Tag Archives: scale models

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Model Maker

Ask the model maker: What burning question do you have about model making? What is something you want to know about model makers, model making, or scale models? It can be a technical question, a price inquiry, a personal question or a how-to . Anything goes.

Leave your question in the comments section and it will be answered by a model maker (through me) by the end of the week.

KiwiMill Helicopter Model Build


A year ago, KiwiMill documented a 1/10 scale multiple helicopter model build, to be used as a reference in future, similar projects.

It began with brainstorming sessions to determine the materials and methods used in the process. Various approaches were suggested for going about the construction. Ultimately a design was settled upon using the same criteria as our other projects: consideration was given to the purpose of the helicopters (multiple trade show use), the scale, the amount of desired detail and a very challenging time frame of 8 weeks.

Once the over all fabrication methods were decided upon, our project manager, Dean, created a spread sheet time-line of our mission. This master schedule would be referred to throughout the project in order to maximize the time spent on each process, and to check that progress was staying on target for the due date.

model maker spread sheet

Drawings were made in Autodesk Inventor for the parts that were scheduled for machining. The helicopter bodies were CNC milled in-house, starting with foam blocks. Each shape was roughly carved on the CNC router and then coated in resin and re-machined for a finer finish.

The helicopter blades were CNC machined as well. A master was created out of ren board, then molded and cast into multiples and painted.

More detailed appendages were created with our 3D printer. These included the blade hubs, rear props, camera turrets and missiles:

The helicopter model parts were then assembled using a variety of techniques. Because the helicopters needed mounting points for display, a sheet metal skeleton was designed for each body to form around. This gave our model makers  a secure place to attach aluminum block mounts with brass sleeves, using bolts. Other parts were assembled using resin and solvent.


A special fastening method was used for the helicopters involving magnets. Magnets allowed for parts to be assembled and disassembled with ease by the client, and were used in the rotor blades, props & mounts.

In the final days of the project the helicopters were painted. The process required a look back at the original files that were provided in order to determine the exact location of the windows. Measurements were taken off the drawings to be used as reference points, but the final placement was done by eye. The helicopters were masked off and brought into the spray booth for application.

The last, yet very important, consideration that went into this project was the design of each case that would house and transport the helicopter models to various trade shows.  These road cases were custom created to fit each helicopter model  and its particular appendages. Padded jigging was built for the bodies to nestle into, along with designated locations for each removable part.

model maker

A couple of the finished products:

helicopter model

helicopter model

Model Maker’s How-to: Casting Cars

KiwiMill model makers recently designed a car model to be used for a sales display. The models will be used to showcase automotive paints for Hyundai. We chose to cast these from a carved resin master made from our original computer drawings.

A generic car body was created in Rhino 3D by one of our designers.

A  CNC milled resin master was created from this drawing.

CNC router model car

A negative mold  of the core was made from the master.

mold for casting car model


 This core was inserted in the mold to create a hollow space in the cars when cast.

mold for casting car model

 Three molds were made to cast the cars.

mold for casting model cars

pressure pot for casting model cars









                                The molds were put in a pressure pot for a smooth cast.

pressure pot for casting model cars


130 castings were created.

casr model cars

The bottoms of the casts were sanded smooth.

grinding car model

 The resulting cars will be painted various colors by our client, but here is one we painted.

 cast model car

Mistakes in Model Making

model makerModel making involves as much pre-planning as possible for each project to avoid mistakes later on. First, by determining exactly what the client’s needs are and determining the model’s over-all purpose. Where will it be used, how often and with what desired impact? Then, by brainstorming  ideas for the construction – materials and fabrication methods – model makers determine the best way to go about the actual build. Data about the model is also collected from the client and/or researched, including dimensions, structural details, colors and textures, in order to completely understand what is to be built.

All of this pre-work is designed to minimize problems further along in the model making process. Misinterpreting a client’s expectations can be a disappointing and expensive realization further into the project. Using the wrong materials for a part of the model can threaten its structural integrity. Utilizing a particularly complex fabrication process might cause the project to run over its deadline. Not clarifying conflicting measurements on a drawing might result in a less than accurate replica. Even something as simple as a slightly off paint color can derail a project during the important crunch time before a due date.

No matter how much careful planning takes place up front in a model build, there is always the possibility of mistakes along the way. Model makers don’t necessarily expect them, but they do plan for them and are trained at quickly fixing problems on the fly. Trouble shooting skills are essential in the profession.

Sometimes changes are made by the client during the project. Something on the model needs to be fixed because new information is replacing the original data. This might mean a return to the 3D drawing stage to redesign a part, or simply the integration of a new file sent by the client.

Other times, inconsistencies in materials can make for mistakes in the modeling process. Model makers are prepared for the occasional odd performance of resin, plastic or paint.

More commonly there will be a mistake in fabrication. A model maker spends a good deal of time on the actual build – molding, sawing, drilling, routing, welding, cutting, gluing, painting, sanding or milling. Even the most experienced model maker will occasionally mess up during one of these processes.

Fixing mistakes and making adjustments are part of the model making routine, and generally do not get in the way of a project’s successful completion. Model makers put a lot of effort in the planning stages to avoid costly mistakes later on. However, being  gifted with their hands, as well as analytic thinkers, they are well prepared for the challenge of when things do go wrong.