1/12 remote minehunting vehicle build

[Albion]

Digs? There's a right side and a wrong side to get out if the bed

[He Who Shall Not Be Named]

I'm sorry, I'm the guy who got this thread off-topic. I should have kept my smart-ass remarks to myself. Sorry about the pig-pile I started there, Darrin. Otherwise, I'm very much enjoying this mine-hunting model Darrin has come up with.

So, guy's: please keep the comments focused on Darrin's build.

Thanks.

M

[ffr2608]

Rennshape rails in for the hull join pins. Built the trolley catch in brass.

[ffr2608]

Started to build the snorkel base. CF helicopter blade is the perfect fit and will keep the topsides as light as possible. Plan to do light detailing up top to simulate the real deal.

[ffr2608]

Since the Nacken is on hold, I decided to get the hull to sea trial condition. Everything is blocked in and sanded to an acceptable level for testing. Blending the carbon helo blade to the base was a real treat and I would not wish that on anyone. Still more tuning on it. Caps for the detachable sonar are done. Most ballast lead will be inside it. Time to move on to the 2.75" endcaps and place an order to McMaster Carr.

[MFR1964]

Darrin,

I always like strange boats, your build is looking excellent, how do you want to steer her?, are you going to use a V tail mixer?


Manfred.

[ffr2608]

Thanks for the nice comments...Yes, V tail mixing. Fins are linked together by side but turn in different directions. Did some pull tests in the pool and seemed to work very well.

[ffr2608]

Here are 2 shots showing an exaggerated right turn. The front fins are trying to create a left roll are the rear are counteracting it with a right roll. Turns will be tight, even with the throws reduced to 25 degrees or so. I'm not planning on hot rodding this thing so the low lead should keep everything level if the boat is driven relatively scale.

[ffr2608]

Started building the WTC for this thing. The goal is to have a running boat by the San Francisco regatta in 5 weeks. Endcap is reversed on this one. Bow cap holds the rack and the stern is separate. I really wanted to have the linkages short and easy to access. Dumas dogbone is held in place by a bit of silicone so it mates up at the rear when the endcap is slid on. 55 turn integy direct should be plenty for the impeller. Wish I had more room for a reduction.

[greenman407]

If not, they make more winds for those Crawlers. I think I have seen up to an 85

[ffr2608]

Got the WTC assembled and did a float test. As I was starting to suspect, The upper snorkel is too heavy and there is not enough reserve buoyancy to add weight in the keel. I am almost too heavy to even successfully run the boat. BUMMER......

Solution: I am going to make this the fictional MKII version that is electric only with no snorkel. It actually looks better without it and I have way too much time to scrap the build. Will probably do a stubby sail with a couple antennas coming out of it. Side note, the prop and appendages work great.

[greenman407]

Are you sure that there isnt some room to squeeze some foam in somewhere, like between the WTC and upper skin? How about a smaller, lighter battery? Is the snorkel hollow or solid? Increase the length of your WTC. Once you get more buoyancy add a small amount of weight to the tips of your lower control surfaces to offset the weight of your snorkel. If its hollow , seal it up real good so no water gets in. If its solid, can you make it hollow? Reduce weight where you can. How about those heavy brass pushrod seals? Can they be replaced with plastic ones?

[ffr2608]

Every open space has foam in it and I am just about neutral with very little ballast in the keel. For now, I will run it with a shortened mast. The long mast is carbon and very light. To effectively build this boat, I would double the size and really pay attention to where the weight goes. I'm guessing the actual boat used a stabilization system to keep it level. Especially on the surface. It looks like it's going to run really well with the adjusted mast.


D

[ffr2608]

Got the paint all sorted out. Went with some light chipping to reduce the appearance of future scratches. I also fabbed up a temporary antenna bracket. Looks OK for now. We'll see If I ever do the long one again. I also like the contrasting color of the towed array.Time for sea trials.

DH

[greenman407]

Looks like a probe from some science fiction movie.