Hello Friends!
I get a lot of emails and questions.
My name is Egor, absolutely all the models that you see on the site, I glued
myself.
This is more than 150 models of aerotetris in 25 years.
That's how many years I've been inventing and building CNC machines, drawing 3d,
cutting styrofoam, gluing models.
I have skills and knowledge that I want to share with you.
Please ask questions, I will try to answer them.
My task is to describe all aspects of working with the AeroTetris kit.
Keep an eye on the update.
Reposts are welcome.
Three reposts and you have an additional 3% discount (this discount is combined
with others)
The material used for the production of aerotetries is a building insulation -
extruded polystyrene XPS.
Another name for extruded polystyrene XPS (eXtruded PoliStyrene) is extrusion.
The price range of this material varies widely, it is required for different
construction tasks.
Over the years of working with this material, I have found several options that
have shown better results.
This is URSA XPS light styrofoam having a
density of 25-30 kg/m3.
Also, recently, I started using light green ThermoGreen styrofoam,
you could see it in the implementation of the F14 Tomcat-2700 model.
This is the best solution for our modeling tasks.
Unfortunately, the manufacturer of this material is guided by its tasks.
The
error in construction is quite large and therefore even this material, proven
over the years, is produced with errors.
If for the task of insulation, an error of 1-2-3mm is allowed for the thickness
of expanded polystyrene,
then for 3D modeling tasks, such an error is high.
The thickness of the styrofoam sheet is not uniform across the entire plane.
If we work with a thickness of 50mm, then in real life, we have a thickness of
49-51mm and
this affects the geometry of the model.
As a result, we have a slight discrepancy when joining parts,
when joining
layers, and as a result, a deviation from the central axis of the aircraft.
For a novice AeroTetris modeler, this can be critical.
Here I will try to tell
you how to solve this problem and get a perfect copy.
I am always surprised by the fear of numbering parts. I'm spending one evening
on this.
Just start putting in the part numbers and you'll see how fast and easy
it is.
- Always use a slipway (many use a laser level) to control the
straightness of the axes of the model.
- About the preparation of parts before gluing.
The front side of the styrofoam sheet is glossy. Accordingly, this surface has
weak adhesion when bonding.
It is enough to scratch this side of the part a little and the bonding force
will increase many times.
Those sides of the part that are cut off on a CNC machine do not require such
preparation and are glued securely.
- You've all seen the models on the site. The surfaces of each model are
almost perfect.
This is achieved by using pins to evenly and precisely position the parts and
layers relative to each other.
Please use pins in your work. This will save you a lot of time on finishing the
finished model.
Please note: all models on the site do not have mechanical treatments after the
glue has dried. It's just the parts and the glue.
AeroTetris is a lot of independent work and independent decisions.
Many modelers experiment and use different glue options. In vain. But maybe
you'll find a better glue option!
- Super Glue (cyacrinolate) - instant fixation and the inability to
position parts and layers of the model.
- Mounting foam is a complex adhesive for connecting parts and layers of
the model. An increase in the volume of the adhesive seam.
- Some modelers suggest using a paper painting chip. Lack of adhesion on
the surface of the part. Low adhesive force of the tape.
- One day, someone ordered a second, exactly the same model two weeks
later.
He used solvent-based glue and the parts just dissolved in this composition.
Acetone and solvents dissolve styrofoam (!)
- My recommendations are glue for wood and paper. It is called PVA or
White Glue.
This is polyvinyl acetate, a dispersion of polyvinyl acetate in water with a
plasticizer and special additives.
It comes in different types, but I'll tell you about two: ordinary and
moisture-resistant. In my experience, the simplest, plain,
White glue gives the best results. Moisture-resistant White Glue is
aggressive and rough when drying.
Mechanical processing is difficult.
When gluing parts with White glue, we have at least an hour to properly position
the parts and layers.
White glue forgives mistakes, unlike the above options.
- My recommendations are the alternate gluing of parts according to the
principle of a child's pyramid.
Exactly - the principle of the pyramid.
I know of several unsuccessful assemblies when the modeler glued the left and
right parts of the fuselage separately.
In this case, the discrepancy in the length of the mirror halves of the fuselage
can be 10-15mm (!)
And according to the pyramid principle, we have the opportunity to level these
errors.
There won't be a big gap in one node, and there won't be any gap at all in the
other.
In general, at a length of 2200-3700mm, the difference in the thickness of
styrofoam will not be noticeable.
Later I will tell you how I fill these gaps.
The first layer (usually 2 mirror parts), the second layer, the third layer, I
glue immediately and set aside so that the glue dries.
The first layer is the cone, the nose of the aircraft, I cannot load this
segment of the fuselage for gluing.
Therefore, the next segment is the gluing of 4-14 layers of the fuselage.
With so many (10*50mm) 500mm layers, it is convenient to work on the desktop.
This segment can already be loaded with 5-10 kg (I use plastic 5 liter water
bottles)
The entire fuselage is glued in sections of 10 layers.
After the glue dries, the alignment of the segment and fuselage along the entire
length is checked.
If there is a discrepancy, the segment is trimmed to preserve the axes of the
model.
When gluing parts and layers, you need to focus on the outer surface.
Irregularities, they are always there, it is better to place them inside the
fuselage, it is not so critical.
Don't spare the pins. Someone will be surprised, but for a 2800mm scale model, I
can use 1000 pieces.
It seems like a lot only at first glance.
They are easy to edit, stretch, bend, flatten, bend, lengthen and shrink
styrofoam parts.
Sometimes, after the glue dries, the pin can be difficult to get out of the foam
layer.
In this case, a medical forceps with a grip will help. I'm sure there is such a
tool in the modeler's workshop.
If the pin comes out with difficulty or tears out part of the material, turn the
pin with tweezers, it will easily come out of the foam.
I do not use reinforcement beams inside the fuselage, my task is to show
the showcase, the outside of the prototype.
But they will help you maintain the straightness of the fuselage and tail.
Always use power-ups.
Usually, on 2800 scale models, 12, 14 and 16 diameters are used.
On models from 4000mm (TU160-4500 and
SR71-4100), beams with a diameter of 20mm
are used.
You make your own decision to use wood, glass or graphite tubes. Fishing rod
parts are a good solution.
In the wings, almost always, there are two beams passing through the fuselage.
Do not give up on such a decision. This reinforces the whole structure of the
prototype.
And with the fuselage beams together, the reinforcement is more durable.
This is necessary if you are building a model for an impeller or a jet.
If you find a clear discrepancy between the parts during the gluing process, do
not rush.
There may be several reasons:
- the numbering of the parts is not correct. in this case, let's forget about
the part and continue gluing the parts and layers;
gluing the parts together, we will later find the right place for the "extra"
part.
- do not rush to throw away the scraps after numbering; sometimes I throw away
the necessary part, considering it a waste;
this happens rarely, but a large garbage bag will save you in this case; you
will always have time to throw away the styrofoam scraps.
- I draw your attention each kit has absolutely all the necessary parts for
assembling the model;
in my practice, there were two or three cases when 2-4 parts were missing from
the kit;
thanks to your emails, we made upgrades and today our showcase does not contain
errors.
but it remains a mystery to me :) how I managed to glue the model without the
necessary parts of the aircraft?
- if you have checked all of the above, glued the segments of the model and see
a clear discrepancy between the parts, cut off the excess;
it is quite possible that the thickness of the material in this place was
overestimated;
this can also happen if there is an excess of glue or a lack of cargo for
gluing.
I will devote a separate story to gluing wings and plumage.
For a number of reasons, I can't cut out a piece that looks like a knife blade.
Therefore, we increase all wingtips by 10-15 mm for subsequent trimming.
Then the edge of the wing turns out to be neat and correct.
Precautions: The kit contains small parts, you must not given the children
under the age of 3.
Important: DO NOT USE LIQUID NAILS !
Choose adhesive not containing the following chemical compounds: organic
solvents
(acetone, acetic acid ethyl ester, the solvent inksturpentine);
saturated hydrocarbons (alcohol)
and petroleum (gasoline, kerosene, resins,
etc.), since the cellular structure when expanded polystyrene contact
with the
above compounds may be damaged or completely dissolved.
Unacceptable use of sand
- cement mortars intended for this material in construction.
Set of layers of this model is made of styrofoam URSA XPS/ThermoGreen.
Make sure there are no medical contraindications, allergies (unlikely) this
material used for adhesives and so on.
You can use other, similar in its characteristics, materials from another
manufacturer without prior notice customer.
When using do not forget about safety.
Use disposable gloves. Pay attention to respiratory protection and vision.
The composition of adhesives may include toxic substances. Choose products
proven manufacturer .
The kit comes as is.
It assumes that you have learned enough threads on niche sites dedicated
assembly this and other models.
You understand and acknowledge the difficulties that arise when building the
model.
You assume all the consequences if not correctly assembled and then using this
model.
Refund from the manufacturer is not provided.
Each set is carefully checked before sending and packed in containers for
transporting/shipment.
Assembly models.
Model length - mm ( + -5mm )
Wingspan - mm ( + -5mm )
Aircraft according to the thickness and gloss removal thickness of the adhesive
seam.
Weight used Styrofoam and glue must not exceed 600 grams.
Recommended follow-weave model films, tape or fiberglass to impart rigidity and
strength model.
Do not forget that the weight
model at this grow, depending on the applied technologies stitched.
For proper assembly required:
- Moment Waterproof PVA glue. Super PVA D3
- Syringes or brush glue 8 -12mms
- Rags to remove adhesive residue, removing stains.
- Dressmaker pins - needle at one end of which is made of either plastic eyelets
or beads.
Need 200-300 pcs.
- Stationery knife.
- Waterproof sandpaper to remove the gloss on the fibers. For example, GermaFlex
P180X, 200h500mm size.
- Stitch Marking Wheel.
Recommend to make a set of shipments and stick them above pelt.
Enough segment size 500x500. The kit used wooden mandrel 200-250mm long,
diameter 10, 25, 50mm.
wooden bars 20x20, 40x40, 60x60, and flat metal spatula, a 20-40mm. Recommended
abrasive sponge.
Can be purchased at auto stores, auto-chemistry department.
Finishing produce finer sandpaper, grain selection at your discretion .
Also need a set of goods, used under gluing layers.
Allowed the use of acrylic ( NOT ALKYD !) coatings on wood.
Assembly model should start with the preparation of the workplace and the
necessary tools .
Make sure you have enough free time.
1. Arrange items in the order they appear .
2. Remove gloss polystyrene with all the details. Calculation model was made of
a layer thickness 49.4-49.6 mm.,
So do not overdo it. gloss shoot up to 0.2-0.3mm. on each side (enough to
scratch).
This is done for better adhesion layers when gluing.
3. Conditional section details on 4-5 sites and start gluing.
4. Fold the two adjacent layers. Note the error to be aligned with the gluing
pins.
Since heterogeneity
the material used, as well as the difference in mean lengths of projections of
the layer
thickness of the cut varies depending on the direction
of movement and velocity cutting the string.
This deviation from the rules is
not a marriage, AeroTetris continues to work on it.
5. Brush evenly over the entire surface gluing, apply glue to both edges of the
layers.
The consistency, the adhesive should not resemble a
thick sour cream. It should not spread over the surface.
If necessary, use an
approved solvent adhesive. In this case, for Super PVAD3 such a solvent is
water.
6. Connect the two parts together. Along the perimeter of the adhesive joint,
leveling the surface with your fingers,
tighten the pin so that the pin passes
through both layers angled.
After gluing, they are easily removed. The resulting item check on all sides,
including internal grooves.
If necessary, add
corrective pins. Remove excess glue with a cloth. Frozen drop of glue on the
surface,
will bring a lot of inconvenience when finishing.
Pay due attention to the duct. These pins are positioned
easily with any
material thickness of up to 2-3 mm. the thickness of the duct.
Place on a flat surface and attach the load.
7. Begin Bonding next couple of details in the previous paragraph .
Duct inlets cut yourself, based on the characteristics of the attachment.
8. Allow to dry glue. Patience. Pasting from one model AeroTetrisa goes up to 5
hours or more.
Please note, as gluing when needed to connect a pair of 2-3-4 parts, since the
center of gravity, there is a weight not simply.
You can use the strap.
When using the strap, be careful. Expanded polystyrene is quite soft material
and excessive
force can damage it, deform. In this case, use of waste material
as washers. The factory set them enough.
9. When gluing, check the geometry and alignment of the model.
Also use the slipway when assembling, similarly when assembling balsa models.