Syncron build-newbie

[BHChieftain]

Here are the pics of the floatation.

-Chief

[BHChieftain]

Day 6

Read a few posts about coupler problems and losing drive shafts, so I decided to take a closer look at the drive hardware shipped with the syncron. Looks like a pretty good design-- the coupler has a sleeve inside that grabs the flex shaft, and has flat spots cut to accept 2 set screws to clamp it down. Seems pretty bullet proof.

But I still needed to grind a flat spot on the motor shaft. Marked the set screw location with a sharpie, and cut it freehand with a dremel tool using a grind wheel attachment--it was a lot easier than I thought it would be, only took a minute with a light touch. Thanks all for the tips on sealing the motor in a plastic bag to protect it from metal shavings! Used loctite on the set screws and motor mount screws when I put it back in the boat.

-Chief

[BHChieftain]

Day 7-

Installed cooling system. That hydra 240 is a pain in the &*#, between the double 10g wires and double cooling lines. The ESC is basically two 120 hydras clamped together...

Anyway, cut a hole in the hull to accept the water outlet (gasp!), and then spent about a 1/2 hour getting the cooling lines on the ESC... the cooling line is thick, and there is very little space between the dual sets of water intake ports on the ESC, so you have to work both lines on at the same time.

I was inspired by Steven's syncron layout which had the ESC velcro'd on top of the motor-- decided to give it a try.

Discovered that the ESC's on-board BEC can't handle more than 3S, so now I need to install a UBEC... back to the soldering iron!!!

-Chief

[Unkle Chopper]

Just seen your build and have a few tips...

you can see my synchron here

I would reccomend getting the ESC over to the right hand side of the boat and as far aft as possible i actually mounted mine on balsa blocks that are expoxied to the floor allowing a strap to pass through and keeping water away should the boat get wet on the inside

the balance of the boat when running 4 cells in my opinion is pretty good however the motor mount on these sits slightly too far forward which means the COG is slightly restricted making the boat run a little to wet in flat conditions however when it is rough they absolutly scream

see some high speed video here (boat 7) is my synchron in action

I have tested various motor an prop combinations and now have a boat that is very fast and winning regulary on the water, to say i am pleased with the hull is an understatement they really are fantastic boats

I am following your build now and look forward to seeing a completed boat on the water

[BHChieftain]

Just seen your build and have a few tips...

you can see my synchron here

I would reccomend getting the ESC over to the right hand side of the boat and as far aft as possible i actually mounted mine on balsa blocks that are expoxied to the floor allowing a strap to pass through and keeping water away should the boat get wet on the inside

the balance of the boat when running 4 cells in my opinion is pretty good however the motor mount on these sits slightly too far forward which means the COG is slightly restricted making the boat run a little to wet in flat conditions however when it is rough they absolutly scream

see some high speed video here (boat 7) is my synchron in action

I have tested various motor an prop combinations and now have a boat that is very fast and winning regulary on the water, to say i am pleased with the hull is an understatement they really are fantastic boats

I am following your build now and look forward to seeing a completed boat on the water

Perfect timing on your post!

Today I put the boat in the bathtub with the batteries on both sides of the motor, and tested the flood chamber... would not flip over. My new config looks pretty much like yours... I moved the ESC to the right side, and put the right side battery up front in the nose, just left of center. With that weight distribution, she'll turn upright when capsized. I'll post a few more pictures later.

-Chief

[Unkle Chopper]

Perfect timing on your post!

I moved the ESC to the right side, and put the right side battery up front in the nose, just left of center.

-Chief

Hi,

I thought i would help you with battery palcement so have taken a couple of extra shots of my boat.

Here you can see exactly where i place a 4s1p pack if the weight is any further forward the boat will run too wet, this may not be a problem if you are not racing although it may dive a little in rough conditions.

I have a couple of other things, if i use a naviga legal pack (<560g) to race in mono 2 I add 25g of weight when I strap the battery in just to help the boat roll, if i use the pack shown (584g) it is not needed. however if it is really windy when racing add a furter 30g of lead and this helps roll that little bit quicker.

do you plan on adding vent holes to the flood chambe? if you do the boat will roll better. albeit it feels bad cutting holes in a new boat. if you dont at least consider a single hole at the front of the chamber to let the air out as it floods, you can see here i have them top and bottom and i fill the bit at the front with expoxy to make sure it is strong incase i get hit in a race.

[BHChieftain]

Hi Unkle Chopper,
I really appreciate the shots on your layout, thanks.

I'm running two 2S1P packs in serial, so I have a few more options on battery placement-- the first battery is up vertically against the flood chamber, the second is now up towards the nose cone on the left side floor. If I put them both vertically along the flood chamber, she lists a lot to the port side.

At this point I'm more interested in sport running, although I do plan to enter into some races, so I'd rather delay drilling more holes in the flood chamber-- right now there is one hole up towards the nose break the vacuum. She'll turn over, albiet fairly slowly. Would adding more holes increase the turning force to a point where I could put the battery that's currently in the nose back to the starboard side next to the motor (I woudn't think so, but it would balance the boat better).

-Chief

[BHChieftain]

I have a castle creations 10A UBEC coming in next week which I'll install to override the internal BEC since I'm running 4S. What voltage output should I be using on the UBEC? Servo is a Traxxas 2056 and the receiver is a Spektrum MR3000.

Thanks,
-Chief

[BHChieftain]

Chief,
We have the same CC UBEC we are not using if you want to borrow it to test on Saturday...
Bigwaveohs

USPS says it should show up today, so I plan to solder it up tonight. All systems go for the first test run on Saturday!

-Chief

[BHChieftain]

Yesterday I did some leak testing on the boat in the bathtub. It is watertight except for the hatch-- no matter how well I tape it I get some leaking. I tested this by building a temporary "gasket" using narrow strips of double sided tape, then taped the hatch on top of that. This stopped the leaking.

Anybody have tips on building a hatch gasket? I was thinking about a bead of silicon sealant, but not sure if that would work well.

-Chief

[BakedMopar]

This is a very nice build. Good luck with it

[BHChieftain]

Day 8- Waterproofing

-For the water outlet, I found a rubber washer from a faucet repair kit. Used a rattail rasp to widen it and screwed it in place, then put the metal nut back on.

-Water leaked up the flexshaft until I greased it. That fixed it.

-As mentioned in an earlier post, everything else was watertight except where I taped down the hatch. I made a makeshift gasket from doublesided tape, and that worked well. Still thinking about a more permanent solution.

-Chief

[BHChieftain]

Day 9- Installing UBEC, Batteries, and Receiver

-Luckily, last week I stumbled across a post that flagged the internal ESC BECs usually can't handle 4S... so, with much sorrow, I had to resolder the ESC battery-side wires with the UBEC wires. Sure enough, the bullets came off so I basically had to redo the whole thing (those blasted double 10g wires...).

-Put the boat in the tub with the planned battery config which was lipo1 mounted along the flood chamber wall, and lipo2 on the right side of the motor. Boat would not turn over when capsized, so I needed to reposition the batteries. Moved lipo2 up towards the nose, just left of center. I moved the ESC from the top of the motor to the right side of the motor, and just as well as I needed a place to secure the UBEC. Both the ESC and UBEC are secured with velcro on the floor-- Later I might add a mount to get them off the floor in case of a leak (advice from Unkle Chopper).

-Since I moved the battery into the nose, I needed to split the nose floatation into two pieces. The upper piece is secured by velcro. The battery install procedure is battery first, then loose floatation piece no. 1 to the right of the battery, then secured by flotation piece no. 2 which sits above the battery (with velcro) and locks the first piece in.

-Ran the Spektrum MR3000 receiver wires up under the lip of the hull. Had a hard time finding tape that would secure it-- settled on servo tape which worked nicely

-Held my breath and powered everything up--- life! I also remembered to enter calibration mode to set the right lipo cutoff for 4S (12v). As a bonus, the prop turns in the correct direction...

All ready for a test run tomorrow!

-Chief

[Unkle Chopper]

The build is looking good chief !, I will post some pics of my little mounts after race day tomorrow they are really simple made from balsa and laminated in epoxy

having seen the pics of you cells in place if you can get the cell that sits up front as far back and as close to the flood chamber as possible you might get close to her rolling pretty well with not too much adjustment, a good tip is to just try sticking some lead balance weights on the boat for temporary tests. most hobby stores have them with a adhesive backing available as they are used in touring car racing regularly to meet weight requirements, i play around sticking them inside and out to see how much encouragement the boat actually needs before permanently fixing in place with epoxy.

[j.m.]

Those wires could use a little shortening to tidy things up, but your build is perfect otherwise. That's a very clean hull with nice lines and 'American' style with 'Euro' design. Lovely!

Jon