I was up and at it good and early continuing the tedious and arm aching job of stripping the hull back to a good surface
A mate turned up unexpectedly with a set of hydraulic gear pullers but they wouldn't quite fit. However, we reckon that with shorter legs and the rudder removed they may work so he's bringing them back in Saturday for another try
I took a break from antifoul removal to dig a hole under the rudder. I reckoned by eye we'd need about a foot more to get it off, we'll see in due course how good my eye is!
Then it was back to another bout of stripping. I'm developing the most time and energy efficient technique as I go along
This is a close up of the problem I'm dealing with...
That's a typical area before I start on it. Just the pressure wash off when she was lifted out has left a patch that is right down to the thin layer of sound epoxy, probably a single coat of Gelshield or similar, surrounded by the thick layer of blue (I suspect) badly applied epoxy overlaid with several layers of old antifoul
The technique as it stands is to attack an area with the 100 bar pressure washer on needle jet setting. It's not quick but it removes most of the old antifoul and quite a bit of the unsound epoxy at no cost and with minimal effort
Stage two is to attack any remaining antifoul with a tungsten carbide scraper. That takes some effort but it rapidly cleans back to the failed epoxy and softer patches of that come off too
That leaves the harder areas of epoxy largely untouched. However, I've found that Nitromors paint stripper will soften it quite effectively (suggesting that perhaps it isn't epoxy after all or that it was badly mixed or applied in the wrong conditions).
It takes two applications of stripper, the second about ten minutes after the first. Then give it twenty minutes or so and a good thickness can be peeled off with a 4" steel scraper
Stubborn and really thick areas may take two or three goes to clean back. After that, a thorough pressure wash, leave it to dry off and it's ready for sanding
A thorough going over with 40 grit on the big sander leaves a decently flat surface ready for finishing
The waiting between bouts of stripping and sanding was not idle time
It proved surprisingly easy to remove the rudder quadrant. At which point I discovered that the rudder now moved easily with no stiffness at all. This suggests that the very stiff and heavy helm is not down to worn rudder bushes as we'd assumed (I'll inspect the bushes and may replace them anyway as they're not overly expensive)
So it must be either the rudder cables or the autohelm motor drive that's causing the problem. More investigation, and probably more money, required
Back to the plot..
The next step after removing the quadrant was to undo and remove the single bolt that secures the collar to the top of the rudder post. This proved straightforward too once I knocked a wedge in to take the weight of the rudder off the collar
All I had to do then was knock the wedge out and the rudder dropped the half an inch or so onto the blocks I'd placed ready
When more hands are available we'll remove the rudder completely and inspect the bushes and seal
Another ten hour plus day and by the end of it I really needed a shower. So off I traipsed to the facilities. A lot cleaner and much refreshed, I treated myself to a curry and a couple of pints in the pub
Whilst quaffing I checked my emails and a helpful email from the tech guy at the prop manufacturers advised that they sell or rent out a suitable puller for the Featherstream prop. If the plan for Saturday doesn't work that's the next option
Tomorrow I may take a break from stripping. Glen is down for the weekend and I think we'll tackle some of the engineering works while he's here.
A mate turned up unexpectedly with a set of hydraulic gear pullers but they wouldn't quite fit. However, we reckon that with shorter legs and the rudder removed they may work so he's bringing them back in Saturday for another try
I took a break from antifoul removal to dig a hole under the rudder. I reckoned by eye we'd need about a foot more to get it off, we'll see in due course how good my eye is!
Then it was back to another bout of stripping. I'm developing the most time and energy efficient technique as I go along
This is a close up of the problem I'm dealing with...
That's a typical area before I start on it. Just the pressure wash off when she was lifted out has left a patch that is right down to the thin layer of sound epoxy, probably a single coat of Gelshield or similar, surrounded by the thick layer of blue (I suspect) badly applied epoxy overlaid with several layers of old antifoul
The technique as it stands is to attack an area with the 100 bar pressure washer on needle jet setting. It's not quick but it removes most of the old antifoul and quite a bit of the unsound epoxy at no cost and with minimal effort
Stage two is to attack any remaining antifoul with a tungsten carbide scraper. That takes some effort but it rapidly cleans back to the failed epoxy and softer patches of that come off too
That leaves the harder areas of epoxy largely untouched. However, I've found that Nitromors paint stripper will soften it quite effectively (suggesting that perhaps it isn't epoxy after all or that it was badly mixed or applied in the wrong conditions).
It takes two applications of stripper, the second about ten minutes after the first. Then give it twenty minutes or so and a good thickness can be peeled off with a 4" steel scraper
Stubborn and really thick areas may take two or three goes to clean back. After that, a thorough pressure wash, leave it to dry off and it's ready for sanding
A thorough going over with 40 grit on the big sander leaves a decently flat surface ready for finishing
The waiting between bouts of stripping and sanding was not idle time
It proved surprisingly easy to remove the rudder quadrant. At which point I discovered that the rudder now moved easily with no stiffness at all. This suggests that the very stiff and heavy helm is not down to worn rudder bushes as we'd assumed (I'll inspect the bushes and may replace them anyway as they're not overly expensive)
So it must be either the rudder cables or the autohelm motor drive that's causing the problem. More investigation, and probably more money, required
Back to the plot..
The next step after removing the quadrant was to undo and remove the single bolt that secures the collar to the top of the rudder post. This proved straightforward too once I knocked a wedge in to take the weight of the rudder off the collar
All I had to do then was knock the wedge out and the rudder dropped the half an inch or so onto the blocks I'd placed ready
When more hands are available we'll remove the rudder completely and inspect the bushes and seal
Another ten hour plus day and by the end of it I really needed a shower. So off I traipsed to the facilities. A lot cleaner and much refreshed, I treated myself to a curry and a couple of pints in the pub
Whilst quaffing I checked my emails and a helpful email from the tech guy at the prop manufacturers advised that they sell or rent out a suitable puller for the Featherstream prop. If the plan for Saturday doesn't work that's the next option
Tomorrow I may take a break from stripping. Glen is down for the weekend and I think we'll tackle some of the engineering works while he's here.
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