Starting 1/8 scale T5 build, need critique of my proposed setup

[Speed810]

Nic...

Use something sharp to mark the hole. I don't think a center punch will do it. You can even use he head of a 16D nail you might have sitting around. You'll be surprised that it will make a nice small start indent in the glass. Then drill that with say a 1/16 or 3/32 bit then drill it out to the size you need. If I'm between bits (say it was a metric bolt) I would rather drill to the small side and file the hole slightly until the bolt fits in smooth. I don't like there to be a lot of slop in the hole especially on a boat where your wanting everything sealed up. (Of course your going to use a marine sealant when permanently mounting the rudder and/or strut)

Mike

[nichismo]

actually don't even own a center punch I usually just take one of the smaller drill bit and pound it 5 times or so with a hammer, but ive never worked with anything even remotely close to being as unorthodox as this. I need to find a way to secure it without damaging the hull, especially working on the transom.

I'm actually going to mount the motor and ESC assembly in virtually identical fashion to how you did yours, I really liked your approach as its both simple to craft and will be strong and easily positioned when securing. I'm just going to have to drill holes in the rails as it appears my mount doesn't have any.

I also forgot to ask earlier in how I can easily fashion the grease fitting/inlet. id rather purchase something like one of the brackets or oiler blocks here on OSE but they seem to be always sold out of the 5/16 sized ones. Id rather not solder a smaller piece of brass tubing straight onto the main tubing.

[Speed810]

Hey Nic...

I'm going to go with Phil on the mounting of the motor. Actually you could go two ways that would be plenty strong. Looking at the tub area and as Phil had pointed out it appears the boat has a reinforced foam core where the motor mount is placed and where the stuffing tube will go down through the hull. As Phil suggested is to cut slots through the top glass coating into the foam core the length of the rails. I would drill a series of 3/16 holes in the rails so when you epoxy the rails into the slots you will have a stronger bond. You could also add some 3/16 or 1/4 sq birch stock on each side of the slots for more bonding area to the rails.

My particular installation was taking a piece of 1/8" ply cut to the width and length of the rails. I then cut small maple blocks and positioned/epoxied them at each hole/slot in the rail. There are 3 on each side. Now this is where you could decide to permanently mount the rails to the assembly with epoxy and glass cloth or if you want to be able to remove the mount down the line as I did...You can bolt the rails to the blocks. I opted to use brass inserts threaded for 6/32 cap screws. The blocks were center drilled first to 3/32 to center the holes and then drilled out to accept the inserts. The inserts were epoxied and twisted into each block. The blocks and ply platform were then covered in glass cloth and thinned epoxy. After the assembly had cured it was then centered on the boat centerline and epoxied in place.

The drive line stuffing tube was then installed. As others had suggested I used an 11/32 log tube which makes it easier to remove the 5/16 stuffing tube if it became damaged etc. I also used the OSE 11/32 shaft tube sealer/oiler. The 5/16 stuffing tube protrudes through the 11/32 about 1/4", but allows the sealer to seat right up against the 11/32 perfectly.

Hope this helps


Mike

[nichismo]

Ok, I'm just a little worried about making a clean cut in the hull for the rails and not going too deep, my rotary tool is pretty cheap, I wish I had an actual dremel.

When you mention the wood stocks to add to the rails, do you mean they would sit down inside the slot ?

So you recommend against your method for my particular hull, is this because of the belly pan I have or the foam core inside? Or both

[Speed810]

Ok, I'm just a little worried about making a clean cut in the hull for the rails and not going too deep, my rotary tool is pretty cheap, I wish I had an actual dremel.

When you mention the wood stocks to add to the rails, do you mean they would sit down inside the slot ?

So you recommend against your method for my particular hull, is this because of the belly pan I have or the foam core inside? Or both

I'm thinking with a little work and patience's you could use a razor saw to cut through that top layer of glass. I don't think its probably that thick. I think it might be difficult to cut with any dremel just because of where you need to make the cuts. The birch sq. stock would be epoxied on the outside edge of each slot. So instead of gluing into say an 1/8" deep slot you add say 1/4" to that by using some 1/4" sq birch.

No...I'm not saying not to use my method...It is your choice and either will work...Just my method may be a little bit more work intensive. I just chose this method because I wanted to have the option to remove the whole mount in case I wanted to try a different motor....etc.


Hatch work Sketch:

[nichismo]

Phil, when you mention in your instructions, "green" and "red" finishing pads, what are these? im confused as to whether these are sanding blocks or applicator /foam pads of some sort?

id like to start prep to the hull while im installing hardware and such so that its ready to paint as soon as I have all the components accommodated. I also need to do a little light sanding to the back transom, as I noticed when trying to test mount the rudder bracket that its not yet level enough.

[Speed810]

I believe Phil is referring to scuffing finishing pads. 3M makes a lot of different abrasive pads for scuffing and buffing hard finishes....fiberglass, plastic, metals....I use them on my bowling balls to give them different finishes based on the lane conditions....LOL

If they are the same pads I'm thinking of they are like 6" X 6" colored pads about 3/16 to 1/4" thick...They almost look like a pot scouring pad. The different colors are designating different abrasive qualities. Lowes or Home Depot have them. Not sure about Walmart and places like that. These would work great on the fiberglass hull to prep it for prime and paint.

[Luck as a Constant]

Yup.
3m red pads are for prepping for primer.
The gray pads are for paint prep.
The gold are for scuffing things like raw plastic. They are the least abrasive


Sent from my iPhone using Tapatalk

[Speed810]

Nic,

Here is a close up of the motor mount plate I made for my HRC mount.

[nichismo]

Thanks so much speed, that's extremely helpful. USPS tracking although very unreliable states that the amount will be here on Monday. Once it Does I'm Going To Take A Day Off From Work and go to town on this boat! I've decided I'm just going to model it after the 2000 miss bus as its intended. Going to call Mr McKnight at TBG and hopefully get an order in. I also spoke with Steve at RCBC about a stabilizer kit and canard brackets.

which epoxy do you guys recommend I purchase? Just JB weld? Should I get a quicker settling or focus on strength, or perhaps I'll just get a few. I need to make a trip to home Depot or hobby lobby and purchase all the supplies I need.

Also, Speed, when you said you got a better bend in your brass shaft tubing by hand, did you heat it up at all? Or just use pure force?

[Agitator]

The only epoxy I use is West systems with 205 hardener. I get mine from Aircraft Spruce-best price and fast shipping. Order the pump set for it as well. What have you planned out for a water-tight box to seal up the batteries, motor, radio, etc?

[phil t]

Screwing that motor mount to the wood blocks looks like the best way, you can take the whole mount out if needed to.
You can use some light grit sandpaper to prep the hull for primer, 120 be ok. You will hav to use some courser grit to finish some of the hull seams. Use some red filler that uses the hardner to fill any gaps you may find.

[nichismo]

Me and speed have been discussing how I'll seal off the engine well, and Phil thoughtfully provided some helpful insight with the included instructions. I'm going to install a couple bulkheads in the tub, and then a lip along the top of the walls With some 3/16" square birch. I'll then run 1/16" ply on top of the birch with a little overhang, then attach more ply underneath so that I can make a flat cover sit flush on top of that to be easily taped up Before hittin the water.

I'm going to buy some heavy fiberglass or cf cloth to reinforce the bulkheads and engine mount. Im still having a little bit of trouble deciding where I'll place the lipos. Also that reminds me, how do you guys suggest I mount my steering servo? Should I purchase a water proof one and mount it closer to the transom underneath the turbine tray? Or inside the engine well? Sideways or flat?

And thanks phil, I just picked up some wet dry sandpaper last night, I still need some more though. I couldn't get any of the high grit I needed for polishing my hardware.

Do you think I could just use some glazing putty? Like bondo?

[Agitator]

Lipos should go as far forward as possible, mount the servo in the compartment, use one of the mounts carried by OSE, I mount mine upright.

Resampled952012-12-239516-53-0795843.jpg

servo-mount-3_medium.JPG

[nichismo]

okay. I was considering putting a lipo pack inside the actual hull through the tub wall holes, and theyd probably be parallel with the motor or just a tad farther up, but im just going to place them inside the engine well to be sure they will be in the safest, driest position. What is the perspective on mounting a servo straight up vs sideways? if any

Is it worth laying carbon fiber fabric or kevlar throughout the tub in a fiberglass hull like how the wooden builds are? or am I better off only adding what I need essentially and nothing else?