Architecture model materials: which sheet, and when

Chipboard is compressed recycled paper, sold in 1-, 2- and 4-ply. It is cheap and easy to cut, which is why it fills study models and bases. Thick stock takes repeated passes with a knife and leaves a rougher edge, and broad panels can warp with moisture or glue.

Many labs accept it on the laser, though the edge chars. Harvard GSD’s fab lab lists chipboard as approved (opens in a new tab). More in chipboard compared.

Museum board is a dense, smooth paperboard, usually archival. It gives clean presentation walls and precise flat parts. It can bow when damp, and it is weak for slender structure. On a laser it can scorch and darken at the edge.

More in museum board compared.

Basswood is a fine-grained, light wood, sold from 1/32" to 1/4". It is stiff, so it suits frames and ribs. The grain can pull a knife and split a thin part, and flatness varies from sheet to sheet. The USF XARTS material guide (opens in a new tab) says it can be laser cut.

More in basswood compared.

Foam core is polystyrene foam between two paper faces. It is light and fast, so it suits large massing models. The University of Melbourne’s model-making guide says to cut it gradually, in a number of consecutive cuts (opens in a new tab), so the inner foam does not tear. A dull blade crushes it, the edge is hard to finish, and the board dents and bows.

Many labs ban it on the laser because the foam is polystyrene, among them Harvard GSD (opens in a new tab) and Syracuse (opens in a new tab). More in foam core compared.

Cork gives a natural texture, which suits terrain and landscape. Acrylic is rigid and heavy, and it is the usual sheet for glazing. It gives a clean edge on a CO2 laser, it is flammable, and clear acrylic does not cut on a diode laser. Illinois’s DigiFab shop (opens in a new tab) lists cork, acrylic, basswood, chipboard and museum board among its approved laser materials.

MDF is wood fiber bound with resin. It is dense and uniform, and it suits routed terrain, but it is heavy. On a laser it smokes and chars, and its binders are why many labs restrict it. Harvard GSD’s fab lab lists MDF as a material not to cut (opens in a new tab). Penn Design’s fab lab allows it at 1/8" only (opens in a new tab).

Taskboard® is a white fiber board. It is about half as dense as museum board or chipboard, so it cuts more easily by blade and faster on the laser, and it costs about half as much as museum board. It stays flat and has no grain, so it cuts the same in every direction. On a laser it cuts faster, with a light brown edge that sands clean.

The USF XARTS guide says it does what chipboard does and is easier to cut. The sheet comes in 1/32", 1/16" and 1/8". For how to pick a thickness by scale, see site models.

First, read your lab’s laser list. It decides what you can cut on the machine, and it varies: Harvard GSD, Penn Design and Syracuse each publish their own.

Second, name the job. Fast volumes call for foam core or chipboard. A clean presentation wall calls for museum board or a white board. A frame or rib calls for basswood. Glass calls for acrylic. Ground calls for cork, or layers of any flat sheet.

Third, look at the edge. If the model will be seen up close, a sheet that cuts clean and sands clean saves finishing time. Fourth, buy a small amount and test cut before you commit to a stack of sheets.

Buying a sheet your lab bans on the laser. Foam core and MDF are the usual ones.

Choosing thick chipboard, then fighting it with repeated knife passes. Gluing broad paper panels with too much glue, so they warp. Using a dull blade. Skipping the test cut. And mixing too many materials: two or three are plenty for most models.

For the tools, see model making supplies. For ground, see site models. For laser rules, see laser cutting materials.