today's work

[redboat219]

So that's what happened to mine.

Drilled a small hole at the end of the crack to prevent it progressing further then used UV cured glue to seal the crack. Still haven't tested it though.

[He Who Shall Not Be Named]

In the late 80's Ellie and I introduced to the American continent the concept of the cylindrical, removable water tight cylinder (WTC). We were not the first -- just the ones who popularized the system on this side of the world.



The WTC is a complete system that features a watertight cylinder that contains three major subsystems needed to operate an r/c submarine model: Control, propulsion, and variable ballast. This basic layout applied to cylinders of varying diameter, wall thickness, and length -- each type suited for a specific application.



We quickly settled on polycarbonate clear plastic tube as the material of choice for the cylinder because of its useful physical properties. Lexan is easy to machine, and is much less susceptible to damage than the cheaper (and easier to source) acrylic plastic most people are familiar with.



For twenty years we produced hundreds of systems with no reports of failure of the plastic cylinder. However, about ten years ago, we started to get reports from the field that some WTC's were evidencing cracks -- these usually emanating from a drilled hole adjacent to an internal bulkhead. Should one or more of these cracks in the cylinder run through an internal bulkhead o-ring then flooding of the space within was inevitable.





The rate of these failure reports escalated through the years to the point where, today, I'm seeing a failure rate of nearly ten-percent of the units I produce for myself and friends (I retired from the business about a year ago). The situation was most unacceptable!

A situation that was only resolved recently as Bob Martin, of the Nautilus Drydocks, developed a new line of SubDrivers; a product that cleverly employs a modular scheme of Lexan cylinder segments which do not require drilled holes in the Lexan plastic cylinder.

I just could not let this cracking problem go. So, I did some reading and found that I could easily anneal my Lexan cylinders in the kitchen oven, thus stress relieving the materials crystalline structure, likely caused by some bean-counters implementation of frugal production practices -- I suspect, as a coast saving measure, that either the chemistry of the plastic and/or the post extrusion temperature control protocol had either been eliminated or curtailed.

Bottom line is this: today's Lexan plastic cylinder (and this varies from manufacturer to manufacturer) is much more brittle and prone to cracking than the Lexan products of old.

The solution was to anneal the Lexan cylinders here, in the kitchen.





I found that preheating the oven to 240-degree F, then loading it with cut-to-length cylinders, then waiting twenty-hours for the oven temperature to creep back down to room-temperature did the job of re-organizing the crystalline structure of the plastic to the point where stress forces imparted during manufacture were relieved. I no longer observed significant cracking of the Lexan cylinder, no matter how tight I made a fastener running through a drilled hole.



A few months ago I cut two lengths of 2" diameter Lexan cylinder. One I annealed, the other was not. I then mounted an internal bulkhead and emergency ballast blow cylinder within each, tightening the screws and retaining collar with unreasonable force. Show time!



Recently I examined the test articles: Sure enough, the annealed one evidenced no cracking; the one that was not annealed had cracking.



So. Problem solved. Henceforth all WTC Lexan cylinders will be annealed!

[He Who Shall Not Be Named]

[He Who Shall Not Be Named]

[He Who Shall Not Be Named]

[He Who Shall Not Be Named]

USS Scorpion had the upper deadlights covered before she sank.

Mike's Dad was on the boat during work-up before first patrol. That's how I'm representing the model.

David

[Das Boot]

USS Scorpion had the upper deadlights covered before she sank.

[Ken_NJ]

Perfect timing. Just so happens I glued those deadlights onto the sail today. What is the purpose of these in a submarine? On your weathering thread I believe you misted either the inside or outside of the deadlight black? Which was it, inside or outside?

I'm guessing this is not one of your many to do boats in retirement as you already have a Skipjack you brings to events.

[He Who Shall Not Be Named]

[He Who Shall Not Be Named]

Wow... it looks a lot larger than 1/72nd! Great looking model, and a nice size. No wonder so many of them end up being R/C.

Rumor has it the lead-man on that kit had that very application in mind from the start.

David

[goshawk823]

It's the Mobius 1/72 SKIPJACK kit.

Wow... it looks a lot larger than 1/72nd! Great looking model, and a nice size. No wonder so many of them end up being R/C.

[He Who Shall Not Be Named]

It's the Mobius 1/72 SKIPJACK kit.

[goshawk823]

So. James. we gonna start picking out furniture together now?

On a more serious note...

It pleases me no end to know that some of the work Ellie and I did over the years is appreciated. We learned our craft from others, and my 'Today's Work' postings (magazine articles, a few books, and countless lecture and Q&A panels) is an attempt to keep this Craft alive.

But, do more than study the Craft, James. Practice it! Use your hands and brain. Most rewarding.

David
D&E Miniatures

hell, David... it's one of my favorite daily checks on this site too. You and Ellie documented so much stuff over the years that learning stuff from the all still photos is even possible.

That last one looks like a DeBoer's Skipjack, if I'm not mistaken. Seems to be about the correct scale?

[He Who Shall Not Be Named]

For me, the greatest joy is to log on to the forum at the end of the day and go to David's "Today's Work" section and see what David has posted about his magic, which is what gives me the most pleasure to enjoy these masterpieces...

So. James. we gonna start picking out furniture together now?

On a more serious note...

It pleases me no end to know that some of the work Ellie and I did over the years is appreciated. We learned our craft from others, and my 'Today's Work' postings (magazine articles, a few books, and countless lecture and Q&A panels) is an attempt to keep this Craft alive.

But, do more than study the Craft, James. Practice it! Use your hands and brain. Most rewarding.

David
D&E Miniatures

[James Wittaker]

For me, the greatest joy is to log on to the forum at the end of the day and go to David's "Today's Work" section and see what David has posted about his magic, which is what gives me the most pleasure to enjoy these masterpieces...