Turning curly wood questions
I was making a small handle for a cheese knife and happened across a piece of curly yellow birch in the wood pile so I figured I would use it. This is the first time that I've tried turning anything like it. Is there any secrets or tips to turning it? Almost everything I tried would leave the turning not smooth. The figure in the wood was raised. I tried taking a picture but it was too hard to see.
When I tried my skew it would work ok but on two occasions it pulled a chunk of the wood out, not like it caught an edge it just came out. That could of been due to unseen checking in the wood. Since it was in the wood pile it was't properly dried for turning. I tried turning at all different speeds. In the end I was able to get it smooth by using my Ellsworth grind bowl gouge using one of the wings a lot further up than I've ever had to. By using the bevel I was able to take the thinnest of shavings and it worked. Is there a better technique? This piece of wood didn't look like it was close to the stump so maybe the whole tree was naturally curly. I'm trying to focus on using the lathe tools over sanding to finish projects. I don't know if it makes a difference but I turned it at a slight angle so the curl shows up at an angle on the handle.
I'm at work but if needed I can take a couple pics tonight. I often encounter maple (usually red but sometimes sugar) that's curly so I'd like to learn more.
3 Attachment(s)
skew, sharp, and tool rests
This is the type of hone I like the best, EZE-Lap, easy to hold firmly against both the heel and the edge (to prevent rounding over) by putting the forefinger right over the diamond plate. I use the blue extra fine the most. They are not real cheap but last for years.
Attachment 400990
That said, for touching up skews (and other tools) I've gone to a different method between honings. I resaw a piece of MDF about 5-6" long to expose a rougher surface then rub polishing compound on that surface. I've tried the Tormek honing compound and various stick polishing compounds and they all work. To use, hold the skew flat on the surface, the bevel tight between the heel and the edge, lift the heel just barely from the surface, and draw the skew down the board while applying some pressure. You can see that it's working by the black streaks left on the board. This takes off much less metal than the diamond hone and makes a polished razor-sharp edge.
I can't remember having surface where I could feel the figure, like ripples. I wonder if it's the way the skew is held. The grain in figured wood is in waves like on water with the fibers moving up and down along the length. If the edge of the skew is following the grain it might leave a ripple on the surface. If the angle of the edge is too steep, i.e., the skew handle is swung so the edge is closer to vertical than horizontal, it might tend to follow the grain more. If so, you might try planing with the handle swung the other way so the edge is more towards the horizontal. That can result in a flatter surface since a longer portion of the edge is in contact, cutting a wider swath at once.
Another thing, don't try to achieve a fine cut with too much of the bevel rubbing against the wood. This will amplify any ripples with each pass. The only part of the bevel in contact will be right at the edge, less than 1/16". To keep the heel of the bevel out of the way I usually grind it off a little on skews (and more on spindle and bowl gouges. This is the grind Chris Ramsey uses for turning cowboy hats, ground freehand, no jig. I highlighted the actual bevel with red. (I don't grind my bevels nearly as much as he does, just a little.)
Attachment 400994
As for tool rests, I've thrown all my cast iron rests in a box and bought a set of Robust rests for each lathe. The top is a hardened 1/4" steel rod which never dents or scratches and the tools slide perfectly. The rests are shaped nicely to get the edge very close to the work where needed. I like the low profile versions for the shorter rests (I use the 4", 6", 9", and 14" plus bowl and box rests.)
Cast iron rests need to be constantly dressed and lubricated for the tools to slide properly - it's probably not you! They are usually pretty bad even when new. A flat file is the best for removing irregularities, followed by fine sandpaper (I glue sandpaper to a flat stick). When smooth, lubricate with something - I used Renaissance wax. The edge needs to be slick enough that the tool slides effortlessly. One guy who tool a class with the other John Jordan woodturner told me he had students dress the tool rest before they turned on the lathe the first time each day.
(BTW, one new cast iron rest that came with one of my lathes had porosity, holes on the sliding edge the tools caught on! I filled them with JB Weld and the rest was fine after dressing and lube)
Another possible thing - some inexpensive skews are poorly made with sharp corners down the shaft. These corners need to be rounded over and smoothed so they don't catch on small irregularities on the rest - you can do that with a diamond hone even on well-hardened steel. The Thompson skews (my favorite) are radiused down the short point edge. You might be able to see that in this picture (I ground the middle one into a negative rake scraper):
Attachment 400993
BTW, if you use a skew as a NRS it dulls the edge which needs to be resharpend/honed before using it as a skew again. In fact, NRS do not work very well without a proper burr. Best to grind a tool specifically as a negative rake scraper. (I use a carbide rod to burnish the burr rather than rely on the short-lived burr from the grinder that most use.)
Don't give up on the skew! Many experts say if you learn spindle turning first it will teach you the fine tool control that will let you turn anything. So many people start by turning bowls with green wood and sometimes never get past that - but face it, turning green is easy and a lot of fun but it's almost too easy and not much challenge.
If you find yourself in this area stop in for some skew play! When I teach beginners who had never even seen a lathe the first tool in their hands is a skew! (With the straight bevel it's actually the simplest tool in the kit) We learn the skew first, before even introducing the roughing gouge and the spindle gouge. So far none have failed to catch on quickly (and no one has ever had a catch!)
JKJ
Quote:
Originally Posted by
Alex Zeller
Yes, this was before sanding.
Both the skew and gouge were very sharp. I have my grinder on a side cart on a tool box that I roll right next to the lathe. It's literally out of the way but two steps from the lathe so I can touch up the tools and get back to turning in a minute or two. That being said I'm much better with the grinding wheel than honing so I may not be getting the tools as sharp as needed. I only have one skew and it's curved and I've only used it as a skew, not a negative edged scraper. I haven't done much spindle turning so I've only got bowl gouges and I didn't try the standard bowl gouge (I only use that to do the inside bottom of bowls).
Sounds like I need to step up my skills on honing. I have a limited selection of tools. The last tools I got were two carbine tools, a diamond one and the one that's a small circle with the outer edge that looks more like a skew than a scraper. While adding more tools is always an option (and fun) it sounds like it's more my skills than lack of the right tool.
One of the things I don't like about my Grizzly lathe is the tool rest seams like it's a cast piece of steel. When making gentle cuts it feels like I can't slide the tool on it smoothly. It could be my skill level and the rest is just fine. I've filed it down some to try to make it better. Not having the experience or even any time on another lathe (I was only able to get to one club meeting and even then it was too late to do much more than meet people) I'm wondering if that would be a much better upgrade.
