The Ship Model Forum

lookin great Tarsier!

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Hi tasier Good move. Follow the path of the least resistance. I have been in similar situations were decisions have to be made that would compromise accuracy. Unfortunately these things happen. I've never yet come across a 100% accurate model , there is no such thing.
Dave Wooley

No problem. The drives still look trick. They were not moved far enough to look out of place. Besides I dont think anyone will knowtice when the model is in the water or at sail.

TommyL.

Looking great. I wouldn't have noticed if you hadn't pointed it out, even along side the photos of the 1:1 scale version.

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Hi Guys -

Good weekend out at the beach but now back to work. I epoxied in the intakes for the jet drives - pretty messy. I used Marine epoxy PC-11

http://www.pcepoxy.com/pastepoxies/pastepc11.asp

here is a picture of the finished product:

forgot to log on first - it was me - Tarsier

Usually if its a development post, I think its obvious who forgot to log in...

No trouble on that...

Hmm, coming along nicely tarsier...

Not sure how you got the impression that people aren't interested in this thread! This by far is the best I have seen, on ANY modelling group so far, bar none!

Just out of curiousity, what influenced you to chose this as the subject? I like the look of this boat very much.

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INS Veer: 1/100 scale, under construction!

Thanks kalkurap-

I was just trolling the internet for a new project and saw the boat and just fell in love. I think that modeling can be pretty frustrating so you have to pick a subject you just love in order to keep the momentum going. If it were something boring or ugly (beauty is in the eye of the beholder) I couldn't get motivated to work on it. I also wanted something that I could do in a large scale - the model is in 1/20. My previous model was in 1/50 and I wanted something where I could do more detail.

The work on many of the 1/72 or 1/96 boats just amazes me but I haven't worked that small and I don't know that I would enjoy it as much.

The next project I have started planning out will also be a 1/20 scale boat - a converted fishing "long liner"

I am going to be going on vacation soon so my progress and postings will slow down considerably until after Labor Day.

Tarsier.

Well - not quite after labor day but we tried to beat the traffic and come back a day early - didn't get much done tonight but was able to watch a little tennis and lay out the plan for the electronics:

The two circles on the top are the layout for the transmitter below on the left is the electrical layout for the motors, to the right is the layout for the servos which will just about be on top of the motors. The water cooling tubes for the motors and the ESC's were not drawn it. At the bottom is the RX - as most of the radio controls, the Spektrum is designed for planes and helicopters.



Does anyone have a good way to mount monster sized motors? I was going to use some blocks of wood with metal straps and U bolts - figured this would keep them from breaking loose - any suggestions would be appreciated.

Tarsier

Hi Tarsier Motors can be mounted in a number of ways.
If you have plenty of room I prefere to mount the
motors on a strong metal plate with the motors bolted
into the face of the plate. Have a look at Picture Post on
the method used on my Mersey. This method is good for
any size of motor. Also I do use block and strap, which
also works well . for this insert strips of rubber between
the straps and the motor case which helps to maintain a
good grip. Hope this helps

Dave Wooley

Hey guys -

Back to the motor mounts. These are pretty big 900 vs the standard 500 or 550 - they need to move at 15,000 rpm which sounds pretty fast to me - I don't know what a 500's rpm is.

I can use a metal bracket - the problem is that I would have to attach it to something. I don't know how good of a bond I would get if I epoxy the metal directly to the bottom of the hull - on my last boat, I epoxied wood blocks, then screwed the motor mount into the wood - this held up pretty well. I could buy resin or fiberglass mounts which would probably bond much better but I am skeptical that they would hold- here are two I could buy:





What I would rather do is epoxy wood blocks to the hull - then screw in brackets to the wood - I would use hanger bolts and then nuts on top - probably top them off with a little loc-tite - here is a "mock up" I plan to use two rather than one "U" bracket but I got the wrong size for one so I only had three:




It is just a rough "mock up" - I would need to bend the brackets and trim them a little to get them to fit nicely. I would also need to shape the bottoms of the wood blocks to fit better to the hull. Also, I plan to add metal straps to the top to hold the motors down. I bought a silicone oven mitt which is rated to 675 degrees so that should keep things in place.

Things appear to line up from the top but then there is a problem - the motors are up too high relative to the jet drive shafts:



I could move the motors toward the bow to reduce the slope of the angle and using couplers will solve the remaining angle. There will be more resistance than if it was straight.

I think I need to leave a little room for air to circulate - my worst fear is the thing heats up and bursts into flames in the middle of the pond!

Any thoughts? Comments? Suggestions?

Thanks,

Tarsier

Hi tarsier I forgot to mention that the threaded bolts in the picture shown are very much part of the motor mount, in so much that they are adjustable to conform with the round in the bildge and any other slopes in the lower parts of the hull and when correctly adjusted are bonded into place. As for the RPM on your motors It seems rather high even for a water jet system, the average conventional drive is very much slower . On My 1:96 Tirpitz each motor revolved up to 1100 rpm using three 45mm props on 12 volts which at full throttle was slightly over scale speed.
Dave Wooley

More Help Needed

Hi guys:

Was walking down the aisle of home depot hoping for inspiration to hit. I was looking for a more elegant solution. I think I might of found one - here are pictures below:




I don't know what the things are called but it was very cheap. There is a clamp like thing which can hold the motor and a base which is held to the clamp with a bolt. The plan is to use some loctite to secure the bolt, clamp and base and then epoxy the assembly to the fiberglass hull.



As you can see, it doesn't line up straight but that is what flex shaft if for



So the question is: WHAT SHOULD I DO? To that end - what can you use to bond Metal to Fiberglass? Epoxy?

Thanks,

Tarsier

Not sure if it can be done. You could opening its pours by roughing the metal to get a good bond, or encase the whole base of the backet in resin.

Just some ideas. Please think about it and wait for more input. Weight the pros and cons. I would feel like complete poo if you moved on what ideas I brought and messed up your hull.

TommyL.

thanks for the input Tommy - I'll wait for some more people to weigh in - the more opinions the better!

Hi Tarsier Resin and matt are the materials that will give a good firm bond around the base of the engine mounting with a GRP hull. I also use bondo { a car body filler ] .
Dave Wooley

I use a real simple motor mount; I take a piece of schedule 40 PVC pipe, whose ID is close to my motor. Cut a peice about an inch long, and sand part flat- the flat part is where I mount it- using epoxy- to the hull. I drill and tap a hole through the PVC for a screw- sized appropriate for the motor- to hold the motor in place. I've used this system on many boats with great success- BUT- I've never tried it with 900 series motors.

Something like this;

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Sean Hert

I think Sean's idea was the right one. I went and got some 2 inch pvc pipe - cut out some motor supports, I then used some epoxy to set the rings in place. Here they are:





The motors fit pretty snuggly and the width of the pvc is the same as the watercooling tubes so it fits perfectly. The next step is to sand or file down a flat on the joining bracket and then mount with epoxy. I also need to tap some holes for set screws to insure it stays in place. It should line up much better as it will sit much lower than the other solutions.

Sean's solution is much more simple and much more elegant. Half the fun of scratch building is figuring this type of stuff out.

Tarsier.

That's way cool! Glad I could help!

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Sean Hert