I tried to drill out the flood holes on my older U-505 and the results weren't that great. I used a dremel at lowest speed with a small drill bit. Once the hole (or couple) was done, with the drill inside, I continued to enlarge the hole horizontally. Some of them came out alright and others not so well. Since I'm sure there are better techniques than mine, I would appreciate some help.
Thanks.

I'm pretty sure that drilling out any hole in styrene plastic is probably about the same, whether it's perfectly round or shaped. My experience is (and you won't like to hear it!) is that using the Dremel, regardless of how slow the speed winds up "melting" the plastic. Now that could be due to the bits not being perfectly sharp, but regardless, when I drill in styrene, I will always use a pin vise with the bit of the appropriate size and drill out by hand.

If the hole isn't perfectly round, I'll use one (or more) of my collection of "rat tail" files, to shape the hole. It may require a round one or a flat one or what ever.

For larger holes I may put several drill holes and expand with either a file or perhaps using my trusty #11 Exacto blade to carve out as much excess material as I can, and then finish the job with the files.

Bear in mind, I've never taken on the task of the flood holes on a sub, and I can appreciate that would take a long time!!

If you're finding that you can get most of the initial opening done with the Dremel, I'd keep using that, but I'm betting that you'll be happier with the results if you finish the job with a file.

Tom

Thank you! I just ordered a set of files among other things. Patience unfortunately is on backorder, but they're working on it.

Last year I did the 72nd scale U-boat I drilled out 128 flood holes. I don't have quite as much patience as Tom. I used a dremel and a little filing. With that many holes it would have taken a month instead of 4 days In all honesty, you have to look close to find any that might be a little overdone

Tom, has the basic method pegged. You might be able to pick up the small files at auto parts or small hardware (not the big boxes) stores.

If you need "More Power" look into cordless Dremel tools, mine's worked good on some small parts. they seem to run slower even if they're spec'ed the same.

My daughter came up with a rotary tool powered by 2 AA batteries. I think she got it at a beauty supply store for fingernail polishing. It's not too bad, but there's only one size collet and no way to tighten it on smaller drills.

Micro Mart sells an ajustable chuck that fits in a standard collet. no more messing around looking for different size collets. it fits the TAMIYA drill which does turn slow enough to drill plastic without melting it. if its still to fast take out one of the batterys and put in a dead one. thatll realy slow it down. the micro mart chuck will hold bits down to#78 they also sell a sub miniature chuck for even smaller bits #79P both chucks are around about $10 each well worth it for drilling out port holes.

I use a dremel too. To keep the plastic from melting I make sure I have a new sanding bit and I keep the dremel moving around. If you stay in one spot too long, it will melt the plastic. Just keep it moving. Then, I clean up the holes with the #11 x-acto blade. I can get the whole boat done in 2 days.

Take Care,

Jess

I used a slightly different method on my conversion of the Revell Lionfish to USS Jack (SS-259). I used the Dremel on the back side of the hull to thin the plastic before starting the drilling and filing. I like the more in-scale look of the thinned plastic and found it made fling the limber holes to the proper shape much easier. I also liked the comfort of knowing that I couldn't mess up things that might be visible if I slipped with the Dremel.

Which U505 are you doing?

After you drill out ALL of those drain holes, what do you do to 'hide' or cover the emptyness of the hull below the holes???

Jack was built by Electric Boat, so there weren't all that many individual holes to drill. I also did open the long drain channel along the superstructure using the same method - thin from the inside then open from the outside. I built in a false pressure hull and framing along the length of the boat and also used styrene to represent the bow ballast tank so there was no "emptiness" to see through. I tried to scratch build the wood decking from basswood strips, but gave up and used the Nautilus deck instead - their deck is pretty nice, but I am going to try the scratchbuilt decking again for the DDD2 build.

Thanks, but I'd still like to learn more. I have a couple of Lionfishes in the stash. The first one is glued up with the holes un-opened. I'm working on the Natilus early war superstructure for it. I'd like to go all out on the other one but don't have a clue on simulationg a pressure hill.

Sorry I don't have any while-building pictures, but this is the basic idea. For reference, the fleet boat pressure hull is just a series of cylindrical chambers. There is a diagram here (at the bottom of the page):

http://www.maritime.org/fleetsub/chap1.htm

Because the framing for the superstructure and outer hull would be visible through the open limber holes and long drainage channels I started by putting in "framing" along the sides of the hull pieces. I represented this with pieces of 0.010 styrene strip glued perpendicular to the deck. I had intended to follow the original framing scheme (roughly 24") but ended up doing every third (about 3/8" in scale).

The bow ballast tank would be visible through the foremost vents (the ones already opened in the kit) so I slipped a wedge of styrene to which I had cemented a back and top scribed to the hull in into the bow. I almost forgot to paint this before I put the hull sections together (duh). I did paint the frames from the inside as well. I posted some pictures in my gallery but its hard to see the detail, I'm afraid.

Once the hul was together I just fit another piece of 0.010 styrene along the inside of the frames to represent the visible part of the pressure hull. If you wanted to get really detailed, you could also run air, fuel, and water lines beneath the superstructure - but that exercise would be tough at 1:178. I might try it when the Trumpeter 1:144 Gato comes out - the 1:72 Revell is too big for me, I'm afraid.

I also used the Nautilus "Bluefish" sail, though I found the resin deck guns difficult and ended up scratchbuilding the 4"-50 Jack carried at the time that interested me. The Nautilus photoetch is well worth the money in my opinion.

Anyway - good luck and I'm happy to try to answer any questions. I'm by no means an expert modeler but have made lots of mistakes that I might be able to help you avoid.

Barry

EDITED BY Skipper: Working link

I used DrDull's method of cutting out the holes too, it has many benefits: faster, easier, and gives thin hull around the holes, for a scale look. If you thin enough with the dremel, the "bottom" of the molded hole thins and almost disappears, requiring just a quick stroke with a #11 like Jess uses.

P-hull - yep, a bit of plastic painted dark and no one will know it's not real!