vicmarc bowl jaws

[smiife]

Hi guys,
I have a set of bowl/cole jaws from vicmarc , today
was the first time I have used them , they come with
a set of screws but when i put the longer screws in
the bowl jaws would still move from side to side !
and they just didn, t seem right to me !
My question is do i have the wrong screws?
Does anyone know where i am going wrong?
Has anyone had the same problem ?
I did use the bowl/cole jaws but with the ordinary
small screws that came with the vicmarc chuck,
I only got maybe a half a turn on each smaller screws
Any help/advice would be appreciated

[bowl-basher]

I sort of remember that I had the same problem went to the "nut house" and bought some in-between but that was a few years ago
regards
Bowl Basher

[Optimark]

I have the same set of Cole Jaws, the longer screws that came with mine are used by me with no problems. The VM100 chuck screws that came with the chuck, are approximately 12mm in total length, the longer ones for the Cole jaws, are approximately 16mm long.

Mick.

[smiife]

I sort of remember that I had the same problem went to the "nut house" and bought some in-between but that was a few years ago
regards
Bowl Basher

Hi bb,
I have been trying to keep out the nuthouse............
But I know what you mean, I would have thought
when we buy these tools, chucks etc they would
come the proper fittings?

I have the same set of Cole Jaws, the longer screws that came with mine are used by me with no problems. The VM100 chuck screws that came with the chuck, are approximately 12mm in total length, the longer ones for the Cole jaws, are approximately 16mm long.

Mick.

Hi mick,
Just checked the lengh of mine and they are the same
12mm for the chuck screws and 16mm for the bowl jaws ,my chuck is
the larger vm120, so you would think they would be the same?
Something not right here !!

[Sawdust Maker]

I'd suggest that you contact Vicmarc and see what the answer might be

[smiife]

I'd suggest that you contact Vicmarc and see what the answer might be

Hi nick,
Yeah , I think I might do that tomorrow,
Thanks

[Optimark]

The jaws for the VM90/100 are different than the VM120/140/150 jaw range, well their part numbers are different anyway.

I remember when purchasing my Cole Jaw set I had to ensure that they were for the correct chuck.

I have just looked at my Cole Jaw set and cannot see anything to tell you their part number, which is a pity. I have what is called by Vicmarc, Bowl 285 part number V00640 from my chuck manual. The same size jaws for the VM120/140/150 chucks are called, Bowl 285, part number V00672.

I would suggest a call to Vicmarc to ascertain if what you have can work safely on your chuck, if so, what do you need to acquire or do to allow this to happen.

Mick.

[smiife]

Hi mick,
I used the bowl jaws with the smaller screws and
it seemed to hold ok , just not too much thread biting
In to the hole, I will get on to vicmarc and see what they
say, thanks for your thoughts ,

[Treecycle]

Have you checked that over time you have not compressed sawdust into the bottom of the holes when changing the other jaws over (if you do that). Try digging around in the bottom of the holes with a sharp object such as a scriber and see if you can dislodge anything.

[Mobyturns]

the bowl jaws would still move from side to side !

Smifie,

You say the jaws still moved side to side - but were the cap screws locked down firm?

The movement could be from the manufacturing clearance between the backing jaw slides and the chuck body. That small range of sideways movement is not normally noticed with standard jaws or even the larger 100 mm jaws on the VM90/100. However when you mount the Cole (bowl) Jaws it becomes apparent because of the much larger diameter of the aluminium jaw plates. Simple proportion - approx 8 times the movement compared to the standard 50 mm jaws; or 4 times the 100 mm jaws.

If you can't snug down the cap screws tight against the aluminium jaw plate it probably means there is gunk in the threaded holes being compressed into the hole. The holes are blind due to the machined scroll lugs on the rear of the slides.

May be time to give the chuck a clean.

Definitely not a wise move to continue using the shorter cap screws (M5 x 12 Screw, Socket Flat Head) with the Cole Jaws.

ps If anyone wishes to purchase replacements, much cheaper to group buy and purchase by the 100, for their Vicmarc VM90/100 chucks ask your bolt supplier for -

VM90/100 standard jaws - "countersunk (flat) socket head cap screw M5 x 12"
VM90/100 cole jaws - "countersunk (flat) socket head cap screw M5 x 16"

The VM120/140 use M6

VM120/140 standard jaws - "countersunk (flat) socket head cap screw M6 x 12"
VM120/140 cole jaws - "countersunk (flat) socket head cap screw M6 x 16"

[smiife]

Have you checked that over time you have not compressed sawdust into the bottom of the holes when changing the other jaws over (if you do that). Try digging around in the bottom of the holes with a sharp object such as a scriber and see if you can dislodge anything.

Hi treecycle,
I didn, t check the holes, but I will now !!
I doubt if there is any rubbish in there because I normally
give everthing a blast with the airgun when I do change jaws etc!
Thanks for your advice .

Smifie,

You say the jaws still moved side to side - but were the cap screws locked down firm?

The movement could be from the manufacturing clearance between the backing jaw slides and the chuck body. That small range of sideways movement is not normally noticed with standard jaws or even the larger 100 mm jaws on the VM90/100. However when you mount the Cole (bowl) Jaws it becomes apparent because of the much larger diameter of the aluminium jaw plates. Simple proportion - approx 8 times the movement compared to the standard 50 mm jaws; or 4 times the 100 mm jaws.

If you can't snug down the cap screws tight against the aluminium jaw plate it probably means there is gunk in the threaded holes being compressed into the hole. The holes are blind due to the machined scroll lugs on the rear of the slides.

May be time to give the chuck a clean.

Definitely not a wise move to continue using the shorter cap screws (M5 x 12 Screw, Socket Flat Head) with the Cole Jaws.

ps If anyone wishes to purchase replacements, much cheaper to group buy and purchase by the 100, for their Vicmarc VM90/100 chucks ask your bolt supplier for -

VM90/100 standard jaws - "countersunk (flat) socket head cap screw M5 x 12"
VM90/100 cole jaws - "countersunk (flat) socket head cap screw M5 x 16"

The VM120/140 use M6

VM120/140 standard jaws - "countersunk (flat) socket head cap screw M6 x 12"
VM120/140 cole jaws - "countersunk (flat) socket head cap screw M6 x 16"

Hi moby,
No,! the 16mm screws wouldn, t tighten right down
I understand what you are saying about a certain amount
of movement sideways , but this was way more than normal,
I will check and see that the holes are clean, I might see If i
can get some 14mm screws,
I did get a email back from vicmarc, the advice given was
not to use the 12mm screws, but to grind a bit off the 16mm
ones ,
Thanks for your thoughts , much appreciated

[Treecycle]

I have just gone out and measured all the components I have. I use a VM120 chuck the same as yours. The thickness of the aluminium jaw is 10.1mm and when the screw is in the countersunk hole the head is 0.7mm below the surface.
The tapped holes in the jaws are 10.8mm deep and the screws are 16mm total length from the top of the head to the end of the thread. The thread of the screw should only need 6.6mm depth in the jaw to tighten up properly, but you should have 10.8mm.
Hope this helps with checking things out.

[smiife]

I have just gone out and measured all the components I have. I use a VM120 chuck the same as yours. The thickness of the aluminium jaw is 10.1mm and when the screw is in the countersunk hole the head is 0.7mm below the surface.
The tapped holes in the jaws are 10.8mm deep and the screws are 16mm total length from the top of the head to the end of the thread. The thread of the screw should only need 6.6mm depth in the jaw to tighten up properly, but you should have 10.8mm.
Hope this helps with checking things out.

Hi treecycle,
Thanks for your measurements, I have compared them
and mine are excactly the same ???
I measured the bowl jaw on the chuck with out the screw
in and It is 20mm ,,,,,, the screw is 16mm ,,,, so why won, t
It tighten up, all holes are clean , so not too sure what
to do next......any suggestions would be appreciated!

[Treecycle]

Have you tried screwing the screws in by hand without the jaws in place to ensure the thread is correct? You should be able to screw them in with your fingers until they bottom out in the thread, if not there is most likely a problem with the screws you received. Maybe they are 3/16" instead of 5mm.

[smiife]

Have you tried screwing the screws in by hand without the jaws in place to ensure the thread is correct? You should be able to screw them in with your fingers until they bottom out in the thread, if not there is most likely a problem with the screws you received. Maybe they are 3/16" instead of 5mm.

No I haven, t ......but I will try that thanks for your idea !