How to turn to a drawing *LINK*

Re: How to turn to a drawing

Ed Davidson

That reminds me of my very first experience on a wood lathe...8th grade shop class in north Dallas back in 1965. I had to come up with a dimensioned drawing for the 6" diameter maple and walnut bowl I was charged with making. The finished piece looked pretty good to me, but the teacher gave me a C-, as the finished piece measured 5.25", and not the specified 6". It must have left quite an impression...haven't worked off a dimensioned drawing since :-)

Re: How to turn to a drawing

john lucas

Brian is a good turner and friend. I met he and his dad simply because I was in Atlanta and decided to look up AAW members in the Atlanta area and simply called one to see. It was Brian's dad Hal and they didn't live far away so went to visit. Had a great time and have watched Brian's career take off after that.

I did a demo at one symposium on duplicating turnings. I do a lot of duplicate turnings for locals who need repairs of antique furniture. It was the worst attended demo I've ever done. apparently people simply aren't interested in learning to turn more than one of something.

Most of the time simple measurements are enough. Sometimes you need a template that you can lay over the piece to really nail the smaller curved shapes. The latest technique started by the shift to video hollowing and pushed by Alan Zenriech is to use a video overlay of the shape you need and you just turn to match the video image. Pretty cool and dead on. Maybe I can get Alan to post his video of this technique.

Re: How to turn to a drawing

lyle Jamieson

I will often start my students out with a drawing of the intended shape before we start turning. This is often very revealing to the students skill level. If they start with a drawing with a concave element and it is turned into a convex shape the desire does not match the skill level. It can be very frustrating when the mind/drawing wants one thing and the body/ tool control ends up with something else. I think that is where the "Go with the flow" attitude comes from. It is easier to "let the wood speak to me", rather then learn how to turn. For me it is a control thing. Who is in control the wood or the turner??

Re: How to turn to a drawing

mikeee12345

It is that Zen moment of Yin and Yang, when the wood turner and the wood billet

come together in perfect harmony......and then you wake up with a concussion realizing

the bowl blank came off the lathe and knocked you senseless. :-)

Re: How to turn to a drawing

Alan Zenreich

One approach is to use a video camera above the lathe and superimpose a graphic of the shape you want.

Take a look at the 2:30 point in this video. https://www.youtube.com/watch?v=0kYF3fgwhBs

A few years ago, Lauren photographed an egg from our refrigerator, and then not only was able to turn an egg shape, but THAT specific egg shape.

General spindle turning/duplicating has some issues to deal with, but you might find the technique useful.

These days, I suggest using a computer and webcam instead of a phone for overlaying the static graphic on the live image, but you might get the idea.

Re: How to turn to a drawing

David Walser

Alan -- Thank you for the suggestion and for the link. It's good information.

What I found interesting about the video that I linked to was that is supplied information that many self-taught turners lack. My school district eliminated shop classes (and home economics) the year before I would have been required to take shop. So, I never had the benefit of turning a table leg in 9th grade wood shop and didn't learn the process of turning to a drawing.

Years later, I took a 5-day introductory turning class from Dale Nish. He taught how to make all the various cuts and he used projects to reinforce that learning. But, he never taught the process of turning to a drawing. In the 15+ years since I took that class, I have learned on my own how to turn to a drawing. (That skill became critical the first time I turned a segmented vessel. If my outside curve didn't follow the drawing, I could have easily blown through the side of the vessel.) Over time, I developed a process that is surprisingly similar to the one shown in the video.

Using a video overlay (or turning to a shadow cast by a light above the turning onto the drawing mounted on the lathe bed) makes it fairly easy to turn to an exact shape. But, it doesn't help with knowing where to start taking away the wood. To many of you, that may sound obvious, but I found it daunting at first.

duplicating turnings

john lucas

Well I didn't have to go from a drawing. My customer brought me 2 finials. Both just a little different. He needed 6. these aren't exact duplicates because the price we decided on dictated that. The spindles will be 12 feet in the air and 6 feet apart so for all practical purposes they are identical.

Here are the tools I have laid out to get all the dimensions accurate. The only wood I could get was just a hair too small so I subtracted 8% from all the dimensions. Unless you measure you will never be able to tell I did that. Here is one of the finials he left me. All the tools are labeled by number and a written description of the steps I planned to turn matches those numbers. So I just look at step #1 and then pick up the # 1 measuring tools. Outside calipers for the dimensions. Pointed calipers for the spacing.

Here is a photo of one of them just before I started sanding. We have been having a discussion on another website about what grind I use and whether or not a finer grind leaves a better finish. This was done mostly with my Thompson 1/2" spindle gouge ground on a 180 grit CBN wheel and then honed using a 600 grit diamond hone. I think the finish speaks for itself. I just touched them up with 180 grit. He is going to paint them so I could have just left them alone but I wanted them all to look really finished when i handed them over to him and the sandpaper evens out the appearance.

Re: duplicating turnings

Don Orr

Very nice John-thanks for sharing your technique and insights.

Re: duplicating turnings

Don Stephan

I'm not seeing obvious glue lines of laminations. Would you remember the wood used, and where you found it in that thickness?

Re: duplicating turnings

John C Lucas

It was a pine 4x4 from Lowes. I thought about laminating but this board only cost $7.

Re: How to turn to a drawing