How do I cut 0.3mm copper sheet for hull plating tiles?

[Bob Cleek]

3 hours ago, Keithbrad80 said:

9 hours ago, Bob Cleek said:

First off, the "ponce wheel effect" produces convex "dimples," while the picture shows concave dimples. Big difference.

I think you have it backwards, the pounce wheel presses into the copper tape, creating concave dimples, flip the tape over and use the pounce wheel to create convex dimples that would better simulate rivets.

Yes, the ponce wheel creates "dents" that look like "bumps" when you turn the copper sheet over and put it on the hull. These may indeed simulate rivets, more or less accurately, depending upon the scale. The problem, however, is that no copper hull sheathing was ever riveted to a hull. Not once. Not ever. Fastenings were copper tacks.

 

When metal hulls came to be riveted together, a round-headed rivet was actually disfavored below the waterline in top quality construction. Countersunk headed rivets were used below the waterline create an smoother bottom.

Edited May 30, 2021 by Bob Cleek

[Bob Cleek]

3 hours ago, allanyed said:

Maybe at these scales it is better to have no nail pattern at all.     

 

Ya think?  

 

In a book somewhere (like everything else I can't remember) and perhaps in the USN ship model mill-specs, there is a rule to follow for scale detail. It goes something like, "At 1:48 scale, all detail larger in size than a foot in any direction must be represented." (And conversely, all detail smaller than a foot in any direction may be omitted.) So at what scale would a quarter or three-eighth's inch copper tack head not required to be represented?  

[Roger Pellett]

Round head rivets were not used in the hull above the waterline either.  Hull structure including shell plating was fabricated with Pan Head rivets.  The Pan Head was trapezoidal in cross section.  The rivet was inserted from the inside of the hull so the pan head fayed against the inside hull structure and was backed up by a heavy backing tool.  The plain end of the rivet called the Point was then hammered from the outside of the hull.  Since the rivet was hot it was malleable and flowed into the hole which had a slight taper.  When the rivet cooled it shrank pulling the joint tightly together.  A properly driven rivet would have had a slight crown 1/8 in or so high on the outside of the hull. See photos.  The last photo is of the William A. Irvin an all riveted ship built in the late 1930’s.  Even this close up the rivets are almost invisible.

 

The rivet beloved by model railroad rivet counters with the prominent domed shape was called a Snap Rivet.  The dome was formed by a special die.  Snap rivets were used to join light gage superstructure not highly stressed hull structure.

 

 

Edited May 30, 2021 by Roger Pellett

[Snug Harbor Johnny]

9 hours ago, druxey said:

If you absolutely want to pounce at scale, use watch gears.

 

  What a great idea, all one needs is an old non-working watch not worth repairing with a gear having the desired tooth spacing.

[Gregory]

11 hours ago, druxey said:

If you absolutely want to pounce at scale, use watch gears.

Like these:  

 

Watch Old Parts Gears Wheels

 

[Gregory]

10 hours ago, Bob Cleek said:

The problem, however, is that no copper hull sheathing was ever riveted to a hull. Not once. Not ever. Fastenings were copper tacks.

Interesting how this keeps getting lost or ignored in the discussion..

[Snug Harbor Johnny]

16 hours ago, Bob Cleek said:

You'd go crazy laying "wood tiles" to mimic copper sheathing.  It would be far easier to paste paper tiles and then saturate them in shellac. (Layers of muslin cloth soaked in shellac were laminated into sheets to make insulated circuit board material in the days before plastics. Shellac lasts forever and is very thin, so it won't obscure details.) Then paint and weather that surface. another approach that would work well would be to plank up the hull in the ordinary way and then give the bottom a light coating of gesso and sand that fair. Then scribe the fine lines in the gesso depicting the plating joints with a flexible straight edge and fine knife blade or scribe point (But don't overdo it. It's just the suggestion of a line that you want.) Then paint and weather.

 

  You're right about going crazy with wood 'tiles'.  As another reminded me, devildog's Thermie build (Mantua 1:124) used them - I was hoping to see more of that build, but there were no posts beyond page 3.  I saw another post of a Mamoli Victory build where the builder used the green stained wood provided ... and it did look like a lot of trouble.  Your paper idea would flex and glue to a faired surface FAR easier than wood - and the shellac (I'm a big shellac fan, and I've even compounded my own from dried flakes and ethanol - which works better and smells better than methanol as long as the ethanol is lab grade.  'Everclear' 190 proof still has 5% water which clouds the shellac.)  Paper does not have the grain that wood possesses, so only one  light coats of shellac might be needed.

 

   The watch gear idea proposed by another contributor might then (very lightly) make the slightest line of marks into the shellacked paper at the appropriate scale.  Then paint a thin brown coat and apply verdigris washes and it should look fine.  What I'll do is to make a 'test board' to see is this latest approach will work ... although it will be some time before I try and build a ship needing a copper sheathed appearance.    Johnny

[Bob Cleek]

  

 

  14 hours ago, Bob Cleek said:

The problem, however, is that no copper hull sheathing was ever riveted to a hull. Not once. Not ever. Fastenings were copper tacks.

 

 4 hours ago, Gregory said:

Interesting how this keeps getting lost or ignored in the discussion..

 

It is, isn't it? I sure don't get it. Shiny copper foil full of hugely out-of-scale "pimples" that don't remotely represent a prototype certainly doesn't make any sense to me at all. I suppose it's the "monkey see, monkey do" phenomenon. That and the fact that it appears a substantial segment of the kit builders have never been aboard a ship in real life, let alone a two-hundred year old one.  I guess they come by it honestly. If they're having fun, I suppose it's a good thing anyway,  

Edited May 30, 2021 by Bob Cleek

[Stevinne]

11 minutes ago, Bob Cleek said:

 

In response to:  

 

  14 hours ago, Bob Cleek said:

The problem, however, is that no copper hull sheathing was ever riveted to a hull. Not once. Not ever. Fastenings were copper tacks.

 

It is, isn't it? I sure don't get it. Shiny copper foil full of hugely out-of-scale "pimples" that don't remotely represent a prototype certainly doesn't make any sense to me at all. I suppose it's the "monkey see, monkey do" phenomenon. That and the fact that it appears a substantial segment of the kit builders really have no real-life experience with ships and the sea.  Imagine trying to build a model kit of a car when you'd only seen old pictures of them and the kit contained wooden tires. I guess they come by it honestly. If they're having fun, that's a good thing, I suppose.  

https://modelexpo-online.com/assets/images/documents/MS2260-SYREN-Addendum-CopperJig.pdf

[Bob Cleek]

5 hours ago, Snug Harbor Johnny said:

The watch gear idea proposed by another contributor might then (very lightly) make the slightest line of marks into the shellacked paper at the appropriate scale.  Then paint a thin brown coat and apply verdigris washes and it should look fine.  What I'll do is to make a 'test board' to see is this latest approach will work ... although it will be some time before I try and build a ship needing a copper sheathed appearance.  

The catch is "at the appropriate scale," and this is true not only for tacks in copper plating, but for any detail on a model.  

 

A coppering tack head is between a quarter and three-eighths of an inch in diameter. At 1:48 scale, that .25" tack head is going to be .0052", less than the thickness of a thick human hair and at 1:96 scale, it will be .0026" or half the thickness of a human hair. (Good luck finding a watch gear for your shop made ponce wheel that will replicate that!)  At 1:48 scale, a one inch trunnel is going to be .02", which is the diameter of a #76 twist drill bit and at !:98 scale, a #87 twist drill bit .  (Remember also that trunnels were not generally made of wood of color which highly contrasted with the wood into which they were placed.) If you can work to these tolerances, by all means, go for it, but realize that even if your work is done well, very few viewers will notice it unless they are examining your model under a magnifying glass. 

 

At most common model scales, copper tacks and copper plate laps are virtually invisible at "scale viewing distance." The fetish with out-of-scale "rivets" and trunnels is the result of a lack of understanding of the importance of scale viewing distance. Scale viewing distance is the distance a person would have to stand from the prototype to equal the distance from which they are viewing the model. Another way of looking at it, so to speak, is that if you are looking at a model with your eyes two feet from a model built to 1:48 scale, the scale viewing distance is 96 feet, so you have to ask ask yourself, if you are standing on the 32 yard line of a football field, can you see a quarter inch bolt head on the goal posts closest to you? And if your model is built to 1:96 scale, you'd be standing on the other side's 14 yard line trying to see a quarter inch bolt head on the goal posts farthest from you. 

Edited May 30, 2021 by Bob Cleek

[ERS Rich]

Amongst all this scuttlebutt.....only 1 picture of a recently built model....expressing an idea is not the same as successful execution.....

[Bob Cleek]

8 hours ago, Stevinne said:

https://modelexpo-online.com/assets/images/documents/MS2260-SYREN-Addendum-CopperJig.pdf

The MS Syren kit model is in 1:64 scale. Forgetting for the moment that coppering tacks are driven flush with the plate surface and don't "stick up" at all, the tack heads on her copper plating would be, at most, around 3/8" in diameter, but let's be generous in the spirit of artistic license and call them 1/2" in diameter. To scale, then, they would have to be .0078", and again, let's be generous and call that .008" scale size.  So, the "tiny tacks" with their points cut off that Chuck recommends for dimpling the copper sheets will have to be about the diameter of a #92 twist drill bit, which is actually .0079" and, properly, produce an impression that does not rise above the surface of the plate, which itself renders the "dimpling" exercise pointless. (Pun intended.  )

 

Applying the "scale viewing analysis" I described above to this Syren kit, the question to be answered if one were viewing this model from a distance of two feet, "If you are standing on the 43 yard line of a football field, what would a dime on the nearest goalpost painted the same color as that goalpost, look like?" For the sake of simplicity, we'll ignore variables such as the visual acuity of the viewer and atmospheric distortions.  

 

Of course, one needs to also make sure the scale thickness of the prototype's plates, which were probably around a quarter of an inch thick, are to scale as well, about .004", the average thickness of a human hair, so while you are at the football field, be sure to hang from the goal post a couple of pieces of overlaped quarter-inch plywood painted the same color and check out what that overlapping seam looks like from 43 yards away, too.  

 

 

 

 

 

Edited May 31, 2021 by Bob Cleek

[Snug Harbor Johnny]

34 minutes ago, Bob Cleek said:

The catch is "at the appropriate scale," and this is true not only for tacks in copper plating, but for any detail on a model.  

 

A coppering tack head is between a quarter and three-eighths of an inch in diameter. At 1:48 scale, that .25" tack head is going to be .0052", less than the thickness of a thick human hair and at 1:96 scale, it will be .0026" or half the thickness of a human hair. (Good luck finding a watch gear for your shop made ponce wheel that will replicate that!)  At 1:48 scale, a one inch trunnel is going to be .02", which is the diameter of a #76 twist drill bit and at !:98 scale, a #87 twist drill bit .  (Remember also that trunnels were not generally made of wood of color which highly contrasted with the wood into which they were placed.) If you can work to these tolerances, by all means, go for it, but realize that even if your work is done well, very few viewers will notice it unless they are examining your model under a magnifying glass. 

 

At most common model scales, copper tacks and copper plate laps are virtually invisible at "scale viewing distance." The fetish with out-of-scale "rivets" and trunnels is the result of a lack of understanding of the importance of scale viewing distance. Scale viewing distance is the distance a person would have to stand from the prototype to equal the distance from which they are viewing the model. Another way of looking at it, so to speak, is that if you are looking at a model with your eyes two feet from a model built to 1:48 scale, the scale viewing distance is 96 feet, so you have to ask ask yourself, if you are standing on the 32 yard line of a football field, can you see a quarter inch bolt head on the goal posts closest to you? And if your model is build to 1:96 scale, you'd be standing on the 64 yard line trying to see a quarter inch bolt head on the goal posts closest to you. 

 

  You are indeed correct ... I never quite 'got my head around the math' of scale, and see now that fretting about infinitesimal marks on a hull below the waterline does not make for much fun in building - especially since the details ABOVE the water line are far more important (like rigging).  Yet in some applications, a few items (judiciously) not quite to scale can lend a lot to the overall effect of an intermediate level build.  For instance, if you peek at my (old Billings 1:100) Wasa build - I put in rows of round toothpicks where the bulkheads are (I was a teen then) as 'tree nails'.  They are larger than scale tree nails should be, but still the light tan ends of toothpicks go well with the natural color of the mahogany planking.  I'm rather happy with the look of it, even though ships so constructed have a lot more of them - and it seems the Wasa planks were nailed with iron rather than tree nailed.  My job with recent work has been to correct major defects in the early version of the kit (loads more is known from Wasa reconstruction) in order to nudge the project closer to the prototype - but one can only do so much, yet still end up with something attractive to display.

[Bob Cleek]

29 minutes ago, ERS Rich said:

Amongst all this scuttlebutt.....only 1 picture of a recently built model....expressing an idea is not the same as successful execution.....

But expressing ideas often enables one to avoid a lot of unsuccessful executions! 😉

Edited May 30, 2021 by Bob Cleek

[Bob Cleek]

19 minutes ago, Snug Harbor Johnny said:

Yet in some applications, a few items (judiciously) not quite to scale can lend a lot to the overall effect of an intermediate level build.

It is at that point where "craftsmanship" segues into "art." Subtle artistic techniques, especially restrained and skillful painting and weathering, can "suggest" features and details which are, in reality, not there. This is what I call "impressionistic modeling:" the art of creating a compelling impression of reality in miniature.