What's wrong with Jumbo/Cole Jaws?

[Burt Alcantara]

I've read numerous posts about Jumbo/Cole jaws that always end up saying - "don't buy these," with the only reason ever given is that you will one day own a vacuum system.

Yes, one day I may own a vacuum system but that will be a long and far away day. I have too many events and projects that have priority over a vacuum system at the moment.

Every time I read about jam chucks, it seems like one is made for each turning from scraps. I never seem to be able to find these sized scraps around.

I'm looking for something to true up a tenon after drying then finish the foot when the turning is finished. I'm assuming a jumbo/cole jaw would do this. Yes?

Burt

[Paul Zerjay]

Why don't you try making a doughnut chuck? Before my vacuum, I had much better luck with that than the cole jaws

[Keith Burns]

Cole jaws are fine and work great for the purpose they were made for. They will only hold a flat top bowl and have size limits. This is the reason for other suggestions.

[Ken George]

I have cole jaws on a Vicmarc chuck and a vacuum system . Had the cole jaws first and used them a lot. Although the vacuum chuck gets the most use now, I do use the cole jaws occassionally. Most recently on a burl that couldn't be mounted on the vacuum system. It wouldn't hold any vacuum, or anything else that flows! My cole jaws have the red rubber clamping pads and I have never had a problem with marking. I found the hassle of making and using jam chucks and donut chucks frustrating which is why the cole jaws were bought. As funds became available the vacuum system was purchased.

PS I have been a member here for quite awhile but strayed away and just returned a few weeks ago.

[Chris Barton]

I have a set of Cole jaws on a chuck dedicated to their use but, I rarely use it. The reason for this is that Large Cole jaws kind of beg to be spun at very low speeds. That's a lot of metal with sharp edges flying around and I've found a friction mount works better and is a lot less "puckering" to use. Plus, If you have a lathe that won't go below about 300 rpm then you're hosed.

[Gordon Seto]

Cole jaws is only one of the method for reverse turning. It will not work on natural edge bowls. If you have means to reverse turn a natural edge bowl, then you will be able to do without Cole jaws. For example, you can use friction chuck instead of jam chuck etc. With friction chuck, you can use the same block over and over.

A real Gast vacuum pump from Surplus Center is only around $90. There are ways you can make your own vacuum drums and hook up for much less than the price listed in CSUSA catalog. A mega jumbo jaw is $110. It isn't inexpensive.

Gordon

[Steven Wilson]

jumbo jaws work fine and if they fit the kind of work you do then no need for a vacum chuck.

[Bernie Weishapl]

I have the Vicmarc jumbo jaws on a dedicated Grizzly chuck. I use them all the time. Yes as Chris says you have to be aware of what is going on and slow the lathe down. I generally run it around 250 to 300 rpm. I also use a donut chuck. There is a use for both as well as a vacuum chuck. I have never seen the need for what I turn so far for a vacuum chuck.