1/12 Seehund build - LWB

[tifosi12]

I should have said, that of course the SD is in scale as well. That's not a 2.5" SD :) My point about the model is that experimenting in this scale is fast and cheap to figure out all the details and problems. Before I commit to 15+ hours of print time for each section I want to make sure that at the end I have pieces that fit together and support the functionality I want.

[tifosi12]

After some more printer trouble I bought another one (my 4th) and fixed #3. Now I have two printers going on 24/7 printing the parts of the sub. Fingers crossed I get a complete first set by the end of this week. Then we'll see how well or not the parts fit together. The CA glue Bob recommended is a life savior: It glues the stuff together stronger than the actual 3d print. How do I know? I had some misaligned parts and tried to tear them apart. The glue bond would not let go, the structure of the 3d print did eventually.

[SubDude]

That Starbond CA is excellent stuff. I used it to glue together my Columbia and it is holding up great through all the trips back and forth to the pool for trimming. I have been impressed with it.

[tifosi12]

That Starbond CA is excellent stuff. I used it to glue together my Columbia and it is holding up great through all the trips back and forth to the pool for trimming. I have been impressed with it.

Absolutely. As I said the boat I ripped apart broke within the 3D structure and not at the glued seals.

That said I did notice considerable differences in curing time depending on what PLA filament I'm using. Some take overnight whereas other bond within a few minutes.

[He Who Shall Not Be Named]

Absolutely. As I said the boat I ripped apart broke within the 3D structure and not at the glued seals.

That said I did notice considerable differences in curing time depending on what PLA filament I'm using. Some take overnight whereas other bond within a few minutes.

CA's cure quickly on chemically base (alkaline) substrates. Check the specification sheet of your substrate -- is it acidic or base? The higher the pH, the more quickly the Cyanoacrylate changes state from liquid to solid. (But, a slow cure is good -- deeper penetration than a quick cure)

High pH, good; low pH, bad -- if speed is your objective. Moderate pH permits deeper penetration of the glue to the substrate.



David

[tifosi12]

CA's cure quickly on chemically base (alkaline) substrates. Check the specification sheet of your substrate -- is it acidic or base? The higher the pH, the more quickly the Cyanoacrylate changes state from liquid to solid. (But, a slow cure is good -- deeper penetration than a quick cure)

High pH, good; low pH, bad -- if speed is your objective. Moderate pH permits deeper penetration of the glue to the substrate.



David

Thanks Dave, another great post I can learn from.

[tifosi12]

I figured it was time to give an update on this project. The picture shows the 1/24 model I printed to figure out the dimensions to take off on the top to place the SD. The printing of the 1/12 segments is coming along, although with the usual hickups. I'm using every role of PLA I have, hence the Italian Tricolore. By the time I'll be done there will be more colors, might be more like the flag of South Africa.

I'm sure Dave recognizes the SD. It was supposed to go into the XXIII but I abandoned that project. Hopefully this will be luckier.

[tifosi12]

At the risk of shouting some more into an echo chamber, here is a further update:

Got now almost all parts of the boat printed. Started to glue together the hull and it's starting to look good. Conning tower assembled and painted. Next up will be the critical bits of engineering some solution to access the business end of the boat. I don't like Oto's approach with tiny screws and nuts. I'm not a brain surgeon and my hands don't fit into any of those nooks and crannies to tighten those bolts. So CA it is instead. Which then leaves me figuring out a way to service the boat. My only redeeming quality is that I'm fairly good at the 3D CAD design and printing by now so I'm hopeful to come up with a tangible solution.

Below a picture of the conning tower before painting. Meanwhile I also replaced those "snorkels" with something more elegant and to scale.

[SubDude]

Looking good. I am almost to the point of printing the sail on my Seehund project. It has been over 2 months since I started printing it. I am ready to move on...

[tifosi12]

Looking good. I am almost to the point of printing the sail on my Seehund project. It has been over 2 months since I started printing it. I am ready to move on...

What model? Oto's? What scale? 1/12?

I run into a few hickups with the sail: Oto (for reason beyond my comprehension) leaves in plastic parts, that you are supposed to remove before assembly. Didn't realize that (although Bob makes a mention in one of his videos) and ended up trying to remove those pieces from a finished model. Another issue is the misalignment of the hatch and its hinge. So I'll probably skip that part and have the hatch closed. Before I glue that shut I'll take some pictures with the Captain and hatch open. And as mentioned already the rear snorkel (?) is not very well when coming out of the printer, so I improvised, but came out fine.

On a happier note: The water decals did survive a matte coat. Some decals crumble but Oto's just about made it. Not perfect but good enough to stay on under water. So that's one less worry for the rest of the boat.

Now for the real piece of work: Trying to add Dave's SAS snorkel into this thing will be interesting. I created a special housing which I will print today. Hoping that will work.

It's a long way to the top if you want to rock'n'roll. :)

[tifosi12]

Oh about the glass window on top of the hatch: Was worried that would fog over with CA but was careful and it did not. Question is now whether I should drill a tiny hole at the top to let out any trapped air.

BTW: The sail by itself is negative buoyant, just as I like it. Was worried about that too since I don't do 100% infill when 3D printing.

[SubDude]

What model? Oto's? What scale? 1/12?

I run into a few hickups with the sail: Oto (for reason beyond my comprehension) leaves in plastic parts, that you are supposed to remove before assembly. Didn't realize that (although Bob makes a mention in one of his videos) and ended up trying to remove those pieces from a finished model. Another issue is the misalignment of the hatch and its hinge. So I'll probably skip that part and have the hatch closed. Before I glue that shut I'll take some pictures with the Captain and hatch open. And as mentioned already the rear snorkel (?) is not very well when coming out of the printer, so I improvised, but came out fine.

On a happier note: The water decals did survive a matte coat. Some decals crumble but Oto's just about made it. Not perfect but good enough to stay on under water. So that's one less worry for the rest of the boat.

Now for the real piece of work: Trying to add Dave's SAS snorkel into this thing will be interesting. I created a special housing which I will print today. Hoping that will work.

It's a long way to the top if you want to rock'n'roll. :)

Oto's 1/16th printed at 1/6th. 78" long.

[tifosi12]

Oto's 1/16th printed at 1/6th. 78" long.

Ah, I remember. Running the 3d printer for a week to print one section. Was wondering how you were doing. Make mine look like child's play.

The good news for you is that you'll have enough space in the tail section to install the RC bits for rudder and dive plane. At 1/12 there is not enough space. At least not for my hands. I'm not a watch maker.

[tifosi12]

Oto's 1/16th printed at 1/6th. 78" long.

At that scale you could RC the torpedoes. They'd be about the size of a regular RC sub. Holy smokes!

[SubDude]

Yeah, I am just printing it for a buddy of mine. He will have to put it together. Bigger boats have their advantages and disadvantages. Seriously on the torps, we could just strap a couple 1/72 Type VII's under each wing. Lol!