today's work

[SteveNeill]

I have to give credit where credit is due: It was Brian Starkes who, nearly 20 years ago, clued me in on to the use of magnets to achieve quick-connect, zero back-lash linkage unions as well as deck and panel closures. Brian is one of the many unsung heroes in this game who have contributed their experience and inventions that have grown the hobby.



The small magnetic couplers are of my design. The bigger, more robust ones were created by Bob Martin himself.

And Tom Chalfant has come up with a very innovative use of magnetic unions: he's worked out a method of making up hydraulic and pneumatic lines using magnets to make the union fast.




David

So David is either you or Tom(who I also know ans sail with) offer these?

[He Who Shall Not Be Named]

The larger volume ballast tanks of the Modular SubDriver (MSD) require a higher rate of air flow during the 'blow' cycle. My Boss sent me two large air-pumps to play with, the goal to optimize them to fit and mount within the tight confines of a 3" Lexan cylinder.



I had to hack and slash at the pump-motor housing to get it to fit within the cylinder. I found the best means of mounting the pump-motor unit to the cast resin ballast tank after union was with two lengths of K&S L-beam, everything secured with 2-56 machine screws.







Here I present the modified pump-motor and one stock, yet to be molested by the shop machine tools.







I have yet to affirm that this single-stage diaphragm pump will move water as well as air without leaking into the cylinder. That investigation to happen tomorrow -- but I'm confident, after examination of the seals (both diaphragm and check-valves) that no modifications will be necessary … we'll see.

The big issue is the need to come up with a snorkel valve and safety float-valve that can deal with the high flow rate and higher differential pressure -- that's gonna take some work!

David

[trout]

Those look powerful! Look like they could suck the chrome off a trailer hitch! Serious movement.
I think you might find the air can be replaced through the existing sizes just fine.

[bwi 971]

I really enjoying this David......quietly following at the sideline......until I saw this.....you never stop amazing me.......this is so brilliant.......can't get over it......I hate you!
Grtz,
Bart

[He Who Shall Not Be Named]

I really enjoying this David......quietly following at the sideline......until I saw this.....you never stop amazing me.......this is so brilliant.......can't get over it......I hate you!
Grtz,
Bart

Hey, Bart!

Good to hear from you. And thanks. I have my moments.

I hope you are fairing well through all this Chinese-Flu nonsense. Been a rough year for the world in general, me thinks. We'll get through it, though. Stay tough.

I hate you too, pal.

David

[bwi 971]

Yeah, I’m ok.......I’m used to this quarantine stuff.......earlier my longest sea voyage was 47 days.......this beats it though, 49 days and counting.......my playground normally stops at the garden anyway.....but I think I'm not the average guy....I see a lot of people struggling with this ****.......the elderly homes are having a nightmare.....2/3 of our daily deaths due to C19 are registered in the elderly homes......nothing can be done, so sad to be powerless against this beast......Vicky does the shopping for my and her parents.......everything is disinfected before drop-off and pickup.....crazy times indeed. Stay safe sir!

Grtz,
Bart

[He Who Shall Not Be Named]

Yeah, I’m ok.......I’m used to this quarantine stuff.......earlier my longest sea voyage was 47 days.......this beats it though, 49 days and counting.......my playground normally stops at the garden anyway.....but I think I'm not the average guy....I see a lot of people struggling with this ****.......the elderly homes are having a nightmare.....2/3 of our daily deaths due to C19 are registered in the elderly homes......nothing can be done, so sad to be powerless against this beast......Vicky does the shopping for my and her parents.......everything is disinfected before drop-off and pickup.....crazy times indeed. Stay safe sir!

Grtz,
Bart

You make an interesting observation about those of us used to long underway times aboard ship/boat, Bart. Nine patrols on the WEBSTER accustomed me to living and working in a confined space for months at a time. And, yes, there are those -- most people -- who have not been so tested. With this Chinese-Flu most good people are dealing with it like adults, but for some it's hell not being able to run around freely.

Thank you, Chinese Communist Party! Well played, you SOB's!

Our best to you and Vicky, Bart. Keep your heads above water for the duration -- this too shall pass.

David & Ellie

[He Who Shall Not Be Named]

[rwtdiver]

It's such a joy to see a "TRUE MASTER" at work! Really nice work David!

Rob

"Firemen can stand the heat"

[He Who Shall Not Be Named]

I'm brokering a ready-to-run r/c submarine for a friend. He's a bit disabled, but a good guy and a very competent model-builder, but is down to one hand now. So, another friend, Tom Chalfant, has provided this guy with a 1/72 SKIPJACK r/c submarine; I'm in the middle integrating a new r/c unit with the existing SubDriver system, checking out, and getting the boat operational before sending it to its new owner. This is some of that work:







And I continue to produce new masters to support our new Modular SubDriver (MSD) product. We're adding 3" unions and bulkheads that will increase the adaptability of the product:

















From these completed masters I'll make RTV silicon rubber tools from which I will produce cast resin production parts.

[rwtdiver]

And as the kind and generous man that you truly are! David, you are again helping a friend or someone else in need!

Am I correct, that the masters in the above photos are but one process required for a three process part? What material do you use to make the master? Then you mix up a silicon rubber that you pour over the masters, and the silicon rubber mold is actually the final mold that you poor the resin mixture into to form the final product? What a time laden and exacting process this is.

Anyone that complains about the price on one of your SD or MSD should really look at and "appreciate" the real process required to fabricate your products!

Rob

"Firemen can stand the heat"

[He Who Shall Not Be Named]

And as the kind and generous man that you truly are! David, you are again helping a friend or someone else in need!

Am I correct, that the masters in the above photos are but one process required for a three process part? What material do you use to make the master? Then you mix up a silicon rubber that you pour over the masters, and the silicon rubber mold is actually the final mold that you poor the resin mixture into to form the final product? What a time laden and exacting process this is.

Anyone that complains about the price on one of your SD or MSD should really look at and "appreciate" the real process required to fabricate your products!

Rob

"Firemen can stand the heat"

My 'kindness' is nothing more than fulfilment of a moral obligation to 'pay back' those who have helped me in the past by assisting those I see as worthy today; those interested in continuing the Craft.

We individuals are but little elements in the maintenance of the Craft. If it is not passed down from individual to individual the Craft will be lost.

Yes, kit production is typically a three-step process: Master. Tool. Production part.

As a budding Pattern-maker, many moons ago, I used seasoned, kiln dried, Pine as the medium from which I formed patterns.


Later, I embraced the synthetic high-density foam pattern making medium, RenShape. Available in various densities.



The pattern is then employed to give form, as a negative cavity, to the mold, or tool. For resin and metal casting I employ Tin cured silicon rubber. The BJB, TC-5050 is the go-to rubber of choice in my shop.



And, finally, the production casting is made by pouring catalyzed resin into the tool, waiting for it to change state, and then extracting the finished part from the tool. I prefer the Alumilite polyurethan casting resin.

[He Who Shall Not Be Named]

Tool making took up most of today's shop time, but I did get in an hour to identify and correct one leaking pushrod seal in the SubDriver that goes with that RTR 1/72 SKIPJACK model I'm readying for a friend.

The leak identified after submerging the SD in the test tank and applying a little pressure -- if there are any leaks in the system they evidence as a stream of bubbles emanating from the problem area. Sure as ****, one of the seals was leaking. It was identified, the SD pulled out of the water, dried, and the bad tooth pulled and replaced!



As the pushrod seals are secured with RTV silicon gasket adhesive, it was an easy matter to push the bad pushrod seal out of the motor bulkhead and replace it with a new pushrod seal.



After the RTV had cured hard enough to reinstall the pushrod, I did so and made up the servo bell-crank to the pushrod and did the leak-test again to insure everything was water tight.



Time had come to mount all the MSD bulkheads, unions, and servo foundation masters on their respective mold-boards and prepare things for the first half of the RTV silicon rubber tools.

[He Who Shall Not Be Named]

[He Who Shall Not Be Named]

I receltly got an order for fittings to complement the GRP hulls of 1/96 KILO and BLUEBACK r/c submarine kits needed by my boss at Nautilus Drydocks. Typical resin casting job, but a nice departure from the boring MSD work I've been doing for so many weeks now.

These three beauty shots are of my personal KILO and BLUEBACK boats that I run for fun. Both are sterling performers on and under the water. And their relatively small size permits me to operate them in almost any body of fresh water. my go-to play toys!

https://youtu.be/W9Pg0zGb5Wo

And here are the gory pictures of the fittings being cast up and prepared for shipment.