Author Topic: 1/72 Hansa Brandenburg W 13  (Read 295 times)

Offline lone modeller

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Re: 1/72 Hansa Brandenburg W 13
« Reply #15 on: September 16, 2019, 07:34:09 AM »
Evening All,

Many thanks Rick, Dave, Ken, Terri, Frank, Ian and Roberto for the very encouraging comments which you have left.

Dave: I will continue to provide scratch build projects in God's Own Scale but I have to state that I do have a larger scale project on my list so there will be a hiatus at some time in the future!

This has been a week in which I have been learning some dark arts in the use of an electric drill, (ie a Dremmel) on laminated plastic. I decided not to try to mould the upper decking of the hull as this would have meant carving a mould from basswood and then trying to push mould a piece which would sit exactly on the curved upper hull sides. I could see clearly that much frustration and wasted plastic lay on that route so I opted instead to do what I had done on the H-B CC and make the upper decking from laminated plastic. I made one piece which would sit comfortably over the gap in the upper hull:



A centre line had been drawn on the top of the new hull piece to help me to sand the correct curvature in the nose area and to make sure that the piece was properly centered on the hull. However I did not measure the thickness of the top correctly, and despite adding what I thought was adequate extra card to correct the problem I found that I still did not have enough depth and to avoid unsightly joins on the finished upper decking I decided to scrap the piece and start again.

This time I got the thicknesses right so I went ahead and scribed with a pair of dividers where the gunner's cockpit would be and traced and scribed the outline of the pilot and navigator's cockpit. However when I tried to drill out the gunner's cockpit I found that the Dremmel was so fast, (even on the slowest revs), that it melted the plastic and tore a larger hole than what I wanted! Time to make a third decking piece!

Number three was more successful: I was able to get the correct thickness and to drill holes ready to remove the plastic from the cockpit openings without gouging out an excessively large hole. I did this by drilling one hole at a time and stopping the drill to allow the bit to cool between each drilling individual holes. I also cleaned off any plastic which had stuck to the bit and made sure that the holes were not to close to the scribed edge of the cockpits. Here are the two efforts with the failed second attempt on the left:



The holes were joined with a scalpel blade so that the centre pieces of plastic fell out and the the final shaping of the cockpit openings was completed with a round and half-round file. A long and somewhat laborious process but as I learned the hard way, one which cannot be rushed.



With the cockpit openings complete I added some basic cockpit details - seats, a control wheel, a panel between the pilot and navigator seats and a seat for the gunner. Very little of this will be visible on the completed model and I do not belong to the school of modelling which insists on adding details which will be forever hidden once the model is complete. I am happy to know that those details are missing and wish to spend more time on getting an accurate outline and detail which can be seen! I also filed the upper decking to the shape of the side profile prior to fixing it in place as this required some hard scraping which would have risked causing damage to the hull if I had glued it in place beforehand. In doing this I got a little carried away and took too much from the top of the rear deck and had to build this area up with filler - hence the large grey area in the image below. I also removed much of the excess plastic on the sides of the decking at this stage again to reduce the risk of damage to the hull sides.



The upper decking was glued to the hull and held in place overnight with the same state-of-the-art sophisticated equipment as was employed earlier to hold the hull bottom in place and described above. The centre line on the decking enabled me to get the accurate positioning for the cockpits relative to the rest of the hull. From the left (port) side the hull now looked like this:



Final shaping could now begin. First the sides of the upper decking were filed so that they were flush with the rest of hull sides and then the curved nose section in front of the pilot's cockpit was sanded to shape: I used a card template made from a cross-section diagram on the plans to achieve as close a match to the profile as I was able. The centre line and a cross line can be seen on theses images: the latter marked where the template was used to check the cross profile. You van also see the filler that I had to add to the hull sides below the decking to remove a small step caused by the thin plastic bending inwards when it should really have curved slightly outwards. I am hoping that none of this will show when the hull is painted and the wings are in place....





Having got the decking as I thought that I wanted it I checked the lower wigs against the sides of the upper decking - and found that in spite of the filler the shape was still not right....! So out with the file and remove the front end of the filler to the plastic below and glue into place a piece of 20 thou card. A file and glass paper were brought into action when the plastic was firm and the edges of the new piece of card concealed with yet more filler....



Now the wings fit without an unsightly gap. Still the hull is not complete however. I have made a fin from 60 thou card with two pieces of 20 thou card at the base. The fin of this machine was very wide at the base and tapered upwards so I had yet more filing, sanding and filling to do before it was finished:





Now I can add the gunwale along the sides of the nose and bomb rack strips to the front section of the upper hull, but more of that in a later post.

Thanks for looking.

Stephen.

Offline kensar

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Re: 1/72 Hansa Brandenburg W 13
« Reply #16 on: September 16, 2019, 09:32:40 PM »
Those Dremels can get you in a lot of trouble, and thank God for filler (putty).

I have a light dimmer switch wired into my single speed Dremel just to slow it down so it won't melt plastic.  I got this idea from Dremel themselves.  It will only work on single speed Dremel tools.

Its good to see progress on this - coming along nicely!
Ken M.

Offline RAGIII

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Re: 1/72 Hansa Brandenburg W 13
« Reply #17 on: September 16, 2019, 10:40:27 PM »
What can I say other than your Usual Spectacular scratch building!
RAGIII
"A man has to know his limitations": Harry Callahan

"Don't slop it on" Lynda Geisler

Offline IanB

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Re: 1/72 Hansa Brandenburg W 13
« Reply #18 on: September 17, 2019, 12:17:36 AM »
Lovely work as usual Stephen. In cases like this miliput UA your friend!

Ian