I use the same linkage system in all my boats. The pushrod for my 25'' Hartman Pushboat ( 2'' Robbe nozzle), is 14 5/8'' long, the threaded ends are 4-40 thread, and use 4-40 screws to attach them. The steering arms are Aluminum, and most all of the hardware is 304 SS. If I use 4-40 threaded rod, it is SS. The pushrods are either Brass tubing, or, Carbon Fiber tubing. **The Truckable, uses the new 2-56 x 4-40 threaded end, with the Chromed ball, at the rudder end, as I cannot replace it. The other end, witch would be almost impossible, to replace, is a 3mm H.D. end link designed for 1/8 scale rc cars, and fits the 3mm thread, in the HD Aluminum servo arm. The pushrod is 4-40 SS, sleeved in Carbon Fiber tubing, as I cannot replace it, without cutting a hole in the deck. I have pushrods in boats that are still tight, and are 25 years old. CB

Thanks for the info - I'm going to pass this on to others in our club.
I had hoped that I could take a few days and join your group on Sunday - pick up some building tips and have fun on Sunday- work put another spin on that thought - All the Best, Mike

Originally Posted by CaptCB

I have pushrods in boats that are still tight, and are 25 years old. CB

Yeah, but your boats hardly get any run time...

We figured that "Workhorse", had well in excess of 800hrs on it, but no, they never get run.

Here is what I installed in 1989, and we have better link ends today. CB

I just finished the latest tub test, and the boat passed!!! I do plan on running it at Riverside, with a barge. Nothing like your first POND TEST, to be a Tug Boat Regatta. I am sure there will be plenty of photo's. CB

I am happy to say the boat worked GREAT!! I ran the Navigation Course, light boat (no barge). Then I ran the barge course with a 40'' long barge, that weighed between 35-40 lbs. Boat worked great both times. A lot of people were surprised at what you can do with a 12'' tug. Photo's to follow in a day or so. CB

As I ran the boat on Sunday, it weighed 3lb 14.0oz. That included 16oz of Brass flat bar, as ballast, below the batteries. The batteries were 2, 1700 NiMH packs, and run time seamed good. The change from the 3300's, was to LOWER the center of gravity, and make the boat more stable. CB

Here is the interior layout, and some from the Riverside Regatta. CB

Good pic's .

Mark

+1

looks good Charlie. hoping to get radio gear in tonight or at least this week and get to the indoor test facility maybe this weekend.

Somebody made a copy of your kit. http://www.cornwallmodelboats.co.uk/...AN3048_00.html
And they got a pricetag on it...

Originally Posted by Sharky1dk

Somebody made a copy of your kit. http://www.cornwallmodelboats.co.uk/...AN3048_00.html
And they got a pricetag on it...

Nope, not ours, that one is much bigger...

This photo shows just how much smaller (2/3rds as big), our boat is, compared to a Springer. Model with deck and cabin, is a Springer. CB