Rohn style drill chuck

[frank horton]

I need to upgrade my 240v Hitachi drill with a new chuck....but can't find this style to fit...photo1

all I can find is something similar to the orig which is useless...photo 2

I want the precision type jaws....with a 1/2" UNF chuck mount...
Have a big job coming and need to hold 5mm drill bits tight....
The local tool supply shop only has garbage....
The orig chuck is still good but sick of slippage...
if I wanted bigger size of drill I'd buy em with three flats machined into the drill shaft but I cant get any in the 5mm size...
Not so worried about cost, it's just gotta work.....
Help PLEASE....

 

[Kram]

I bought this to upgrade my drill a while back, its decent, however its 3/8 unf which are much harder to find in 13mm.

Jacobs SDS Drill Chuck Keyless Steel Body 500 Series 1.5-13mm + 3/8 SDS Adapter | eBay UK

Jacobs 500 Series 1/2" Keyless Chuck + SDS Adaptor. Jacobs Patented Ratchet Locking System inside - Great bit holding and prevents bit loosening under high vibration applications. Anti-lock nut prevents chuck from locking open.

www.ebay.co.uk

This second one appears to be 1/2" unf

Pardon our interruption...

 

[eddie49]

You need a Metabo Futuro Top in 1/2" - 20 mount.
E.G.

Metabo 1.0 - 13mm Futuro Top Keyless Chuck 1/2" x 20 UNF - Protrade

Metabo 1.0 - 13mm Futuro Top Keyless Chuck 1/2" x 20 UNF - we stock a huge range of tools & consumables for professional trades. Free delivery on orders over £50!

www.protrade.co.uk

or

Pardon our interruption...

or

https://www.amazon.co.uk/Metabo-636226000-2-inch-Keyless-Futuro/dp/B00069LBM6?th=1

or

Pardon our interruption...

Only the Futuro Top ( not "Plus" ) chuck has the jaw style that you want.

EDIT

The Rohm 871050 is also good:

Rohm 871050 Keyless Drill Chuck 1/2 Inch x 20 Mount 13mm Capacity

SUPRA Type S Quick-action Drill Chucks. A self tightening flat jaw drill chuck suitable for stationary and hand-operated drills.Technical Specification:Concentricity fluctuation: 0.25External diameter mm: 40.2Length closed mm: 83.6Length opened mm: 76.3Mount mm: 1/2 inch -20Size: 13Type: S

www.lubricantsupplies.co.uk

 

[hotponyshoes]

Dewalt Extreme bits have flats in the 5mm size.

 

[Kram]

Anyway its not the style of jaws that makes a chuck any good. I have several of the first type for the lathe and they can slip, particually on small bits. They are better than most cheapy drill chucks but far from a decent quality one. You'd be better looking for a decent branded quality chuck.

Another option is an ER16 collet holder with a larger shank, is less likely to slip. Than a 5mm shank.

The chuck on my Makita HP001 is very good, tho the ratchet inside seems it can be overtightened and not want to loosen off when I had a 13mm bit in it. More testing needed...

 

[frank horton]

Dewalt bits are not available here....
For decent drill bits I can only buy Austrian made, non of which have the ground flats...
Did try to write to the factory but impossible to find a customer service email....just gave up....
I can't or won't mill flats on 5mm drill bits in house....bigger sizes no probs....
thanks for the replies....