Sometimes I like to look at scale models before they are primed and painted. A naked scale model reveals the variety of materials and fabrication methods used in the model build.
Some model parts are 3D printed. Others are hand built out of various types of plastic material, foam or molding compound. Still others are cut out of metal using CNC machines. (For more info on model making materials check out this previous blog post. ) The parts are fastened together to create the body of each custom model.
Right before the scale model is sent to the paint booth for a coat of primer, I like to take a picture of it “naked”. The raw beauty of a hand built item is powerful. Once it is covered in paint a person can easily forget the intricate work involved in creating a 3 dimensional object from scratch.
Check out these projects in their uncovered form versus how they look after painting and finishing. See if you agree with me that naked scale models have beauty to them.
Often times at KiwiMill a scale model turns out to be a work of art in itself. An excellent example of this is the Taper Fill Hip System. This product is an implant that is inserted into a person during hip replacement surgery. When made into a model at 3-4 times its original size, the beauty of the design and its functionality really come to life.
The model was commissioned to show how the implant works inside a human body. The various parts of the device were created in a modular fashion, so they could be taken apart and put back together during a demonstration. Model Maker Mike chose magnets to connect the various pieces of the implant to each other. This makes it easy for a salesperson to connect and reconnect them over and over again.
The various parts of the scale model were made from 3D printing and CNC milling and routing. The finishes were particularly important in this model build, as they illustrate how the product functions. For instance, the heavily textured areas that you see in the model are used in the real product to encourage human tissues to attach and grow after implantation.
The high gloss on the pink socket you see in the model is a mirror-like finish, achieved by placing a clear coat over the painted surface. The shiny chrome surfaces you see in the model were created using vacuum metalization.
All of these carefully rendered surfaces come together to create a an incredibly visually appealing scale model. The modular features of this particular model only add to its usefulness.
I recently noticed some jelly-like blob soaking in the shop sink. What? It prompted a discussion with, Tom, one of our model makers, about making a mold for models. I grabbed the camera, took some pictures, and wrote the process down in a notebook. Here’s what I came up with:
Choosing the object you want to make a mold of, you determine where you want the “mold line” to go. This is the seam that will need to be disguised after the molding takes place. Using clay, you make the mold line on the object, then place it into a well sealed custom box and pour rubber up to the mold line and let set. After that half dries you peel off the dried rubber and reposition the object in the box in order to pour rubber on the other half. You peel the hardened rubber off the other half and now you have two rubber pieces that fit together with the cavity in between them representing the object you want to mold.
The rubber mold is sprayed with mold release and again placed in a special box to keep it rigid, the two halves forming a whole. An opening, called a gate hole, is created where the resin will be poured in. Air holes are made in the rubber mold as well, where hoses or straws will be poked through to allow air bubbles to escape during the hardening process.
Resin is mixed with hardener and then poured through the gate hole via a tube. The box is then placed in a pressure chamber to compact and press the resin into all of the nooks and crannies of the cavity. When the resin has hardened, the box is opened, the rubber mold peeled off and the molded part is then rinsed off in the sink. After that the mold lines are smoothed over and the molded part is ready to be primed and painted.
One of the more appealing characteristics of model making is the excitement generated around each new project. Most model makers appreciate the fact that their work is varied. Each assignment brings with it research, skills, materials and building techniques that were not necessarily used on the last job. Each time a model shop moves on to the next project, it’s a fresh start.
So exactly how does a model makerapproach an assignment once the sales staff brings in a new job? First, as much information as possible is gathered about the model. Most importantly, what is the purpose of the model? What will it be used for? Sales tool, developer’s presentation, instructional or educational purposes, visual impact? How many models are needed? How big or tiny will the models be? (Scale).What level of detail does the client want shown on the model?
This beginning stage of the project also means gathering up as much information as possible about the physical details of the item being modeled. This can include photographs, sketches, blueprints, 3D drawings, or the real object itself. It often involves internet research, interpretation and forensic-like piecing together of missing details.
As this information gathering stage is being completed, the model maker begins to visualize the finished product in his head as a whole. What will it look like when completed? Then he mentally takes the model apart piece by piece and begins to imagine what materials will be used to make each part. Reversing the process, the model maker reassembles the project in his head, determining how each piece will be fastened together – glue, rivets, solder. Brainstorming meetings, sketches or detailed CAD drawings might be used to aid this pre-assembly/reassembly stage.
Then the model maker has to think about the order the parts should be made in. What sub-assemblies need to be built? How will the parts be grouped for painting? Once the individual assembly jobs are assigned to different model makers, it’s time to get started on the actual building of the model. Active construction is what model makers are best at, but throughout the process, a well trained mind for research, 3D visualizations, and problem solving skills is essential.
Seems like every holiday season KiwiMill is asked to make a custom truck model for a very special client. Our model makers love this type of project. Who wouldn’t?
This year’s custom trophy truck was based off a store bought RC 1:10 scale truck named the “Yeti”.
The outside shell of the Yeti was removed and a custom one designed in its place. A photograph of the real truck was used to take exact measurements, which were then adjusted slightly to fit this particular off-the-shelf truck frame. The custom shell was drawn up in Solid Works.
The computer drawings were then used to vacuum form the custom truck shell.
A custom chassis was assembled under the base using ABS plastic. Other accessories were hand built including the light bars, fire extinguisher, gas tank, and ratchet straps.
The interior of the truck model was hand built as well. A plastic figure was placed inside. It wore a custom fabricated and hand painted helmet to match the one the real life owner and driver of the vehicle wears.
The custom trophy truck model was masked off and painted from the inside. Vinyl labels of the logos and sponsors were applied to the finished surface.
The truck was then mounted on a base made out of rolled, welded steel that was painted to resemble the dirt hills the real truck is driven on.
The final product turned out to be a great surprise for the client. His own custom trophy truck model, built to replicate the real one he owns and races. Very cool gift!
One of the more obvious features that sets great models apart from mediocre ones is the paint job. Everyone notices it. A model makers expertly applied paint job doesn’t automatically make a model high quality, but you won’t achieve model perfection without one.
A lot goes into the painting process. Even though it is often thought of as a finishing touch, it’s actually given a good deal of thought early on in a model build. Right at the beginning, during the brainstorming and design phase, consideration is given to the paint colors that will be needed for the different parts. It helps determine the order that the model will be assembled in. Parts are generally painted before being assembled, not after. So it’s not a final step in the process after all.
What Kind of Paint Is Used?
There are different types of paints for different projects. Ourmodel makersuse enamel, lacquer, epoxy, automotive and model paint. Models need paint that looks good, stays on and is quick drying. Less consideration is given to the hardness of the paint as most models are not subjected to outdoor elements, or scrubbed clean on a regular basis. Paint has two, sometimes three, characteristics that determine how it will perform: pigment, binder and solvent. The pigment will determine the color hue, the binder is the vehicle that sticks the color to the model and the solvent affects the flow or spread-ability.
Once a particular paint is chosen, the model is first given a coat of primer. Primer is a grey, sand-able substance that helps the paint stick to the model. It is flat rather than glossy in texture in order to show all the details of the model, and point out any scratches or blemishes that may need to be filled or sanded out. Sometimes the primer itself will smooth out light scratches, other times a spot putty is applied to deeper flaws in the surface. When primer has been applied, filled in and sanded the model is perfectly smooth and ready for a coat of paint.
How Is The Paint Applied?
The delivery method of the paint is most often an air brush, HVLP (high volume, low pressure gun), or spray can. Most paint is applied in some kind of mist form. Rarely is a brush used, except for the tiniest details. Masking is used to cover parts of the model that are not ready for painting. Special tape is used for this purpose. While applying paint, it’s also important to know how different paints will interact. Some types of paint will have a volatile reaction with each other depending on the type of solvent that is used in them.
Once the paint has been applied with an expert hand and eye, it needs to dry properly. While some paint will be dry to the touch almost immediately, the surface underneath may still be damp. A model may seem dry when the solvent in it hits the air and evaporates, but curing is the polymerization of the paint binder (a chemical process that may take much longer). Ideally a freshly painted model should sit for a couple of days before packing or wrapping for shipment.
The paint job on a model has a huge impact on its appearance and like-ability. It makes sense that it is given important consideration from the onset of a project, all the way to its finish.
KiwiMill has the ability, in house, to add motorized and electronics features to your models. A few weeks ago, we delivered a model to a customer that required a lot of power and numerous interactive features all controllable by buttons on a panel in a museum.
Custom Electronics Box & Power Supply
Adding electronics to models comes with its own set of unique challenges. Our customers demand their models work reliably and want to make sure the power supply is UL listed to ensure it is safe to use in their displays.
Some of the issues we run into in our models:
Multiple Voltage Requirements – models often use off-the-shelf electronics (sound makers, motors, lights, etc.) that require multiple voltages on a single model.
High Current Requirements – While LEDs use little current individually, today’s modern superbright LEDs can use upwards of a watt of energy each and, when you string 50 or 100 of them together, they use more current than a typical power supply can provide. Motors can also use a lot of current and require a robust power supply.
Were Do We Mount All These Things – Break-Out-Boards, Controllers, SSRs, power supplies, etc… where do we mount all these things so the parts won’t get jostled and the customer won’t get shocked?
Our solution is a custom ATX power supply in a custom made sheet metal box. An ATX power supply provides multiple voltages (3.3V, 5V and 12V) which is the power requirements for almost everything we build. Not only do they put out multiple voltages, an ATX power supply puts out A LOT of current. We can get a 1,500 watt power supply just in case we need to light an entire city all at once! On top of that, the ATX power supplies we buy are UL listed to ensure they operate safely. A good ATX power supply is also built to last a long time and includes a fan that will keep the electronics in the box cool.
Below are some pictures of our CAD design for this custom ATX power supply and electronics box, and pictures of the finished product. There’s also a picture of a much larger box that has hundreds of wire connections coming into it.
Fiber Optic Light Source
This one was a little easier.
The problem: anything that holds a light-bulb is designed to allow light to escape as much as possible. A light is designed to provide humans with light, after all. We need to fully contain the light and direct it toward a bundle of fiber-optics.
The solution: A custom designed fiber-optics light source. This is nothing more than a sheet metal box with a bracket to hold a standard light socket. The cover contains the light in the box. We used a 60W LED spotlight to direct as much of the light into the fiber bundle as possible.
Are you entertaining the idea of a scale model for your sales office, trade show display or company training, but are unsure of exactly what you’re looking for? While there are customers who come to us with exactly what they desire – right down to the scale, level of detail and finish – it’s not unusual to have lots of questions about scale models in general, and the process of purchasing one.
Our team at KiwiMill can help guide you in the process of choosing a model; determining what your goals are and how best to achieve them through a scale model presentation. There are endless options for portraying a product, place or concept via modeling. Narrowing your options down to the choices that will work best for your particular situation, is something we have lots of experience in. With model makers on staff that have 20+ years in the profession, we feel confident in our ability to present you with an idea that will fit your particular situation.
You may have a product that would be best displayed in a particular scale, as a cut away, or with lighting and movement to highlight particular attributes or abilities. It might make sense to have multiple models to show various design options, or just one model that transforms into different configurations.
Size or scale is a consideration that often requires additional clarification or guidance. Some features will not display correctly in a scale that is too small, for example. Larger scales have their own considerations, such as the need for very realistic detail in order to have the impact necessary for a quality display.
The amount of detail to put on a model is another area we can offer guidance with. While it might make sense in many instances to have as much realistic detail as your budget allows, there are circumstances where it might be unnecessary and even visually distracting to go that route. This is where our model maker’s artistic eye and vast experience might help steer the direction of the project towards a mutually satisfying outcome that otherwise would not have happened if our input wasn’t offered.
There may be questions about a model that do not involve artistic interpretation, but are more practical in nature. A client may be interested in learning about how a model can help train personnel on procedures, logistics or safety issues. We can come up with a model design that helps simplify or clarify a process, cutting down training costs and increasing efficiency.
If you have entertained the idea of a model but aren’t sure what it can do for you, or you aren’t sure what your options are in terms of types of models and their uses, give us a call. (866.783.8612). Our model makers like to talk about models, and your project or concept, matters to us. Finding the right fit between a client and a scale model that communicates its message correctly, is part of the service we offer. You don’t need to know exactly what you want in order to start the conversation.
KiwiMill has built a reputation for making accurate, visually appealing scale models on time and within budget. When new clients realize the value of the product we give them, they often become repeat customers. Repeat business allows a relationship to develop between client and model maker, which ends up benefiting both parties.
Scale models are often a mix of artistic vision and cut-and-dry accuracy. A product model may be an exact replica of the real thing, right down to each nut and bolt. Most custom models, though, are artistic interpretations that represent the overall feel of the real thing. They convey the essence of the object being modeled.
This interpretation is what creates a successful model maker. A keen artistic eye, experience with the properties of the materials being used in the build, and expert fabrication techniques are what set apart master builders. It’s also the reason to establish a long-term relationship between model maker and client. Ideally there should be a good fit between client’s expectations and the style of the model they are given. A good match means an outcome that everyone is satisfied with.
It is not always easy starting a new relationship with a model maker. Custom work is exactly that. There is often no previous example in a portfolio of exactly what the outcome will be. There is an element of risk involved. That’s another reason why once a client finds a reliable, skillful and ethical model builder, it pays to stick with them over time. KiwiMill strives to be that “go to” model shop; a company you can come back to for the same quality execution each and every project.
Check out this collection of 3D printed parts from recent jobs. KiwiMill uses an Objet 3D printer to create 3D printed pieces.
Our scale models are never completely 3D printed. The resin used in 3D printing is durable, but still works best in combination with other materials like ABS, brass, acrylic or tooling board.
Parts that are good candidates for 3D printing in our shop are those which are intricate, relatively small and fairly detailed. It makes sense to create larger, simpler, bulkier parts by other methods.
Below are pictures of recently developed 3D printed parts:
Part of quoting custom model work is determining how long the project will take to build. KiwiMill gives an estimated completion time in each quote. The time it takes to complete a custom model is based on a number of factors.
The number one factor influencing project length is client need. Many of our projects have to be finished in the shortest period of time possible. There are deadlines for trade shows, sales presentations, corporate meetings and museum openings. Therefore, one of the first questions we ask our clients, after figuring out the purpose of the model, is when and where they need it delivered.
Meeting the client’s deadline is of the utmost importance. Before a job is accepted it has to be agreed upon that the project can be completed in the given time-frame. No client will be expected to pay for a scale model that fails to meet its deadline.
As each custom job, by nature, is different from the previous, figuring out how many hours will go into a build is a complex process. KiwiMill does this by estimating the amount of time needed to complete each step of the project – from material acquisition, design time, fabrication, to assembly and finish – then figuring out how many model makers are available to work on it.
Once we make the commitment to a project deadline, everything possible is done to make it happen. Often this involves long days, over time and weekends. Sometimes it means a model will have expedited shipping (agreed upon ahead of time with the client). Whatever it takes to get the job done on time, and with high standards of quality, is the goal.
When there is not a hard deadline to work toward, the length of a project is still determined by estimating the number of hours each part of the project will take, divided by the number of model makers available under “normal” working conditions. The project length is usually quoted in weeks. It typically does not start until the information needed for the build are supplied by the client, along with a deposit where applicable.
When a quote is given, the completion time is based on the current work load in the shop. Our production supervisor schedules simultaneous jobs, and assigns project managers to each one. If you happen to need a model when there are fewer jobs currently scheduled, then the completion time will be shorter. Likewise, if you choose to have a model made during a very busy time period, the build time will be longer. By sharing this information upfront with the client, before a project is agreed upon, there are no surprises or disappointment.
Most clients understand that the building of a custom model is an artistic endeavor which does not follow fixed steps found in many other manufacturing processes. Each model is unique, as are the materials and fabrication methods that go into a build. In spite of its unique nature, model makers understand the expectation that the final product needs to be finished on time, every time. It’s the nature of the profession that most custom model projects will have tight deadlines, sometimes even highly unrealistic ones.
It’s been over two years since I’ve started spending time with model makers, and I am still struck by the variety of mediums they work with. Especially since I do the ordering for them!
Model makers who make custom models have a stunning variety of material they must be able to construct with, and just as many techniques to go along with that. Depending on the type of model – architectural, trade show, military, museum – and its purpose: sales, display, training, fundraising, etc., the actual substances used to create a model vary.
Our model shop works with all types of wood, several types of plastic, a variety of metals, molding compounds – even fabric. Just in the plastic category alone there are several different types, each with its own properties: ABS which is more resilient, acrylic which cuts beautifully on the laser but can break, resin which is the liquid plastic that the 3D printer uses, and styrene – an easily bonded staple of architectural models.
When determining what material to build with, a model maker has to decide what properties are best suited for the purpose intended. If the model will be displayed in a clear box and never touched, then delicate, intricate and the most realistic looking materials can be used. This is rare.
Most of our models are meant to be touched and handled by the viewer and need to be built with substances that can hold up to this kind of treatment. Often times this means a mixture of different plastics and metals. The metal ends up providing a solid skeleton for the model that more detailed pieces can be “hung” from.
At the extreme end of durability are models that must provide motion, simulate movement or light up. These working models require material that can withstand the friction, and sometimes heat, involved in the moving parts. It may include pulleys, actuators, motors, gears, or electronics that need to be properly housed in the correct materials.
Besides knowing what material to use for which model, a model maker needs to understand how to cut, shape, and cover the chosen substance. Paint doesn’t cover every material the same way. It’s also important to choose the correct fastening method. A model is usually made up of many parts, each of which not only needs to be accurately formed and covered with a properly adhering finish, but then has to be securely attached to the model as a whole.
Knowledge of all the different types of materials that may go into any given model, takes time and practice. Successful model makers are well versed in the various fabrication choices, methods and techniques that go into a custom model. They get this way by actual immersion in the craft.
It’s been a couple of years now since KiwiMill started making 3D printed parts for our models. It took some experimentation to get this model making tool working for us, but we have settled into a nice rhythm in terms of its use.
About 70% of our jobs now involve some degree of 3D printed parts. At the beginning of a project, our model makers decide what materials they will use to build each part of a custom model. Several factors are considered when deciding what pieces will be fabricated on the 3D printer. The complexity of the part, its use on the model, it’s size and how quickly it needs to be produced are some of the considerations.
The 3D printer is an excellent choice for complex, intricate parts. Once the time is taken to draw up the part in CAD, the printer can effortlessly build a detailed object with great accuracy. Even when factoring in the time it takes to clean support material from a finely detailed piece, it’s often worth the prep work to get a final product that has all of the desired cosmetic effects intact.
Depending on the over all model’s purpose, 3D printed parts may be too delicate for use in a project. They aren’t the best choice for moving parts, or places that need to endure a high degree of impact. However, they may still work well alongside more durable materials such as ABS, metal and tooling board, adding detail to an over all sturdy model.
Not that 3D printed parts can’t be strong. Large, solid parts, with less intricate detail, can be quite durable in nature. However, they are often cost prohibitive. The resin used to create objects on the 3D printer, is relatively expensive material. It doesn’t make sense to 3D print large pieces that can otherwise be hand-built, CNC milled or routed out of another material.
The exception to this would be if timing is a factor. If the item being fabricated can be drawn in CAD, printed, cleaned up and finished quicker than a hand build, it may be chosen in a situation where a deadline is looming.
KiwiMill has yet to completely print a model. Even in cases where the final product was made up mostly of 3D printed parts, it still involved other materials and fasteners holding the various parts together. The 3D printer has not replaced a model maker, either, though we joked about that happening when it first arrived. It is simply another successful tool of the trade that we have fully integrated into our repertoire.
Recently I watched our model makers take perfectly crafted scale model buildings and purposely mess them up. My curiosity was piqued. Why painstakingly create a line drawing on the computer, laser cut it, precisely assemble and finish the parts into an architectural model, only to “dirty’ up its perfection?
It turns out that a certain segment of architectural models – historical models – are given what is called weathering effects. Why? The intent is to represent the impact of the elements on an object, in order to project the sense of time, and place, that a historical scale model must provide.
The artistic application of weathering techniques attempts to simulate – not duplicate – the natural ageing and wear process on the buildings, vehicles, roads, and other inanimate objects represented on a particular historical model. Things like dirt, grime, sun fading, paint wear, spills, stains and rusting, must all be scaled down to size using well honed modeling techniques.
In addition to developing specific methods for applying weathering effects, a model maker must do the historic research necessary to match the ageing process with the time period the model is attempting to capture. For instance, a train run on burning wood will leave markings that differ quite significantly from a coal powered machine.
Model makers can enhance their expertise at weathering models by studying the world around them – noting the textures, colors and formations of real life wear and tear . Once you pay attention you may notice that everything is subject to weathering – grass isn’t green, asphalt isn’t black, houses are different shades depending on sun exposure and vehicles have signs of use soon after they are purchased.
Our perception of the world is that it is much more brightly colored and distinct than it actually is in reality. Weathering techniques take a fully painted and detailed model and use filters, washes, dusting, and other techniques to give the desired muted effect that more closely mimics real life. Signs of wear like scratches, faded paint, rust and stains further enhance the effect.
It’s a fascinating process watching a model maker take a flawlessly constructed architectural model and add blemishes to it. In a historical scale model, it is this artistic application of ageing techniques that ties the display together and gives it life, and the feeling that it’s accurately captured a moment in time.
Like most scale model shops, KiwiMill prepares free-of-charge custom model quotes to anyone inquiring about a project, big or small. Sometimes we give ballpark figures over the phone or email, based on basic information about model purpose, design, size and detail level. These quick estimates can be given for model projects that are similar to ones we have done in the recent past. Initial rough estimates can help identify whether there is a sufficient budget to proceed with a formal written quote.
Most custom scale model inquiries go through a lengthier process to determine the costs involved. First, there’s an exchange of ideas and information with the client, then a bit of research and brainstorming, culminating in a formal, written quote. The quote usually spells out what will be provided by the model makers – over all design, materials, functionality, details, accessories, finishes, and any mounting, bases and crating options included. It also addresses timing and what is required from the client to start the job in terms of data and initial financial investment.
Before generating a formal quote, our sales staff addresses the inquiry: receiving the request, asking clarifying questions, and collecting any drawings, photos or additional documentation provided by the client. The more information that can be gathered about a project, the more detailed and accurate the quote will be. This initial exchange goes very quickly, as the goal is to get the project in the hands of our model makers to assess as soon as possible.
KiwiMill likes to connect potential projects with a model maker fairly early on in the quote process. Talking to an actual model maker has benefits for both the client and the model shop. First, a model maker can help clarify the scope of the project. By talking with a client, our model makers are able to understand what the model is required to do, and in many cases, help determine what the best approach is to meeting those goals. Clients sometimes know exactly what they are looking for in a scale model, but more often than not, an exchange of ideas helps narrow down the options to one that best fits the client’s needs and budget.
Secondly, our model makers can begin thinking about how they would go about the build of a custom model as they talk with the client about their project. This initial thought process will aid them when it comes time to prepare the actual quote. There is no magic formula used at KiwiMill for generating quotes. Each project is given careful consideration in terms of materials used, fabrication methods chosen, size and complexity of the model, and the engineering of moving parts or other special effects. Another major consideration is whether parts for the model will need to be drawn up in a CAD program, before construction can start. Timing may be a factor as well; if the job needs to be rushed, then vendor supplies and overtime costs need to be considered.
A detailed quote can be prepared after the project is defined, the accompanying documents are studied, availability of materials are researched and fabrication methods are decided upon. This process may sound complex, but it assures our client that what they are getting is what they expected and desired. It also does not need to take up a lot of time. We pride ourselves on getting quotes out very quickly, without sacrificing the attention to detail and customization of each project. Well defined, personalized and accurate quotes are a service we are happy provide to each and every one of our potential customers as an initial sign of our commitment to quality service and performance.