Report To The Cabal: A 1/48 SEAWOLF Pump-Jet, Part-7

I've done a bit more work on the SEAWOLF PJ than this photo essay indicates, but I'm sending this along as I've collected just about the limit of stills I can send in one e-mail Report.

The last item, the rotor ring, has been fabricated and attached. Now it's left to the rest of this evening to built up fillets between the rotor tips and inside face of the rotor ring. It's almost time to do the final spot fill and sand and the masters will be ready for tool making.

But, I'm backordered on WTC's and some other work that simply has to be done before the first-of-the-year, so there will not be another report here for about a week. Tool making for the first of the year!

The two pump-jet halves were given a heavy shot of primer-gray, making the surface a constant gray makes it easier for me to see the work as I make the final cuts needed to fit the ringed rotor. Not only does the thick DuPont 131S gray, acrylic lacquer automative primer afford a better surface to see as I work, but the primer does a great job of filling file and sanding marks -- typically only three heavy applications of the primer, sanding with #240 between each, is enough to fill all dings and scratches.

The long dreaded operation of cutting out the rotor ring, and corresponding groove into the inside face of the after shroud half, had come upon me ... and was over ... before I knew it. Don't know about you guys, but its often that way; an assumed challenge (because you spend so much time fretting over the issue --analyzing it, working it out in your head) once tackled in the flesh quickly reveals itself to be a simple, quickly performed chore. I started in at ten this morning, and by four this afternoon, had the rotor ring glued in place, and a loose interference fit between the ring and shroud groove achieved. Planning is everything, they say. So it was the case with this chore.

The only liability to working with Renshape 40 is the materials terribly abrasive nature -- it will dull carbon-steel tools in no time. Case in point are the four wood turning tools above, they required constant re-sharpening and touchup as I worked the PJ parts on the wood lathe. What you're looking at here is a neat little 'precision' grinder wheel available at Harbor Freight (damn, them Chinese make some neat tools!). The initial sharpening is done with a big ugly course wheel on my bigger grinder in the shed. The small machine here is for final dressing and touchup de-burring.

Hey! ... do public schools still have shop class? Or do they only teach that pussy CAD/CNC stuff nowadays? Am I to be among the last true Machinist's alive? Will the world one day be populated only by capable robots and their servant human keyboard entry/bit-changers?

God, Damn! ... What's happened to the Craft!

Here, finally, the full up pieces that make up the masters needed to produce 1/48 PJ parts for a SEAWOLF class r/c submarine.

Today's work was cutting out a ring to attach to the rotor, and machining out an interference fit groove for the ring within the after shroud. I wanted to keep the ring-groove fit a tight one to insure near perfect alignment as I performed the trial fits between the various subassemblies.

Trial fit of the rotor within the ring, and the ring within the after shroud groove. only after securing the ring to the rotor with CA adhesive could I slog back out through the backyard to the shed, remount the after shroud master onto the wood lathe and machine the groove another .003" deeper and wider, to afford the clearance needed for the rotor-ring to swing without making contact. Ironic that I should be doing such work on a wood lathe -- but, with care, you can achieve some pretty good moves ... if you keep the damn tools sharp!

Damn, I'm good!

Using the forward shroud securing flange as a reference, I rotated the friction fit rotor and ring around and made adjustments till the ring traveled without any noticeable wobble. I then applied thick formula CA, with a stick, to the blade tip joints and let it flow, forming a tight adhesive fillet between each blade-ring union.