Not Butting Pony Tails

Following on from my brief R&D activity to prevent Gland packing turning into a pony tail, I bought a 35mm diameter wooden dowel from B&Q. The gods must have been on my side - how often can you go to a DIY store and actually buy what you want in exactly the right size? 35mm is the same diameter as Sentinel 7109's piston rod.

Wood is a good material for winding the packing around as it grips the packing surface just the right amount without abrasion. I first drew a line along the dowel so I could see the angle of rotation. Then I pinned the end of the packing to the dowel.

I rotated the dowel to pull the packing rope around the dowel and pinned each turn either side of the line to allow me to cut one ring at a time without the remaining packing unwinding.

One end of the dowel was held in a vice to make it easier to hammer in the pins.

Packing rolled on to the dowel

Along the line drawn on the dowel, I painted some Heldite around the outer surface and sides of the packing (but not the inside surface).

Packing pinned in place

I took the dowel and its turns of packing to site for fitting into Joyce's rear left piston rod stuffing box. By taking it on the dowel, I was able to cut one packing ring at a time and fit it straight away (soaked in warm cylinder oil). This minimised the time the packing might have to become a pair of pony tail ends and it proved very effective.

Next task is to light the fire and blow out the two old right hand piston gland packings and run-in this one.

Butting Pony Tails

Recently, I wrote about Sentinel 7109's piston rod gland packing challenges but didn't have a photo to illustrate. Also I've now found a way to reduce the challenge to a reasonable level.

The photo below shows an experimental sample of the Pilotpack 4010 1/2" square section material.

Pilotpack 4010

To the right is the 'pony tail' created by cutting the 4010 without any means of holding the fibres together. (It is not quite this bad in practice but it does emphasise what happens if the end is left to its own devices). Butting this against another such end is not easy!

At the left hand end, I'd painted some Heldite around the outer surface and sides of the of the 4010 at the cutting point. To avoid any risking of the 4010 sticking to the rod, I left the inside rubbing surface clean.

I considered Heldite as opposed to Evo-stik because it is good at withstanding high temperatures and oil (used to assist pushing it home in the stuffing box). Although it takes a while to dry, it soaks into the 4010 like a glue and holds the fibres together.

As the photo shows, at the left end where the 4010 has been cut, the Heldite seems have held the fibres together effectively. Now to do it for real...