Is there a way to strengthen the fibers inside a pilot hole drilled into spalted wood, so they can be more sturdy after tapping with a stopper mandrel? Just want to avoid thread failure as often as possible in this light wood.
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Beefing up spalted fibers before tapping with stopper mandrel??
- Thread starter Jamie Straw
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You can use CA to make the threads stronger, still not bulletproof.
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For softer woods, you can drill slightly oversized and then strengthen with CA as Gerald suggested before tapping.
See page 2 of this chart. The chart shows drill sizes for 50% and 75% thread engagement. I'm not positive, but the 50% thread engagement might be less likely to tear out during tapping. Alternatively, you could drill for a snug (not tight) fit to the screw without tapping if the wood is soft enough to comply with the stopper threads. Whichever method you choose, I would put a little super thin CA in the hole. If you are brave and quick (AKA foolish) you might put just a bit of CA in the hole before final installation. If you aren't fast enough you might regret trying that.
See page 2 of this chart. The chart shows drill sizes for 50% and 75% thread engagement. I'm not positive, but the 50% thread engagement might be less likely to tear out during tapping. Alternatively, you could drill for a snug (not tight) fit to the screw without tapping if the wood is soft enough to comply with the stopper threads. Whichever method you choose, I would put a little super thin CA in the hole. If you are brave and quick (AKA foolish) you might put just a bit of CA in the hole before final installation. If you aren't fast enough you might regret trying that.
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Is trere enough room to glue a larger hard close grained wood dowel and then drill and tap that?
Stu
Stu
Dowel a good option
This may be the best shot. If it was just strengthening the stopper grip itself, CA would be fine, but this is regarding having stronger wood when I tap with the mandrel, after which the stock goes on the lathe. Of course, have to be able to remove the mandrel eventually.
I've only had one failure out of 5 stoppers turned, so it may not be a big problem in the long run.
This may be the best shot. If it was just strengthening the stopper grip itself, CA would be fine, but this is regarding having stronger wood when I tap with the mandrel, after which the stock goes on the lathe. Of course, have to be able to remove the mandrel eventually.
I've only had one failure out of 5 stoppers turned, so it may not be a big problem in the long run.
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Oak dowel worked great
In the spalted stopper that got bunged up, I drilled it out and glued in a piece of oak dowel, flush-cut it and re-drilled. It worked just fine. My love of spalted wood is going to cost me time, LOL. I may routinely use oak on the especially light ones.
In the spalted stopper that got bunged up, I drilled it out and glued in a piece of oak dowel, flush-cut it and re-drilled. It worked just fine. My love of spalted wood is going to cost me time, LOL. I may routinely use oak on the especially light ones.
john lucas
AAW Forum Expert
If you really really love spalted wood. And I mean really really in terms of dollars look into the Cactus Juice wood impregnation. It solidifies the wood so it turns like plastic and as a bonus you can add color to the Cactus Juice and it will add some color to the porous areas. I haven't used it myself, it's not inexpensive. But I have seen some incredible results. http://www.turntex.com/index.php?pa...egory_id=144&option=com_virtuemart&Itemid=121
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Wood stabilization is somewhat complex require vacuum, baking, Makes a mess.
The results are great! I have seen two demonstrations on doing wood stabilization.
Cactus juice costs a bit and you will likely waste a lot learning to use it.
Mike Marek, a member of our club, did a terrific demo a few months ago on wood stabilization with cactus juice and one casting with alumalite.
If you have a terrific piece of wood mike offers a stabilization service.
Mikes web site has a lot of nice things.
http://www.thewoodartiststudio.com
His wood stabilization service
http://www.thewoodartiststudio.com/wood-stabilization-service/
A couple of years ago I saw a demo by Jeff Jolleff. His method was low tech. He put the cactus juice in a jar, added the wood, attached a wine vacuum hand pump, pulled out the air, air bubbles come out of the wood, cactus juice goes in, wrapped the wood in aluminum foil, baked it in a toaster oven, the heat cures the cactus juice he then pulls the stabilized wood out.
I would send my wood to mike .
Al
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I should add that stabilized wood is a lot like plastic. But it is hard and turns well.
It will make crumbly wood easy to work.
A product I have used is Pollyall 2000.
http://www.polyall.com
It is a two part resin. Very thin. I penetrates the surface. It has a short working life like 90 seconds so you mix and apply.
I used it when ,along piece from historic Wye oak. Got a rough shape with lots of tear out. Wiped on the pulls all then turned the surface down a bit wiped on more pollyall because you will cut it away since it only penetrates up to about. 1/4"
It is pain to use but gives great results. I had to make something from rotten wood.
Have fun,
Al
It will make crumbly wood easy to work.
A product I have used is Pollyall 2000.
http://www.polyall.com
It is a two part resin. Very thin. I penetrates the surface. It has a short working life like 90 seconds so you mix and apply.
I used it when ,along piece from historic Wye oak. Got a rough shape with lots of tear out. Wiped on the pulls all then turned the surface down a bit wiped on more pollyall because you will cut it away since it only penetrates up to about. 1/4"
It is pain to use but gives great results. I had to make something from rotten wood.
Have fun,
Al
Wow.
Hmmmm, I might not love it that much, at least right now.
Interesting stuff though. Might be able to sell the small bottles (without activator) as a miracle health supplement. Gotta be a keen turner to invest in a vacuum set-up and such. Will keep it in mind.
Hmmmm, I might not love it that much, at least right now.
Interesting stuff though. Might be able to sell the small bottles (without activator) as a miracle health supplement. Gotta be a keen turner to invest in a vacuum set-up and such. Will keep it in mind.
That looks promising, Al, especially for small objects like stoppers. The wood I've used recently isn't really rotten or super-punky, but the end-grain especially doesn't turn well, and occasionally there's a pin-hole or slightly bigger void. Before I try a plastic filler, I might wet-sand with Watco and see what that does. Also wondering if I turned to within ~1mm of finished, and applied some CA (say to the top of the stopper), let it set and then turned the last mm, would the CA settle in the tiny void and provide a smooth surface.