Tell me about vacuum chucks and chucks

[William C Rogers]

I'm still way below the skill and artistic levels I have seen here, but I feel I'm improving. I have bought some Thompson tools and appreciate the quality. I'm satisfied with my PM 90 lathe ( now with 18" swing ). So now I am wondering how beneficial a vacuum chuck would be? My current chucks are both PSI Barracuda. One is a 2 and the other is a 4. I know these are not the "recommended" chucks, but they have done everything I have asked. Are the other brands that much better? Or would it make more sense to invest in a vacuum chuck? Those that have them do you use them a lot of are they just an occasional use. Are they used for more than cleaning up the tendon on a bowl? I do have Cole jaws for both chucks. Funds are limited, so what would you recommend? Looking around at vacuum systems, the Frugal system seems to be the most economical.

[John Keeton]

What do you want or intend to turn? For some pieces, a vacuum chuck is very handy. For others, it has little benefit. I don't find mine all that useful for bowl bottoms, but for some speciality work, it is an absolute necessity.

[William C Rogers]

What do you want or intend to turn? For some pieces, a vacuum chuck is very handy. For others, it has little benefit. I don't find mine all that useful for bowl bottoms, but for some speciality work, it is an absolute necessity.

Thanks for the reply. Right now I'm turning bowls and small lidded boxes. I guess what I'm wondering is what capability do you get using a vacuum chuck. I eventually want to do some hollow form, but that takes some speciality tools I don't have at this time.

[Thom Sturgill]

The vacuum chuck is best for natural edged bowls, especially when the rim is not flat. Cole jaws, doughnut chucks, etc do not work well with these forms, though a jam chuck turned to fit tight against the inside works well with tailstock pressure. It is especially poor if the wood is porous. I would not use one as the primary chuck.

As to the Barracuda chucks, I started with them and launched several pieces regardless of how carefully I made the tenon. I switched to Nova chucks and have not launched anything from one. Our club turns tops (about 700) every year at the county fair. One year we had a selection of chucks for the three lathes, a barracuda, a super-nova2 and a OneWay. Both the Oneway and the Barracuda with their serrated jaws launched blanks by several different turners. The Nova did not.

Its not the chuck, its the jaws. I have dovetail jaws on my remaining Barracuda and it works fine.

[John Keeton]

I don't want to get into a "chuck debate", but I will agree with Thom on the dovetail jaws. I have used several different chucks, and prefer my Nova dovetail jaws.

I suppose there are work arounds for nearly any situation, but a vaccum chuck is handy. I use jam chucks a lot, and I would suggest to you that you wait until your work takes a direction where you need one. I have done a lot of hollow forms, but it is a rare situation with them where I use my vacuum setup. To finish the bottom of those, I use a conical jam in the opening with some friction to drive the piece and finish the bottom down to a removable nub. Rubber Chucky makes a device that works well for that.

[Kyle Iwamoto]

I agree with using a jam chuck. It's also FREE. Use scrap from your turning or anything. There's way better places to spend you money at this point. Coring tools is one of them. I think anyways. If you can core just 2 extra bowls from a blank, you'll pay form them in no time. If you sell your turnings, that is. If you don't sell, there are some nice woods out there that you just want to utilize to the fullest, instead of turning them into shavings.

[John K Jordan]

William,

I've been turning for about 15 years now and have done many bowls, platters, and other face turnings without a vacuum chuck. There were plenty of times where a vacuum chuck could have been used but so far my design or execution has not been limited by the lack of a vacuum chuck. A couple of months ago I finally bought a complete vacuum system and have not yet used it.

There are so many ways to hold even awkward things to finish the bottoms - cole, longworth, or other big jaws, home-made donut chuck, jam chucks, pressure chucks, duct tape, plywood with wooden clips held with screws, etc. One simple way is to simply support the object with the tailstock and turn the tenon down to a nub then finish with hand tools. (use some sort of jam or pressure from the headstock end)

Another of my favorite methods of cleaning up a tenon is don't use a tenon! Where appropriate I prefer to expand dovetail jaws into a recess. With a little thought the recess (or tenon) can be disguised as part of the bottom design:

bottom_IMG_4687.jpg

Also, you really don't need much of a recess to hold even a large platter if the radius is large, the wood is strong, you are careful with your technique, and use tailstock support as long as possible. This platter was over 18":

bottom_PC012804_e.jpg

(The multi-axis base idea is from Frank Penta.)

There is of course nothing wrong with falling into the bottomless pit of collecting tools (all guilty, raise your right hand with me) but if you can hold off buying you might run across a used vacuum chucking system. Since we all get older, great used tools will always be available!

JKJ

[William C Rogers]

Thanks for the replies. I'm now thinking I'm really not ready for a vacuum chuck. I still need to turn a lot more things first before expanding. Vacuum chucking seems more for speciality.
Thom, where did you get dovetail jaws for the Barracuda? I have both the Barracuda 2 and 4. I primarily use the 2 for cold jaws. PSI now has a 6 jaw chuck, but uses Tommy bars. Since I now have 18" swing, many a Nova chuck would be a better investment.
John, Rubber Chucky looks interesting.
Kyle, I do have an interest in coring. A club member recently bought a system and I need go talk to him about that.
JKJ, I have admired your work. I am going to do the internal tendon on my next bowl.

[John Keeton]

The internal "tenon" is referred to as a recess, and like John J., I use it quite a bit on specialty pieces. Frank Penta's multi-axis platter treatment is a popular item!!

[John K Jordan]

The internal "tenon" is referred to as a recess, and like John J., I use it quite a bit on specialty pieces. Frank Penta's multi-axis platter treatment is a popular item!!

Nice! You don't hang out with Frank very long without finding a texturing tool in your hand!

For anyone interested, Frank Penta's instructions for the multi-axis platter base is the second one on this page:

http://www.woodspriteturnings.com/si...ocman&Itemid=7

JKJ