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smidsy
1st Nov 2004, 03:57 PM
Hei Guys,
One of the problems I have with my Bonham clone chuck is that it wouldn't grip the screw properly when I tried to mount a peice of timber.
I plan on getting a Vicmarc chuck anyway but it will be a case of when I have the money.
I was just wondering if the Vicmarc screw plate would be useable with my chuck - I plan on getting the plate when I get the chuck anyway but I'm thinking it might be a cost effective way to keep my chuck going until I get the $$ for a Vicmarc.
Cheers
Paul

rsser
1st Nov 2004, 04:13 PM
I guess this is a question of radii and dovetail angle, and I can't help sorry. You can email the factory - www.vicmarc.com

Clearly the screw design is important; can only suggest what you've already tried, and reduce the hole diameter.

An alternative when you do get the Vicmarc is to use the shark jaws and faceplate rings - saves time mounting and allows you to have several bits of work on the go at once.

Cheers,

smidsy
1st Nov 2004, 05:10 PM
Hei Ern,
The trouble I have with the Bonham is that it wouldn't grip the screw tight enough to screw all the way in to the timber - which is a block of wet marri.
I drilled the hole the same thickness as the solid part of the screw, the instructor at the turning club thinks I may not have drilled a big enough hole but I've used that same size hole to mount rock hard dry hard jarrah.
Cheers
Paul

ptc
1st Nov 2004, 05:41 PM
Hole to small
ptc

rsser
1st Nov 2004, 06:09 PM
Yeah, drill her out one more size and then see how you go. I remember having to vary the hole size when I was in the Ark too ;-}

Happy to lend you my Vicmarc screw if you reckon it's a screw design issue.

(Jarrah's a pretty open grained timber; I'm not sure your comparison holds, 'n as I remember a 64th or 32nd drill size cld make a lot of difference).

(Edited several times; can only plead slow moving mental cogs)

Woodencrux
1st Nov 2004, 09:24 PM
Depending upon the size of the timber you are mounting, you can reduce the total depth the screw needs to enter by adding a packing piece of MDF/ply between the work and chuck. It is amazing how strong a screw holds with just a few turns (provided the timber grain is tight enough to hold). I have had problems with burls and screws!
It is important to have the work tighten up against a solid surface and the raised dovetails of a chuck are not always the best.
Another option is to screw the timber to a piece of MDF/ply (several screws through the MDF/ply into work) and mount the MDF/ply into the jaws of the chuck via a recess you previously turned into it or fasten it onto a faceplate.
Regards,
Alan

smidsy
1st Nov 2004, 11:07 PM
Hei Guys,
I've got a face plate that came with my MC900 so I might use it for the first time.
I think the issue with the screw on the Cloneham chuck is that it is gripped by the inner edges of the chuck so the fit and tolerances are rather critical - probably a little too critical for a cheaply made chuck.
When I get my Vicmarc I will get one of those screw places because I think it's a way better design, bvy gripping with the jaws you have a lot more power and the tolerances are not so critical.

Thanks for the offer of the loan Ern but it's not worth the hassle of posting it back and forth. I can probably get by with the face plate and if I get desperate for a chuck there's a couple of decent ones at my turning club that I can use.
Cheers guys
Paul

smidsy
2nd Nov 2004, 06:36 PM
Hei Guys,
I e-mailed Vicmarc and they say that the screw plate should work with my chuck.
Cheers
Paul