Sherman DD
#51
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RE: Sherman DD
Here are some pictures of the Lift and Turn bracket I designed for this thing. It has been doing exactly what I thought it would do, fight me every step of the way. I do believe I have it licked now though.
Herman
Herman
#52
RE: Sherman DD
How many RPM's and how many AMPS have you figured will be necessary to propel this "anchor shaped" boat through the water Herman? Are there bearings there in the outdrive system? Hope so.
~ Jeff
~ Jeff
#53
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RE: Sherman DD
Bushings only. The bearings are in the stuffing boxes. I am still going to have to get with my local electronic guru on the amps, but the RPM's will be the same as the tracks, proportional.
Herman
Herman
#54
RE: Sherman DD
Well, I'm sure it will need to be "proportional", but the amp load and RPM need to be significant to launch this thing.
I raced electric boats and your weight to drag ratio is staggering, to say the least.
Just curious, that's all.
~ Jeff
I raced electric boats and your weight to drag ratio is staggering, to say the least.
Just curious, that's all.
~ Jeff
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RE: Sherman DD
Yes, but all I need it to do is to move while in the water. The real ones only did 5 or 6 knots in a calm sea. I will be happy as long as it makes some forward progress in the water! On land the propeller motors will have no load on them, while in the water the tracks will have a minor load from the suspension and weight of the tracks, which is minimal. The only time that they both will have a load on them is entering and exiting the water.
Herman
Herman
#56
RE: Sherman DD
Where is the water-line going to be? How much of the propeller is going to be submerged and even, what size and pitch are they? You don't want the props to cause any cavitation by one, too fast an RPM, too small in size and not deep enough in the water.
Just some food for thought. I had a few boats I built that had those problems to overcome and let me tell you, it would have been easier to buy an RTR but I stuck with it and had the fastest boats on the water using very few battery time. I owed it all to this ugly mechanical speed controller that cost about $100 but was the cream of the crop in SC's!
~ Jeff
Just some food for thought. I had a few boats I built that had those problems to overcome and let me tell you, it would have been easier to buy an RTR but I stuck with it and had the fastest boats on the water using very few battery time. I owed it all to this ugly mechanical speed controller that cost about $100 but was the cream of the crop in SC's!
~ Jeff
#57
RE: Sherman DD
Here's a pretty cool video of it. You might want to turn down the volume on this.
http://vimeo.com/32361410
~ Jeff
http://vimeo.com/32361410
~ Jeff
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RE: Sherman DD
I have seen that before, and it is a really cool video. Not sure where the water line is going to end up. I know I am going to have to add ballast to get it down anywhere near the normal waterline. My props are 1.5 in. dia. and will be completely submerged, they are normally used on slower vessels. I started out with boats too. I only have 4 at the moment. 1/32 S-100 schnellboot, 1/35 Revell PT, 1/12 PBR, and a Springer tug. The S-100 has working torpedoes and 3 brushless motors, the PT has been converted to a mid war boat, the PBR has brushless powered water jets, and the Springer is the stand by rescue boat.
Herman
Herman
#59
RE: Sherman DD
ORIGINAL: Green Amphibian
Here are some pictures of the Lift and Turn bracket I designed for this thing. It has been doing exactly what I thought it would do, fight me every step of the way. I do believe I have it licked now though.
Herman
Here are some pictures of the Lift and Turn bracket I designed for this thing. It has been doing exactly what I thought it would do, fight me every step of the way. I do believe I have it licked now though.
Herman
I keep looking at the photos of the metal drive mechanism that you have built and I am amazed with that device. Incredible! I sometimes have trouble gluing two pieces of plastic together and would never have attempted that. Wow.....uhhhh, I mean WOW!
Rex[X(]
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RE: Sherman DD
ORIGINAL: Green Amphibian
I have seen that before, and it is a really cool video. Not sure where the water line is going to end up. I know I am going to have to add ballast to get it down anywhere near the normal waterline. My props are 1.5 in. dia. and will be completely submerged, they are normally used on slower vessels. I started out with boats too. I only have 4 at the moment. 1/32 S-100 schnellboot, 1/35 Revell PT, 1/12 PBR, and a Springer tug. The S-100 has working torpedoes and 3 brushless motors, the PT has been converted to a mid war boat, the PBR has brushless powered water jets, and the Springer is the stand by rescue boat.
Herman
I have seen that before, and it is a really cool video. Not sure where the water line is going to end up. I know I am going to have to add ballast to get it down anywhere near the normal waterline. My props are 1.5 in. dia. and will be completely submerged, they are normally used on slower vessels. I started out with boats too. I only have 4 at the moment. 1/32 S-100 schnellboot, 1/35 Revell PT, 1/12 PBR, and a Springer tug. The S-100 has working torpedoes and 3 brushless motors, the PT has been converted to a mid war boat, the PBR has brushless powered water jets, and the Springer is the stand by rescue boat.
Herman
Cool, I have the Italeri 1/35 scale S-100 S boat. I'll have to keep you in mind when I get around to building it. I too would like to have operating torpedos, or at least operating torpedo doors. I also have the Linburg PT 109 that still needs to be built. Kinda getting back into boats. I built the Robbe PT 15 about 28 years ago ( still have it, but it needs an overhaul ).
I would love to see some pics of your boats. Send me a PM an I'll send my email address. Don't mean to hijack the thread guys sorry.
Jim
#63
RE: Sherman DD
Really? Bump to the top? []
No new pics? Gesh.
~ Jeff
No new pics? Gesh.
~ Jeff
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RE: Sherman DD
Yes, PM sent.
I have been working on lights, light guards, and some track sections while waiting on some other things. I will post pictures later today.
Herman
I have been working on lights, light guards, and some track sections while waiting on some other things. I will post pictures later today.
Herman
#66
RE: Sherman DD
#67
RE: Sherman DD
And Herman, what other parts are ya needin' or waiting on? I know how that list can get expensive... FAST!
I may have some extra Sherman parts that are on yer list there that you don't need to buy.
Just askin'.
~ Jeff
I may have some extra Sherman parts that are on yer list there that you don't need to buy.
Just askin'.
~ Jeff
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I have the second control board now, still have to put it in. I am intermittently working on the hoops that hold the screen up now. I have a few other things on the bench right now also that I need to finish.
Herman
Herman