March 2015 MAINE COASTAL NEWS Page 5. Not Just Fabrication, But Propellers Too!
TRENTON – Many times we get compla- cent with the mechanical things we use. For boaters, especially power, there are a lot of things that can go wrong if you do not keep with the regular maintenance. For most, the engine gets the attention it needs, but what about the propeller hiding under the stern? An annual check-up may prevent a situation from occurring at the worst possible time. There are a few propeller people along the coast. Some used to use pitch blocks to get the blades into the desired position. There are still some that only use this meth- od, but most have gone high-tech and the results are worth the added cost. Nautilus Marine Fabrication in Trenton has long been known for the fi ne fabrication work and a number of years ago they added propeller work to their business. Jim Patten, one of the owners of Nautilus, said, “I don’t know really what started it all other than feedback from Mark Dickinson and know- ing that Essex had fi nally breathed their last breath. We know there was no other propeller shop in this area so that sparked our interest. We talked about what technol- ogy was available other than the traditional pitch blocks. Knowing that the boat industry had evolved as far as more horsepower, the propeller had to be fi ner tuned than what they were years ago. We bought our fi rst MRI in ‘04, and two of our employees went to school at Hale Propeller. That is where we started.” With everything running on computers much of the guess work has been eliminated. When engines are sea trialed the propeller better by the correct one because the engine will not perform as it should. It is all about performance, and Jim added, “The commer- cial guys are the worst. They are using them the most. One of the biggest problems we see is when guys do not put zincs on their boats and they aren’t bonded correctly. Before you know it the propeller is gone or well on its way. Sometimes when it ends up here it can’t be welded on because the metal is at a stage where it is not weldable. Lots of times there are cavitation problems that do not get corrected. We have learned over the years how to correct a lot of that stuff and that will save a guy his $4,000 propeller from being eaten up in a couple of years.”
The biggest aspect of any propeller shop is being able to use a MRI. “An MRI reads the blade, is really the best way to describe it,” said Jim. “It scans it with a probe and tells you what angle that blade is, if it is out or not, the pitch and other things that go along with reconditioning a propeller. I guess the greatest part about the MRI is its closeness for tolerance. I am not really sure how close the tolerances were with pitch blocks years ago, but I am sure they are not like they are
now. We will tweak them to make a propel- ler do exactly what it needs to. That is a big advantage. The other advantage of the MRI is that if a guy comes in, and we recondition his wheel, all that information is stored in a database. So if something happens and his propeller gets totally annihilate, we either rebuild it or get him a new one. And we know exactly what that propeller needs to be.” All the shaping is still done by hand. There can be a lot tweaking before all the blades are within the tolerances needed for each other. It can be quite time consuming, but the end result is the best. On the average wheel you can be anywhere from four to six hours for a standard recon. Usually what it ends up being is that it looks pretty good, but it needed a little bit of welding on one blade. Well you’ll end up welding on one blade, well that weld will pull that blade. Then you have to tweak that blade back to where it was before.”
When a propeller is done right there are no returns and that is how Nautilus wants it. Jim said, “We try to do the fi nest job that we can. We have set our standards high, and thus we have few returns. If it does come back, we fi x it.”
For those that do their own mainte- nance, do not forget your propeller. Jim said, “You should defi nitely have it inspect- ed every year especially if you’re using it commercially. That way we get the chance to run it through the propeller shop. We look inside the hub to make sure there are no stress cracks. You also want it balanced. That way you can see which blade is the heavy one and on those we end up sanding a little bit off the back side until all blades are the same.”
Those that take lobster boat racing seri- ously know full well the advantages of hav- ing a propeller tuned. Racers are constantly looking for an advantage and one way is to make sure that the propeller is giving you everything it can. Jim said, “They are always trying to get that little extra bite. Adding cup is one of the things that you can do. Some believe they have got to have a cup whether the system calls for it or not.”
Some of the other things they do is to check the bore to make sure that it is con- necting properly to the shaft. Sometimes if you have a vibration, it may not be the wheel. It may be key bound and not sitting on the shaft just perfectly.
Jim said, “Like I said, there is a little more to it than just twisting your blades to get them to do what you want them to do. We stamp every wheel every time that yo u bring it in. We know when you brought it and what we did to it. That is a big plus.” Jim has been pleasantly surprised by their success in servicing propellers. It is
A view of the propeller shop at Nautilus Marine in Trenton.
A before and after photograph of a damaged propeller looking new when done.
now a major portion of their business. Jim added, “I didn’t really know what to expect. You never really know what to expect when you go into a new business. I take the most pride in it because that is something that we started on our own and just hoped to hell that we made it.”
Well they certainly have been success- ful and they are constantly expanding the work space needed. Propellers are not cheap, and with the amount of investment you want to make sure that it will not become a prob- lem so if you have not had your propeller inspected, now is the time to call.
Bring your boat to New England’s most capable yacht yard for the care she deserves. Repairs, refi ts, storage and dockage available for vessels up to 200 feet and 480 tons.
Belfast,Maine 207-930-3740
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31