Design Details for R/C Square Rigger Operating Systems - Page 8 - RC Groups
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This thread is privately moderated by DanL, who may elect to delete unwanted replies.
Feb 28, 2010, 06:56 PM
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DanL's Avatar
I should have known I was wrong.
Your pics look great. It takes some tuning to get the tacks to move forward, but once the "loop" tension is right, I think the clews will come forward just fine..
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Mar 04, 2010, 08:52 PM
Paratrooper's Avatar

Main and forecourse sails

Shipmates: I finally have the new course sails rigged and ready for another trip to the lake. We plan to go out this weekend because the weather is going to be in the high 60s which is much better for my artritis.

I have abandoned the maincourse tacks. I tried everything I could think of including making new clew lines and a .037 wire in the foot of the sail to get it to come around. I found the only way they would work was if they were completely loose. This was not a problem on the forecourse sail and the sheets and tacks work without binding on the boomkins. When I finally just disconnected the tacks on the maincourse it started working perfectly.

Here are a few photos of the set up as it is now.
May 25, 2010, 07:32 PM
Paratrooper's Avatar

New forecourse and maincourse yard rigging

I experienced two failures of my course yards during the big gunfight. What I had before with tubing and a screw eye to connect to a pair of eyes on the mast was proving to not be up to the task.

After reviewing what Lootenant Dan had on his brig, I came home and reworked both the forecourse and main course yards. I have two different sail set ups for the forecourse, one with the original SC&H design sail and stainless wire as bolt ropes and one with the ability to furl it.

I have three sail set ups for the main course, one that is permanently furled for rough seas, one of the original SC&H design which works the best with winds favorable, and one that I can furl up some for a slightly different appearance.

The new methods of securing the yards to the mast are shown below.
Sep 21, 2010, 10:20 AM
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DanL's Avatar

Rigging Material

Up until now, the only sources I knew for really good looking twisted line for R/C model rigging use were expensive and the lengths too short, or making your own on a ropewalk.
On a recent visit to the Erie Maritime Museum, the modelers working on the scale model brig Niagara were using nylon seine twine for rigging. It was really beautiful looking.
The twine is from Memphis Net and Twine, comes in many diameters and in white and tarred. It's very cheap - a 1-lb spool of a typical diameter is $10 and has 2,000ft of line!
The tarred line is not sticky and doesn't leave stains. The white line can be easily stained with water based wood stain.
The unknowns:
1. Many sizes, but specified by a gauge # that gives no clue to diameter.
I sent a request to Memphis Twine for sizing samples. If they send the samples, I'll write up an accurate diameter table.

2. Beatiful looking, but how much stretch?
I'll measure stretch on the samples relative to my home-made twisted polyester line that has very low stretch. Other nylon twist I tested had a lot of stretch, but this stuff is supposedly low stretch - important for scale operating rigging.

3. How does it work thru operating blocks and how does it drape, etc,
I'll run some tests and post. Supposedly doesn't unravel as easily as
normal twisted line.

If I can get the samlples, are there any other things to test or look at?
This would be a great source of scale line if it works out.
Sep 24, 2010, 06:04 PM
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DanL's Avatar

Twisted Line for Rigging

Measured the diameter of the white twisted seine samples from Memphis Net and Twine. The attachment shows the info and the sizes that can be used at different scales. If your not too picky about exact diameter matches to scale size, a wide range of prototype diameters can be matched with the MN&T diameters. For larger scale models, I need to get more larger diameter line samples and get measurements. For smaller scale models, even the smallest MN&T twine diameter (#3 at 0.5mm) may be too large for running rigging sizes.
I got only a few samples and had to estimate some diameters, but they should be close. What I couldn't estimate was the diameter of the biggest diameter samples in their range of sizes.

I still need to look at how the line drapes and how it runs through blocks. Also need to test the stretch in the one long sample that was sent. The line is smooth, round and firm. Should look great after dyeing and a light waxing. The tarred twine I saw in Erie at the museum looked awesome.

The attachment has applicable diameter info across a number of scales. Hope this is useful.

More later.
Last edited by DanL; Sep 24, 2010 at 06:13 PM.
Sep 24, 2010, 11:35 PM
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Wow, that loks great Dan. See if you can get samples that would go up to 1/12 & 1/10 scale. I am currently making the blocks for my Malabar II schooner which is 1/10 scale & had planned on using .6mm, 1mm & 1.5mm for the running rigging. Wonder what they have close to those sizes?
Sep 25, 2010, 12:11 AM
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Bracing Winch

I have been messing with a concept for a bracing winch that compensates for the geometry and keep the braces taut. Here's a link to s Youtube clip of it.
Homer Bracing Winch (1 min 22 sec)

You might also check out the Yahoo Manned Models group.

Vince Homer
Sep 25, 2010, 12:15 AM
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DanL's Avatar

scale rigging

The top table shows the scales I did sample calculations for.
The bottom scale shows what's available from Memphis.

If you want 0.6, 1.0 and 1.5mm, look at the lower table:

0.6mm would be size #4
1.0mm would be size #7
1.5mm would be size #15 (actually just a bit smaller than 1.5mm)
Sep 25, 2010, 03:24 AM
meatbomber's Avatar
Wow that winch is great clean run, no slack and no extra bungees required in the rigging, seems to be quite an optimal sollution!
Sep 25, 2010, 08:54 AM
1915 Schooner Mariette
delaneyp's Avatar
You can get very neat & compact versions of these types of self-tensioning drums from RMG (along with their brilliant & hugely powerful SmartWinches).

I have 2 of these winch/drum setups in Mariette & they work perfectly on a loop setup with tension taken up in one direction (ie, for pulling in a fore & aft rig).

The drum set consists of 2 drums, one directly on top of the other - the lower one fixed to the winch drive shaft, & the upper one being spring-loaded against the lower one. The idea is to run a line a few turns around the lower fixed drum, then along the hull to a pulley, & back around a few turns on the upper spring-loaded drum (with about 1/2 a turn of spring pre-load).

Whilst RMG recommend that they only be used for a single-direction pull from the fixed drum (as in fore & aft rigs), I think that they would be fine in a "balanced" square-rig bi-directional bracing setup, providing the differential between the brace runs is not more than 1/2 a drum turn.

Might be worth a look ?

Kind Regards,

Peter D.
Sep 25, 2010, 09:45 AM
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DanL's Avatar

Brace tension control

Vince -
Great test device and interesting result.
Peter points out the RMG drums as similar to the drums you made.
I never tested the RMG drums, but when I checked their instructions, they point out that the load must be on the fixed drum. Putting the load on the tensioned drum would likely use up the free rotation, increasing the slack on the unloaded brace rather than decreasing it.
In your test, did you apply any resistance to the rotation to see what happens? The wind can really place a load on the pulling brace. In all the tension relief systems I tried, there had to be equal tensioners on both stbd and port braces.
Your test looks great. Definitely worth looking more into this whole approach to see what happens under load conditions.
Jerry Todd also has some interesting approaches that include very prototypical location of the braces on the pinrails. Your drum design would be great for that approach.
Again, a nice design - another step closer to getting the "perfect" system someday.
Sep 25, 2010, 11:20 PM
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DanL's Avatar

Brace tension compensation

Vince's post got me thinking again about the whole topic of compensating for differential brace tension as yards rotate.
Jerry and others have posted a lot about this.
Here's what I may try installing this winter to simplify the Syren brace rigging.
Re-mounting the servos laterally on slide rods and tensioning the lateral movement with heavy, adjustable bungee would allow all compensation at the servo/winch drums. The system would be self-centering and easily adjustable. The bungee could be adjusted easily, unlike using springs that would have to be sized pretty closely for length and tension.
Will have to try a mock-up soon.
Sep 27, 2010, 12:15 AM
Registered User

Homer Brace Winch

I did try the winch with extr load on the pulling brace and as you might expect when the pulling brace is the one on the drum fixed to the shaft there's no effect. Wen the load is on the drum connected by the spring there is a little slacking in the offside brace. The amount depends on how much pre-rotation of the spring you start with. The limit to pre-rotation is dtermined by the amount of tension your yards can tolerate without overstressing everything. The diference in brace ension due to wind must be taken up by the spring pre-rotation tension. If that's not enough the spring loaded drum will lag a little putting more tension on the brace.

With a very stiff yard/mast setup, I don't think this would be a problem. In a true scale model the yrads probably wouldn't take much brace pre-tension without bending.

Once agian, this is all theory other than the mock-up in the video. You guys are the experts.

Vince Homer
Sep 27, 2010, 09:13 AM
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DanL's Avatar

Brace offset and tension

From what you desribe, there could be another factor. When the tension is at a high level, either when the yards are squared, or, from your test description, when the spring tension is set high, the servos have to work pretty hard. That shortens battery run time and combined with higher winds, could really eat up battery capacity.
Again, all just thoughts that need to be tested.
Sep 28, 2010, 08:24 AM
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tghsmith's Avatar
could this be where the spiral pullies that RGM sells might work instead?(or an eliptical or eccentric pully) a pair stacked oposite of each other, thinking that a simple adjustable mockup of a yard could be made to figure the pull lenghts required...
Last edited by tghsmith; Sep 28, 2010 at 09:33 AM.

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