your all-around go-to tool for many occasions, like for cooking burgers, trimming toenails, signing tax forms, etc.?

[RWJR]

well, I do light the grill and have the coals ready in about 60 seconds also good for removing the sprues from iron castings, fast and blends the surface closer to the original sand texture. Often its hard to blend the surface after the grinder.