The best and only chuck you will ever need?

[Hood]

I aquired a rather unusual Pratt Burnerd 10" chuck the other day. Pretty rare I think. It is a 4 jaw independent chuck with a self centering scroll as well. Best of both Worlds. Like a 4 jaw crossed with a 3 jaw. Could also be used like a Griptrue as well.
Shame I didn't take before pics. Rusted solid. Soaked in Kero and finally sorted it. No wear at all. Silky smooth.
Flipping heavy considering there is no backplate. 50kg.
I just happen to have a D1-8 lying around so ideal for my H20.
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That is a very handy chuck if it is working the way I think I am seeing it. Basically lower half of jaws on the scroll and then the tops can be adjusted individually?

 

[Pete.]

I was watching a ROHM chuck of similar design on eBay, but looked better built and was certainly in better condition.

Got involved in doing something and the auction end came and went. Sold for something daft like 40 quid.

 

[fizzy]

That is a very handy chuck if it is working the way I think I am seeing it. Basically lower half of jaws on the scroll and then the tops can be adjusted individually?

The full width of the jaw carrier is on the scroll. Then the jaw itself can move in and out like a normal 4 jaw.
Chuck has never been used. No backplate. It's mint underneath.
Just lifted a 12" 3 jaw on a D1-8 and it is half the weight

 

[nickk]

Here’s mine,only s/c jaws though,not the gem that @fizzy landed,had it 22 years,from a bloke from London attending a Staffordshire motorcycle show.

 

[Erie Fred]

s/c = self centering

I understand what S/c means.
Any Self centering chuck is not as accurate as a 4 jaw.

 

[Pete.]

I understand what S/c means.
Any Self centering chuck is not as accurate as a 4 jaw.

Yes, but @nickk specifically said he uses a s/c 4 jaw for holding square stock for non precise work and questioned it.

 

[God mode restorations]

Probably a Tudor, serrated top jaws can be placed where you want then scroll adjusts?

Hood. You are indeed correct. Made in England. Tudor concentric chuck. I have the original chuck key

 

[God mode restorations]

That jaw mounting is used on power chucks, does yours have a scroll ?

Yes it does. And the original key. Now going to have to restore it...fizzy fault lol

 

[pressbrake1]

Four jaw sc are good for short pieces and thinner wall pieces

 

[God mode restorations]

Well I have checked most of the chucks I can get to. There's others that are buried amongst other stuff. And not yet have I found one fizzy....did find a crawford hydraulic one and some collets that need sorting

 

[fizzy]

Well I have checked most of the chucks I can get to. There's others that are buried amongst other stuff. And not yet have I found one fizzy....did find a crawford hydraulic one and some collets that need sorting

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I had never even heard of one. I still can't get over the weight of it. Must have cost a fortune.

 

[God mode restorations]

I had never even heard of one. I still can't get over the weight of it. Must have cost a fortune.

Yer some chucks are monster heavy. Heavier the better means they are made proper

 

[Jan-DIY]

Discovered these one some months ago.
Unfortunately I do not have a matching spindle.

 

[Johnnybravo]

Collet chucks are the way to go. Accuracy really improves and your electricity bill goes down dramatically as you are not constantly accelerating and de accelerating dead weight. Since I put a collet chuck on the Cnc lathe, there has been a marked reduction in my electricity bill.

 

[fizzy]

I love collets. Have a huge selection of 5C and a Jacobs Rubberflex.
Never seen those collets before. What type are they?

 

[Johnnybravo]

I understand what S/c means.
Any Self centering chuck is not as accurate as a 4 jaw.

Bull…


Three jaw griptru will be just as accurate. Most four jaw chucks are abused from over tightening of the individual jaws. The jaws become bell mouthed and you land up with a set up that clocks ok ,but lacks rigidity because the bar is only clamped at the back of the jaws.

 

[Hood]

Soft jaws are my preferred method of clamping if I need accuracy. Obviously odd shaped parts will still require a 4 jaw but even then I sometimes just through the chuck in the mill and mill out the soft jaws to weird shapes.

 

[Johnnybravo]

Soft jaws are my preferred method of clamping if I need accuracy. Obviously odd shaped parts will still require a 4 jaw but even then I sometimes just through the chuck in the mill and mill out the soft jaws to weird shapes.

You don’t even need to put the whole chuck in the mill
Whoever said four into three doesn’t go ,didn’t have any sense of imagination

 

[Jan-DIY]

I love collets. Have a huge selection of 5C and a Jacobs Rubberflex.
Never seen those collets before. What type are they?

Mine is a burnerd multi size.
Awesome made quality.

 

[GraemeVW]