Scratch Building Articles:

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|Scratch Build Seminar 1 - Getting Started|

|Scratch Build Seminar 2 - Basic Tools|

|Scratch Build Seminar 3 - Materials|

|Scratch Build Seminar 4 - Putty|

|Types of Putties|

|General Putty Information|
|Body Fillers|
|Epoxy Putties|
|Polyester Putties|
|Glazing Putties|
|Super Putty|
|Putty Warning|

|How to Use Putties|

|Choosing the Correct Type of Putty|
|General Application Information and Preparation|
|Application|
|Shaping Sanding|

|Paint Prep|

|Scratch Build Seminar 5 - Styrene|

|Choosing the Correct Piece of Styrene|
|Cutting|
|Attaching/Adhesion|
|Sanding|
|Bending|
|Paint Prep|



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Scratch Build Seminar 1 - Getting Started

The first thing to cover is getting started. To get started you need to develop an idea. Then start to create a design. The difference between an idea and a design is designs are hard copies of an idea for all to see. An idea is a mere thought, or creation from the depths of your imagination and brain activity of electrical neuron stimulus. A design on the opposite side of the table is the language an idea communicates through.

To create a design you need to take out a piece of paper and sketch. It doesn't matter if you are an amazing artist or cant draw a stick figure, just get some lines down on paper. The eye needs to be trained to see how things are composed. Every piece of matter is composed of shapes. Once you see the shapes in objects it is all down hill from there. If you can see how an object is put together with simple shapes, then you will be an expert scratch builder and designer in no time. The key to scratch building, which cannot be emphasized enough, is seeing how objects are made up of shapes and proportions.

Know to understand something you have to understand the principles behind it. This is why I am covering the fundamentals of scratch building. Without these you will forever be scratching your head. Now behind principles are roots. The roots are the ground for the principles. I will explain how and why seeing shapes inside objects is important. If you can see how an object is made up of shapes, then you will be able to see how to translate that object into a variety of pieces to build up. If you can manipulate the object in your head, or on paper and tear it down into the basic shapes then you can take those shapes and trace them on to your material and build the object. In other words, if you can see the simple shapes in an object, you can see how it was built, then you can figure out how to reconstruct it yourself.

This ability wont come over night. You will train your eye to notice these simple shapes. There are three simple shapes, triangles, ellipses, and rectangles. To train your eye, stare at an object and break it down into those three simple shapes. Then translate it onto paper. This exercise will give you a more keen eye and noticeability to how things are constructed and will be the essential fundamental for scratch building.


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---------------------------------------------------------------------------------------------------- Scratch Build Seminar 2- The Basic Tools

This is the second installment of the "Scratch Build Seminars" which will cover the basic tools. More extensive used of the tools and fabrication will come later.

When you are scratch building, you have to change the channel on your mind. Forget everything. There's a saying "Think outside of the box", its a good saying, but is also limiting in the ideology of scratch building. If there's a box for you to think in, then somebody has told you something and you've been limited. Even if you are thinking outside of the box, you still look back at those restrictions. So the correct saying is "Think as if there is no box". These seminars are not a rule book for scratch building, only a guide. Scratch building is only limited by your imagination, and THAT is your key tool.

Not all tools are intangible like your imagination; many tools are actually built, or bought. Each tool will have an application and if there isn't a tool that meets your application, build it. Don't be limited buy what tools are available to purchase, walk through the craft store and see what you find. You'd be amazed at what other crafts use that can be applied to modeling.

The obvious tool is the X-acto knife. New blades are always better than dull blades, but don't go throw away those used blades they are useful. New blades are really good for cutting out thin material such as: .020 or thinner styrene, paper, decals, tape, bare metal foil. Dull blades are good for cutting thicker plastic. The broken tip allows the blade to score the plastic and remove material. Whereas the sharp blade separates, spreads, and cuts apart material. Using the back of the blade also achieves this effect. The horribly dull butter knife blades can be used for spreading putty.

The most important tool used is a metal ruler. A good accurate ruler is very important for making sure dimensions are correct. Measure three times, cut once, and sand a little. The reason aluminum or stainless steel is preferred is that it is used as a cutting straight edge as well. Don't try to make straight cuts without a straight edge, they will come out bad. The straighter the cut, the more precise it is. Use a straight edge.

Files are an asset to any scratch builder, and modeler. Find the least expensive set of files you can get. There are rumors that more expensive diamond files, but the difference goes unnoticed. Files will be broken, ruined, filled, and go dull. Get a lot of files too. The more shapes and sizes, the quicker and easier your work can be.

Liquid model cement should be used whenever gluing Styrene together. Liquid cement melts the plastic together. You get a better, strong, and more unison joint. If you need a thick piece of Styrene you can laminate thinner sheets together to create this thick piece with the liquid cement. Each liquid cement has a different evaporation rate. Often times a slower evaporation/cure rate works the best. The slower evaporation allows the Styrene to melt more for a much better bond. Testors Liquid Cement has the slowest cure time, and is the strongest. Tenax and Ambroid Pro Weld have a very quick evaporation time and do not allow a lot of work time.

Paint brushes of varied sizes can help with different application sizes when applying liquid cement. Small paint brushes work for the nice tight details. The paint brushes need to be some sort of hair. Nylon or plastic bristle brushes will melt.

Syringes can be used with liquid cement for large applications. Fill the syringe with liquid cement, and apply it over a large area. This allows the cement to work and not evaporate as fast.

Tube cement, its messy. It cannot be spread thin easily, nor does it melt the plastic well. Often times it can melt the plastic too much. Liquid cement is highly recommended over tube cement.

Superglue, also known as Cyanoacrylate is a very quick curing instant glue. There is liquid superglue, and gel superglue. They both come in tubes. The model "grade" superglue is know different than the superglue at the dollar store. Superglue gel mixed with a little sanding dust or baby powder works great for filling gaps. Superglue in its liquid form is also useful for attaching unlike materials, such as resin.

Putty is often times misleading. While it may be simple to mix and sand to shape it can cause lots of havoc. Stay away from one part putties for anything. They will cause lots of trouble down the road. Always use two part putties because they do not shrink and are much more durable.


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---------------------------------------------------------------------------------------------------- Scratch Build Seminar 3-Materials

Resources and materials are what is needed to build from scratch. Kit bashing is often misunderstood as scratch building. Building from scratch is building from raw materials. Some people can get into terminology and say that the term raw means "unrefined plastic polymer", not styrene sheet. Don't get caught up in the terms. Scratch building is building from basic materials available. Kit bashing is when you use several parts that are pre made or from another kit.

Materials for scratch building come in several different shapes, colors, sizes, and substances. Some materials are metal, others are plastic. To choose your material, you need to decide which material would best suit your application. Some materials have better uses than others.

Styrene is a very common material in modeling. Styrene is plastic. The most common producers of styrene are Evergreen and Plastruct. Each company has their advantages and disadvantages. Don't stick to just one manufacturer of styrene; use which ever it takes to get the job done. Evergreen offers sheets, strips, tubes, squares, rods, and offer these in larger amounts than Plastruct. Plastruct offers several different shapes that Evergreen does not, such as: triangular rod, trusses, pentagonal rod, hex rod, and sometimes smaller diameter rod than Evergreen.

Styrene has unlimited uses. It is easy to cut, bend, shape, sand, paint, fill, and glue together. It can be cut with an X-Acto knife, or scissors. Bend it with solvent, glue into shape, or heat it over a flame. You can laminate several pieces together and sand it into a shape. Using styrene is a much better alternative to putty as it has a less likely tendency to crack, shrink, or lose shape.

Brass is and often used material in scratch building. Brass is slightly expensive, but is often better in some applications. Brass comes is several different shapes, but is not a readily available as styrene. K&S Engineering, along with their partner Special Shapes produces a lot of brass shapes and sheets. Most hobby shops have a K&S Display to sell brass and aluminum.

The common use of brass is where something needs to be rigid and strong. Brass can be cut, soldered, and shaped with a hammer and heat. Cutting brass depends on the shape used. If you're using tube, you can use a tubing cutter, or Dremel cutting wheel; same works for rod. Sheet can be cut with sheet metal sheers. Soldering is the best method of attaching brass together. (A more in depth explanation of soldering and its uses will be in a seminar later.) Shaping brass is not easy, but can be done with practice. Using many different types of tools such as hammers, tucking forks, hammer forms, bucks, and torch brass can be shaped. The best advantage of brass is that it can be chromed.

Sometimes you may have to combine materials. Like a brass rod inside of a styrene tube to give the styrene some strength; other times neither resource works well. Take a look around a craft store for ideas of different materials. Everything has multiple uses. Once again "think as if there is no box to think in".

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---------------------------------------------------------------------------------------------------- Scratch Build Seminar 4-Putty

This seminar will be very in depth as it often causes the most trouble. People often have difficulty knowing which putty is the best for them and their application. Many time people choose the wrong putty due to lack of knowledge about them, so hopefully this will help you pick your putty.

 Types of Putties

General Putty Information
Putties can be very useful, but they can also turn on you when after you paint. There are several varieties of putties, each have their pros and cons and each have their special uses. One part putties while they are the easiest to use for a lot of people, they can really make you cry after you paint. One part putties dry by evaporation of moisture. This will cause shrinking, and the shrinking continues on over a long period of time. After painting the putty continues to shrink, and can ruin a perfect paint job. One part putties should be used for fixing very small pinholes and scratches. Bondo's Spot/Glazing Putty is intended for just that, fixing little tiny spots, and glazing scratches. Many people have thought that the Spot/Glazing Putty can be used for modifications, and filling. Unfortunately people are blinded by how easy it is to use and cant see the aftermath. Don't try using one part putties where a two part putty should be used just because you don't want to mix. If you do, you will end up spending more time in the long run trying to remove the putty and fix your mistake. Caution: Stay far away from one part oil base putties. When they are wet sanded they fall apart, plus they are incompatible with many types of paints.
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Two part putties should be used for filling, major body modifications, and other stuff. There are several types of two part putties; Bondo Body Filler, Evercoat Euro-Soft, epoxy putties, and polyester putties to name a few. Two part putties are much better than one part putties. Two part putties require the base, and the catalyst. By having two parts the putty cures chemically instead of physically. Since it cures chemically it cures much faster, creates a much stronger bond, doesn't shrink, and doesn't absorb paint. Since two part putties are much stronger they can be used for filling without any problems. Two part putties are recommended as much as possible. If you have a couple scratches and pin holes, wait until you mix another batch of two part putty and fill the holes and scratches that way. You will have a much better result with two part putties. Another benefit is they don't absorb moisture when wet sanding (some one-part putties do).
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Body Fillers
Body fillers are excellent two part putties. They cure quickly, dry hard, cure chemically, and best of all they sand easily. Body filler's main benefit is that they sand very well. When they cure they are hard enough to withstand working conditions, yet soft enough to cut with a razor blade or hobby knife. Sanding is extremely easy with body fillers. When cured it can be molded into the desired shape with some 100grit sandpaper, and then smoothed out with some 400-800grit sandpaper. Side Notes: Bondo Body Filler does not stick to plastics. Evercoat Euro-Soft is an excellent two part glazing putty that does stick to plastic. Evercoat products are higher quality putties but they are much finer and sand smoother than Bondo products.
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Epoxy Putties
Epoxy putties are superb for attaching pieces where aesthetics are valued. Epoxy putties are super adhesive and super strong for attaching pieces back together. They can also be sanded into a desired shape. So if you need to put something back together, but the joint needs to look good, use epoxy putty instead of epoxy. There are several grades of epoxy putties. Marine and automotive epoxy putties and model epoxy putties. There are several flavors of model epoxy putties that come in a variety of grit. The grit is determined by how smooth, and how fine the particles are. Marine and automotive putties are almost as good as model putties and comparatively are more efficient because of the cost. Model brand epoxy putties are normally more expensive and harder to find. Marine and automotive putties are less expensive and easy to find and do the job just as adequately. The downside to epoxy putties strength is the ability to be sanded. Epoxy putties are extremely hard to sand since they are very tough, and they also produce a very fine dust and easily clog up sand paper. Also once its on there and cured, its not coming off easily. However, even though they are harder to sand, they can be formed into the desired shape before they cure. The recommended use is for creating aesthetically pleasing joints, not filling and shaping. Epoxy putties also stand up to many varieties of solvents.
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Polyester Putties
Polyester putties are two part putties that are a similar cross between body filler and glazing putty. Polyester putties can be sanded very smooth and are very good for filling, and shaping. They sand very easily, but are very durable. Just like body fillers, they can withstand many varieties of paints, but not solvents. The glazing factor is they polyester putties can be spread very thin and then sanded smooth for a nice glaze coat. If you need to fill tiny pin holes or scratches polyester putty is recommended because it will not shrink like a one part glazing putty.
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Glazing Putties
Despite the easy use, these putties can come back to haunt you. Many people think they these putties can be used for filling, shaping, and "building". That is a very misleading interpretation. Glazing putties use is all in the name, glazing. Don't try to use it to fabricate. One part putties shrink; the more you use, the more it shrinks. Glazing putties are decent for smoothing plastic joints, or mould lines. Once again, do not use one-part glazing putties for building; the results will be disastrous after painting. When painting a really good sealer should be used because one part putties absorb the moisture and reducers out of paints. To be safe, and to save time, don't use one part putties. One part putties lead to disaster 75-80% of the time.
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Super Putty
There isn't a real name for it, so we will call it super putty. Super putty is a good way to make super strong CA joints. All that sanding dust that you make from plastics and putties isn't a waste. When you use CA for a joint sprinkle some of the sanding dust on the CA while its wet and it will create a super strong joint that is shapeable. Its best use is for attaching styrene together. Its almost like a superglue filler. Its very handy, but not an alternative to a filler or epoxy putty.
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Putty Warnings
This is the most important part to using putties, its about your health. ALWAYS wear a respirator, even when sanding. The vapors (when mixing) and particles (when sanding) can get in your lungs and affect your brain cells. A dual cartridge respirator is recommended, if you do not own one you should invest in one. They only cost about $30 and can be purchased at many home improvement stores. The paper particle masks are only efficient when sanding. Be sure to mix the putties in a very ventilated area. Now don't let these warnings scare you from doing body modifications, or using putties, just play it safe. The warnings on the putty labels warrant death, and other illnesses. Those warnings are a little drastic, but always keep your health and safety in mind.
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How to Use Putties

Choosing the Correct Type of Putty
Think about the benefits and drawbacks of each type of putty, and then compare it your application. If you want to fill some holes, or build a body kit use a body filler or polyester putty. If you need to put to car halves together, use an epoxy putty because it creates a strong joint and can be aesthetically pleasing. If you fixing seams, use a polyester or two part glazing putty. Yet again, stay away from one part putties. Many people swear by Bondo's Spot/Glazing Putty but the long lasting results are displeasing and will cause a lot of agony.
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General Application Information and Preparation
Remove the paint, dust, grit, and grease. Putties adhere better to a rough surface instead of smooth surface. Rough up a metal surface using some 100-150grit sandpaper, rough up plastic surfaces with a 220 grit wet/dry sandpaper. If you are applying a putty over aluminum, steel, stainless steel, or other type of non-white metal you must spray a sealer or epoxy sealer/primer over the metal first. The resin in the putties can react with the metal and corrode the metal and make for a bad putty job. Primers are not sealers (putties can eat through primers too), be sure to use a good sealer or epoxy sealer/primer.
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Application
Read the label for instructions on how to use the putty. Each putty has a certain mixing ratio. Bondo Body Filler is usually mixed to a nice pinkish khaki color. Evercoat Euro-Soft is usually mixed to a nice light blue color. Epoxy putties usually are a one to one mix ratio of base to catalyst. Read the instructions on how to mix. After awhile you will become accustomed to the mixing ration and will be able to mix by eye. Go to the dollar store and pick up a large pack of popsicle sticks to mix polyester, glazing, and body fillers. Don't forget to wear your respirator.
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Shaping/sanding
Use a variety of automotive wet dry sand papers. Automotive sandpapers are the most accurate grade of sand paper. 3M automotive wet/dry sandpaper is excellent quality and can be picked up at most home improvement and automotive stores. Most automotive wet/dry sandpapers start at 220 grit, for that reason it is ok to use standard 100 grit sandpaper for the initial shaping of putty. Use a variety of sandpaper from 100 grit all the way up to 1500-2000grit.

Needle files are also superb tools to shape putties. Make sure you have a rag near by and consistently wipe the file on the rag every few minutes to keep it from clogging. Files load up very easily but are still excellent tools. To unload them either use a file card or soak them in lacquer thinner or another solvent.

Dremels can be used for the rough sanding. When you the roughed out shape with a Dremel use sandpapers and needle files to do the intermediate and final sanding and shaping. Only use the Dremel if you feel comfortable in using it.

Don't forget to wear your respirator.
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Paint Prep
Standard procedures apply usually. The only difference is that a good sealer should be used before spraying the primer. Some putties will aborb the primer and reducers and be cause for a variety of problems. If you don't want to spend the money on an epoxy sealer, there is a home improvement sealer called Zinser BIN. Zinser BIN seems to be a pretty good sealer so far, and is compatible with most primers. Zinser BIN can be found at Lowes and Home Depot for about $5 for a spray can.


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---------------------------------------------------------------------------------------------------- Scratchbuild Seminar 5-Styrene

 Choosing the Correct Piece of Styrene
Only you can decide on what piece to use for each application. This tutorial can only point you in the right direction while ultimately you choose where to go. All it takes is just some ingenuity, and creativity to be a fantastic modeler with styrene. For starting, a good base is to use some .020 Plain Sheet and .030" Plain Sheet. Those are the most commonly used sizes for constructing. However, different applications will require different thicknesses. Another benefit to styrene are the styrene strips. They are very easy to use, and are not very expensive. They have a variety of uses too. If you cut a piece to short, you can use a piece of strip styrene. The uses are infinite.

Styrene can be very confusing if you are just starting out. Often times people don't know where to start, but keep this thought in mind: "Use styrene to build up area's, don't build up with styrene only to remove material". Take a look at some progress pictures from a craftsman that uses styrene for ideas, inspiration, and knowledge.
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Cutting
Most styrene can be cut with a razor blade, a hobby knife or even a pair of scissors. Hobby knives and razor blades make the cleanest cuts. Scissors are best used for styrene sheets up to .030". When using scissors to cut .020"-.030" styrene sheet the cut is not perfectly smooth and needs to be sanded with some 220 grit wet/dry sandpaper. Scissors shear the styrene unlike cutting it. Each cutting tool has its benefit and only you can decide which tool is correct for the application. Do not use a Dremel. Dremels will melt the plastic and create an extremely messy cut.

Perfect circles can be cut using a compass or set of dividers. Put points in both ends of the dividers are compass. Calculate the radius of the circle to be cut and set the compass or dividers to that measurement. Place the compass or dividers on the styrene sheet and start spinning the compass/dividers around just like the way you would draw a circle on a piece of paper with a compass. This will cut through the styrene and create a perfect circle. The cut isnt perfectly clean so sand it with some 320 grit wet/dry sandpaper.
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Attaching/Adhesion
Styrene can be attached a variety of ways. For attaching the styrene to a material other than plastic you should use CA (superglue). For attaching styrene to plastic use a liquid cement (i.e. Testors Plastic Liquid Cement, Ambroid Pro Weld, Tenax Liquid Cement , etc.). Each cement has a different use, and the means of applying liquid cement vary as well. Testors is a very chemically hot cement and does not evaporate quickly like the Proweld or Tenax. The testors is very useful when laminating styrene sheets since it is easier to melt them together. Ambroid Proweld, and Tenax are great for small quick jobs, and they evaporate fast. Different methods of applying cement include small brushes, syringes, among other ways.
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Sanding
Like the putties use a variety of automotive wet dry sand papers. Automotive sandpapers are the most accurate grade of sand paper. 3M automotive wet/dry sandpaper is excellent quality and can be picked up at most home improvement and automotive stores. Most automotive wet/dry sandpapers start at 220 grit, for that reason it is ok to use standard 100 grit sandpaper for the initial shaping of putty. Use a variety of sandpaper from 100 grit all the way up to 1500-2000grit.

Needle files are also superb tools to shape styrene. Make sure you have a rag near by and consistently wipe the file on the rag every few minutes to keep it from clogging. Files load up very easily but are still excellent tools. To unload them either use a file card or soak them in lacquer thinner or another solvent. Another benefit to needle files is that if you have a piece cut out of styrene but it is a little off, you can use files to shape it correctly.
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Bending
Styrene can be bent over a flame, soaked in near boiling water and then bent, or rubbed with plastic liquid cement while bending. Bending styrene takes some finesse, and some practice. It's pretty easy once you get the hang of it though. The main way to bend styrene sheet and rod is with a flame. The cement is used for bending strips.
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Paint Prep
Standard procedures apply usually. The only difference is that a good sealer should be used before spraying the primer. Sometimes styrene will absorb the primer and reducers causing the styrene to expand and leave ghost lines and also cause for a variety of problems. If you don't want to spend the money on an epoxy sealer, there is a home improvement sealer called Zinser BIN.


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