Confused, Coventry dies

Over a year ago I picked up a job lot of Coventry dies, mostly GAS, BSP, NPT formats, but some WHIT and BSF etc.

Anyway, I have finally got round to sorting them out, but in the process have a few odd ball sets. Only knowing the CH/CHS types would like information on these.

Have a set of 4 that are the same thickness as the 3/4" dies but are marked

1 and 1/2" GAS, another set same thickness marked 2" NPSH. So from these two sets assume there is a die head made of a different type meant for these.

Also a set of 6 dies marked 3 BSP that are the same thickness is the normal

1" die box. would be interested in knowing what type of head they would fit.

I do have copies of issue 1 and 23 of the Coventry die book, courtesy of a group member, but can not find within the pages dimensions of the dies for each size/type of head, so if anyone can provide this it would be much appreciated.

If anyone has a use for above dies let me know as I doubt I would use them.

-- Cheers Adrian.

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Reply to
Adrian Hodgson
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All of these are almost certainly for pipe threading dies or machines, probably not for coventry-type self-opening die heads. Do they have a makers name on them? Presto, Ega-Kut, Ridgid are all names which would suggest pipe dies. These are generally much longer than the Coventry chasers, for a given thickness.

I've just checked my book, surprised to find no mention of the die dimensions. If no-one has the answer to hand, I could go out & measure all the sizes I have tomorrow. I could even measure a Presto hand ratchet pipe die! The Coventry heads each use distinctly different die thicknesses.

HTH Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

Reply to
timleech

if it looks like one of these and has 8d written on them and 1/2 and 3/4 on the end

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it belongs to a bulldog hand rachet pipe threader and i need a set of dies for it . let me know . all the best.......mark

Reply to
mark

All the dies have the AH for Alfred Herbert stamp on them in a circle, so as far as I can tell for a similar device.

-- Cheers Adrian.

Reply to
Adrian Hodgson

And no sorry not the same dimensions as the picture

-- Cheers Adrian.

Reply to
Adrian Hodgson

Herbert also made a Patent Collapsible Tap. This took a similar chaser to the diehead, but they were different to the point of having their own grinding fixture and dimension ranges. There were 12 sizes each in Style H and P, and Style T was for taper thread over 1.5". Page 274/275 in the 32nd edition of the Master Catalogue gives the detail.

Sounds like this may have been the use for these chasers.

Regarding chaser dimensions, there is no information available in the instruction books or the master catalogues on chaser dimensions that I could find, and I have a lot of these publications here to look through.

I had a recent email exchange with a guy who wanted the information, but wouldn't accept that it wasn't available, so I left him disappointed.

Tom Martin may have more info, he has a comprehensive library of machine tool stuff.

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

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Reply to
Peter A Forbes

Just for the basic cross-sections, I've just run some calipers over some chasers and come up with:

1/4" head .1565 x .312 1/2" .500 x .25 3/4" .75 x .312 1" .875 x .375" 1 1/4" 1" x .437 1 1/2" 1.125 x .5 2" 1.5" x .625"

Obviosly based on fractional sizes.

Incidentally I have a few sets of 1 1/2" chasers and no head for them, I'm open to offers before I get round to bunging them on ebay.

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

Reply to
timleech

Haven't checked the dimensions, but that looks very similar to those for Ega-Kut & Presto ratchet dies. AFAIK presto are still available, but not cheap. Try a Google search.

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

Reply to
timleech

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