Akula 1/144 Scratch built

[bwi 971]

The sail still has to be scribed.

The mobility of my arm is FINALY improving, scribing is not yet on the menu. But I managed to get some stencil prep, I can do small stuff but I must do it in small steps, more breaks than work. But there are 24hr in a day and most of them I’m awake.

The method making GRP laid up stencils and marking all the stuff on them does not suit me. I’m not good at it, a man have to know his limitations, and needs a lot of practice.

So I developed my own way that suits me well but is more time consuming (says the man who uses epoxy as a cast resin, which takes 7 days to hard out). I make flat stencils and bent them around the model. But there is a catch.

First I made a copy of the drawing. The sail in top and side view. Both were cut out.

As the sail model is 3D and the drawings are orthographic views you have deviations when you bent the paper cutouts around the sail of your model.
Never the less I do it because I want to know where the deviations are and what I have to do to correct them.

Here the GRP made laid-up stencil of the sail I made previous but didn’t use came in handy. I used it to squeeze the paper cutouts nice and tight to the sail.

As an example the sonar dome on the aft part of the sail it is drawn as a straight lateral line in the top view, but when you bent it around the sail it deforms into a curve, and you don’t want that. So the solution is you have to draw a curved lateral line on your flat stencil. So it becomes a straight line once you bent it around your model.
You will also have misalignment's between the different paper cutouts that also has to be addressed.

Based on the paper cutouts I have drawn everything on a paper sheet making adaptions on the way. (corrections from foto’s, curves, positions).
I glued the paper on a 0.5mm styreen sheet to make a test stencil, cut, milled, filed, punched all openings into it.

Need to do some minor adaptions, as indicated on one of the pictures below, I have also indicated the aft sonar line/curve I mentioned above.

Next up will be the side stencils of the sail.

Grtz,
Bart

Paper cutouts


Sceeze tool


Test stencil


Stencil cut into different parts/layers


Used the stencils to see the result, noted along the way I need to make some adaptions for positioning the different stencil layers, hatch need to be allocated in a different stencil layer.






Here are example of adaptions to be made and the curved line

[trout]

Before you do all that, blame the website. It is possible it is in the uploading there is an issue. I have also run into if I take too long to post, the very same thing will happen as what happened to the posting you made. You could edit your post, replace the photo or re-upload the image. Try just a few at a time and save. Go back and edit to add more and so on.

[bwi 971]

I need to have a new computer......I think this one is reaching crush depth, It is even slower than me.

But to keep peace with "she that must be obeyed" I think it is better I will start from scratch, work from the bios onward, reinstalling windows, and hope for the best......and score some points......I think I'm in the negative for the moment........I just was informed by "she that must be obeyed" that I must change "think" into "definitively".

I will post them again Tom.

Grtz,
Bart

[trout]

No pictures in the last post.....waaaaahhhhh. Me want pictures.

[bwi 971]

Almost run out things to do (and can do) while waiting for the epoxy to hard out.

Made the saddles for the SD. The saddles are made of 9mm styrene sheet (3 pieces of 3mm glued/melted together).
I will provide some hooks in the saddles to keep the SD pushed in the saddles with rubber bands, yep that's why they are 9mm wide, need some flesh to screw the hooks in.

They are both provided with a recess, to prevent the longitudinal movement of the SD, and when the SD is placed in the sub it will always sit in the same position.

As my SD is hanging, the saddles are partly above the water in surfaced condition. So I needed to keep the weight of the saddles as low as possible. The lift capacity of the SD is limited, I previous calculated I have some spare but I need to keep things light above the waterline. That’s why I drilled some holes in it, 25 gr (0.88 oz) together, not bad at all.

To let prevent air pockets when diving I provided some channels on the edges of the saddles. One suggestion drill the holes before you cut out the desired shape of the saddles else you will not be able to drill those holes i.w.o. the edges.

And YES I thought about it before I made the cut, seems I’m not so donkey after all.

Grtz,
Bart

[bwi 971]

I certainly am taking it in. It is appropriate timing for me as I plan on doing some part casting this summer. So, casting with bearing in is a nice touch. I must have missed the part of what you used to cast with that takes 72 hours to cure (certainly a great work time to vacuum and pressure cast!).
Peace,
Tom

the curing time came in handy now .....for the moment I'm captain slow.......but futurewise I will use the 3-4 minutes one LOL.
Grtz,
Bart

[trout]

I certainly am taking it in. It is appropriate timing for me as I plan on doing some part casting this summer. So, casting with bearing in is a nice touch. I must have missed the part of what you used to cast with that takes 72 hours to cure (certainly a great work time to vacuum and pressure cast!).
Peace,
Tom

[He Who Shall Not Be Named]

David I'm using epoxy now.....found a polyurethane resin in the same shop 3-4 min curing time.....I feel like a donkey.

Grtz,
Bart

Not at all, Bart. When I first started out with casting you would not imagine the bizarreo-bull**** crap I first used! Live and learn. Lov'n your work -- very good stuff, sir.

M

[bwi 971]

David I'm using epoxy now.....found a polyurethane resin in the same shop 3-4 min curing time.....I feel like a donkey.

Grtz,
Bart

[bwi 971]

I know it went over the top with the bushings......but after college when I went sailing I was lucky to be re-educated on board by old school engineers (good behavior and good manners went down the drain also) ...they are the reason that it became my natural behavior to try to make things sailorproof (never succeeded though, I learned we can only attempt to make things sailorproof).

Additionally the root bushings in the diving planes and rudders are protruding and act as a center pin for positioning the planes and rudders on the hull, that is the intention will see if it turns out ok.

I will go shopping for Alumilite polyurethane casting resin or some kind of substitute THKS!

Grtz,
Bart

[He Who Shall Not Be Named]

You're encapsulating bushings into the resin parts. Slick! Overkill .... but slick. Resin makes fine bushings on its own. Excellent tool design on display here. Get some Alumilite polyurethane casting resin. Minutes, not days.

M

[bwi 971]

Had to split the WIP to make it work.......I will NEVER understand IT.

Today I have done the casting….....no leakages........……the vacuum casting worked well David, MANY thks for your explanation on that. After degassing the tool I placed it in the pressure pot together with the rest of the tools.
I have to wait some days to see the result (it takes 7 days to fully harden). Hope the prep work pays off.
The picture is showing the cores in place together with the bushings witch will be embedded in the parts.

Grtz,
Bart

[bwi 971]

Thks....probably because my daughter assisted me.

I did the touchup of the scribing lines (thks to Andy I found the right putty that does not affect the paint) ......time consuming but afterwards I was amazed with the amount of damage that became visible when it was filled with red putty (most of the damage were broken off paint chips around the edges).It’s was worth the effort.
I hope I can finish the scribing when I’m up and running again.

Grtz,
Bart

[bwi 971]

Thks George will post WIP again and delete previous.
Grtz,
Bart

[george]

Hello
Just to report, there are No pictures in Post 162 previous posts Yes pictures are fine.
George