Roberts Spray 36. Too slow?

Any idea of the maximum rpm of the prop. What max engine rpm and gear ratio have you got to the prop?

That puny little thing is designed for much more easily driven hulls. Even clean the performance will be poor. A little fouling will kill it. I expect you will be hard pressed to get it to absorb more than 10kW on that hull. Maybe motor/sailing you could extract more out of it.

Sailing close inshore around any headland on the NSW coast can be a test of endurance in a boat limited to about 6kts. If it is only 4kts you need to get further offshore but it will still be slow if you are going against the set.

I once competed in a club race many years ago. The club commodore had a Roberts 36 with bilge keels. His wife preferred to crew on an International 24 cat in the fleet. On this particular day the race was around an island located 10nm from the harbour and back in. She finished the race on the cat before the Roberts cleared the harbour. It could not make much better than 90 degrees to the true wind.

Some sailing boats are made to sail, some are motor/sailors and some bob around reasonably well without making much progress.

However anything less than 6kts in a 36ft boat is poor and, like others have stated, there is likely a lot of sea life being carried around.

Rick W

 

In Australia keep an eye out for Adams boats. Some examples:
http://www.boatsales.com.au/used/adams/35/

No idea of what your price range is but 35ft is reasonable for coastal hops.

Rick W

 

haha. Trust me I am aware. I motor sailed a Piver 31 from Lake Macquarie to Yamba over Xmas. (my mates other boat). We were lucky to get one days usable wind. Mostly it was Northerlys. The onboard 20hp diesel was capable of 7K, but it broke down one day into the trip and we had to use the 9.9 outboard. The noise drove me mad and so did the 4-5K water speed. We kept away from headlands and even out a bit we still felt like we barely moved. So after this we don't want another slugger.


Rick those Adams look like a nice Yacht. What sort of performance would you expect of out of this type under sail and power?

 

Dennis
Adams had a tendency to design boats that sailed well. I got very close to buying a plastic Adams 13m with the dagger board but I moved jobs and address that did not have the same access to water.

I had a work colleague in Brisbane a bit over 10 years ago who sold a Farr11 to trade for a 42ft Adams steel and he felt that was a vastly more capable boat for cruising than the Farr. The only thing in common though was the price. You need to know or know someone who knows what to look for in any used boat but probably more so with steel. He was very pleased with what he got. He goat a lot of value for the price. Much less than it would cost to build.

I expect the 35ft Adams would get in a groove at 6 to 7kts under sail. Depending on engine size you might get over 7kts if you were not concerned about the fuel usage.

I am sure you will find owners who have covered similar territory to where you are.

There is also Herman Boro who designed aluminium and steel yachts in WA. I spent time talking to him before I bought my first yacht in the 70s and he swayed me toward a medium displacement fin keel rather than a heavy displacement boat with full keel. Here is one of his:
http://boatpoint.ninemsn.com.au/boats-for-sale/details.aspx?R=2723379

He was prolific at the time and popular in the west. So another one to look for but not sure if you will find many on the east coast.

My interest in these boats is really dated now so there may be others around but then most modern designers for little yachts are working with plastic.

I would be wary of buying a boat that was modified from the original design without the designers input. This was the problem with the Roberts 36 I referred to earlier.

Rick

 

BERTIE's prop

The BERTIE's prop is controllable pitch, so can be adjusted to the load so the horsepower goes into the water where it belongs, instead of being optimised for one narrow rev range. Many years ago I was shipmates with a wooden lapstrake SPRAY on a 1000 mile trip to windward. It was used as a motor fishing boat and was a full power vessel. It had a GMC 3-71 of at least 100 hp which took up most of the cabin. It wouldn't go much over 6 knots but boy would it buck into the weather!! We were caught out off of Cape Mendocino in a horrible gale that lasted 2 days and lost all electrical power but the diesel kept running and we made it in OK.

 

With being named Bert and having built and sailed a 38' bruce roberts spray I feel I should add my experience. Using my experience as a steel fabricator I made several alterations to the design; 1. the draft was increased by 10" along the whole of the keel. 2. The deck was raised to meet the hull top therefore creating no rust traps. 3. The hull was raised off the frames by lifting the chine bars by 1/4". 4. Not an intentional change but the boat came in at 16 tonne.
The rig is a bermudian ketch but over the years we have increased the sailing speed by swapping second hand sailings around. To get "Rita" going we need to increase the sail area. Two of us can handle "Rita" quite easily and she can keep the full sail plan up to F5. We are planning to add a yankee with a pivoting bow split when we next visit the boat. To confirm we can only motor 6kn but can sail a little better. Rita will never win any races but we have had some long periods of cruising in northern Europe. With being 11.5m LOA we stay under the 12m range but have plenty of space to live in. The comments made on this type of hull gave me food for thought and came up with that a faster boat could have been made but what I have experienced the choice was justified.