snapped pin in wooden block

[Alastairdent]

Used a wooden block (tuffnol roller, steel pin, wooden body) the other day to redirect a rope to a winch. We snapped the pin that goes through the roller.

Do you think I should try to salvage the block by replacing the pin? The wood looks sound, just the pins are rusty.

 

[Mirelle]

Yes; the pin must have been badly worn to snap.

Try and drive it out; if the sheave is still in the block it should be possible to get a hacksaw blade (case need, a junior hacksaw blade!) alongside the sheave and saw through the pin to remove the sheave, then drive the remains out with a drift.

I replaced all mine with s/s rod.

 

[Alastairdent]

Ta.
got a handy source for s/s rod?

 

[Mirelle]

Alas, my source, 20 years ago, was my ex-father-in-law /forums/images/graemlins/wink.gif

 

[Seanick]

You can use a bolt of the right diameter, cut off the thread and make the head as square as you can from the hex head. The principle is that the sheave rotates around the pin, not the pin rotating in the block, hence the square head!
A proper job is to turn down the pin from larger stock, leaving material to make the head from.

 

[mclark]

I have had to do this a few times as well, not for a sheared pin but for a rusty/worn one. I drilled everything out a bit and used the next S/S bar size up which will tighten any wear in either the sheave or the block frame. I used the next drill size down to drill the wooden block frame and this ensured the pin was a tight fit in the wooden frame. I have some blocks that have done nearly 20 years of service now and they seem quite happy not to rotate in the frame without the square head although I agree the square is better.

 

[andrewbodenham]

[ QUOTE ]
got a handy source for s/s rod?

[/ QUOTE ]

I can strongly recommend a set-up called M-Machine, who specialise in selling small amounts of metals to model engineers and the like. They have a huge range of s/steels, bronzes, alloys etc. in a range of sections which they sell by the foot, or in the bigger sizes by the inch! No website, but ask them for a stock list. P&P very reasonable too.
sales@m-machine.demon.co.uk