Thread: Bowl Chuck Problem.

That looks like a version that mounts onto the VM120 chuck, it also looks as though the jaw mounts may be incorrectly inserted. The aluminium pieces from Vicmarc are identical in dimensions, so I don't think the issue lies there.

The jaw holders are numbered 1 - 4 and need to be inserted into their correct positions, is it possible you may have inadvertently attached them in an incorrect sequence?

Perhaps a front on picture so we can getter a better view of the misalignment? I've just had a look at my VM120 chuck version, which I think is the same as yours, there is a slight variation in the gaps, but nothing like what I appear to be seeing.

Mick.

It looks to me like you’ve not got that jaw seated correctly. Open the jaws a fraction, loosen the screws on that jaw and get it to seat nicely and retighten.

Originally Posted by Optimark

That looks like a version that mounts onto the VM120 chuck, it also looks as though the jaw mounts may be incorrectly inserted. The aluminium pieces from Vicmarc are identical in dimensions, so I don't think the issue lies there.

The jaw holders are numbered 1 - 4 and need to be inserted into their correct positions, is it possible you may have inadvertently attached them in an incorrect sequence?

Perhaps a front on picture so we can getter a better view of the misalignment? I've just had a look at my VM120 chuck version, which I think is the same as yours, there is a slight variation in the gaps, but nothing like what I appear to be seeing.

Mick.

I can not find any where the 1-4 numbering.
I have tried putting them in different positions with same results.





Definitely meant to fit the vm100 Chuck.

Sent from my iPhone using Tapatalk

Originally Posted by Colin62

It looks to me like you’ve not got that jaw seated correctly. Open the jaws a fraction, loosen the screws on that jaw and get it to seat nicely and retighten.

Tried that didn’t work.[emoji22]


Sent from my iPhone using Tapatalk

Vm150 jaw on the vm100 bowl jaws.




Sent from my iPhone using Tapatalk

I assume that you have double-checked that the jaws are all truly flat?

You did say that they were stored flat on a shelf for years... I've done the same only to come back and find that at some time a loose item has somehow managed to wedge under a corner of 'em. Never been a problem for me, but I imagine there's always a risk the bottom-most could bow or twist.

As a matter of interest... you say you've moved 'em around to different positions with the same result? Did you take note if it's the same jaw that is out each time or is it always the last jaw you fit?

If it's always the last jaw, then you probably simply haven't found the right positions yet. There are 24 different combinations possible. (It'd be my luck that in your shoes it'd be the 24th possible attempt before it fell in place. )

And if it is just that, I strongly recommend you marking 'em correctly for next time. Yours should be numbered, I've no idea why they aren't.

I don't think it's a problem with jaws being in the wrong order . I have a set for the 120 chuck and I am pretty sure there are no numbers on the jaws . After all these are rated at a maximum speed of only 1000rpm although I notice yours are marked max 800
Ted

I agree with Optimark (#2). The issue imo is debris between the backing jaw and cole/bowl jaw segment, and/or there is some damage to the matching backing jaw slots / or bowl jaw segment ribs that is not permitting them to seat correctly. Even one chip of wood can cause that amount of misalignment.

AFAIK the bowl/cole jaws have not been, and are not marked 1-4. They are cast, not machined, are all identical and should fit in any position.

The chuck backing jawsets / slides are marked and must be installed in the correct sequence, because of the manufacturing techniques used to produce them - turned as a whole then milled into 4 quadrants.

I doubt that is a manufacturing issue with the backing jaws, or incorrect installation sequence, if other jaw sets fit correctly and if the chuck has not been disassembled / reassembled since purchase.

I marked the jaws 1-4 , coincidentally jaw 1 on No 1 on chuck etc was the best.
I used a brass brush on chuck by and back of the jaws made no difference.

I bought the chuck new never pulled it apart.

Using a granite surface plate 1 is the worst and 4 is not the best, 2 and 3 are perfect.









Sent from my iPhone using Tapatalk

Those plates are bent, I guess the shelf they sat on for years had a "Heavy" coat of dust. Try bending them straight or contact Vicmarc

Send the pictures to Vicmarc and contact Marco about a replacement, it is a faulty plate and will not be safe to use.

Originally Posted by Richard Hodsdon

Those plates are bent, I guess the shelf they sat on for years had a "Heavy" coat of dust. Try bending them straight or contact Vicmarc

I wouldn’t risk bending them - a visit to the doctor for stitches will probably cost as much as a new set of jaws.

If they’ve been sitting on a shelf and not being abused, I can’t see Vicmarc not sorting the problem out.

Colin, you are right, they look very much like a casting and bending cast Al will probably break them, if they were machined from a billet then bending them would be simpler.