RMG Issues

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RMG Issues

Postby Rick West » Wed Aug 14, 2013 1:59 pm

The generally reliable SmartWinch has reared it ugly head that will be a regatta killer. It is a control limits failure to the gearing system.

Please note on the Mystic scorecard that Jack Baldwin and I withdrew from the event; I was not able to sail Sunday and fell to 15th. Jack withdrew on Saturday and ended with 18th. Both of us lost proper sensing for control of the programming limits of the winch.

The cause at the moment is traced to the potentiometer (the small red barrel that connects to the gearing at the front of the winch. This pot reads the gear settings and report the positioning to the mini computer that holds your settings. The shaft on the pot to the little pilot gear can and now is known to slip. When it does the winch will become erratic and mostly likely will exceed programmed limits. When the computer recognizes a loss of programming performance, it will communicate with a single beep every 15 seconds (about).

In my case it broke two winch lines and ruined the spindle on the dual Pekebe block at the end of the boom on the system board. I have never seen this before or heard this single beep nor heard of this failure. My winch is the 280DL and has been in operation since 2007 and is the winch shown on the building site when the first SB was assembled.

I turned this over to Dave Ramos at CPM and he reported the findings. He has burnished the shaft and applied CA over the scored area. He will also be advising Rob Guyatt of this issue so some information from him is certain to be received.

If this matter has occurred in the past and was reported, I miss it. So, here it is.
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Re: RMG Issues

Postby Capt. Flak » Wed Aug 14, 2013 4:32 pm

Sorry for your misfortune at Mystic. This is a good report on a possible issue for others. It looks like the repair is simple enough. Let us know how the repair works and if it lasts. Thanks.
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Re: RMG Issues

Postby Rick West » Wed Aug 14, 2013 5:32 pm

Research by CPM show that the first 280DLs had press on gear to the pot shaft. There was splitting and loosening of the gear to the shaft. I never heard this information. Rob then for the later 280DL made the gear and shaft one piece.

When I get back to Annapolis I will inspect the shaft connection to the gear on my 280DL against that of the newer ELs Dave has in stock. It should be revealing.

My suggestion: If you are serious competitor and doing this for a while, inspect the shaft and gear connection. If it shows that it is two piece, carefully see if the gear will come off. If so, thoroughly clean the shaft and hub of the gear, use emery paper on the shaft, then put on a drop of CA and quickly re-install the gear.

Note that I have not done this myself yet. I am on the boat for the summer but will check my stock when back in the shop.

Do this and save some grief and a lost weekend. You sail well by sailing fast with good judgement. You will score badly if you do not tend to the details.
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Re: RMG Issues

Postby tag1945 » Thu Aug 15, 2013 2:46 am

Rick

This is a known issue. I have personally made this repair on several DL winches over the last couple of years. The securing of the pot gear fix, takes care of the problem.

If you can turn the pot shaft while holding the gear, you need to do this repair.

Most of the winches I repaired had far to much lubricant on the gears! I suspect that the over lubricating of the gears is a cause for this problem. The gears need to be kept clean and require very little lubricant, if any! Spray lubricants are a big problem as they are very thin and can , over time, work there way between the gear and pot shaft.

Here is the lubrication instruction from the RMG DL manual:

Try to keep gears clean. Greasing is not necessary. Grease will only
attract grit which can damage the gears and will make the winch very
noisy.
Tom Germer
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Re: RMG Issues

Postby Rick West » Fri Aug 16, 2013 12:31 am

Tom, I know you have done some good work. Issues that effect the operation of our boats and the fun that we have with them is part of the resource 12 discussions was created for. I read everything and just search for this on the forum and found none. I now know two people that have heard of this and not shared it with the network. so, this is now documented for the class and our subscribers beyond the class. It will also be part of the new Building Site, albeit for a 10 year old winch model. In the 12 years I have used the RMG I have not had a failure attributed to the winch. I considered it quite reliable and still do.
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Re: RMG Issues

Postby Frandito » Mon Nov 04, 2013 8:57 pm

This exact thing just happened to one of the boats in the Sun City fleet.
Lots of internal damage
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Re: RMG Issues

Postby Chuck Luscomb » Tue Nov 12, 2013 7:17 pm

Reporting on Jack Baldwins boat...

There was some internal damage to to the sheeting system but that was about it. I built it with a forward bulkhead and a turning block. The RMG line tube locked in the Pekebe in the fwd bulkhead and then pulled the cleat off the port side of the hull. Pretty powerful little bugger.

Found the RMG with the usual shiny Potentiometer shaft and was able to burnish it with 320 grit wet dry paper. Wiped it and the gear with alcohol and reassembled them using some super thin CA (make sure it is fresh glue). Once it set, I repaired the damage done to the RMG Line and sheeting system. The boat was sailed most recently at the Thundermug Regatta in September. There were no issues with the boat or the sheeting system after two days of sailing.
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re: RMG Issues

Postby bigfoot55 » Thu Mar 17, 2016 9:50 am

Update March 2016
2007 Vintage 280DL which has had heavy use. A couple of motor replacements. No other issues until last week.
Full in sheeting position (end point) changed.
Noted after restarting the winch to sail in the first heat, full in sheeting position had changed from pre-race tune. A too tight main was noticed. Readjusting the sheets fixed the relationship until it shifted again. No other damage or issue, just oversheet when started up.

Germer applied the roughed up Pot shaft and CS fix as posted above in 2013.
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