Krick U25: Refit and Restoration Log 2019-09-11

[QuarterMaster]

The latest addition to the Fleet. The venerable Krick U25. A very simple, 3 channel Dynamic diving RC Submarine that is fun to use!! I had one which was in fact my first boat back in the late '80s.

You can actually read an article about the loss of her, “Grey Lady Down; A Users Perspective” The SubCommittee Report, Issue 26, September 1996. Pg 41. I learned a lot that sad day.

After restoration and refit with some modifications to insure survivability, and compatibility with modern running gear, she'll be a perfect go-to fun boat at the pond for myself, inexperienced people who wish to try, and children that may become future RC Submarine enthusiast's. The best way to bring people into this hobby is to join a local RC boating club, and hand someone the transmitter. Dave M. and Bob M. have no issue doing just that. I plan to run a “Subschool” with anyone at my local group who is interested.

Her keel was laid by no other than by Jim Butt of Subcommittee fame, and I got her from Joe Oliver at this past 2019 Groton SubFunRun.


First things first…..strip her down….clean her up!!!

[trout]

Ed, this will be a great WIP. I think your idea of a sub school submarine is a great idea.

[He Who Shall Not Be Named]

I second that. And if any non-qual's get out of line ……...… grease 'em!

David

[QuarterMaster]

Despite the fact we've been running boats every weekend since Groton, and I find myself overjoyed on how well SSN-591 has been running, I've been finding the time to work on U25.

She's been stripped of operating gear and all that grease the former owners felt to use since apparent failure of her push-rod seals, which was revealed upon cleaning.

I also ripped out the old style "grease gun" stuffing box's, which will be replaced by my home brew dual cup seals shaft seals. That means I'm tossing the original 1.96mm shafts with L/H, R/H molded in plastic props. On order from the Prop Shop UK are two brass replacements that will use a 1/8" SS shaft (P/N V3011/3 BRZ scale props handed pair). The new Shaft tubes will only be increased by 1/32" in diameter.

As you can see it took a wee bit of "surgery" to remove them. We may differ in our definition of "wee". You know what they say about egg's and omelet's. One should never be afraid to proceed!

ANYTHING can be fixed.



All the electronics, both motors, both batteries will be replaced. New lid as well as lid sealing system will be used.

I'm printing 3D printing the new motor mount as I write this, I'll update in a few days. Now back to PROTEUS.

Nice little winter project that will fill the gaps when I'm not working on the other boats.

[steenv]

Hi, I have just aquired the same uboat . have you worked more on your build - am interested in the 3d motor mounts that you wrote you would be working on

[QuarterMaster]

Hi, I have just aquired the same uboat . have you worked more on your build - am interested in the 3d motor mounts that you wrote you would be working on

I will be returning to the project shortly. Stay tuned. I'll hand over any 3D files as well.

[redboat219]

Ed,
will your refit include provisions for static diving?

Here's a refit on the same boat by David Welch using rotary servo outputs for the dive planes and rudder.

[Das Boot]

I like Ed’s strategy. Get out the BFH and go to work.

[QuarterMaster]

I like Ed’s strategy. Get out the BFH and go to work.

I torched those friggen' stuffing boxes with a propane plumbers torch and they didn't budge! The heat should have softened the epoxy enough to slide them right out. Whatever Jim Butt used to fix them in with should be used by SpaceX to coat the hull of STARSHIP for re-entry! It took the BFH to get them out lol! (And a 3/8" drill!!)

No worries! Came out great in the end with the new double, cup ring seal!


Here are both shafts, shaft seals, and new brass propellers in a 3D Printed jig to maintain alignment, FWIW, the originals were not only out of alignment with the boat, but with themselves! I believe the angle from horizontal per the plans, and what the original motor mount indicated, is about 7.5 deg. Now it lines up perfectly with the canted motors. I did give them a slight "toe-in" angle to insure I clear the new, realistic rudder, and themselves with respect to the motor c/l-motor c/l distance.



No H2o getting past this!



Time to sand, and sand.....(JB Water Weld)



More coming soon.

Ed