Tom Chalfant - Bronco Type XXIII

[trout]

Got the right temperament to tackle tightening the rudder's grub screw.
I needed to make a tool to reach. I took a length of brass rod and drilled a hole at the end slightly larger than the hex wrench (.050). Soldered a small cut off of the wrench into the end.

Took the hull outside and was able to finally get the rudder tight.
There are numerous ways to put your WTC together. So, here is mine. I placed the Mtroniks under the motor.

Placed some velcro on the tray and some under the RX.

Placing the RX sideways will not work. It is too wide especially when the servos get plugged in. I could mount it under the shelf where it is a wider part of the tube, but still too tight. Could not mount it vertically, the RX was too tall. I could cut a slot out of the tray, but it would interfere with the vent servo.

Fortunately, it looks like placing it this way it will just go over the servo.

The downside is my speed controller's connector is short going forward.

[He Who Shall Not Be Named]

Take the receiver board(s) out of the plastic case, wrap them in heat-shrink and it will fit between the servos, Tom.



M

[trout]

I opened the case on the wFly receiver, but it did not look like I would save much. Will try again. Thank you.

[trout]

Needed to prepare a mold for the weights. Using potters clay plastic wrap, pushed three separate locations. Now I will let it dry.

cut out a rectangle to hold one end of the Deans plug like David shown in his builds.

connected to this plug will be the ESC, Voltage Regulator, pump power.

Pushing it all in almost fit. I still did not see that much savings removing the case, yet I see David's photos showing it out. My servos are larger, that may be a difference and I need the arm on one to go inwards. So, I will play with what I got.

I opened the gap by cutting out a portion on each side. This allowed me to place the receiver further aft. (side note the servo plugs were just put in, not oriented correctly, I believe signal is top)

[trout]

Yesterday and today I was able to get more work done.
Working further on wiring, the battery end cap needed to have the opening for the switch made larger for the one I had. I traced the outline of the switch and ground out the rough shape to begin with. Then drilled the opening for the thread to go through. With that I was able to refine the areas needing to be removed. Once it fit in well i used RTV silicon to seal it in.

Then put on the boot and also sealed that on with RTV silicon.

The wiring on the end cap needs several things, the cable strain-relief block (provided which I already drilled out), pair of connectors (here is a Deans connector), and a fuse holder (some do not use them, but it is what I was taught and so I do it).

Here it is completed.

Going back to the engine room, since I am using a BEC, I need to prevent the Mtronik's ESC from providing power with its built in BEC.
The process is easy, the red or positive line going to the receiver from the Mtronik's ESC needs to be cut or as I have chosen to do, remove the pin (just in case I want to reuse the ESC and it's BEC). You will need a pointed object such as straight pin, tweezers, or x-acto blade.

Lift the tiny tab with the point.

While the tip of the blade is holding the tab up, pull the center or red wire out. I folded it back and shrink taped it.

Put it all together and flipped the power switch, and nothing happened. There is that brief moment you wonder what is going on and then logic steps in. Did I solder all connectors? did any break? is the power connected to the receiver? All were good and then it hit me, I forgot to put a fuse in, dummy. Once in, it worked!

I have a 5000mAh battery, but it is 7.4v The pump definitely runs slower using this battery, but what a nice long runtime. That being typed, not much room for shifting the weight like I had hoped to use.

Then there are these I can use. I like the elite pack, and could double them up (parallel wiring). For the moment, I will use the 7.4v and trim with it.

[trout]

Unfortunately, I did not photograph the steps I did, but maybe I can describe what I did sufficiently. The potter's clay I let dry in the bottom of the hull, came out easily because of the plastic wrap. I took the clay pieces and flipped them upside down on a bed of modeling clay. Tried to level them and trimmed the modeling clay close to the potter's clay pieces. I built Lego walls around the molded pieces. I am going to use plaster of paris, mainly because that is what I have, but it is also a test to see if it will be adequate for a simple medium to cast lead ballast.

Let that set up and update later.

[redboat219]

How about using resin encapsulated birdshot?

[trout]

Absolutely, that would work Romel. I went looking for shot, but the quantity was in the 25 pound or more range with a cost more than I wanted to spend. Most of the lead I have used came from a tire repair place. When I bought tires last, I ask as part of the "deal" that they throw in several pounds of lead. On this build being so close to Christmas, I needed to be conservative in spending and bought 32oz of weights for $11. Since I do not know where my weight will be exactly, or the amount I need, my thinking is to make these three different sized weight molds will give me the right combination for this sub. Hopefully (slight chance I know), I might be able to get two pulls from the mold. If I knew exact placement or even approximately where I needed it, I could make dams and pour a shot and resin mixture directly into the hull (I think there would be no reaction with the styrene). Also, on this build I may need to play with the location of the ballast tank and might need to rip it all out to start trimming all over again. Making lead pieces allows me to move them around. I could also put a mixture of shot and resin into my molds. The density would obviously not be the same as solid lead.
Romel thinking it out, it would be nice to have several master sets of weights made for different diameters that could be reused for testing weight placement.....will have to ponder that. Thank you for the suggestion.

[crazygary]

Tom-
Would bb's work for your needs?
Unfortunately, they're mostly made from copper nowadays, but are cheap and available pretty much anywhere!
Have used them with success in a couple of my "targets".
Just a thought!
Hope you had a nice Christmas!

[trout]

Sure Gary, they would work, but all the above still applies. BBs are not as dense as lead so more space would be taken up for the same weight.

[Kazzer]

How about using resin encapsulated birdshot?

This is what I use to make our boat weights. I am waiting on a master mold from Mr. M for this boat

[He Who Shall Not Be Named]

This is what I use to make our boat weights. I am waiting on a master mold from Mr. M for this boat

Once I get my pitch-down-from-hell problem worked out with my Type-23 (am awaiting to see how Tom's model behaves before trying again), I'll fix the location and amounts of fixed ballast and foam, work up masters representing those items and get them off to you, Mike.

How's the vacuum-bagging going?

M

[trout]

The Plaster of Paris set up. Flipped over the mold and removed the clay.

Legos designed this great tool for taking apart the blocks.

A surprise happened once the modeling clay was removed. The moisture from the plaster re-hydrated the potter's clay and it came out easily.

I put the molds into the oven and baked at 130 degrees for 6 hours. Then let set overnight. In the meantime, I got a Hot Pot 2 (a lead melting ladle). Researching I saw a post about graphite used as a lube to remove your casting. It just so happens that we are building another pinewood derby car and have some graphite for the wheels. The question is would it work with a plaster mold? Sprinkled some in each mold and rubbed it in good.

The first pull went great. The lead fell out of two of the three molds. Two molds broke. Since it is a time to experiment, a little CA to put the molds together and give it a try.

I was able to get a second pull and all my lead is poured.

The best part is it fits!

[greenman407]

Nice work there! Do your kids get involved? Mine couldnt have cared less.

[trout]

I opened the case on the wFly receiver, but it did not look like I would save much. Will try again. Thank you.

Sam bounces in and out of liking it. He likes commanding a sub at the pool. He says he wants to build one. He really likes the big Skipjack, so maybe we will build the smaller Skipjack together. The larger sub seems to be easier to put together to me, but to Sam the size is equal to the hardness and puts him off.