Progress on The Sir Frankie Crisp.....in LOCKDOWN!!! (cont'd)

[Ben Brigham]

Hi all,

Here's a radiowave-antenna-interference-related question. Hopefully someone in the organization has some experience with this & can steer me to a solution.
My receiver antenna will be running through a "dry" plastic tube as part of the radio systems' dry space. I'd like to be able to pull it through this tube by latching it to the 1/16" diam bungee cord. The tube is pretty narrow in diameter.
I've been seeking the perfect "lobster claw" jewelry clasp to connect the antenna to the bungee. But they all seem to be some type of metal and I don't want the proximity of any kind of metal at the end of the antenna for fear of adversely reducing the antenna's signal receptivity and hence radio range. So I've been seeking cf/epoxy or plastic clasps but am unable to find the ideal candidate. I may have to fabricate one but am hoping to avoid that headache.
Has anyone else found any source for miniature non-metal clasps that could fit in a ~3mm space? Thanks! BB

[Ralph --- SSBN 598]

If I understand, you want to get your antenna through the small plastic tube.

I do this by using a needle and thread.
I put the thread through the needle eye and doublwe the length plus a little more than the length of the tube.
Drop the needle in the tube and move the model around keeping the tube point down.
Feed the thread in to the tube as the needle progressess until it cones out the other end.
Let one end of the thread go and pull it through the tube.
Take the thread end and make a couple of half hitches arounf the antenna end.
A touch of CA on the thread and tube end. (just enough to attach the thread to the antenna)

Pull the thread back through the tube bring the antenna with it.
Then I bend the thread over the end of the tube and CA the thread to the side of the tube.
When cured, I put silicone over the end of the tube and push it down over the end of the antenna.
This is in case I need to remove it later.
I make a small loop out of the thread and tape it to the tube. (1/4" length of heat shrink works well too)
Then I have the thread already attached to the antenna end if needed again.

[coryhenry]

Maybe something like these plastic hose clamps?

https://www.amazon.com/60-Pcs-Speedy-Double-Plastic-Assortment/dp/B07VSNPG3V/ref=sr_1_1_sspa?dchild=1&keywords=small+plastic+clamps&qid=1597042934&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyOTFWTzVVQU0xOVoxJmVuY3J5cHRlZElkPUEwNDI0MzAxMkJKQzVLMUIzOUFaWCZlbmNyeXB0ZWRBZElkPUEwNjIyNjM0M1FEM0gxNUJJNE41WSZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

[Ben Brigham]

Thanks Ralph, thanks Cory,

I should probably just shut up & draw, huh?


This picture shows the design that I've committed to, with the little enclosed return-wheels at the end. Ralph: your alternate idea would work if the end were openable, but unfortunately it isn't.
I found little tiny clips for lanyards. (Apparently mice attend ComicCon) They're 3mm across which I think will work. BUT the concern is that since they're metal, would their presence at the end of the antenna adversely affect range?
Anyone? Bueller?

Thanks!
BB

[Ben Brigham]

(and yes: I pull the orange bungee to draw the antenna up into the tube, then tie off the excess bungee.)
(when I want to remove the receiver from the box, (rare situation but it happens) I pull the antenna back, then disconnect the clip. That's the logic of this design.)

[coryhenry]

I don't think you would have an issue using a stainless clip and radio interference.

[Ben Brigham]

Okay, thanks coryhenry, I'll risk it & see what happens.

[Ben Brigham]

First light!
It went kind of well I guess.



There was no bluish smoke belching out from anywhere when I powered it up, so yay me. Most of the servo controls were responsive, except for the starboard ESC and the ballast servo which is odd.
So there are a few things to troubleshoot but this is a HUGE step forward. The ballast tank feed/drain assembly is in the works and I seem to have the space needed to get it done.
(crossing webbed fingers)

[salmon]

Ben,
How many ESC you got in there? Just to check this off the list, how many have the red wire going to the RX? (Should only be one - or there can only be one, if you want to think of a movie)
Definitely Yah you! I chuckled at that one.
Peace,
Tom

[Ben Brigham]

Brilliant!! Great idea, Tom! That's a very real possibility.
Technically there ought to be none, since the entire system is now being powered via a Nautilus Drydocks BLM. So both red wires ought to get yoinked.

Initially I had only the one ESC, then evolved the design to have two. But it's certainly possible that in all the hubbub I neglected to pull the red wire from the second ESC.
I'm going to open up the Brain Box tomorrow when I have time, & that'll be my first spot to check.
Thank you! (will apprise)

[Ben Brigham]

Hey Tom, Ralph, Will, anyone with knowledge of RC electronics history,

The BLM module instructions describe different setup procedures depending on whether the receiver (in my case, Ralph's old Futaba R168DF 75mHz) has a built-in failsafe or not.
I'm assuming a receiver that, er, "classic" does not, but can anyone confirm/refute?

thanksthanks!
BB

[thor]

Only the R148DP has the failsafe(PCM). The R148DF does not have a built in failsafe.

[Ben Brigham]

Thanks Matt! (I believe I understood you there )

[Ben Brigham]

Hi all,



Okay, we’ve got our eyes on the future here. So we’re not going to mention the non-explosion that didn’t happen and in no way shorted out both speed controllers at the same time, making me extremely un-humiliated & nothing even close to despondent. The non-tragic irony of my having joked about blue smoke bursting out of the hull, only hours before on the Subcommittee’s Builder Thread, made it even less cringe-worthy.



Touching my face in reckless abandon

The replacement ESC’s had no need to arrive in the mail a few days ago, so there would be no reason whatsoever to completely rewire the power system to prevent something that did’nt at all happen to never, ever happen again. The whole experience has left me not-nonplussed. In other words my chosen hobby has left me plussed, very plussed. It really plussed me off.



Fortunately in the intervening time (that wasn’t available), I was (really, seriously now) able to wrap up a crap-ton of little tasks, correcting alignments, completing the leak detector’s warning light & siren, adding in magnetic latches here & there, and just dabbling in some light airbrushing.


I am now finishing up assembling the jewel of the ballast system; the steampunky brass bellcrank and propel triple-valve assembly. It came together very quickly and seems to work great.



Next task is crafting an acrylic ‘roof’ for the ballast tank. This is expected to be a fairly miserable slog with thermoforming, similar to making the roof for the battery tray only quite a bit more demanding in terms of steps. The roof will need two sealable hatches integrated into the design. The amorphous hull, and getting the acrylic piece (or pieces) through the access area will be tricky. Will keep everyone updated.

[Ben Brigham]

Hi all,



Some good news to share! I installed & rewired in a new BEC and BLM, and am now 100% done on the electronics. The BLM now shows all four LEDs signifying full charge, and has been configured for my system. This is sort of a champagne moment for me.



In a sort of morbid way, the 'big short' event was a blessing in disguise in that it forced me to improve basically everything about the wiring system, even little stuff.

Also, to my enormous relief, the connector that I use along the top of the Brain Box was tested for water integrity and passed with flying colors. Whether the gasket was dry or lubed with synthetic camera oil, not a single weep came through on the test subject.



I had been really nervous, after having committed to this design, ostensibly "waterproof" according to the promotional, out of necessity/convenience. Spidey-sense was really tingling, especially after Kevin MacLeod mentioned in an email that he's always been leery about them too. And a formal test in my apartment's pool was always planned but pushed off to the future due to other hair-on-fire emergencies. But the connector design works great, sent down four times, held at 7 feet deep which is basically the Marianas Trench as far as I'm concerned.

Next up: the ballast tank roof!