Tuesday, October 25, 2011

A foot in the door.


I had an idea a couple of nights ago and had to try it out. This was the first opportunity to give it a shot. I started by cutting a piece of Birdseye maple from the veneer log core I got a couple weeks ago. It's only 6" diameter so I was very limited in size but the quality of the wood made up for the lack of size. The piece was ripped in half to give me 2 blanks 6" diameter, 6 1/2" long, and 3" deep.












I marked the center on both sides and mounted it between centers. The drive center is a 1" diameter Woodriver multi tooth drive center (stebcenter). The live center the Jet live center that came with my lathe.  It's nearly identical to the Oneway live center.













The outside shaped and a tenon turned so the inside can be hollowed. I have not sanded yet, the finish is straight off the gouge. I love the look of the Birdseye, unfortunately it doesn't show up very well on what will become the rim or on the end grain.












The bowl was flipped around and mounted in the chuck.  The rim was shaped, and the center is now ready to be hollowed out. The blank wasn't quite big enough to core, and even if it was a little bigger the Birdseye is much less pronounced as the diameter gets smaller.











After hollowing the inside of the bowl was sanded before flipped around again and mounted on my vacuum chuck. The tenon was removed, a small recess turned, and the outside sanded smooth. The vacuum drum I'm using here is a 3" PVC pipe coupler.












The inside of the finished bowl. The rim is under cut significantly so it's not as heavy as it appears. The under cut rim made sanding difficult so the interior isn't as smooth as I would like. Such is life.













Bottom view, this is where my idea came to fruition. Turning the collar for my recent hollow form gave me the idea that I could do the same thing for a foot. I followed the same process as I did for the collar, except instead of fitting it for the opening in the hollow form I fit it for the recess I turned in the bottom. The wood for the ring is Desert Ironwood.









Profile view. The foot gives it lift, the color gives it contrast, and it's a nice surprise for the buyer when they flip it over to see the extra effort put into making the piece special.










Here's my sketch from this evening, before I headed out to the shop.  The shape is different on the outside than what I had drawn but the overall effect is exactly what I had envisioned when I thought of using the collar as a foot. 

Monday, October 24, 2011

Twisted box how-to

Laying out and numbering the centers for a 3 sided multi-axis pieces with a 120 degree twist.  The 2 diagrams represent opposite ends of the same blank.  Find and mark the center of each end of the blank.  Draw a line diagonally from corner to corner on each end of the blank.  This line should pass through the center mark and should be parallel on both ends.  This line is crucial as it will give us 1 of our 3 centerpoints and will give us an intermediate point that will allow us to find the other 2 points easily.  Using a compass draw a circle using the true center point as the pivot point.  For a 3" square blank I use a 1" diameter circle (1/2" radius).  Using a larger circle is possible but it will result in a slightly different shape (flatter sides) but will make it easier for the center points to be turned off by accident.  I always make the circles the same size on both ends.  I also do all of the layout and numbering before any cuts have been made. 
The diagonal line will intersect the circle at 2 points, once in the upper left, and again in the lower right.  When doing a lidded box I always number the top first and always number the point where the line intersects the circle in the upper left as point #1.  The intersection in the lower right will be used to find points 2 and 3.  Using a compass set to the radius as the original circle, place the pivot point on the intermediate point in the lower right corner.  Draw an arc that intersects the circle at 2 points and also passes through the original center point.  The 2 points where this new arc intersects the circle are the other 2 points that we need.

If we've done the layout correctly we should have 3 points on each end that are properly aligned to one another and are 120 degrees apart.  The next step is numbering the blank.  I always number the blanks in the same order and using the same method.  The top side is always side A and is always numbered first.

The intersection of the circle and the diagonal line in the upper left hand corner (opposite the intermediate point used to find points 2 and 3) is always labeled as point #1.  The remaining points on Side A are then always labeled going clockwise from point #1. I always number the points to the insde (interior) of the blank.  Numbering on the outside increases the chances that the numbers will be turned off.  This is an issue that can be overcame if it happens but it is easily avoidable by simply numbering on the inside of the circle.  

The layout for Side B can then be completed.  Point 1 should not be parallel to point 1 on Side A.  The other 2 points are then numbered going in a counterclockwise direction.  The direction of the twist can be controlled by putting point 1 opposite point 2 or opposite point 3 (I never taken the time to figure out which direction is which). 

After the layout is complete I start the turnin process.  Step 1 is to mount the blank between the true center points and turn a tenon on each end.  The lid portion can then be parted off (or cut off on a bandsaw, another reason to leave the blank square) and both halves hollowed, a tenon and recess formed to join the lid and body.  To turn the twisted exterior it's simply a matter of lining up point 1 on Side A with point 1 on Side B and turn that face.  Then line up points 2 and 2 and turn the face, and then points 3 and 3 and turn that face.  I usually end up turning each face 3 or 4 times to get the wall thickness I want and to get all the faces even.

Sunday, October 23, 2011

QS Ash HF


I didn't know what I wanted to work on tonight and I'm not sure why I chose to work on this piece but I did. This is a chunk of quartersawn curly Ash I got from Mike Mahoney back in July. It sat in my shop for about a month and a half before I roughed it out. It was the bagged for another month and a half leading up to tonight (http://agoodturndaily.blogspot.com/2011/09/sleepy-hollow.html)





Because it had been roughed to about 1/2" thick there wasn't much material left to remove to get it down to final thickness. The piece had warped slightly so it was trued up on the outside before I setup my hollowing rig. Hollowing was done without a laser and because the piece doesn't have any voids determining wall thickness is based mainly on experience and sound. The pitch goes up as the piece gets thinner. Learning to judge the wall thickness by the increasing pitch is something that can only be learned through experience.



Top view. The hole could be slightly smaller and the final weight could be slightly lighter if the bottom was a little thinner but overall I'm pretty happy. It's a relatively plain piece of wood and the simple but elegant form really accentuates the grain and the curl. I don't do much with quartersawn wood and I don't do much with Ash so this was all new to me.

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Monday, October 17, 2011

Election day

Saturday was our club election for the 2012 officers. We normally do nominations in October and the election in November but because of an all day demo next month we had to do the nominations and election on the same day. We have 4 elected positions: president, vice president, treasurer, and secretary. I've been vice president for the past 3 years and have been planning to run for president for the past 6 months or so. Because our current president is dealing with some health issues I've been running the club for the last 3 months, this month that meant not only presiding over the meeting but also dealing with the nomination process, the balloting, and the election results.

After the nomination process I was the only nominee for president, there were 2 nominees for vice president and for treasurer, and 1 nominee for secretary.

As I was running unopposed and it was well known that was actively seeking the position it wasn't surprising when the results were announced. I was unanimously elected president for 2012. I think we have a very strong set of officers for 2012 and I look forward to working with them to improve the club.


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Yea or Nay?

 I talked to a few club members on Saturday about my latest hollow form.  Consensus was that an Ebony or African Blackwood collar would probably highlight the black line spalting better than the Desert Ironwood collar I originally had in place.  With that in mind I headed out to the shop last night to give it a go.  Here a blank approximately 2" square and 3/8" thick is secured between the live center and the front face of the spindle.  This is a trick I picked up from Mark St. Leger back in 2009.  There's plenty of friction to drive the blank and the flat face of the spindle ensures that the blank is square to the lathe.
 The blank is turned round and a tenon is formed that matches the diameter of the opening that it is to fit.  Using this method the blank can usually be removed from the lathe for test fittings and be placed back with a high degree of accuracy.  I also faced off the bottom of the tenon and under cut the shoulder on the tenon so the area near the tenon doesn't bottom out before the outer rim does.  I use a 1/2" bowl gouge to turn it round, and a 3/8" diamond shaped parting tool and 3/8" spindle gouge to shape the tenon.
 I also took the time to shape part of the upper profile and to start to contour the under side of the tenon.  I won't have access to it any other time and when people try to feel the inside of the vessel (and they will, other turners in particular) I don't want them to feel a sharp corner.  I also prefer the depth of the tenon to match the thickness of the vessel at the opening.

A quick sketch illustrating the cross section of the finished collar.  The tenon matches the thickness of the wall and the under side of the tenon is contoured so the transition is as seamless as possible.  I like to get the cross section as close to round as possible and there should not be a gap between the vessel and the collar at any point.  The collar should look like it belongs on the piece and was not an after thought.
To turn the top and inside of the collar I use a shop made jig based on a jig used by Mark St. Leger.  It's scrap end grain maple.  A groove is cut on one side to allow the wood to expand and contract as the jaws of the chuck are opened and closed.  The face of the jig is turned flat and a recess is turned in the face so that the tenon of the collar fits inside snugly.  The recess should be deeper than the length of the tenon so to outside lip of the collar rests on the face of the jig.  The jaws of the chuck are then snugged tight and the collar is held securely by the jig, not the jaws of the chuck.
The collar is placed in the jig so the top and inside of the collar can be turned.  You can see ring where the end of the spindle compressed the wax sealant on the outside of the blank.  If you look carefully and compare with the photo above you can see how the gap in the is narrower in this photo, the wood is flexible enough to move and compress as the jaws are tightened.
And now the face and inside of the collar have been turned and sanded.  The back side of the ring is relieved and the contour matched to give me the cross section I want.  The collar can be removed, test fit, and then placed back in the chuck for any additional turning with very good accuracy.  All of this shaping work is done with a 3/8" spindle gouge with a fingernail grind.
The finished rings side by side.  Desert Ironwood on the left and Ebony on the right.  The light ring on the Ebony is light reflecting off the highly polished surface.  The color of the collar is almost pure jet black, unless you look closely for the grain some might assume it's plastic, not wood.  One strike against the Ebony.
The Ebony collar set in place.  I think the black color brings out the black line spalting in the piece.






The original Desert Ironwood collar.  I think the Desert Ironwood looks more natural (less like plastic) but it doesn't work as well with the spalt lines.  I do prefer the shape of this collar better, the one above is a little flat so if I decide to go with the Ebony I will probably turn a new one anyway.

Should I go with the Ebony or with the Desert Ironwood?

Friday, October 14, 2011

Playing favorites



I know I'm usually pretty happy after finishing a piece, in this case I'm ecstatic. This is quite possibly the best piece I've ever done. Not only is the wood gorgeous but the quality of the turning is very nearly as perfect as I can do. Having a gorgeous piece of wood like this certainly helps but the best piece of wood in the world doesn't do you any good if you butcher it in the process.






The collar is a small piece of Desert Ironwood burl. I wanted to dress up the edge and use a contrasting color. The collar isn't permanently attached yet so I may make one out of Ebony and a few other woods to see which I like best.








If I'm being really picky I can pick out a few small flaws and things I would change (mostly on the inside) but overall I am thrilled with how this ended up. I think I have a pretty good idea what is inside a piece before I start turning. In this case I am truly shocked at what I found in this blank.







Bottom view opposite the void. I suspect that the guy who sold me this blank will end up regretting it. He's also a turner and based on what I ended up with he let it go for way less than it's worth.










One more reminder of what I started with. This is upside down to what ended up being the final orientation.

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Thursday, October 13, 2011

Breakthrough


I worked on the spalted maple hollow form tonight. I didn't have much time so I didn't get as much done as I wanted but that's life. I did get about 1/2 of the hollowing done, including breaking open the void on the bottom/side. This is very helpful when this happens as I can now see and feel the wall thickness through the entire piece. Additionally the open void allows the chips to evacuate as I'm working. On a completely closed vessel the chips build up and can compact inside the piece. The lathe has to be stopped and the chips removed manually or by compressed air. An additional step I prefer not to have to do.







The bug holes will also allow me to better judge my wall thickness. I'm leaning towards putting a simple collar around the opening to dress it up a bit but I'm also open to making a pedestal/lid/finial combination to really push it over the top.

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Wednesday, October 12, 2011

A bird in the hand


More work on the Birdseye hollow form tonight. Several small chunks broke out around the crack on the end grain near the shoulder. To prevent the crack from opening wider I wrapped the shoulder with painters tape.














The side opposite of the crack. I think it's neat how you can see how the eyes radiate out from the center on the end grain. They're clearly smaller near the center and grow larger toward the larger diameter.














Unfortunately the center was quite rotten and was torn out. As a result I was unable to finish sanding the bottom. I'm thinking about possibly adding a pedestal and finial to this piece to dress it up and to hide the hole in the bottom.















Profile view. This is the best view of the Birdseye figure and the best representation of the overall shape of this piece. It's a little heavier than I'd like and I'm not quite sure why. It's not overly thick in any area (easily checked because of the crack) I suspect the wood is just denser than it looks.

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Tuesday, October 11, 2011

Scratching the surface



This is one of the other pieces I purchased Sunday night. It had several bark inclusions which I broke loose before starting.










I had high hopes that the black coloring was more than just superficial. To that end I planned to turn a hollow form in this orientation, with the black color and the voids on the top.










This is what I planned to be the bottom. The piece started at 9" diameter and 4.5" thick. I was told it is elm but I now suspect it's maple.









This is a section of the Birdseye Maple veneer boule. Even in a dirty and rough state the intense Birdseye figure is clearly visible.
















And here's the crack running down the side. It's unfortunate that this defect is present but that's what happens when green wood dries too fast.














On the end you can see where the drive centers from the veneer lathe gripped the log as the veneer was being cut. I normally use a 1" diameter drive center. The veneer lathe used one at least 6" diameter.
















The remainder of the veneer boule. 6" diameter and just under 6' long.
















I roughed out the outside of both pieces and then started hollowing with a small scraper. The piece on the right is the piece I hoped would have all the black coloring. That coloring ended up being only on the surface. After seeing the coloring and the spalting patterns I decided to flip the orientation of the blank.








The large void will now be on the bottom and the the lighter color and bug holes on the top.











Profile view of both pieces. I was afraid that I would be disappointed with the blank without the black coloring. In some ways I think that this coloring is better.











Close up view of the Birdseye figure. This stuff is very intense, I can't wait to get it finished.

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Monday, October 10, 2011

Wild weekend


Saturday evening was biannual Sunnyslope Art Walk. This was my display. Sales were small and slow but constant and at the end of the night added up to a half decent total. I also got a couple of leads to get my work in some shops and to participate in other shows.









I finished and assembled my peppermill Sunday morning. The oil finish really made the color pop. I still have a few pieces of this wood left but I wish I had more.














Here's the bottom view There are 3 parts visible here (plus 2 screws). The adjustment knob that normally goes on the top of the mill is the darker circle in the center. Both parts of the grinding mechanism are the 2 larger circles. The screws don't secure the mechanism, they only prevent the outside part of the mechanism from rotating while in use.












This is the drive shaft. It's secured upside down to the bottom of the knob. The drive plate goes over the square shaft, the end of the shaft is mushroomed over so it is held in place under the drive plate. This also means that I was able to get a 10.5" tall mill out of a 7" kit.













Sunday night I met another turner that had some wood for sale. Among the pile was this piece of Birdseye Maple. It's about 6" diameter and 6' long. It is the center out of a veneer log. It has a huge crack down one side. I'll have to deal with that once I decide what to do with it. For now I'll just stare at it and think of the possibilities.

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