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To scribe or not to scribe.....
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TOPIC: To scribe or not to scribe.....

To scribe or not to scribe..... 8 months, 2 weeks ago #2669

  • jugjunkie
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I was going to do a bit of a tutorial at our last meeting but the chairman did not allow it. He said there is no scribing on tanks so nobody would be interested. So I have decided to do that tutorial here because at least I don't need to ask for permission!

I am a huge anti-fan of raised panel lines. I know in the old days there were no real options for manufacturers and we all built them and they still made great kits - they still do and some of those Testors and Monogram kits with raised panel lines are still either the only game in town, or at least the only decent game in town. Some time back I wanted to build a 1/48 Thud so badly that I was prepared to tackle Monogram's awesome kit (Trumpy weren't around yet). I started scribing that beast and after about two weeks the top two wings sections were done (with quite a few deviations to Republics specifications and some panel lines that were more than questionable), it got boxed and has not seen the light of day since – but things change!
Up until then I had one or two jewellers screw drivers, metal rods, and a myriad of other sharpened objects that I had fashioned into a sharp edge, trying to find that elusive “perfect tool” - enter Bare Metal Foil Company! I saw this tool while browsing their website one day looking for decal paper and foil. The write up was impressive and I decided to order myself one (ordering from over-seas was still a major issue and payment was a flippen nightmare). After my first attempt at using the tool, I was sold. It made the job so much easier because of the shape of the business end. As described by BMF Co, it is a hollow V which allows a sliver of plastic to be completely removed in a V shape. The sides of the cut are relatively clean and bur free and the cut is sharp and just deep enough. However it did take me awhile to perfect its use because like any tool, it does require some technique to get the best out of it. My recommendation to anyone wanting to do re-scribing, is this is the bare minimum requirement to even attempt the job. www.bare-metal.com/Introduction-To-Using-Bare-Metal-Foil.html
Anyway as I said before with new manufacturers springing up every other day and with new kits getting released almost on a monthly basis, I don’t think the need to re-scribe an older kit will really be necessary soon – but there are still exceptions even today and because of our insane desire to get perfection, there is always going to be a need to become proficient in this task to improve on manufacturers offerings.
So I recently picked up an Academy 1/48 U2 (old Testors kit) and due to circumstances of late with my move and all, it was the only kit I had on hand so I decided to start with it in order to maintain my sanity and as a bit of relaxation away from painting walls and ceilings, fitting bathroom taps, cleaning blocked drains and gutters, etc, etc, etc.
The kit is very nice with not too many parts and looks like it could build into a nice model – but it has raised panel lines YUKKKKK!!!!! So the first job now is too remove the raised detail.



Most people will just grab the 200 grit sand paper and attack the plastic until all traces of the offending lines are laying on the desk – a dusty mess. I don’t do that. It’s difficult to really tell you why but I hate mess so a big part of the reason is I don’t like the messy sanding route. Also I find sanding is too indiscriminate, it’s too easy to damage or even lose some detail that you really don’t want to lose or try and repair. I am going to do this tutorial in a very much step by step manner because I think it’s important for readers to fully understand how and why I do things Myyyyyyyyyy Wayyyyyyyy (apologies frank)

PART 1 – FLAT SURFACES
STEP 1. Reference. As with all new projects my first Port -O’- call is the referencing. In particular in this case, I try and find those schematics that show all the panel lines as in this case.



Armed with this, the kit itself and perhaps a few good pics we whistle a tune and start on our merry way.
STEP 2. Removing the raised detail. At this point now I have a good look at the kit’s parts break down and start to plan how, when and what. The first practical job is to remove all raised detail but just before I dive in with the nitty gritty let me elaborate on the how, when and what. Scribing is difficult for a number of reasons. Most of the problems around scribing are concentrated in the SHAPE of plastic. This poses two problems:
a) it sometimes makes the holding and working on a piece very difficult
b) and it makes the actual scribing of lines in a very specific direction almost impossible due to fact that you are dealing with complex curves and straight lines almost all the time.
An added difficulty is that you have a number of different pieces that ultimately need to be put together and match up! So at this point you need to decide what parts can be worked on independently, and which parts need to be mated before you work on them. My rule of thumb is very simple – wings, vertical and horizontal stabilizers, gear doors and all other FLAT or free moving surfaces can be done independently, fuselage, intakes and other major sections – only after construction.
Let me try and explain. Wings for example are completely independent (usually) of the fuselage in that they do not share panels with the fuselage. OK modern jets do but because we are looking at flat surfaces, I would still treat the wings as separate entities because once the wings are attached to the fuselage, it would be good to use the wing panel lines as reference for the fuselage lines. Also The top and bottom sections of wings mate along the very fine leading and trailing edges only so mismatched lines can easily be hidden (most times anyway) In the case of say a WWII bomber where the leading edge is very prominent then a bit of pre fitting and marking may be needed.
So each wing surface (top and bottom) would be completely scribed first, same applies to all the other control surfaces, gear doors, etc, and the fuselage gets re-scribed after it is mated (both sides attached). The reason for this is that in most cases the kit manufacturers can’t even match up the panel lines on the two fuselage halves so if we are going to use the existing panel marks as a guide and they are off, then so will all that hard work be off. Another reason, believe it or not is that it is easier to use the curved templates on a fully rounded surface than on a half round surface but you will see where I’m coming from on that later.
So starting on the top wing, first thing I notice is a panel with some raised detail that I want to keep…..



So the first step is to cleanly remove as much of the raised detail as possible and for this task I have a lovely fat paddle like blade, don’t ask me for the number, I don’t know. I use this to basically lift the panel line off the plastic.



Again let me digress just a little to elaborate on a very important issue which is tools. Besides my trusty BMF scriber it is almost imperative to get yourself a collection of metal shape templates. These are indispensable and do not even try and tackle any scribing job without them. My paddle blade is also a tool that you will have to fashion, buy or steal but you must get one as you will see later on.



So positioning the blade at a very shallow angle to the ridge of the panel line, with just a little down pressure to keep the blade edge against the plastic, move your blade in the direction of the ridge and check that you get a good “Nigger hair” shaving which confirms you are lifting the ridge. Call it what you want, ball hair, nigger hair, shaving, whatever just be sure it’s there. Don’t be shy to go back again if needs be but IMPORTANT!!!!!!!!!! DO NOT LET THE BLADE DIG IN. This will cause all kinds of kak later. Also do not get over enthusiastic with the shaving. You only want a nigger hair – not a slice of scalp! Jokes aside be a bit careful with this because it is imperative that you a) do not damage the plastic and b) you want to have some indication of where the original line was.



Once I have removed most evidence of the raised detail, I go around with my finger and just check that there are no points overlooked.



Next I take about 600 or 800 grit finishing paper and gently scour the whole surface making sure not to damage any raised detail that must be retained.





And the final step in removing the raised detail is to take an even finer grit finishing paper, about 1000 to 1200 grit and again go over the whole surface, just smoothing everything out. At this stage you must not be able to feel any unwanted surface detail ….BUT do not remove ALL traces of the original line because unless you want to start using a Vernier spending hours to find your way around, then be sure you have some feint indication marks to put the lines back where they should be. This is especially relevant on long curved panel lines, jagged lines or lines that don’t follow a predictable arc.



STEP 3. SCRIBE NEW LINES. Now the fun starts. The first thing you need to do is position the piece and get comfortable. That may sound a bit stupid but I have very good reason for saying this. For me, pulling the tool towards myself or pulling from left to right, gives me good control and I can control pressure and direction much better than trying to push the tool away from myself or trying to work from right to left. I am right handed so the first thing I do is decide which lines to add first and then position the piece on the desk and fix it down with tape so that it is stable and comfortable to work on. I may move it around quite a few times in the course of a full re-scribe.



Again let me introduce a tool I find indispensable, my line tool! This is a thin, flexible but sturdy piece of Stainless Steel I got – God knows where and when. I find it has just enough bend to get around the profile of most wings but also has the weight and thickness which allows me to hold it firmly without having to tape it down for each and every line as is the case with the really thin shape template steel as you will see later.



So here you can see I use the feint original lines as markers and by pressing down firmly on the ruler, and gently scour a line making sure I see the tell-tale nigger hair spiral again telling me I have the right pressure and depth. If you did not read the BMF article I pointed you to earlier in the article, then go there now and read about the angle of the tool, etc, you get to know what’s right after a while. DO NOT move your scriber back and forward, this is not necessary and it will damage your line. The scribe is not designed to be used in reverse so you will cock it up! All you need to do is hold the tool at 90 Degrees to the plastic surface and with finger pressure only, drag the tool against the ruler in the direction of the line, if you see the fine nigger hair, you have a good enough furrow. If you are worried about slip on the ruler, you may want to keep a piece of tape on one end as an anchor while only holding the opposite end steady.



So now I have a nice new panel line but no matter what you use to scribe a line in plastic, you will have the trench effect – a furrow with two raised sides or burs. A good tool just limits the height of these burs but they are still there. If you run your finger over the new line you will feel these burs. It is good that they are there because you can use them as an indication that you have penetrated deep enough over the complete length of the line. On some longer lines, you may have let up a bit on pressure at some point due to weight shifting and this could result in staggered lines which may only show up once you start with your panel wash. Out comes the trusty paddle blade again and exactly as you removed the original raised panel detail, you remove the burrs but you need to be a bit more careful now not to “dig” the blade in and damage the line or plastic surface because unlike previously, you will not be sanding again. To check your work, run your finger over and across your line and it should feel as smooth as before you started scribing.



JOB DONE!



That covered the easy flat surfaces but what about the complex curves and shapes? Well everything is done exactly the same but the method differs a bit. On complex curved surfaces you don’t have the luxury of being able to tape your work piece down and have that comforting stability. With these parts you are going to have to have hands on most of the time because the scribe will not be able to stay on the same plane through-out the completion of the line which may be 360 degrees around the fuselage. So here tape is essential. One line around a fuselage may require up to 4 different cuts!
In Part two of this tutorial I will cover the issue of scribing on complex curves (need to get there on the U2 first)
The following user(s) said Thank You: Dudley, yarib

Re: To scribe or not to scribe..... 8 months, 1 week ago #2670

  • Esquad
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Wow an awsome tutorial JugJunkie, thank you for all of the effort
International man of mystery...I'm a Jetsetter....Jetsetter!

Re: To scribe or not to scribe..... 7 months, 1 week ago #2677

  • Eric
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S%@#*! Now where did that piece go??!!
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