CNC work - I want to make a Longworth chuck (for lathe) and have someone do the CNC

[Henry W]

I am looking to make a Longworth chuck like the one in the link below

https://www.woodturnerscatalog.com/p/103/4604/RMWoodCo-Modern-Longworth-Chuck?term=longworth

I have tried with plywood, and it works OK, but not smoothly.

I am wondering whether anyone with a 16" CNC can quote me a price for milling the arcs in two plates. These are (will be?) 1/4" phenolic plates, and the two plates have identical arcs - can likely be milled simultaneously (what I did with a router, no idea what depth a CNC can do).

The link shows a 16" version at $200. I am hoping to keep my total cost less than this - else I may as well buy the one listed. I will have the hardware costs to also consider.

Initially I would prefer ballpark costs so that I can figure IF it makes sense to proceed with a precise quote/cost. The layout is a small centering hole and the 8 arcs, as well as the 16" diameter circle.

Is this too much layout work for a one off?
Any takers?

Thanks for considering

I prefer e-mail - contact hwynands3 at yahoo.com

Henry

 

[tri4sale]

Are you providing the material?

Not sure how easily / nicely phenolic routes.

What size are the 8 arcs? Those would be the hardest thing (at least for me) to draw in the design software. The 16" circle and centering hole simple as can be to draw

With CNC best to route each separate, one after the other, and not to route one plate on top of the other plate.

 

[tri4sale]

12 inch version from a CNC site I belong to.

 

[Charlie]

Use MDF

 

[srhardwoods]

I'll draw it up in Aspire and post a model of it

 

[srhardwoods]

Here is quick and dirty, not sure what the center cut is supposed to be

 

[Charlie]

Here are just a few of the many sites for construction of a Longworth Chuck.

http://www.woodworkersguide.com/2010/10/17/how-to-make-a-longworth-chuck/

http://www.woodworkersjournal.com/bowl-turning-longworth-chuck-routing-pattern-cnc-files/

http://www.tnvalleywoodclub.org/articles/PDFs/Construction of a Longworth Chuck.pdf

http://blog.woodcraft.com/2012/04/how-to-make-a-longworth-chuck-with-ron-thompson/

 

[Obxwoody]

Chris you're getting good!

 

[ehpoole]

Are you providing the material?

Not sure how easily / nicely phenolic routes.

What size are the 8 arcs? Those would be the hardest thing (at least for me) to draw in the design software. The 16" circle and centering hole simple as can be to draw

With CNC best to route each separate, one after the other, and not to route one plate on top of the other plate.

Having routed phenolic before, it routes just fine if you take things a bit slower, but it is one of those materials that is very hard on cutters as it is often very abrasive. Also be aware that it can give off formaldehyde so you will want good ventilation during milling.

 

[Stuart Kent]

not sure if is helpful here because I don't work with phenolic, but I use compression bits for routing melamine with much better bit life and cut quality than spiral or straight fluted bits.

 

[Henry W]

My apologies for not following up on my post. Variety of reasons - I just don't have a lot of time to devote right now is the reality.
I appreciate the links and responses. I will follow up with those who contacted me about fabrication, but it will be in January.

Henry

 

[Michael Mathews]

Use MDF

Charlie, is that what you used? I saw yours, did you make it? How did you mill the slots? I, and Sam, would like to make one. I'm thinking a router with a circle/radius jig. and are both discs identical? just one reversed?

 

[Charlie]

Yes, I used 3/4" MDF, but 1/2" would be fine. I used a plunge router with a circle jig. Drill a center hole in each disc for alignment. Cut both discs at the same time and then reverse one. Plan on doing the routing outside on a nice day and wear a dust mask. Lol.

 

[allisnut]

How do you figure the center points for each arc?

 

[Charlie]

Check out the web sites I listed in post # 7. Lots of details.

 

[tri4sale]

Charlie, is that what you used? I saw yours, did you make it? How did you mill the slots? I, and Sam, would like to make one. I'm thinking a router with a circle/radius jig. and are both discs identical? just one reversed?

I'm thinking of making this with my CNC out of MDF. If it works it'll be easy to knock em out. At least the DC will get 99% of the dust it makes, as long as I remember to turn it on! Forgot to a few days ago, man the MDF dust was horrible!