Jumbo jaws - Vicmarc or Stronghold?

[Alan Heffernan]

I have both Oneway Stronghold and Vicmarc 120 chucks.

I am going to add a set of jumbo jaws in the nominal 14" range for use on my PM3520B lathe. So I must decide which set to buy.

Have any of you used both the Stronghold Jumbo Jaws and the Vicmarc Adjust-Jaws? And if so, which do you prefer?

I will admit I have an uninformed preference but your experience/insight/advice would be very much appreciated.

Vicmarc:343224 Oneway:343225

[Justin Stephen]

I seem to recall that, at least at one point, you could get extensions for the Vicmarc jaws that would let you get them really big but that no such extensions were available for Oneway's biggest set. My memory could be faulty, however.

I wouldn't mind having a set of jaws that could hold 18"-20" platters if someone actually made them. I may have to just make my own someday. My donut chuck maxes out at ~18".

[Jeffrey J Smith]

For me, it all comes down to the buttons - and at that point, it's horses for courses.

I've used both - don't have a preference either way - I own the Oneway and have used the Vicmark version a few times (owned by a friend). They're pretty much identical in use, but I do prefer the shape of the square buttons of the Vicmark version. Probably doesn't make a whole lot of difference, and it's been a while since I've used any jumbo jaws (I generally prefer vacuum chucks for what I'd do with the jumbo jaws) but, as I recall, they seem to have a larger undercut and the shape seems to allow a greater contact area. I also like the sturdy metal inserts of the Oneway buttons - That said, it's horses for courses - choose whichever on you get a good deal on. I bought the Oneway Jumbo Jaws on clearance several years ago - got a killer deal, so they sit in the drawer awaiting their next use right next to the ones for the Oneway Talon...need to have a garage sale one of these days.

Just a thought, but I should check to see if the Vicmark buttons will fit on the Oneway jaws....

if it comes down to the buttons as the only real, functional difference, I'd say buy the ones that fit the chuck you'll prefer to use the jaws with.

[Leo Van Der Loo]

They are almost identical, but I do like the Oneway buttons best, as I have at times stacked them on top of each other to get a grip farther out, just the other day I tripled them, with the metal core going from top to bottom stacked and screwed down, they are sitting solid on top of each other.

Since I have 3 sizes of jumbo and the Mega jumbo jaws, plus a new set of buttons bought recently that were getting rather rough after years of abuse, the old ones are sill good for stacking, so lots of bumpers here :D

As for extensions, I have a set that I made myself from MDF, have used them, but not very often, as the Mega jumbo jaws are pretty big already, holding up to 15” on the inside of a turning, stacked buttons picture here.

343228

[Bob Bergstrom]

Save your money and buy a vacuum chuck. Almost any thing that holds a vacuum can be done on a vacuum chuck. Natural edge, square or round. I've used them and felt that the buttons of rubber vibrate. If the bowl is out of round they will most likely launch it. Fugal Vacuum pump is a good value and you can make your own chucks. I've turned a natural edge 23" bowl on a vacuum chuck. I've made vacuum chucks out of plastic pipe, to 2 gallon paint buckets. Just my nickels worth. Keep the change!!

[Bob Coates]

Here is a set that I made.
http://www.sawmillcreek.org/showthread.php?246516-Large-jaws-using-wedge-sled
Bob

[Tom Albrecht]

Save your money and buy a vacuum chuck. Almost any thing that holds a vacuum can be done on a vacuum chuck. Natural edge, square or round. I've used them and felt that the buttons of rubber vibrate. If the bowl is out of round they will most likely launch it. Fugal Vacuum pump is a good value and you can make your own chucks. I've turned a natural edge 23" bowl on a vacuum chuck. I've made vacuum chucks out of plastic pipe, to 2 gallon paint buckets. Just my nickels worth. Keep the change!!

The key words up there are "Almost anything that holds a vacuum". A lot of stuff will not, like bowls and vessels with voids. I've been vacuum chucking for years and am also in the market now for a Jumbo Jaw set.

[robert baccus]

Come by my shop (the swamp) and I'll give you a set barely used. Gave it away 3 times--keeps coming back. Bought it when Nova introduced the first 4 jaw chuck with many accessories. Used the Jumbo jaws, the 3&4" jaws maybe 3 times each. Extremely time consuming and requires a new$$ chuck to be practical. I turn a few bowls--large-- and mostly vases & urns to 120# green --using several homemade friction chucks. Hollowing to 16-18" using 2'Jaws and heavy glueblocks. Takes a fraction of the time to set up and a proper friction drive makes throwing an entire bowl/vase almost impossible. No comparison if cost is a factor. I probably have 6-8 friction drives with extensions for various lengths. Vacum chucks I an clueless about.

[Leo Van Der Loo]

I have a vacuum pump and chucks for it, if I can still find it ;), as I hardly ever use it, some like it and I don’t.

With returning dried bowls I want to be able to lift one side or the other (I use wedges for that) or hold warped pieces with openings,

Like these bowl that have warped, I can and do adjust the bowl so the are centered exactly on top and bottom by moving and lifting sides, my bowl walls can be thinner (less splitting) this way and I’m still able to return them.
343269

All kinds of pieces and sizes can be held and turned in Jumbo jaws and are more securely held against sideway shifting than with a vacuum chuck.
343271 343270

yes some pieces are OK to hold with a vacuum chuck,but also very easily with the Jumbo jaws.
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[robert baccus]

Crazy old cajun says there are many ways to skin a nutria rat. If it works, do it.

[Alan Heffernan]

Okay, as the OP let me admit that I have also studying vacuum chucks and intend to flesh one of those out as well. (I am going to start a separate thread on that!)

Meanwhile I am still interested in acquiring a set of jumbo jaws and thank all for their posts and insights. As always, thanks to Leo for all the descriptive photos.

[robert baccus]

In my misspent youth (50's) i did make an extension for my Nova jumbo jaws out of Baltic Birch 1/2" plywwod that worked very well for larger bowls. Gave them away also.

[Peter Blair]

Pleeeaasse let us know when you schedule the garage sale . . . .

[Peter Blair]

Agreed Tom. I use both as well.

[carl mesaros]

Save your money and buy a vacuum chuck. Almost any thing that holds a vacuum can be done on a vacuum chuck. Natural edge, square or round. I've used them and felt that the buttons of rubber vibrate. If the bowl is out of round they will most likely launch it. Fugal Vacuum pump is a good value and you can make your own chucks. I've turned a natural edge 23" bowl on a vacuum chuck. I've made vacuum chucks out of plastic pipe, to 2 gallon paint buckets. Just my nickels worth. Keep the change!!
I agree Bob. I have two sets of jumbo jaws and then spent big bucks on a Longworth chuck. All worked as long as I was supported by the tail stock as long as possible.
Then with the purchase of a Holdfast vacuum system with two chucks, my jumbo jaws and Longworth have been gathering dust. I realize the vacuum system may not hold everything but so far it's been my go to for finishing bowl bottoms.
The vacuum system is so much quicker to set up and far more secure. My opinion only.

[Leo Van Der Loo]

I agree Bob. I have two sets of jumbo jaws and then spent big bucks on a Longworth chuck. All worked as long as I was supported by the tail stock as long as possible.
Then with the purchase of a Holdfast vacuum system with two chucks, my jumbo jaws and Longworth have been gathering dust. I realize the vacuum system may not hold everything but so far it's been my go to for finishing bowl bottoms.
The vacuum system is so much quicker to set up and far more secure. My opinion only.

Of course a rough turned bowl isn’t nice and round, but warped and your vacuum chuck doesn’t just fit to that warped bowl.

Now later when you have re-turned the bowl and it is nice on round and smooth, yes then your vacuum chuck will hold it,

it is the steps needed before it is nice and round that the Jumbo jaws prove their value by being able to hold oval and warped bowls :)

[carl mesaros]

Of course a rough turned bowl isn’t nice and round, but warped and your vacuum chuck doesn’t just fit to that warped bowl.

Now later when you have re-turned the bowl and it is nice on round and smooth, yes then your vacuum chuck will hold it,

it is the steps needed before it is nice and round that the Jumbo jaws prove their value by being able to hold oval and warped bowls :)


Very true Leo, but I usually remount my rough turned bowls using the original tenon, return the bow,l and then use the vacuum chuck to finish the bottom.

[John Beaver]

The Vicmarc buttons have convex and concave sides so you can use them for outside or inside mounts. Of course there is a good chance they both use the same thread sizes so you could always buy the buttons separately.

One thing to keep in mind. If you get the big jaws, you need a long wrench to reach down to tighten the jaws. The geared wrench for the Oneway may not reach so you could not spin it freely. You would have to go one turn at a time. It would be easier to get a long wrench for the Vicmarc.

[Leo Van Der Loo]

The Vicmarc buttons have convex and concave sides so you can use them for outside or inside mounts. Of course there is a good chance they both use the same thread sizes so you could always buy the buttons separately.

One thing to keep in mind. If you get the big jaws, you need a long wrench to reach down to tighten the jaws. The geared wrench for the Oneway may not reach so you could not spin it freely. You would have to go one turn at a time. It would be easier to get a long wrench for the Vicmarc.

The wrench of the Oneway Stronghold chuck does reach, even with my Mega Jumbo jaws John, only when I mount the extensions do I have to slide the crossbar through the wrench to keep on turning, still do not need to take the wrench out of the chuck :)

[Clint Baxter]

I have both and use them both. If either were available, (not already holding something), I gravitate to the Stronghold because of its buttons. The round rubber buttons are much easier on you should you ever contact them while turning. I got bit by the Vicmark squares, and prefer to avoid a reoccurrence. I still will use the Vicmark, but usually only when my Stronghold is otherwise occupied.

IIRC, the Vicmark has a little additional reach, which sometimes then gets the call as well.

Clint

[John Beaver]

Good to know Leo.
The standard Vicmarc key can be a little short at full extension of the jaws.


The wrench of the Oneway Stronghold chuck does reach, even with my Mega Jumbo jaws John, only when I mount the extensions do I have to slide the crossbar through the wrench to keep on turning, still do not need to take the wrench out of the chuck :)