36 Introduction This article is a culmination of ongoing work that has been carried out on a modelling project as well as numerous discussions on the ...
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Scale Welding the application of accurate weld effects on 1/35th scale armoured vehicles By Lee Lloyd
Introduction
Basic Welding Techniques
Other weld types often referred to are lap welds, corner welds, edge welds etc but
This article is a culmination of
Virtually all types of welded joint are
basically these are just variations of the
ongoing work that has been
classified into two major types:
two weld types above. Note that in our work here we are not concerned with the
carried out on a modelling project
physical process of welding but only the
as well as numerous discussions
•Fillet Weld:
on the same subject at my model
triangular in cross section between two
visual product that remains once the
club. In this article I shall
sections that are not in the same plane.
welding process has been completed.
A Fillet weld is roughly
describe one technique that has been developed to replicate scale
In all cases of replicating weld seams
welding based upon real-life
some thought must be made prior to
methods and welding processes.
actual application and to what kind of
I shall describe the tools and
effect we are trying to achieve. This must
materials used for this work and
take into account the materials to be
then illustrate in practice both
welded, the circumstances under which
some simple and complex
work would have taken place and the skill
examples of scale welding. The
level of the welder. Whilst the latter three
article will be finished with a brief
points may seem a bit excessive to be
description of other methods,
•Butt Weld: A Butt weld is a weld between
concerned with, if you are trying to make
both scratch building and
two sections in the same plane.
your scale welds as accurate as possible
aftermarket products that can
they should be considered. With respect to
also be used to replicate these
materials and armoured vehicles we are
effects.
usually looking at either the welding of armour plates or on-vehicle accessories. The welding of armor plates is usually done under factory conditions with skilled
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personnel. This should mean that welded
The Tools to Be Used
Stage 1
joints are very uniform and neat; i.e. the welding of armour on German tanks
So how can we replicate such effects? We
especially in the early years of World War
need a set of tools. In our case our welding
2. This can be contrasted with the skill
torch will be a set of hand made brass
level of Russian welders of the same
formers, our weld beads will be milliput
period whose main tasks were not
and our section to be joined will be the
necessarily to do things perfectly but
plastic, brass sections etc of our kits. The shaded portion of the tube above
instead to complete them fast. If you look at welds on Russian vehicles of this period
In order to make a tool that can simulate
needs to be removed. This can be carried
we can see on average that the weld
the look of a weld bead we have to identify
out with a standard flat face needle file but
quality on AFV’s was of a very mixed
exactly what such beads look like. If we
care needs to be taken especially when
quality. As the project work to be carried
look at the diagram below we can see how
dealing with the very thin diameter tube
out here is on such a Russian vehicle of
a weld is formed. It should have the look of
sections. The end result should look as
this time period we will attempt to show
a number of evenly spaced ridges that
below:
weld effects of both good and poor quality.
have a half moon shape and that run a distance with constant width.
Some examples of weld joints that can be easily replicated and are relevant to all types of vehicles of all time frames can be Stage 2
illustrated below:
•Fillet Welds Round off the edges of the semicircular mitre
multiple
edge of the tube by removing the shaded blue portions above, this should result in the tool shape below:
convex
convex
convex
Stage 3
concave
Depending upon the thickness of the tube being modified you should chamfer the tool edge to ensure that the weld edge is
•Butt Welds
as sharp as possible. This is illustrated The tools to be used to create such effect
below:
should therefore be capable of creating a half moon shape when applied to our welding material. To create such tools we need to use a number of brass tubular square
sections, in our case K&S brass tube was
chamfer this edge
used in a number of small diameters. It is best to make a number of such tools from as many varied diameters of tubing that can be obtained in order to make welds of different widths. single vee with backing bar
To create the tool we need to perform the following steps:
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For the weld seam itself I always use
is at all times to keep your fingers, milliput
superfine white milliput. I have tried other
and work surfaces wet! In this image the
materials, most recently Revell Plasto
weld is currently about half the final
putty, but in most cases I have found the
diameter that we require.
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cohesive consistency of such materials in small quantities to be very poor. When
Pic 2 shows the templates that we will use
using Milliput you can roll this material to
for our weld examples, basically they are
very thin diameters provided you keep the
squares of styrene covered with a grey
material wet. I mix my Milliput and roll it on
primer in order to make a good
a wooden table top in a pool of water and
photographic colour contrast. To lay the
with a bit of care and attention can roll out
weld we wet with a paintbrush the corner
>1mm diameter lengths of putty. I have
groove that we are to use and then lay the
found once you have created a desired
milliput roll into that same space.
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putty diameter you have a relatively short working time as in such small quantities
Now that we have the weld roll in place we
the Milliput tends to dry out quite quickly.
must cover the area in water. This will serve to blend the edges of the milliput to
Once you have your Milliput welds lengths
the sectional surfaces as well as providing
it is a simple matter to ‘drape’ them
a medium that will prevent the weld tool
around/on the unit to be welded. Make
from sticking to the milliput. Let the milliput
sure when you do this you keep you
harden for a few minutes so that a surface
applicator (fingers?) wet as in such small
skin forms before applying another small
quantities the Milliput has a fantastic ability
amount of water.
to stick to anything other than what you
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want it too! For the sections to be welded
In Pic 4 we can see the weld tool in a pin-
a certain amount of preparation is also
vice before application to the milliput
necessary. When making a fillet weld there
surface. To create a convex weld we use
should really be no modifications made to
the OPEN end of the groove in the tool,
the sections as the putty can be applied
facing the weld, and then sharply jab the
directly at the desired location. If a butt
tool repeatedly, but not deeply, into the
weld is to be made it is best to score the
surface of the milliput. What we are trying
surface as per the weld example pictures
to achieve is a ridged effect that is semi-
so that the weld can be built up properly
circular in shape but that does not
and does not stand too proud of the
penetrate completely the milliput. Always
sectional surfaces when finished. A good
draw the tool down the weld, i.e. as in the
tool for creating such scribed lines is a
direction of the arrow as shown as this will
panel scriber. This tool has a reverse cut
create the correct overlapping nature of
blade that creates cut lines that leaves no
the weld. It is VERY important to keep the
burs in a plastic surface. By creating a
end of the tool wet when welding
groove into which the putty can be set you
otherwise the milliput WILL lift from the
are guaranteed to keep the putty in place
surface.
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while making your weld seam. In Pic 5 we can see the finished weld
Basic Welding Simulation
before a final blending of the edges with water and a paintbrush into the sectional
Now that we know how to make our weld
surfaces again (application of the weld tool
seams let us put the practice into theory.
will always tend to move the milliput
In this section we shall make some simple
around regardless of how careful you are).
welds.
In this image you can see how certain areas are tidy, others are rough and
Example 1: 90° fillet weld (convex)
downright messy, but overall we have an accurate 3-dimensional fillet weld. The look
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This is the simplest type of weld to make.
of the finished weld is purely up to how you
In pic 1 we can see the rolling out of
want you work to look again depending on
milliput to very fine diameters – the secret
the time frame and type of vehicle/weld.
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7
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9
10
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pic 11 (Note there is still some edge clean
Example 2: 90° fillet weld (concave)
Example 3: 90° butt weld
In our next example we shall perform the
In the last of the simple weld examples we
same process as described above but this
will cover a butt weld. In this case the
time we shall replicate a concave weld.
template to be used is two sections of
The same process for creating a roll of
styrene with a small gap left between
milliput and priming the sectional surfaces
them, backed by another styrene strip.
In this section we will look at some
with water is as previously.
Here we are trying to replicate the gap
examples of more complex welding
between sectional surfaces that would
effects. We shall only cover two examples
Instead of blending the edges of the
naturally exist or that has been replicated
here but the range of effects to be
milliput into the adjoining areas, we force
on a kit using a panel line scriber. This
achieved is only dependant upon what the
the milliput into the corner surfaces as
template can be seen in pic 8.
effect is that you are trying to replicate.
here by the use of the end of a paintbrush.
In pic 9 we can see the milliput roll has
Example 1: 90° multiple fillet weld
Once we have the milliput in the shape we
been pressed into our gap between our
desire we must once again wet the surface
weld sections. Don’t worry if part of the
A multiple fillet weld is a join that has
and leave to allow a skin to form.
milliput is squeezed out over the edges as
overlapping weld seams that are designed
To create the weld seam in this case we
this is an effect that we want. Again make
to give a greater strength between the join
must use the CURVED back edge of the
sure the surface has been layered with
of sectional surfaces. The effect that we
weld tool. This is used in exactly the same
water and the surface left to harden.
are trying to replicate here can be seen in
up to be carried out here).
Complex Welding Simulation
smoothly as possible. This we have done
manner as in the previous weld but in this
our examples as described in the section
case we will leave our ridges in a concave
To create our weld we use our tool as
on Basic Welding Techniques. In our case
shape. This is illustrated in pic 7 before the
before using the OPEN end of the tool. This
though we will cheat slightly as we do not
final blend of the edges into the
time we press down through the milliput so
need to create an entire series of
surrounding sections has been carried out.
that all excess material is squeezed out to
overlapping welds.
The image does not show too clearly the
the sides. What this should leave is a weld
concave nature of the final shape of the
that is at the level of the sections that is
In Pic 12 we have taken our fillet sections
weld but rest assured this is the exact
being welded and can be seen in pic 10.
and have added a small strip of triangular
shape you get. This can be compared to
Scrape away the excess material and
styrene directly into the grooved area. This
similar welds on vehicles and once painted
again with some water and a paintbrush,
is done to save us time and effort in having
and washed/weathered will blend in very
gently blend in the edges of the weld to
to build the depth up using milliput. Note
well with the surrounding detail.
the sectional sides. This should leave a
that in this example we are creating a big
weld that has an appearance to that as in
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scenarios you will probably only need
consistency from the others; essentially we
decided to mix in some of the coarse
overlapping rolls of milliput with no depth
will try to create a splatter kind of weld
grained CAST’a’COAT into a roll of milliput
filler to create the desired effect.
effect.
before application to the weld area. This
As before the same procedures apply with
In the same manner as before we have a
respect to layering of water on the
butt weld template to which we have
Once this was mixed in, and by this I mean
surfaces to be worked. In Pic 13 we can
already applied a single weld bead
the CAST’a’COAT was rolled into the
see the first layer of weld has been applied
(convex), using the methods as described
surface, rolled back into a ball, rolled out
along with the surface effects being
previously, see Pic 15. In this example you
again and into more CAST’a’COAT until I
finished. Blending of the weld to the
can see a small run of milliput to the left of
had a nice consistency of material
sections is not done at this stage.
this seam. This is a small roll of milliput I
throughout the volume of the milliput and
added as a base filler as I had made the
not just stuck to the surface.
can be seen in Pic 17.
In Pic 14 we can see the application of a
butt weld sections a bit too far apart! The weld was then applied to the sectional
second weld seam. All that needs to be done now is to blend the edges together
In Pic 16 we have added the second weld
surfaces but this time was detailed with a
using water and paintbrush again. Try not
seam. These have layered nicely together
toothpick as I did not want to create a
to blend in too much the division between
but as before no final blending is done until
ridged effect here. The toothpick was
the welds where they touch so that you
the final weld is added as we do not want
gently pressed into the weld surface and a
keep a fine line of demarcation. This photo
to apply too much water which could have
certain amount of material was picked out
again does not show the volumetric shape
the effect of dissolving too much milliput
to the sides in order to simulate a very
that is obtained by this method due to the
and thus ruining the fine detail on the weld
messy process indeed. The end result prior
angle at which the template has been held
ridges.
to water blending can be seen Pic 18. The final result looks very rough but even at
up to the camera but the general nature of
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the finished product can be visualised by
The next stage is to create a weld seam
this stage the splatter weld has a very
again considering the shape of the depth
that has a much rougher surface
rough feel to it surface that with correct
area in Pic 13.
consistency. In order to make this I have
painting/washing etc will dramatically bring
used a product called CAST’a’COAT. This is
out the detail.
Example 2: multiple butt welds
a product that consists of sets of granular
In this example we shall go one step
materials in two grades. The idea behind
A good example of the effect I was trying
further and attempt to create a more
this product it to replicate the rough
to achieve here can be seen above We
complex example of welding. In this case
surface effects on a variety of materials
can see very clearly the triple weld with
we will create a triple butt weld where one
and surfaces.
different consistency
weld section has a very different
In order to create a ‘splatter’ type weld I
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described above. However in my never ending search for accuracy in my work and in the interests of realism I have not found these methods generate the effects that I desire.
Aftermarket Goods Two products that exist as aftermarket products are from ABER and Archer Transfers. From ABER you get a very fine fret that has a number of weld seams that can be used for various effects. I have seen these and do not really care for them as the patterning on them is too regular and repeated and the runs tend to be of too constant a width.
Other Methods for Scale Welding
the material never resolves to the correct
With respect to the Archer Transfers (at the
surface plasticity as is required to work
time of writing I am not sure if these
This article has covered one method for
with. You either find that the weld is still too
products are still actually available) these
accurately replicating weld seams on scale
rigid to surface detail or in fact becomes
are designed to work by creating a slightly
military vehicles. Of course this is not the
too soft and will hold no detail. I have tried
raised surface once applied so that when
only means to do this and other methods
this method using the weld tools I have
painting & weathering they can be made to
exist in common practice that includes
created but could not correctly replicate
stand out. Again I have seen but never
both aftermarket products and other
the ridged effect of a weld.
used this product but as above I have found the runs to be too regular in shape.
scratch-building processes. 2) Pyrogravure. The use of what is really a
Also their very nature as transfers does not
Other scratch-built methods
low-temperature soldering iron is another
give them enough of a raised 3D shape
1) Perhaps the most common alternative
method for creating weld seams. In this
that is often required when replicating such
method for replicating weld seams is to
case the pyrogravure is actually applied to
effects.
use the stretched-sprue/styrene approach.
the surface of the kit (which may also be
In this method a circular section of styrene
previously applied stretched sprue) and is
A product which we have discussed at the
or plastic is heated or bent to fit the shape
used to ‘melt’ tiny areas to get the desired
Tyneside IPMS model club that would be of
of where a weld seam is to be made. An
effect.
use would be weld seams that are similar to ATAK/Cavalier zimmerit sheets. Very thin
application of liquid styrene glue is applied to the parts to be welded with an amount
I have never tried this method but have
sheets of resin could be created with a
of his glue being applied directly all over
seen some very nice but also very bad
wide variety of weld effects to replicate
the surface of the weld bead. Once this
results from using this tool. What you have
much of what we have covered here. It
glue has significantly melted/softened the
to remember is that in modifying the actual
would be nice to see a manufacturer
weld this part can be detailed by using
surface of the kit you are changing the
introduce such a product.
knife blades, toothpicks etc.
surface volumes into shapes that are not meant to exist – i.e. the melted material is
Conclusions
While this method does work I have found
not removed but is pushed to one side.
Hopefully I have shown here an effective,
that it is very difficult indeed to get an
This can result in raised areas that do not
highly accurate and cheap method for
accurate pattern to form on the weld as
replicate real volumes being modelled.
replicating all types of scale weld process
Also as the tip of a pyrogravure tends to be
seen on military vehicles. The method is
round (I am sure a tip the shape of a tool
simple and relies only on common tools
described here could be fabricated) when
that are available to all modellers and in
welding you will not achieve a ridged effect
fact is quite a quick process to replicate
in your work.
one you have carried it out a few times.
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In summary as I have said I have seen some very good results produced when using both of the methods I have
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