Topic: Salt Water Darnell U37 (Read 81472 times)

unbuiltnautilus · « **Reply #75 on:** July 16, 2013, 04:35:28 pm »

M5 csk bolts now fitted, along with the upper soft seals.
The copper wire in the slots of the bolts helps to prevent the bolts spinning loose in the future when tightening down the hatches, a common submariner trick. mind you, epoxy in the thread as you wind them in plus more on top afterwards, should hold them in...

unbuiltnautilus · « **Reply #76 on:** July 16, 2013, 04:41:19 pm »

As the hatches start to look better, the watertight compartments are looking a little worse for wear. A bit of controlled chisel action has resulted in a large amount of poor quality epoxy and paint flakes coming off. Also, I have managed to remove what looks like white Sikaflex from some of the leak points. to be replaced with epoxy re-enforced with fibre filler powder, once all hull to bulkhead joints have been ground with a drill and burr.
Removing the old flange will also allow me to remove some of the now surplus plumbing parts that litter the model. One visible alongside a pushrod outlet tube.

unbuiltnautilus · « **Reply #77 on:** July 31, 2013, 05:19:50 pm »

Bulkheads now re-enforced with an epoxy/Glass Fibre Strands mix. Applied, warmed up with a hot air gun, run round the bulkhead and left to set. The new upper hatches are bonded on with Glass Fibre Repair Paste, trimmed while 'green' and finally sanded back to a clean edge 24 hours after first bonding.

unbuiltnautilus · « **Reply #78 on:** July 31, 2013, 05:23:14 pm »

And concerned about the uncontrolled decent to the bottom of the test tank on its first float, I have added EPO foam bouyancy in strategic locations around the model. I dont think I have enough aft yet and am considering fitting an arm band around the outer hull if all else fails

.

unbuiltnautilus · « **Reply #79 on:** July 31, 2013, 05:35:06 pm »

Now I have to show some level of patience unknown for me. We have a display this weekend, so I cannot set up the test tank till Sunday week, fine, I will think of something to do in the mean time. Maybe get some filler out and make good the damage caused by the angle grinder, sounds like fun....all that dust....whats not to like?

Netleyned · « **Reply #80 on:** July 31, 2013, 05:45:26 pm »

Sounds like a very dry and dusty job.
After all the sanding you would deserve
a pint and a juicy pie.
Still and West springs to mind.

Ned

unbuiltnautilus · « **Reply #81 on:** August 01, 2013, 09:15:24 am »

Their 1980s pork pies will live on in my memory forever.

unbuiltnautilus · « **Reply #82 on:** September 17, 2013, 06:19:54 pm »

A month and a half on. Dusty work complete, paint on, almost ready for the test tank again.
First the making good the damage caused by the angle grinder. I prepped the hull with a drill and dental burr, after first degreasing with acetone.
A balsa strip was bonded between the outer hull and the soft seal and acrylic of the removable lid. This was sacrificial and kept the fibreglass repair paste away from the shiney posh bits! Once sanded, it could be chiselled out. the upper hull was treated to some hand cream as a release agent and it was time to slap on the paste..

unbuiltnautilus · « **Reply #83 on:** September 17, 2013, 06:24:41 pm »

Following this, the latest sand down of the by now ruined camouflage and paint job, I decided to start again. New bottom colour, which turned out to be just a little too glossy for my liking, then abused with my favourite Scotchbrite pad. This time I was not happy with the look so some subtle work was required with a can of Humbrol Matt Varnish, all over the lower hull..

unbuiltnautilus · « **Reply #84 on:** September 17, 2013, 06:30:51 pm »

Then I proceeded to cut in the above waterline colour. As the model was going to represent a U-Boat returning from patrol, it could look a bit scruffy. This started with my cutting in of the mid-grey colour. This was applied in a strictly patchy nature, just covering any obviously sanded down areas, not anywhere else, where the already patchy look would add to the final finish.

unbuiltnautilus · « **Reply #85 on:** September 17, 2013, 06:35:31 pm »

Painted the '88'.
Then pencilled in the new camouflage pattern, followed by a stipple of Maskol masking solution, latex based pink liquid, to represent chipping on the camouflage. You paint over it, then peel it away revealing a random pattern showing the base colour through the chipping.

unbuiltnautilus · « **Reply #86 on:** September 17, 2013, 06:49:24 pm »

Rust. I love my rust. This time I was going to try Humbrols new weathering powders. These are available in a number of colours and are eminently unsuitable for use on a model that goes under the water, washing all the powders off again, so, fine then

.
Making them useable for the marine environment entailed a 50:50 mix of Humbrol Mattcote and a suitable thinner, once mixed and shaken up, I then added small amounts of powder to the mix, till I had a colour somewhere between seaweed and rust. testing it showed that i had to work fairly fast as it tended to dry quicker than I expected once applied to the model.
An unexpected bonus from using different colours from the range, when left overnight, the colours partially seperated in the pot. This gave me more than one colour to use, depending on how deep the paintbrush went into the mix, excellent!
On the conning tower I placed some of BECCs U-Boat insignias, more for the little bit of colour than anything else. My mixing of U-37 with the 10th U-Boat Flotilla and Erich Topps boat would surely go unoticed? Except by the first person to see the model...so all change!

unbuiltnautilus · « **Reply #87 on:** September 17, 2013, 06:57:41 pm »

The problem with rust, if you dont deal with it, it just gets worse...

The rust is either streaked down the hull wet, with a very fine brush, or applied a little more broadly and dabbed off with a tissue. The end result shouldn't look too much like a 'brush job' or a 'spray job'. It should be at least a little difficult to tell how it was accomplished.

unbuiltnautilus · « **Reply #88 on:** September 17, 2013, 07:08:19 pm »

The last few photos show the new 9th U-Boat Flotilla emblem of the Laughing Sawfish and a Stag on a plaque on the front of the conning tower. I knew this would be useful when I bought if from Games Workshop 20 years ago, and I was right.
It also shows where I overdid the rust on the front of the conning tower, this was remedied in the last photo by dry brushing the original grey colour over the rust, not just on the conning tower but elsewhere where it was a 'bit too much', blending in any obvious bits that offend my eye.
All that remains is a little bit of Humbrol Chocolate Brown to darken small 'edges' of rust, to give them that deeper corrosion look. Its also about time to get it wet again, RC is re-installed and its almost ready to dive

bat44 · « **Reply #89 on:** September 17, 2013, 10:16:23 pm »

so when are you going to do my barge for me then

unbuiltnautilus · « **Reply #90 on:** September 18, 2013, 09:18:07 am »

Quote from: bat44 on September 17, 2013, 10:16:23 pm

so when are you going to do my barge for me then

You're big enough and ugly enough to do a good job of it on your own

bat44 · « **Reply #91 on:** September 19, 2013, 12:22:13 am »

unbuiltnautilus · « **Reply #92 on:** September 24, 2013, 06:08:57 pm »

Sunday was test tank day. However, following re-installation of the equipment I found the Action Switcher was not switching tha air bag pump. Through a process of elimination I found that the Tx mod I had carried out was causing the problem. Without a clean 'mid-stick position' signal the switcher got the hump and wouldn't play. upon checking the Tx I found I had cut corners fitting the buttons for dive and surface, neglecting to fit any resistors in line, but tapping straight off the board...naughty.
So in went a 10k potentiometer in line and everything was fine.

unbuiltnautilus · « **Reply #93 on:** September 24, 2013, 06:13:58 pm »

At the test tank the good news was that the seals were 95% good with just two small leaks to address, also the front of the sub floated nicely, however the back of the sub sunk

. Still better than a poke in the eye with a sharp stick!

Much tea in evidence at the test tank, good for thinking is tea...

unbuiltnautilus · « **Reply #94 on:** September 24, 2013, 06:18:59 pm »

Never one to miss an opportunity. Back in April 2011 when I started this project ( No rush

), I took a photo before the work began. It seemed right to take a second photo as she is today, from the same position, resplendant in rust..

U-33 · « **Reply #95 on:** September 24, 2013, 06:23:05 pm »

That looks nice, love the weathering job! Just don't show Ben, whatever you do...

unbuiltnautilus · « **Reply #96 on:** September 25, 2013, 09:19:09 am »

Cheers

. First leak now sealed, second one identified. Next job, cutting up more foam for the upper structure. It will float on an even keel, whatever it takes.

unbuiltnautilus · « **Reply #97 on:** October 10, 2013, 02:26:33 pm »

Pressure tested the model out of the water. lost most of it over about 60 minutes. I checked it this morning using soapy water ( if it works on my bike tyre, it should work on a U-Boat..), air was escaping from round the bolts through the perspex. I am currently using fibre washers under M5 nuts, have just purchased 50 off M5 x15mm Stainless Steel washers as an alternative to the fibre washers, thoughts??

surfs up · « **Reply #98 on:** October 10, 2013, 03:16:48 pm »

Use both

U-33 · « **Reply #99 on:** October 10, 2013, 03:18:47 pm »

Miniature O rings, maybe?

News:

Author Topic: Salt Water Darnell U37 (Read 81472 times)