Well, War is Over (for now)

[Joe Vincent 63]

Ended up remounting the blank via the faceplate, and it broke off again. I've come to the conclusion that the size of the foot for the Vicmarc standard jaws is just too small (2 5/8) for a bowl that size. Based on Mike Mahoney's video, the foot should be at minimum 40% of the diameter of the blank, which in my case is 8+ inches. While I am sure you can use smaller, it seems like a reasonable guideline to follow. Needless to say, after the last time if broke off (catch again), I cut a recess instead for the jaws, and had no additional issues holding the blank.

Next I had to get the faceplate off, so I ended up basically coring around it with screws still intact with a thin kerf parting tool. I still have to dig the screws out, but at least I could continue.

Needless to say, I learned a lot in preparation for the remaining blank, but I'll have the proper jaws next time. Thanks to everyone for all of the comments, and advice, it really helpful as this was my first really large bowl, as well as using a faceplate. I've included a few pictures of the battle along the way!

It is now resting peacefully in a bag with shavings to dry. Hopefully it won't really fix me, and crack as it dries :eek: !

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[Reed Gray]

Tenon or recess? For a 23 inch bowl, I have a big set of jaws for my Vicmark that are about 5 inches across. I had no problem with it in a recess, turning and coring a 22 inch madrone bowl. I generally want 1/4 to 1/3 the diameter for a recess. I also used the Oneway 6 inch face plate, and 1 1/4 inch decking screws. I would want the tailstock attached for one that size. It helps distribute the loads between headstock and tailstock bearings, rather than all on the headstock.

robo hippy

[Joe Vincent 63]

I was using a tenon the first two times around. I used a recess after if broke off the tenon the first two times.

Normally I use the tailstock as well, but I had to go to the end of the lathe since it was over 20", so no tail stock. Instead, I used the oneway 6" faceplate with 3" special screws. They got stuck, broke off, and stripped, so I couldn't get them out (had to dig down around as in the picture). I probably should stop using a tenon for that sized bowl. The vicmarc standard jaws held fine in a recess (but that was after the blank was turned round).

Are your vicmarc 5" jaws standard or the "mega jaws"?

Joe

[Bob Bergstrom]

209927Careful turning big is addicting. Here is a way I used to help support the ways on the lower level. It is a hydraulic table with a piece of 2x10 to spread the pressure out from the lathe. It will help cut some of the vibration when you get to the finishing cuts on big bowls. It doesn't take too much to cause chatter inside some of the big ones.

[Baxter Smith]

Congrats on getting it done! Bigger jaws for the next one will help considerably!

[Bernie Weishapl]

Congrats on getting it to the drying bag. I bought a grizzly chuck and put the big Vicmarc jaws on it. On the big stuff can cut a 4 3/4" tenon.

[Reed Gray]

My big Vic jaws are the standard ones, not the ones that extend out about two inches. That would put things too far away from the headstock.

robo hippy

[Dave Ogren]

I have turned a 21" dia. X 7 3/4" tall maple bowl with a 5" Vicmarc chuck with standard jaws in a 2 5/8" dia. recess, no tail stock and had no troubles at all.

[Jim Burr]

and no lung or face protection!? Wow. That's gonna be one really big bowl suitable for a Lord of the Rings marathon of popcorn!

[robert baccus]

Try a glue block screwed to a faceplate. works even on grren wood endgrain as in a vase blank.----------------old forester

[terry mccammon]

Be cautious with decking screws, they can be brittle. They are not engineered for lateral torque (sideways twisting). They are about hold the deck down to the frame.