Drum Winch vs Sail Arm - Pro/Con?

[Ben Diss]

I'm going to replace the Ozmun servo that's in my boat with something else this winter. It's got a bit of corrosion on it so I'm a bit distrustful of it. I've thought about the RMG drum, but I'm leaning towards the new Hitec 5995 servo. I've got a Hitec programmer so I could slow it down if needed.

What the pros and cons of winch vs. sail arm? What should I be considering between the two?

Thanks.

-Ben

[s vernon]

I think you should consider whether this servo with 333 inoz of torque and 180 degrees of arm rotation has enough power to trim an EC12. 5995 a little over 2 ounces weight. Ozmun about 8 ounces. 5995 a little over $100. RMG about one and a half times the price and a bit heavier. RMG 280D 156 inoz.

Something just does not sound right. If this servo really can trim an EC12, you can bet there will be a stampede.

You cannot directly compare an arm winch with a drum winch based on torque numbers. I built a 2 3/4 turn drum winch based on the 42 in oz S148. It easily trimmed a US1M. The S148 servo with an arm couldn't even trim a Victoria in a bit of breeze. I watched one die. Same servo, same torque as before, but able to do a great deal more work as a drum winch.

Scott

[Ben Diss]

I have this servo in use in an airplane and it does indeed deliver the power. Powered at 7.2V it will deliver 400 oz in.

Other than power and resolution, are there other factors to consider?

-Ben

[Ken S]

Ben, from what I've been told, the big issue to consider is arm length. The servos are rated in inch pounds...so at one inch out from the center of the servo shaft you get the 400 rating...at 2 inches you're down to 200 at three you're down to 100 and so on. With a drum you're dealing with a constant torque as the line winds on/off at pretty much the same distance from the center of the servo shaft.

Ken

[philair]

From my experience the RMG is the way to go, power/torque requirements aside. I recently got a new boat with an Ozmun which I have been able to compare to the RMG in my older 12. The RMG is faster, gives finer adjustments, and allows concentrating on the sailing without having to anticipate how long it will take for the winch to do the job. Rounding marks is where you get killed with a slow winch. The Ozmun is headed for the spares bin as soon as I can afford a new RMG.

[Larry Ludwig]

RMG is without a doubt the finest winch made today. The Futaba drum winch (5801) is the only other one I would consider using. I have been using one in a test boat for 4-5 months now and have no complaints. It does not have all the settings offered by the RMG, but it is $35.00 less.

[Rick West]

The RMG is the best there is when all the points are mentioned, Ben. The 280DL with the brand new 30mmZ drum is to date the finest winch in features, quality and customer service of anything out there that haul all the sheets in at the leeward mark. The unit has more resolution ability that is possible with stick movement on todays TX. The processor is sealed, programmable reliable and will talk to you. Read the calibration checklist on the building site for how it communicates. It is comforting when you turn it on in the morning and beeps once to say that all is well and everything you have programmed is current. I use the winch in three classes over the last six years and never had one fail and only lost one program when I left it on all night and the battery died. I would buy nothing else at half the price.

The class has always liked it and then came the DL. Then we were in love and using the 26mmSDS drum that was asked for and made specifically for us. Rob Guyatt took the Thoresen tapered 5.5 turn drum that cost $45 and designed the 30mmZ for 7.2 turns for $15. I check my mailbox everyday waiting for the first of these. This setup will not put you in the top ten in the country but it will sure make you the best you can be in sheetline control.



...94

[greerdr]

As usual the class Sec is on the money.The RMG is a joy to use and unlike him I have deprogrammed mine WAY too many timesbut reprogram at lakeside is a snap.I too am anixously awaiting my step down drum.Go RMG,be happy.

R.C.Greer