Thread: Bowl turning mistake

So the jaws I have currently for the VL100 don’t fit the VL120? I can’t imagine if he using the 120 for anything other than bigger bowls so perhaps I can just away with one VL120 with dovetail or stepped jaws and the other vl100s for smaller bowls and pen work etc

Originally Posted by delbs

So the jaws I have currently for the VL100 don’t fit the VL120? I can’t imagine if he using the 120 for anything other than bigger bowls so perhaps I can just away with one VL120 with dovetail or stepped jaws and the other vl100s for smaller bowls and pen work etc

Yes, VM have one range of jaws for their VM90/100 chucks and another range (larger sizes) for their VM120/140/150 chucks and are not interchangeable. That is one of the disadvantages of the VM chucks/jaws.

Nova chucks don't have that issue. The downside of the Novas is that they don't offer larger sizes above 130mm, whereas VM go up to 223mm. But you don't need such large jaws very often.

The VM100 jaws range can handle reasonably large pieces and you may not need a VM120 chuck immediately (or often).

The VM120 chuck is a large chunk of metal and I only use mine when I'm turning quite large pieces.

Originally Posted by TTIT

Just to throw the veritable cat amongst the pigeons (just to see what happens!) - I rarely if ever turn bowls on a tenon - always use a recess, sometimes only 3 or 4mm deep depending on the timber, and use the jaws in expansion mode. Have only ever lost one bowl which I turned too thin (sub 2mm) and I use the 'rim' that remains to carve the feet from.
Now going to duck and dodge the abuse from all the nay-sayers!

Fishing? Not too many bites.

The issue in the tenon vs recess debate mostly comes down to the turner's skill & experience often leading to an inappropriately sized tenon / recess for the piece being turned. Technique & skill level play a very significant role in keeping the blank on the chuck.

Skilled turners should be able to use both a tenon and a recess to suit the intended design of the piece. Tenons don't work so well for say a bowl that is to be supported by feet, as the tenon diameter is restricted by the maximum opening of the jaw set. A recess mount permits a much larger ring to be turned to cave away for feet.

Aggressive roughing cuts require a robust tenon / recess. If a delicate mount is used, then the cuts must be adjusted likewise to be refined, almost delicate cuts, preferably with a very sharp tool.

Richard Raffan is perhaps the most widely recognized exponent of gripping blanks / bowls on seemingly impossibly small tenons / recesses. Other bowl turners worth following are Stuart Batty - Stuart Batty - Simple Bowl Turning - YouTube ; Glenn Lucas Turning a wooden salad bowl with Glenn Lucas - YouTube (excellent concise explanation of process.)

Originally Posted by Mobyturns

The issue in the tenon vs recess debate mostly comes down to the turner's skill & experience often leading to an inappropriately sized tenon / recess for the piece being turned. Technique & skill level play a very significant role in keeping the blank on the chuck.

All turners, even the most experienced ones, lose a piece off the chuck from time to time. I've even seen RR hoik a few off the chuck!

New turners lose them because they are doing something wrong. Experienced turners know what to do but occasionally push right up to the failure point and from time to time beyond it. That is how they know how far they should go. It just takes a lot of turning and learning to get from novice to experienced turner.

Keeping the revs down until the blank is in balance and standing out of the firing line will help the learning experience to stay safe for both novice and experienced turner.

Originally Posted by Mobyturns

Fishing? Not too many bites.

The issue in the tenon vs recess debate mostly comes down to the turner's skill & experience often leading to an inappropriately sized tenon / recess for the piece being turned. Technique & skill level play a very significant role in keeping the blank on the chuck.

Skilled turners should be able to use both a tenon and a recess to suit the intended design of the piece. Tenons don't work so well for say a bowl that is to be supported by feet, as the tenon diameter is restricted by the maximum opening of the jaw set. A recess mount permits a much larger ring to be turned to cave away for feet.

Aggressive roughing cuts require a robust tenon / recess. If a delicate mount is used, then the cuts must be adjusted likewise to be refined, almost delicate cuts, preferably with a very sharp tool.

Richard Raffan is perhaps the most widely recognized exponent of gripping blanks / bowls on seemingly impossibly small tenons / recesses. Other bowl turners worth following are Stuart Batty - Stuart Batty - Simple Bowl Turning - YouTube ; Glenn Lucas Turning a wooden salad bowl with Glenn Lucas - YouTube (excellent concise explanation of process.)

I have one of Bruce Leadbetters recess chuck, originally designed for high schools. I dont use it often but have only lost one bowl over the years. My tenons are nearly always small as they are the foot, the only variation would be carved feet.

They haven't been mentioned yet, but I think it's worth suggesting face-plate rings as a practical alternative in some situations.

I mount them on the face that will be the rim of the bowl (not the foot) so when I start hollowing it'll remove all signs of the screw holes. This means I can comfortably shape the outside and get away with a smaller recess or tenon than I'd have needed if it had to cater for the roughing out phase.

Best of all, they can frequently be safely used on checked/split sections - which will be turned away at later stages - without worrying about whether a turned tenon/recess would fail.

Originally Posted by delbs

So the jaws I have currently for the VL100 don’t fit the VL120? I can’t imagine if he using the 120 for anything other than bigger bowls so perhaps I can just away with one VL120 with dovetail or stepped jaws and the other vl100s for smaller bowls and pen work etc

I ran with a single VM100 chuck for many years, very slowly adding different jaw sets as and when needed for the direction my turning was heading. Generally I picked these jaw sets up (one at a time) at wood working shows in Victoria when Carrols were in attendance; thereby eliminating expensive freight.

My thoughts were that I'm not doing this for money, so time isn't an issue. I simply changed jaw sets over whenever needed. I ran with one chuck for about 5-6 years, not an issue.

Then I was offered some potentially large bowl material, quite frankly the VM100 was over its head, it was time to get a VM120; huge difference.

Currently I have three VM100 chucks and one VM120 chuck. I don't see me needing anything else chuck wise.

I'm also a big user of faceplate rings for bowl turning and/or getting green blanks ready for initial coring. While not as strong as dedicated screw into the spindle face plates, they are quite capable. Below is a VM120 using the largest Vicmarc face plate ring with a very green (2-3 hours from felling) hunk of oak.

This is the biggest blank I've done with a chuck mounted face plate ring, heavy as, and dripping liquid even before I started turning. Probably around 65kg as two of us really struggled to lift it; also when I decided I needed a hoist of some kind.

In the first picture, you can see that the end grain has been coated with an end grain sealer. I stopped for a break and knowing how quickly oak will crack, I immediately coated the ends with this:

Carbatec End Sealer - 2ltr | Carbatec

Works quite well and if you move into green timber turning you can purchase all sorts of materials to seal the end grain, including using wood glue. I've been using this and candle wax for years to seal timber.

Mick.

Big_Oak_Blank_IMG_20190206_104729_Web_.jpg Big_Oak_Blank_Web.jpg