Cutty Sark RC - Page 2 - RC Groups
Thread Tools
May 18, 2013, 03:35 PM
Damp and Dizzy member
Brooks's Avatar
Hi Norgale, missed your recent posts. The easiest way to make a prop shaft for a sailboat is to use brass rod in a brass tube. Use K&S brass tubes and rods, available at a hardware. Two diameters of brass tube are needed: 1 with a slip fit on the shaft (ie ID 3/32") and one the next size larger (slip fit on the 1st brass tube). The stuffing box is comprized of the larger tube, full length from motor to prop, plus 2 short pieces of the smaller tube epoxied into the ends of the long tube; these short pieces make the bearings for the shaft. The bearings are greased or oiled, the shaft is inserted, and you are good to go. Don't fill the tube with grease, however - the friction of trying to turn a long shaft in grease will be too great for your motor. Only a small amount of grease is needed on each bearing for waterproofing. This is the drive shaft for Machdog's Steam tramp and it works well. I think I learned the method from Umi_Ryuzuki. She's the expert. You can use 2 thicknesses of bearing material (thus requiring 3 tubes) if you wish. This provides less friction tween the rod and outer tube if you have a long shaft, but your length would, I'd say, be ok with the 2 tube construction. Ask Umi to be sure (Scale boats forum usually).

Brass rod is more easily threaded than steel rod. Brass will be plenty strong enough for your sailboat. If you google "taps for 3/32 rod" you will get charts and info on what you need.
Last edited by Brooks; May 18, 2013 at 03:59 PM.
Sign up now
to remove ads between posts
May 18, 2013, 04:02 PM
Damp and Dizzy member
Brooks's Avatar
My sailboats are usually overweight, and I believe most guys building from a static kit find the same. I may have misunderstood you, but it sounded like you were afraid you'd need too much ballast; I'd think it more likely that you'd need to reduce ballast from what you'd like. That reduction is ok wrt heeling, you just make your fin keel deeper. Then, the reduced amount of ballast has a longer lever arm, and is equally effective as what you planned....been there done that :-)
Last edited by Brooks; May 18, 2013 at 04:17 PM.
May 18, 2013, 07:10 PM
Retired for now
Thanks for trying to switch me to "scale sail" Brooks. I forgot that this topic is for sailing and the other is for building. I'm sure my build belongs in scale sail.
I don't understand why I would have to lighten this model when it's going to take a bit of weight to get it to the water line. Even with the lower bulb added this hull is going to ride very high without added weight inside the hull. Without sails it won't even need the bulb hanging down. Pete
May 19, 2013, 03:58 PM
Retired for now
Got the two motors situated and the shaft tubes about right. Need a little more alignment of the shafts and she'll be good. Pete
Name: Cutty Sark RC 001.jpg
Views: 102
Size: 268.2 KB
Description:
May 24, 2013, 12:39 PM
Retired for now
Have some time today to do some more work on the C.S so I've placed the steering servo under the rear cabin so that it will be accessable along with the steering linkage. I'm looking for left and right three bladed brass props but so far I haven't found anything this small. If you know of where such a sized prop can be had I'd appreciate the information.
Next is locating the space for the batteries and other RC stuff 'tween decks. Once all the mods for the RC stuff are made I can then start on the planking and general building of the model. Pete

Last edited by norgale; May 24, 2013 at 12:45 PM.
May 24, 2013, 02:19 PM
Thomas Armstrong

Brass Prop


Quote:
Originally Posted by norgale
I'm looking for left and right three bladed brass props but so far I haven't found anything this small. If you know of where such a sized prop can be had I'd appreciate the information.
Take a look here: http://i.materialise.com/materials

They can do stuff in brass, inox, and lots of other materials. Only thing you need is some spec on some supported format (http://i.materialise.com/creationcorner)
May 24, 2013, 06:53 PM
Retired for now
Good info tarmstro. Interesting how they do that 3D stuff. Thanks for posting this. Pete
May 24, 2013, 07:27 PM
Kraut
pete what diameter should those props have
got some friends that built 1:100 and smaller, they should know.
May 25, 2013, 08:00 AM
Retired for now
Hi Schrott. Good to hear from you again. Hope you had a great winter with plenty of snow to fill up your lake. How's ol' Dumpster doing?
Anyway the prop needs to be about 3/4" across. That's all the room there is before the prop hits the hull. Maybe your friend will know where I can get a left and a right in this size. Pete
May 25, 2013, 03:00 PM
Registered User
Quote:
Originally Posted by norgale
No suggestions hey? SO let me ask this, what sized die do I need to thread a 3/32 steel rod for the shaft? Everything is listed in mm or whole numbers and I do not know what they mean. Anybody???? Pete
Pete
3/32......4-48 die

See attached Starrett guide pic's.
Pete if you can't read from my pic's let me know.
OBW
May 25, 2013, 07:22 PM
I meant to do that....
crashnburned's Avatar
Check here for possible props. 3/4" is around 19 - 20mm

http://www.harbormodels.com/site08/m...nufacturer.htm
May 25, 2013, 10:10 PM
Retired for now
Did some more planking today. This is slow going work but this layer of planks is the balsa base layer. The finish layer is lime wood and will be smoother ---I hope.
Name: Cutty Sark RC 001.jpg
Views: 131
Size: 303.3 KB
Description:

Name: Cutty Sark RC 002.jpg
Views: 95
Size: 277.1 KB
Description:
May 26, 2013, 06:27 AM
Registered User
Pete, will this help?

#1
Simple tool for metric conversions.
http://www.metric-conversions.org/le...illimeters.htm

#2
Having been to Al's store 2 wks. ago,I was amazed at his selection of props. (about a 4' x 6' board with props of all sizes)
Call him or e-mail him,he has more than his web site shows!!!
http://www.shipsnthings.com/indexNS.htm
May 26, 2013, 08:51 AM
Retired for now
The last time I bought two props from Al (1") it cost me $75 and that's just too much for me to spend right now. I'm hoping to find something lower in price even if it's only plastic. Pete


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Sergal Cutty Sark norgale Boats (FS/W) 1 May 14, 2013 09:51 PM
Discussion Cutty Sark tim slocum Dock Talk 19 Feb 02, 2008 09:57 PM
Discussion The Cutty Sark on fire Punkie Dock Talk 27 May 23, 2007 08:17 AM
Discussion Cutty Sark clipper destroyed by fire rcminiman Sailboats 8 May 21, 2007 07:56 PM
Sterling Models Cutty Sark display kit ElectRick Scale Boats 7 Aug 28, 2005 02:05 PM