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I spent a day or so tuning my sander and I did some top plates.

Only on You Tube can you see a grown man show off his wobble.

Thanks for showing that Chris. That was a good demostration of those techniques. It will be interesting to hear what others think.

John

Nice Job, Thanks Chris. An interesting combination of two principles. With the wobble principle are you primarily shaving until the volume is at an optimal level or the whole board is to a certain pitch? Also the weight you use you stated a couple of weights, I think 5lbs 5 oz then 5lbs 4.4oz, is it the later? Apologies if these are simple questions that I've missed the point on, the older I get the more frequently it happens these days

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Nick Oliver

http://www.oliver-guitars.com

Sorry about that Nick. The weight it 5lb. 4.4oz. I did stammer there a bit and the board should be 18" across grain laying on an 18" span. The weight is laid across grain. I have to make a new weight as the 3/4" PVC tube has lead shots in it but the conduit was too small and I went to buy some end caps to make another one from a piece of 1" I had but when getting back from Lowes the 1" was a 3/4" so I put a piece of strut with it. As far as the sound of the wobble I wasn't concerned with the pitch but more or less the volume or responsiveness of the top to make that musical like tone. But I'm also concerned with not getting too thin with the top. This is new to me and this is the first time I've tried it and I'm feeling my way around with it. But .100" seems too me to be the limit that I want to go with the top thickness. I kind of want to keep it as thick as I can. It just seems to me that a thicker top with lighter braces would be better then a thinner top with heavy braces. But I could be wrong and maybe someone with more experiance will chime in . At least from the structual point. I'd hate to bump the top and it just split because it's so thin and I'd hate to see the braces telegraphing through the finished top.

Hi Chris,

Thanks for putting your video tutorials together. They keep getting better with each one you do and I think it is fantastic that you are so willing to share what you have learned for everyone's benefit. Gotta love this OLF!

I am intrigued with the concept of deflection testing and Chladni patterns (some day I may understand it well enough to venture down the Chladni road). From your research and or hands on experience is there a specific reason for 5lbs 4.4 oz.? Intuitively, I could see where a different weight would be necessary for different species to produce the same degree of deflection. How is it that you came up with that specific weight?

Cheers and please, keep the tutes coming.

Rick Cowan

Oh, BTW I have serious workshop envy! You have a great setup!

Chris : Nice job as usual. Have a few observations and please don't take any of this to be critical but rather it's meant to be constructive. Understand the 18 " width for deflection testing.Standard size ,relevent measurements.To me it looked like you were very close to.250 at the .108 measurement. Was surprised to see you take .008 more off the plate.Think it would be interesting to use a dial indicator and see what is the actual deflection.
Don't know what the width of your guitar is going to,but would seem to me that when the plate is taken to correct size there would be less of the sheet metal like "wobble".Less weight and less leverage.
Chris,this certainly looks interesting,all my guitars to date have been by flexing in the hand and seat of the pants feel.Hope somemore folks chime in. Thanks Again,Tom.

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The video seems to be removed?

Kind regards,


Edzard

Chris nice video. A couple of suggestions. How about a 5lb dumb bell? They are pretty cheap at K-Mart, Walmart or similar stores. Also instead of a 1/4" piece of wood to measure deflection I think a dial indicator would be much more reliable.

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I've edited it and will post the edited version once up.
It should be up now.

Very nice video. That is really helpful!

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Eddie Lee

Great Video Chris! It sure is helpful to see and hear this process. Thanks for sharing. Dennis

Bob, wanted to have the weight be able to span the 18" of width of the plates so it would be evenly distributed across the plate. Even with crude lead shot filled pvc conduit and unistrut ( can you guess I'm an electrician by day) weight I had to shift it some so the weight wasn't to one side too much. I think the dumb bell (and I don't mean me) would have put the weight at the center and not across it. Actually I could have put the plate on two 1/4" dowels and when it hit the table there you go. Like I said if not here then on another forum the 1/4" is a starting point or minimum. Although I agree with you and will probably get a dial indicator and make a real test gage and start measuring my defection and weights(just bought a digital scale from HF) not only in tops and backs but braces also and start recording data so I have something to refer to in the future. I know I've been slacking in this department. Why do think I YouTube this stuff? So I have something to look at to remember how I did it in the first place.