1/25 Type VIIC/41 Scratch Build.

[paul von braun]

Mylo - sorry to hear

Mylo - sorry to hear about the stern... still we learn from our mistakes.
With regard to the hull detail, I am of the opinion that some of the hull detail is positive (ie raised) rather than negative and should therefore be added to the master you are making now.
I reckon some thin plasticard would do the job, applied to what you have made so far.

Check out the type VII thread on subpirates:

http://www.subpirates.com/viewtopic.php?t=444

See the raised details? That said, it's your boat Mylo - I just like to suggest things that I think are good.

Did nobody read the bit about me going to the Bavaria film studios next weekend? That means the set of and the models used in Das Boot!!!!
You all want to see the photos I will take?

Paul.

[JWLaRue]

Ummmm, Mylo......

I'm not sure you'll

Ummmm, Mylo......

I'm not sure you'll want to hear this, but that doesn't look like the Atlantic bow. That photo looks like the same shape as the bow on the OTW Type VII hull.....which is the earlier version found on the VIIB and VIIC's......

-Jeff

[paul von braun]

Jeff, and there was I

Jeff, and there was I thinking that it did look like the atlantic bow!!
But having looked at these photos of U995, I'm not sure what to think.







Paul.

[JWLaRue]

Yea, it's that upward and

Yea, it's that upward and outward sweep near the top of the bow that makes me think it might not be......

I think it'll be easier to tell once the hull has a coat of paint on it.

The Atlantic bow is more.....bulbous looking.

-Jeff

[mylo]

Gents.

I figured there might

Gents.

I figured there might be some comments on my "Atlantic Bow".

First off, Jeff, ....please ....NEVER hesitate to point out something that you think is a flaw. I appreciate the feedback and would WAYYYY rather fix something early as look at it over, and over, and over again on a completed hull. Believe me, if I found out all of a sudden that sucker was wayyy off.....out would come my hack saw again.

Paul, I stared at those exact photos for a long time, printed them out, and had them beside me to reference when I shaped the bow. That first one was the best one I could find showing the shape.

The photo that I posted on the thread of my bow does not accurately show the work I did on it. ...it's just....distorted in the pic somehow, the lighting is off.....something....I don't know, ...but it doesn't quite look like what I have. I feel I shaped it pretty close but may have defined the lip at the top a little too much. I'll be taking a closer look after I glass it, fill and work it with bondo putty if need be, but I don't think it will take a ton of work to iron out. If I don't get it exactly right on the money, I'm OK with that, as long as it "kinda looks" like an Atlantic Bow, or at the very least, looks different than a standard VII, which I feel it will.

As for details, all the hull details, male and female, will be applied to the glassed plug, and not just the painted foam, which is all I have at this point. I absolutely love the fine detail on Jeff's OTW boat......who can I get to stick on 10,000 1/25 scale rivets on this thing ? $1.25 / hour is what I pay.

More to follow.

Mylo

[JWLaRue]

Mylo,

Oh, good.....I'm never sure how

Mylo,

Oh, good.....I'm never sure how folks will take questions/observations like that.....

Here's a photo of the bow of my OTW Type VII during the build process. You should be able to see where the bow is 'pinched' in from the area of the waterline up to that riveted reinforcing strip....and roughly halfway between the tip of the bow and the anchor well.

On an Atlantic bow boat, this area is convex instead of concave.....



-Jeff

[paul von braun]

Mylo - I'm not sure

Mylo - I'm not sure I follow you. As I understand the process of GRP moulding one makes a master - which is what you have at the moment. Then a female mould is made from the master. From this the final, finished, mouldings are made.
If you put the details on the inside of the female mould then the detail would be 'negative' as it were.
Or - are you making a female, then a male (to detail), then another female of that with which to make the finished hull from?
What sort of stuff is this 'mud'?
Interestingly, as I remember GRP mouldings from my days as a design student - the plug was usually made from a wood such as Jelutong (due to its uninteresting grain, making it easy to work), sanded & sealed to within a thou of my life and then polished with carnauba wax. Release agent then painted on this followed by gel coat and then the actual lay up of the glass, carbon or whatever we were doing.
Are you planning on sealing the plug before you start your lay up?
As for detail, the OTW boat has, oh, 30000 (ish) rivets on it. That would be a true labour of love. If it were me I think I might just stick to the plate detail, reinforcement lines etc.

Paul.

PS I can certainly see the correlation between the bow shot I posted earlier and your plug, rather well in fact!

[mylo]

Jeff,

The more I look,

Jeff,

The more I look, the more I agree with you. As I have my bow now, it's flared at the top, but overall it's too "pointy". I'm in the process of reworking the bow. Once done, I'll take several angle pics and post. Please give me your feedback. Honest feedback on how to make this thing as good as I can is what I'm looking for. You won't hurt my precious ego. Let me put it this way, I DON'T want to hear critics coming out of the woodwork when I get this boat in the water.....NOW is the time to pick this thing apart, while I can still do something to correct it. It's all in the name of making a better model as far as I'm concerned.
Back to this bow, I've looked over every photo and diagram I can find but am having a bit of trouble visualizing the 3d look, sometimes it's hard to tell......like in this case, for me anyway. I need it in CAD.


Paul,

I don't feel that what I have now is a master. It's a foam plug covered with some dry wall (sheet rock....or whatever it's called in Europe...the stuff that we build interior walls with here in North America. I'm using the "mud" that is used to fill the cracks) and then painted to protect it from the resin. As it sits now, the painted foam/mud won't hold any scribed "female" detail. Once this thing is glassed, it will be a male master to which I'll add details for the casting of the female moulds, just like you mention. I hope I've got it straight anyway.

Ohhh.........and as for the studios in Bavaria....it goes without saying that all of us here at Subcommittee just simply EXPECT you to take lots of pics and post them when you get back, especially of the miniature models. It's just one of those things that doesn't even need to be said. ....if I'm ever in Bavaria......

Mylo

[mylo]

Step 27 ]

The entire foam

[b]Step 27 ]

The entire foam / sanded mud hull was painted with an Enamel Urathane paint (The stuff is actually for garage floors, which I had left over. It's very heavy duty stuff). This is done to protect the foam from the resin used in the glassing process. Steve Neil had an excellent suggestion to use Epoxy instead of the resin, but I had already bought a bunch of the stuff.....and it wasn't cheap. That, along with the fact that I had all this paint kicking around, made me decide to seal the foam with the paint prior to glassing. Coincidently enough, the paint is "Slate Grey", ....which is quite suiting for a U-Boat hull If I was to do it all over again, I would likely use the Epoxy if I could find it, depending on availability and cost. The thought of a melted foam plug does not sit well with me. There will be several coats of the sealer paint applied before glassing, making sure that EVERY part of the hull is covered and protected. I tested this sealer paint theory on a scrap piece. It worked without any problems.

[b]Step 28 ]

What I thought was going to be a 5 minute scuff of the first paint coat turned into an hour long sanding session to get the runs out from the first coat, which I apparently applied just a little too liberally. Just one more example of things taking longer than expected. There is sure to be much more of that in this build. After the sanding / scuffing of the first coat, the second coat of Enamel Urathane paint was applied. This stuff is really giving the foam / sanded mud hull a hard shell and should make for a real good sealer.




[b]Step 29 ]

I had almost overlooked a detail of the upper deck, that being a small lip that protrudes out away from the lower wintergarten. I discovered this lip in one of the photos of U995 that I was looking over. Just when you think you have paid attention to all the details, you haven't. This was an easy fix at this stage. I molded a couple "lips" out of MDF and glued them on the side of the now painted hull. They will be painted in the 3rd sealer coat. Since they are MDF, it is not crucial that they be protected from the resin and so the one coat will do.





More to follow.

Mylo

[mylo]

Step 30 ]

It was time

[b]Step 30 ]

It was time to get at the tower. I hadn't put much thought into how I was going to go about it, until this point in the build. I figured that what I needed to do was cut the tower part of the top down view plan out with a hobby knife and then make photo copies of it, as I would need several templates to complete the entire tower. I was reluctant to hack into my nice intact plan, but I eventually figured that plans are supposed to assist in building the boat, not be some artful drawing to gawk at. After thinking it through and concluding that cutting the tower portion out wouldn't be a huge mistake as I still had the side view to make any measurements with, I cut away. A quick trip to the office and I had 10 copies of the tower top down diagram to use.



The first thing I did was cut out a template that covered the lower wintergarten deck right through to the lower portion of the tower, all in one piece. I would make the entire conning tower out of the extruded foam, cover it in mud, sand, and paint, much like the hull, except without the need for the hardboard formers. I needed this bottom piece of foam to be 1 7/8" thick according to the plan. What luck, the exact thickness of the pink foam. I traced from the template onto the 1 7/8" pink foam and then cut out with the band saw, sanding up to the line with the 1" sander, just like in the building of the former masters. I then used this cut out and shaped piece as a template to draw another outline exactly the same. I would use this second piece as the second wintergarten / tower deck.






This second deck needed to be 1 3/8" thick so I had to sand 1/2" of thickness off. Once sanded to 1 3/8", I had to now cut off the excess lower wintergarten part, making the shape that was needed under the 2nd wintergarten deck. I had to reference many photos and even pics of models to figure out the exact shape that was under the second wintergarten as it is not depicted in my plans. Using a template to get the same curvature on both sides, I drew the line on the foam where I needed to cut the foam and then cut it out with the band saw. After cutting it out, I had to give it the special shape that it has by sanding it by hand very carefully. The shape is more eliptical at the top near the 2nd deck, and more "pointy" at the bottom at the main deck. A little sanding.....eye ball it.....more sanding....eye ball it.....look at photos, contemplate.....more sanding....eye ball.....look at different photos. That was the process. After the upper section was shaped, I shaped the lower wintergarten section as it too has a taper to it as it meets with the main deck. The same exact process was used for the lower wintergarten shaping as the upper one.



Once I had the two pieces shaped, I glued them together, clamping them in place so that they didn't move as they had to remain lined up perfectly. After the glue had dried, a layer of mud was applied. After the mud had dried, it was sanded.




[b]Step 31 ]

I decided that I was going to mould the splash guard right into the tower base piece for the casting of the final part. Like everything else, the plans were used to obtain the dimensions, which were traced onto MDF, which was cut / sanded to shape. Due to the complexity of the shape of this piece, it took some time even though it was small. The splash guard was then glued to the tower base piece. You will notice that on the type VIIc/41, the splash guard does not go all the way around the conning tower due to the antanae enclosure on the port side of the tower.








[b]Step 32 ]

The main tower enclosure was now made by laminating 3 pieces of 3/4" MDF together 6" x 4". Out of this big block, only a narrow piece would be cut but it was required to have all this material to get the piece that was needed. The template was cut from one of the photocopies of the tower section and spray glued to this block. Once dried, the piece was cut out with the band saw and finished with the 1" sander. There was a lot of measuring and precision having to go into building this piece which really consumed the time.




[b]Step 33 ]

Templates were made for the upper and lower wintergarten decks out of 1/8" hardboard. From these templates, the deck pieces would be made thus ensuring exact dimensions given multiple copies. As well, these templates would be used to make the upper and lower wintergarten railing jigs. (See Step # 37 to follow).




More to follow.

Mylo

[paul von braun]

Mylo - I think what

Mylo - I think what we call that filler in the UK is 'pollyfilla' a gypsum based, water mixed stuff.
Dont forget that whatever imperfections are in the plug will be reproduced in anything you mould with it - it is therefore imperative get the surface perfectly smooth at this stage.
I guess you could get down to a really fine grit and then use some really fine wire wool. I think it will also pay dividends when you come to remove the plug from the female mould.
The other thing is that in my humble opinion, you could/should use epoxy at this stage since it will definately not affect the foam - the polyester can be utilised later on with the mouldings. Your call though.
The other thing to remember is that it always takes more resin than you think - and you do have the conning tower to o as well.

Paul.

[mylo]

Paul,

That's not a bad

Paul,

That's not a bad call.....getting the Epoxy anyway and using my resin for my MDF only pieces. I've got a lot of it but......well.......I'll likely build other subs too so....

Any guesses on how much Epoxy I would need to do this hull and tower ?

I understand the need for the plug to be flawless. It will be....well...as close as I can get it anyway. After I glass the foam, I will be spending a ton of time getting it smooth and as perfect as I can. I have autobody filler putty that I will be using once the foam is glassed and will be working the sanding grits down to fine, fine, fine. I never thought of the benefit that would have in removing the plug from the female mould, but yes, for sure it will help.

We have Pollyfilla here in North America too, and this stuff I'm using isn't it. It's close, but this "drywall mud" is soupy...kind of, like mushy toothpaste or something. I bought it already mixed in a 5 gallon (20L) bucket. Maybe if you made a batch of Pollyfilla that was runny.....that would probably be very close.

Mylo

[JWLaRue]

Mylo,

I like your solution for

Mylo,

I like your solution for making the upper walls of the conning tower......a very good representation of the prototype's thin-wall structure.

She sure looks good with that coat of gray paint on, doesn't it!

You mentioned the protruding lip at the main deck where the aft Wintergarten is located on the U-995....which reminded me. I'm certain that you already know this, but be careful with using the U-995 as a basis for a WW2 Type VII. She has been heavily modified since the end of the war. (and 'modified' is in some cases a polite way of saying it) Finding photographs from WW2 are a good way to make sure that it should be there.

(I'll see if I can find any of the U-995 that show that lip.)

-Jeff

[davietait]

Here's 3 photo's I took

Here's 3 photo's I took of U995 I do have more but can't find them at the moment.




for some reason the subcomitte server doesn't show the images at full size so right click and use view image and you'll see the full size images

Davie

[mylo]

Davie,

Thanks a lot for

Davie,

Thanks a lot for those pics. I need all the reference I can get when it comes to that Atlantic Bow.

Jeff,

The "lips" are represented on my plans as well as on photos of U995. I did realize that U995 has been modified from it's days with the Norweigans, but I don't know how. I'll be doing some more research on the lip thing to make sure. If they were an afterthought by the Nords, I can remove them quite easily at this point. I'm not building U-995, just a VIIc/41 so I want to be careful not to put something on my boat that is a U-995 "custom" piece. If you know what is customized on U-995, please fill me in. I've been using the current photos of U-995 quite often for a reference.

Yes, I like the thin wall of the conning tower enclosure, the wall thickness of course taken from my plans. Once I get all the odds 'n' ends put in the tower, I think it will look pretty good. I had to be quite careful not to break it when I was making that piece. I had a little drum sander that I put in my drill press that was exactly the right size to sand out the inner curvature, which was handy to say the least. A variety of sanding tools, both power and hand are a must.

As for the grey paint, yep, not hard to visualize what the final boat is going to look like.

Mylo.

P.S. I'm still working on reshaping that bow. REAL glad you pointed that out at this stage.