The Autumn Projects Begin.

[Smoggy]

So me old plague ship is out of the water languishing at Greenway (Loddon) for some off season jobs, it needs a survey for the insurance by next summer and bss and I'd rather not be lifting during summer season so may as well be now, lurking beide is the company van I borroed for the weekend (very handy).

One of my projects while it's out is to see about converting from the old leaky stuffing boxes to dripless shaft seals (lip seals) but not a lot of space so needs a bit of engineering, have to remove props/shafts/glands before I can even see what I've got to start with.

One festery old sterngland.

Props came off easy enough with the borrowed hydraulic puller from work, first nightmare was trying to knock a double roll pin (it's actuall a roll pin within a roll pin) out of the port shaft coupling, no sodding chance,it's splayed out and the cheap mickey mouse punches from toolstation just peen over and wedge down the middle (avoid anything with the minotaur label) and leave me even more stuffed, after much swearing and stress gave up and removed the starboard shaft with no trouble.

Roll pin of doom!

Tried drilling the pin with cobalt drills but just took the edge off straight away as the pins are damned hard.

Removed starboard gland to work out a possible solution to the seal conversion , I have a plan... (a cunning and devious plan no less) and went home sulking and sobbing about the roll pins, current thinking is if the pins won't budge I have to take a cutting disk to either shaft or coupling (coupling is £150, shaft is £625, guess which gets the chop), back next weekend and the shaft is coming out one way or another! (I'm bringing lots of cutting gear and disks and some rubber welding mats/wet towels to keep the grinding dust out of the grp)

Back at work the removed gland cleaned up nicely.

After a chat with Andy at Clemments engineering I came to the conclusion the starboard shaft is work out and needs replacing and my ideas to modify the gland are not as irrational as I thought they may have been, idea is to maching down down outer bearing end to a 58mm stub (still leaves 3.5mm wall thickness) to take lip seal and fit in back to front with old stuffing box facing outward, the props exit in a tunnel so shouldn't affect drag at all.

 

[Smoggy]

Lip seal arrived today so finished removing cutless bearing from inside and bead blasted to clean so I had a good enough surface to clock up with a dial gauge, set it up on the mill and had a go.

Had to run the mill backwards and grind a flat on the back of the cutter and put it in backwards so I could work inwards instead of outwards as the boring head is supposed to work.

Started on the tip and measured to check it was going properly centred before going too far.

Seemed fine so went for it.

Fits nice! I left a 12mm stub at original size as it goes through 10mm of grp and will locate better.

 

Next step is to drill and tap for a couple of grub screws to hold the new half bearing secure inside, grub screws will be under the seal in the clamp area probably at 10 o'clock and 2 o'clock so they can be accessed without having to remove the whole casting from the hull.

New cutless bearings will ordered for both glands and P brackets, would be daft to not replace while doing this much work.

Will offer up to the hull at the weekend and keep my fingers crossed, at least it can be put back to regular stuffing box if it all goes wrong.

[MargeandParge]

You do what you do really well Smoggy. 

Kindest Regards Marge and Parge