Posts: 10,742
Threads: 1
Joined: Jan 2006
Location: Orlando, Florida
I went and pulled several species from the wood database and compared density to both Janka Hardness and Crushing Strength. Both hardness and crushing strength are proportional to density - the higher the density, the harder the wood and the harder it is to compress the wood. There's some irregularity around the 0.55 to 0.60 density range, but the trend is about a straight a line as can be drawn from the data. In my case, cocobolo has an even higher density than ebony, and it's very hard. What I have learned from this discussion and my research is that I am better off either kerfing the tenon or grinding off the wings and using epoxy to set the shafts, or both. Both are acceptable methods, since they both achieve the same results.
Still Learning,
Allan Hill
Posts: 21,259
Threads: 2
Joined: Mar 2009
Location: IA
Shop Dad said:
Would anyone know of a good tutorial or guidelines on offset turning handles with a triangular form? At the 2015 symposium I got hands on with David Ellsworth's tool handles for Robust and they were pretty darned sweet. I'm thinking a smaller version for screwdrivers etc.
http://www.turnrobust.com/product/tool-h...le-system/
Doug
ShopDad
You will have to make 3 centers into both sides of the wood in equal distance. You do the first center on both sides then go to the next one on both sides and so on.
Same thing with 4, 6, or 8 sides on a handle.
Arlin
As of this time I am not teaching vets to turn. Also please do not send any items to me without prior notification. Thank You Everyone.
It is always the right time, to do the right thing.
Posts: 21,259
Threads: 2
Joined: Mar 2009
Location: IA
Allan
Would the difference be because of the high oils in Cocobolo then Ebony or maybe even how high oils in Lignum vite?
Or would the oil allow it to give alittle bit more then Ebony?
Arlin
As of this time I am not teaching vets to turn. Also please do not send any items to me without prior notification. Thank You Everyone.
It is always the right time, to do the right thing.
Posts: 10,742
Threads: 1
Joined: Jan 2006
Location: Orlando, Florida
I don't think the oil matters much. Would be an interesting experiment, though.
Arlin Eastman said:
Allan
Would the difference be because of the high oils in Cocobolo then Ebony or maybe even how high oils in Lignum vite?
Or would the oil allow it to give alittle bit more then Ebony?
Arlin
Still Learning,
Allan Hill
Posts: 20,950
Threads: 0
Joined: May 2005
AHill said:
I went and pulled several species from the wood database and compared density to both Janka Hardness and Crushing Strength. Both hardness and crushing strength are proportional to density - the higher the density, the harder the wood and the harder it is to compress the wood. There's some irregularity around the 0.55 to 0.60 density range, but the trend is about a straight a line as can be drawn from the data. In my case, cocobolo has an even higher density than ebony, and it's very hard. What I have learned from this discussion and my research is that I am better off either kerfing the tenon or grinding off the wings and using epoxy to set the shafts, or both. Both are acceptable methods, since they both achieve the same results.
And one is easily reversed/replaced. Think of a collet, that's what you're building with a kerfed tang. If you want to leave the wings on the driver shaft, you should bore two small holes where the wings will fit prior to boring the shaft hole. Even if the wood is friendly, it beats driving, and risking the blade, or trying to scrape with dental picks.
Better to follow the leader than the pack. Less to step in.
Posts: 4,912
Threads: 3
Joined: Apr 2009
bump to keep this alive
Currently a smarta$$ but hoping to one day graduate to wisea$$
Posts: 5,657
Threads: 0
Joined: May 2005
Location: Centre County Pennsylvania
Posts: 24,158
Threads: 2
Joined: Sep 2003
Location: Missouri
I use the Rockler kits.
Steve
Mo.
I miss the days of using my dinghy with a girlfriend too. Zack Butler-4/18/24
The Revos apparently are designed to clamp railroad ties and pull together horrifically prepared joints
WaterlooMark 02/9/2020
Posts: 116,481
Threads: 0
Joined: Jun 2002
Location: Sparkling Clearwater, Fl. Tampa Bay Area
(12-04-2016, 02:20 AM)Stwood_ Wrote:
I use the Rockler kits.
![[Image: tn_done002.jpg]](http://i8.photobucket.com/albums/a4/stwood/Screwdriver%20Kit/tn_done002.jpg)
.................................LIL
I have a metal lathe three jaw chuck which fits my Jet wood lathe..I grind the wings off a screwdriver shank and then grind two "flats" on it where it inserts into the wood. This prevents any slipping..Next I drill the correct size hole in the wood I am using for the handle, then I epoxy the shank into the handle...After the epoxy cures, I just chuck the shank up in the Jet, set the live center, turn the tenon for the ferrule and then turn the handle to whatever shape I want.The three jaw metal lathe chuck makes it easy and it always runs true to center..The Universal 3 jaw metal lathe chuck is one of the handiest accessories I have for my wood lathes...And you can snag them pretty inexpensively on Ebay...If they don't have the correct size threads, you can usually buy bushings to adapt them to your headstock. But always make sure before bidding.
Often Tested. Always Faithful. Brothers Forever
Jack Edgar, Sgt. U.S. Marines, Korea, America's Forgotten War
Get off my lawn !
Posts: 9,684
Threads: 0
Joined: May 2003
I use the Rockler kits also. Here are a bunch of mine. As you can see the possibilities are endless. Feel free to copy any of my designs.
Jim