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So I did some googling on how to make a radius block. Turns out a large rotating cutter traces a radius when tilted. It's not 100% accurate but for some wood item, it's plenty accurate (it may be off by a couple of microns, that's all). There is a formula out there that tells you how much to tilt the spindle vs. the radius of the cutter and the radius you're trying to achieve.



This is my setup





This is the end result:

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Well done, Tai - this old tool and die maker approves!

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"Act your age, not your shoe size" - Prince

I wish my neighbor does... he kinda dislikes manual machinists and thinks they're all inefficient and useless... he has this:





I showed him what I made and he doesn't seem impressed at all and thinks his machines can make it in seconds... (I guess not counting all the time to CAD and CAM all the various radii

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Clever!

Well Done Tai. Don't worry about the neighbor, he is just jealous

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Joe Beaver
Maker of Sawdust

You can do the same thing on your table saw in wood, and maybe even aluminum (I'm not sure). Just google "table saw cove"

Ed

I've been a machinist for over 40 years, starting before CNC on lathes making replacement parts for presses. Making large adjusting screws, re-threading the pitmans they fit into, backshafts, crankshafts, all on conventional lathes. Not even digital readouts. I did that all with 0-5 years experience. Changed to CNC 30 years ago.

Sometimes conventional is by far the easiest and fastest way to do things. Many times I'll use a CNC mill like a Bridgeport, and do some simple task in far less time than programming it. The kids won't do it though. They know more than I'll ever forget. They have a 4 year program, and school. Times have changed.

I think that the shape that you got would properly be called an ellipse because of the tilt of the head, but it is close enough to a radius until you get wider. Well done. I like the way you just get in and do it.

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Why be normal?

Yea, I don't have a table saw... I'm not even sure if I have space for one. I like to have one though since I can just make my own kerfed lining from construction wood rather than buy it.

The only thing a table saw won't do is if I want to make a radius block out of a piece of chrome moly steel, I don't think table saw will do it. I would absolutely not do this with aluminum on a table saw either... a table saw isn't made to cut aluminum in the first place and it's dangerous to try to cut it across.

On the other hand, I can cut chrome moly steel or even hardened steel if I want to... not sure why I want to however. That carbide insert can cut almost anything.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Except a CNC mill doesn't like being used like a bridgeport, at least according to my neighbor. He says you don't really have the same feel and it's very easy to make mistakes. You also don't want to manual power tap on a CNC either without a specific program for that thread and pitch (though you could just enter the right G code on the computer and hit the green button)

By the way I also need to make some coves to use as a neck rest out of some construction wood. I could buy it but then I'd have to pay shipping for it.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Yes, they have no feel, but they have the same sound. I run the machines by the way that they sound, especially lathes, the machines I have the most experience with. I couldn't tap manually on a CNC, but milling off stock, bringing to length, and drilling holes you can do all day long. If you need .200" off a plate, you can take .180 off quickly on a mill by hand, and grind the last .02 off.

By the way; I DO cut hardened steel. M2, and many kinds of die steel from 45-65 Rc. Sometimes with carbide, especially long small bore that are prone to chatter, (but you have to go slow, and it wears quickly) but mostly with ceramic inserts, or CBN if it is an interrupted cut, or has a very hard coating on it.

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Why be normal?

Tia

I have cut aluminum on a table saw and a band saw no problem - I am unfamiliar with cutting from the side of the blade as you would in making a cove. Even Home Cheapo and Blowes have aluminum cutting blades for your table saw and hand-held circular saw.

I think the kerf width of a tables saw is too wide for kerfed lining - a bandsaw blade's width seems to be about right. And jigs are very easy to make.

ED

Very cool indeed. You may even find a market for such a thing.