Recent content by Owl

Key point with any kind of plastic windows is the thermal expansion and contraction. When I did my Jaguar 21 windows - about 1m long I think - I calculated that the expansion would be around 10mm over the likely temperature range in the UK. Holes round the fixings and penny washers are the easy...

I'd have a look for a firm specialising in non-destructive testing in your area and ask them. Dye penetrant used to be the standard cheap testing method but I'm not up to date.

I suspect the reason for the lack of towing is cooking the battery. For a non-towing car the limits are well defined - high acceleration gets you to the legal limit in x amount of time so no time for heat build up. As long as the car is designed to handle 70mph into a headwind indefinitely then...

Did Day Skipper with them about 5 years ago. Had an excellent time and learned loads. Recommended.

I've got a Wanderer with the original outboard bracket - one of those that puts the outboard well back from the transom so it clears the rudder. It amuses me because the outboard bracket is thick aluminium and very heavy, but the GRP it is attached to is very thin and flexible. Apart from the...

Memory foam is very slow to bounce back; normal foam bounces back immediately. I'm not sure why memory foam behaves this way - maybe because the holes between bubbles are very small restricting air flow. Not had a good experience with memory foam beds - had a couple; the second was Tempur &...

One way to reduce costs is change to a junk rig - can be far cheaper than the conventional rig. The major disadvantage is the resale value of the boat, but given that isn't relevant then worth considering. Other advantages - besides cost - are much easier handling, ease of repair, lower rig...

https://midsummerenergy.co.uk/buy/agm-batteries/victron-agm-super-cycle-100ah-battery Saw these the other day. Not tried but tempted - 300 recharge cycles from absolutely flat means you've got double the normal capacity in an emergency. Anyone had any experience?

FWIW I figured that using two attachment points (partners and keel step) means the burried bit of the mast can bend as the mast moves, which limits the stress concentration at the partners. A sleeve would result in no flex below partners and a big stress concentration in the mast. This is just...

Depends on the boat and how you use it. Most of the load in a stayed mast is the compressive load of the stays. For the boat, the mast is being pushed through the bottom and the chainplates are being pulled off the deck. Get rid of the stays and you lose most of the stress. The mast needs to...

You need about 10% bury of the mast in the boat - so at least 1 1/2 foot. Preferably more. I don't think it matters how you fit it as long as fittings are strong enough. At 4.5" diameter the mast is probably sufficient in diameter as-is so I'd try it and see. Don't go out in F6 first time -...

My favourite pottering boat I've tried on holidays (Neilson) is a small cat: in light winds one can snooze on the trampoline while steering with the toes, while in higher winds it will get up and go.

Depends on the type of sail. Old designs (junk, gaff etc) were designed when materials were not particularly strong - junks started out with grass matting - so polytarp will be fine. Modern designs tend to rely on tension in the sail cloth to minimise twist in the sail and keep the shape...

There was a PBO liferaft test where one of the rafts failed to inflate - March 2014; Waypoint Offshore ORC - where the connection to the firing pin broke. I was disconcerted that this wasn't seen as a huge issue - the Waypoint was their favoured raft. I've also heard of a cruise ship training...

The key point is to allow for expansion / contraction. If you don't then something will break - probably the sealant but if screws have been used then the plastic will break. If sealant is used then either you go for something like butyl tape which never sets, or use a bead of sealant /...