One of the points raised in the survey was the need for a new propeller - the existing one is badly pitted and I'm told causes some nasty vibrations. As with anything in the marine industry - the choices are endless. However they can be grouped into the following three categories: Fixed, Folding & Feathering.
| Type | Pros | Cons |
| Fixed | Cheap, Simple | Highest relative drag |
| Folding | Lowest drag | Traditionally poor in reverse & less power than feathering |
| Feathering | Best motoring performance both ahead and astern. Reduced "prop walk". | Higher drag than a feathering prop. |
This is a feathering prop made in New Zealand (as if the name wasn't enough of a clue). What makes it a little different from the rest is that the blades are plastic. They supply a spare blade as a part of the package, the intention being that these are sacrificial in the event of an underwater impact. It is pitch adjustable by the user with an Allen key. Whilst it doesn't offer variable pitch in the strictest sense, there is some clever trickery when reversing that makes the blades snap into "optimum" angle of attack.
Bruntons is a UK company and is definitely one of the leaders in the field. The offer the Varifold - a range of 2, 3 & 4 blade folding props and the Autoprop which is a premium feathering prop with variable pitch and a number of other special features. They also offer fixed props and at the boat show were exhibiting standard feathering propellers, but these are not mentioned on the website.
At the London Boat show, Bruntons had a tank with an Autoprop running in it. Every five seconds it would switch between ahead and astern propulsion. Seeing the blades feathering and unfurling for the new direction was really fluid, almost organic in motion. The Autoprop is a truly impressive machine, with only one significant disadvantage - Cost. We were quoted a boat show price of about £1700 for the saildrive model, which is about 70% more than a branded feathering propeller. That being said - I'm absolutely convinced that if I had a motor sailor or planned on lots of motoring I think the cost would be more than justified.
Gori is a Danish company who specialise in low drag folding propellers. Like Bruntons, they have their own magic that sets them apart from the rest. Their folding props are able to unfold differently for ahead and astern as well as providing an "Overdrive" feature which is a different blade profile for fair weather motor-sailing.
They also sell ultra low drag racing propellers, which would be tempting, except I suspect that these are built with sailing performance as being the primary factor, and motoring distant second. If I had a race boat they would definitely be on the list. Speaking of which, Swan mainly use Gori propellers. I feel that they let themselves down in terms of customer interaction. I mailed them for a quote and absolutely zero response two months later. Additionally there was no sign of them at the London boat show (although they do plan to be at Southampton). For the above reasons I can't tell you what these beauties cost.
Volvo Penta These guys represent the safe choice if you're already equipped with a Volvo engine and saildrive. They are obviously a Swedish company. They offer standard 3 & 4 blade folding propellers and represent the vanilla end of the market. I'd suggest that these are probably more appropriate for cruising boats in that they don't offer a 2 blade option for reduced drag that would appeal to the cruiser/racer market. Expect to pay around £700-£800 for a 3 blade folder.
Offering a range of feathering props, which seem to be the Oyster Yachts weapon of choice. Some positive user reports of these across the Internet.
Apparently the Managing Director of Gori left and created this range of propellers, which is claimed to be superior. They also appear to have good links with various boat builders. Interestingly there are relatively few user anecdotes across the net good or bad. After meeting Bruntons at the boat show we decided that we liked them as a brand: Friendly guys on the stand, British company, great products. Our main fear of going for a folding prop was the much fabled poor performance when going astern, but the Bruntons guys explained that with modern folders such as their Varifold, this issue is greatly reduced. This is due to a twisted blade profile - making it more similar to a fixed prop in terms of motoring characteristics. We decided that we valued the low drag of a folder more than the better motoring of a feathering or Autoprop. The same logic applied to 2 blade vs.. 3 blade, so we settled on a 2 blade Varifold. At £740 it was also nearly £1000 cheaper than the Autoprop.
It arrived in the post yesterday. My first comment is that I'd have liked to see a little better packaging. The bottom of the box was sagging from the immense weight of its cargo. When I opened the box it's clearly an exceptionally well engineered product and effortlessly glides between motoring and sailing configuration. 
I’ll post more when we fit and use it.
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