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Old Sep 24, 2007, 11:19 AM
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HH, Philip,
Re-reading some of my previous replies, I apologize for my undiplomatic comments regarding the rudder play problem.
It does seem though, that if you can actually see wear on the splined shaft that acts as a pinion, given the gear ratio used, there can be huge rudder play with even minimal wear.
From the pics, it looks like the splined shaft has 8-10 teeth - let's say 10.
It looks like the aluminum gear has perhaps 80 teeth. That's an 8:1 downward ratio, not a good thing in this application. Consider that you are attemping to move the rudder shaft only a total of 6o deg (+/- 30 deg from center). That's only 1/6 of a full revolution. The driver gear is then moving only 1/8th of 1/6th of a rev, or 8 degrees. All the wear is occuring on very few teeth. It seems that the level of achievable precision of rudder throw would be very low, even with precise tolerance gearing. Any visible wear on the pinion or slop in the shaft alignments would be greatly magnified as free play in the rudder.
My opinion, perhaps worth only tuppence, is to focus not on repair, but to rebuild the system with sector gearing, a reworked drive train to provide less heavy load on few teeth, and to provide more precise rudder control. I do think there is room to do this.
Perhaps I'm not interpreting the pics correctly.
Thanks,
Dan
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Old Sep 25, 2007, 11:43 PM
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Palo Alto, California
Joined Dec 2006
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Rudder gearing

Dan L - Thank you for your keen observations. You are of course quite right in your recommendation of a more evenly proportioned gear train as a superior option. In trying to keep costs down and accessibility up I chose to use a contrivance of off-the-shelf components that I could squeeze into the ridiculously constricted space rather than opt for cut-down gears.
Based on our prototype (and there were quite a few initial rudder servo gear iterations) I judged the force on the gear teeth satisfactorily low to allow of a reasonable (a hundred or so hours of sailing) service life. If our prototype currently showed signs of wear after all her sailing or had a sloppy rudder I would be the first person to advocate re-designing the gear train and to heck with the expense. This is not the case.
Of course I am extrapolating from a sample size of one, so I am eager to understand Hoghappy's problem more completely and provide a solution.
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Old Sep 26, 2007, 09:17 AM
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Philip,
As I continue to build and work on your wonderful model of the brig, I have commented about many modifications, etc. In no way do I mean my comments on the brig or the Prince rudder as a "product complaint". These are absolutely superior products and I am extremely happy to have one of them.
My suggestions are intended to be iterations, experiments and perhaps "generation two" features on an elegantly designed product rather than criticism, though I see in retrospect how they certainly could be interpreted that way. I am, gasp, an R&D scientist, who of course can't leave anything alone without questioning and tweaking it's design.
My apologies for any overly critical comments.
Bottom line, these models are highly recommended and absolutely superior products.
Thanks again for providing them!
DanL
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Old Sep 26, 2007, 09:18 AM
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I pulled the rudder assembly again. It is exactly as Philip suggested…I have a crack in the weak spot (both sides) where the rudder shaft attaches to the assembly. This is contributing to my problem, but not the entire problem. It cracked due to the stress placed on the weakest point in the design and I’m sure I weakened it some more due to my having to file some of the assembly away to get it to fit. It needed to fit deep enough to allow the rudder tube to protrude through the stern to allow the rudder shaft through the tube. I filed the hull all I could but still had to weaken the assembly by filing it a little too. Perhaps if the assembly were made of a stronger material (nylon ?) or if I were not having to modify it to fit, this would not of become an issue. Looks like I will need a replacement part and will probably need to send the entire assembly to Philip for inspection and whatever it needs. I don’t think thin CA will stick or wick because of all the Vaseline that has been soaked up by the assembly block (see it in the pics).

After thinking on this… it makes sense to me that the tacking problem (trying to tack to starboard) would be affected by the inability of the rudder to stay firmly in position due to it flexing under pressure. This turn to starboard was the hardest tack to complete.

Philip…can the assembly be strengthened at the weak spot …maybe braced on the sides? Maybe hardened?

Philip...I agree with Dan...please do not construe this as a complaint... rather as a test bed for a hard on the product consumer....me!

I love the ship!

Please PM/email me.

Thanks

Robert……….arrrrrrrrrrrrgh….I mean Capt. Slick
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Old Sep 26, 2007, 05:34 PM
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Capt. S, I am glad you finally found the problem. Hard as removal and replacement are, I imagine they are perhaps a little easier tasks than re-rigging everything, as I had suggested *smiles*.
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Old Sep 27, 2007, 10:55 PM
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New ideas

Dan L and Hoghappy - I understand that your ideas are intended as helpful suggestions and they often are just that, allowing me to improve the design, the plans and/or the instructions. For example, the fracture that you, Hoghappy, have experienced in your rudder servo block has made me decide to change the material that they will be made from (moving to PVC).
I learn from all the feedback on these threads, not just about the ships, but about the ways in which my work is subtly restructured to suit many differing personalities.
I am providing a product that stands quite alone in the marketplace. I need to consider the design of our ships from many, many angles. The right solution is a complex balance of serviceability, costs, durability, ease of construction, component availability, and scale integrity, to name just a few of the elements.
Again, I welcome input of all sorts and certainly have no wish to curtail your comments!
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Old Sep 28, 2007, 02:42 PM
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Thanks, Philip. Love your openness and approach. The interaction and exchange is a great part of the SC&H shipbuilding experience.
Dan
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Old Oct 06, 2007, 11:18 AM
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Prince sailing

new pics of the prince !
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Old Oct 06, 2007, 12:33 PM
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Gearld K - very nice looking schooner! If you want to improve performance, attaching the luff to the mast would help. I found that 0.032 stainless steel safety wire (from the airport mechanics) works well. I can bend a 2 circle mast hoop by hand around a former then slip them over the mast. It has to be 2 circles otherwise the luff line will slip out of the gap of a 1 circle hoop. A long luff line "sews" the sail to the hoops. At your scale, you could individually attach each hoop to the luff, which would be more realistic.

Or if you want to form the hoops in place (I needed to do that on the lower part of the jigger mast because I would have had to remove all the fittings to slide them on), then 0.020 ss wire is soft enough. 0.032 might be ok to form around your masts because your masts are thicker and stiffer than mine. I cut the wire to size, sand the ends to remove the burr, then pre-form the first 180 deg on a former, finishing by hand bending the wire around the mast.
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Old Oct 09, 2007, 07:59 AM
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Gerald...

Great to see another schooner sailing the seas! Another alternative to the mast hoops is the way I went after a lot of research and consideration and that is with jack stays. You can use these and still be able to change out sails easily, have good looks and get rid of the luff. For pictures and more on this visit my web site on the build up photo and build up page.

www.princedeneufchatel.com

This is from that site:

7/9/2005...I have researched to find out what method to use to lash the gaff sails to their masts. It seems most likely they were lashed to rope hoops as these were introduced at the begining of the 19th century. Wood (ash) hoops were introduced around 1820, a few years after this ship met her end. Since I can't come up with a way to reproduce rope hoops, I am going to try lashing the gaff sails to "rope jack stays" (trysail mast) with hanks (see the jibs and this link) abaft of the masts. I'm not sure if this is going to be period correct, as research indicates jackstays came into use in the 19th century, but it will solve the problem of being able to easily remove the sails as they will slide on and off the unhookable stays, and they will hopefully look a lot better than they do now....stay tuned.

Update on my ship...

I received a replacement rudder block and replaced all the old assembly parts into it.

Thanks Philip for the free timely replacement!

I soaked it with thin CA around the weak spot this time. I rotated the gears to new contact patches and it tightened up the slop to almost nonexistent. I reduced my almost 2” of side to side rudder slop with close to 3/4”total movement. It is now reinstalled and ready to sail hopefully this next weekend along with the also repaired yacht which I had to replace the rudder servo and straighten the rudder shaft after knocking it over.

Capt. Slick
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Old Oct 09, 2007, 03:41 PM
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Capt. Slick, I read your linked source for the jackstays. Do you have the "right hand page" with the illustrations Monfeld references? I have nothing against jackstays, btw.

I do think hoops would be appropriate, though: Harland, pg 37, "About mid century (1750) the mizzen course was replaced by a small mizzen sail, laced and hooped to the mast...."
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Old Oct 10, 2007, 07:06 AM
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Hey Brooks...

...you mean page 44? There is a page number at the top right of the page and some green arrows to click on, to go forward or back, above and to the left of the page numbers.

http://www.all-model.com/wolfram/PAGE44.html

Hoops would be great but we can't just lift the masts out whenever we want to change a sail (unless the hoops come off without removing the mast or the sails detatch from the hoops easily). With the jackstay, you can just slide the sail hanks on and off to change the sails. If you look closely you can see the bottom of the jackstay is attached to an open brass eye. All I have to do is rotate it 180 and the jackstay will slide off the eye allowing me to slide the sail hanks on/off. Easy as pie! I would rather of had the hoops for looks but couldn't come up with a workable solution. I went with choice # 9, metal hanks on a rope jackstay.

Capt. Slick
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Old Oct 10, 2007, 09:30 AM
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Thanks Capt. just what I wanted. Diagrams are so much better than text :-).

Re easy removal - nothing will match the ease of your jackstay; like you, I can pull the course jackstay and the sail drops in a jiffy. But, if you lace to the hoops (rather than around the mast) you can get, if you choose, the best of both worlds, namely, relatively easy on/off and the strength/stiffness of hoops too. I use DanL's trick of CA-ing the last 2 inches of the lacing line (polyester carpet thread) to make a "needle". This allows me to lace through holes in the sail and pick up the hoop pretty easily. Since the thread is small diameter, it pulls out easily when I want to drop a sail too.

I would not take Mondfeld's 1820 date for wood hoops too seriously. Unlike today's technologically connected world, where pirates can copy innovation immediately, the spread of new ideas in the 1700's was necessarily slower. By the time a book presented an idea, where a researcher like Mondfeld could find it centuries later, it may actually have been in use for years previously. Also, hoops may have seemed so self-evident that authors did not bother to explain/diagram them. The desire to document technology really only blossomed with universal literacy - up to that point, everything was learned one-on-one, master to apprentice.

Hoop refinement - On the schooner Harvey Gamage, the hoops were connected with a light line on the forward edge. The upper end of the line was attached to the gaff. This line kept the hoops perpendicular to the mast, so they would not angle and jam when the sails were raised.
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Old Oct 10, 2007, 11:20 AM
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Shoot hoops.

Shoot, hoops might be easy. Let me think on it a bit.
For starters, the hoops can be made easily from brass tubing (for light weight and better "hang" characteristics) or with brass rod if weight not an issue.
To make a bunch of uniform hoops fast:
- Get a dowel slightly larger in dia. than the mast to allow the desired ID clearance of the hoop to mast. To get just the right dia. if a standard dia. dowel is not available, wrap a mast dia. dowel with a layer of aluminum sheet (avail in cheap rolls from Home Depot/Lowes etc).
- Wind the brass rod tightly around the dowel with no spacing between wraps. Clamp the starting end and clamp the finish end. With a dremel or an xacto saw, cut a straight line along the top of the coil. You will now have a perfect set of matched diameter split rings.
- The above is easy to do with rod or wire - more difficult with tubing. To do tubing, heat it with a torch as you wrap it - just the right amt of heat will allow you to wrap the mast radius without collapsing the tubing. Perhaps the prototype hoops were flatter in cross section anyway. A flattened cross section might slide on the mast a bit better and might not be very noticeable anyway.
- Open the rings enough to slip around the mast and reform and solder in place. Tip - when opening the rings, don't pull them apart by opening the ring to form a big "C", but open them laterally - twisting the wire rather than deforming the circular shape. If you use tubing, you can use a bit of wire in the ends to join the rings with CA or epoxy and skip the soldering. If solder used, slip a square of the aluminum sheet stock between the mast and hoop to act as a heat shield. The soldering is easy - let me know if you would like more "method" info.
- Now, blacken the hoops in place. I use a Qtip saturated with blacken it solution. I've found that the solution doesn't react at all with Krylon paint that I use. It is basically like water, so I often blacken parts after mounting in place.
- Now - back up. How to easily/quickly attach sail to hoop? I'll test something tonight. May be easy. May or may not require additional step in sequence above. May be a number of connectors on the sail itself.
- Would hoops have been used on an 1805 US brig with fishplates and woldings on a compound mainmast?
Is the above useful info? Don't know if it adds anything, but fun to think about.
(The ring making method is courtesy of Spiderchain Jewelry - online supplier of jewelry hoops/rings, etc. It works really slick)
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Old Oct 10, 2007, 03:24 PM
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DanL - in the "jewelry findings" department, say at Michaels or at a beading store, the rings you describe making are called "jump rings"...don't know why. "Split rings", to the findings people, are the ones that you use to hold your keys, namely a continuous loop of metal with the joint only opening with that twisting/sliding motion we've all used to add a key to the ring. Split rings (small diameters can be found in findings) work better on my models since the thread can't escape. Your solder or epoxy closed jump rings would work just as well and might look better because they would not have the multiple passes of a split ring, or the 2 circle rings like I made for the barque.

I've also heard of using paper to make rings. Multiple layers of paper, glue-soaked, are wound around a mandrel to gain thickness, and then sliced to make individual rings. If they were coated in something to resist water, like paint or glue, they would be suitable for a sailing model, I think. They might look more like the real wood rings I have seen on schooners as they would have square edges.

On the Endeavour we used wooden hanks to hold the luff of the jib to the stay. They were raw wood strips, bent in a shape like the top 3/4 of an 8. The strips were wrapped around the stay, then the crossover joint was seized to the jib. The strips were notched at the crossover so that they laid fair on the stay. If you let the jib slat, they would break, so we tried not to free the windward sheet when tacking until we were sure there would be wind to fill the jib on the new tack.
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