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View Full Version : odd threads,ship work and Euopeans!!



motorworks
09-28-2010, 07:05 PM
Well
I have a ship in on refit...she was built in Europe
Well the first job was to shorten the shaft on the I-beem trollies
(They were hitting on some pipes and the pistons had to come out first)
Take a quick measurement and back to the shop. Cut off the shaft and measure the old thread to see what size it was so I could cut a new thread and reuse the nut....It gets good...
28.5-3.5 mm. Well the guys who came up with this were dam sure that you would not get that size at the Local hardware store in Canada!!
Chesus it hard enough to get 10-1.25 !!
What do the designer/engineers smoke over there!! LoL
eddie

oldtiffie
09-28-2010, 07:41 PM
I make it 28.5/25.5 = 1.1220 ~ 1.125 = 1 1 /8" diameter

and

3.5/25.4 = 0.1378 ~ pitch ~ 7.257 ~ 7 1/4 tpi

As it was made in Europe it is probably metric but if you have an "inch" lathe and lead-screw, 1 1/8 OD x 7 1/4 tpi will get you there.

With a normal inch lead-screw and threading dial,you can use the same spot on the threading dial to "drop in" and engage your half nuts. No need to keep the half-nuts engaged and reverse the lathe.

motorworks
09-28-2010, 07:49 PM
O-T
Job Done...did two...The Colchester 15 x 50 will cut all threads and their grandmother!!(best tool room out there !! mine is a '73 model)
Just ranting about the design!!
eddie

Dr Stan
09-28-2010, 08:34 PM
What do the designer/engineers smoke over there!! LoL
eddie

Probably the same as the auto engineers do in North America. :eek:

wierdscience
09-28-2010, 08:53 PM
I would have chopped it off and threaded it 1-1/8-7 just to piss the next guy off:D

oldtiffie
09-28-2010, 09:17 PM
Dunno about that WS.

7tpi is easier to use a thread-chasing dial with (every quarter turn) than 7 1/4 tpi (only one place on the threading dial) so my guess is that you'd be doing the next guy a favour - and pissing yourself off in the process!!