Answers to Frequently Asked Questions on 3D Printing

SLA

What does SLA mean?

SLA is short for Stereolithography and it is one of several additive manufacturing, or 3D printing, processes. An SLA machine uses a laser to cure molten resin into a solid part, one layer at a time. The molten resin comes in a large vat with a honeycomb-like tray upon which the part is cured. As the laser cures each layer of resin, the tray moves down into the vat to get a fresh layer of resin for curing. At the end of the build cycle, the tray comes back up out of the liquid and reveals your completed part.

What can an SLA model be used for?

SLA models are perfect for use as sales samples, trade show displays, and custom display pieces. The surface is easy to work with, which makes them ideal for various finishing processes. Once finished, your model will look and feel like your final, post-production, finished product.

Although SLAs are not quite as strong as FDMs, they can still be a good option for form and function testing in certain situations. The clear SLAs may yellow a bit over time, but the industry is working to correct that.

What are your size constraints for SLA models?

Our SLA build tray is 13.75” x 13.75” x 15.75”, but if your part is larger than that, we can usually print it in pieces and assemble it together using various techniques.

How do you determine the price of an SLA model?

The most important factors in determining price are the volume of the part (how much material is needed) and build time (how long it will take the printer to build the part). The Z height of your part makes the biggest difference in build time. Finishing processes also contribute to the cost.

What finishing options are available on an SLA?

SLAs can be ordered with the following finishes:

  • Standard – remove supports, sand to 220, bead blast
  • Mold Ready – remove supports, sand to 320, remove exterior build lines (smooth surface)
  • Painted – remove supports, sand to 320, remove exterior build lines, paint in any color (color matching available)
  • Engineering Clear – remove supports, sand to 320, remove exterior build lines, apply clear coat
  • Aesthetic Clear – remove supports, sand to 600, remove exterior build lines, seal with clear coat
What materials can you print using SLA?

Our SLA prints with a synthetic plastic resin. We currently carry Accura Xtreme White and Accura Clearvue, which is translucent. We also offer Somos Perform, which has a high heat tolerance and low viscosity, making it perfect for making temporary injection mold tooling.

What do you mean by "support material"?

When you are 3D printing a part, the liquid material always needs to land on some sort of surface–it is not possible for the material to be suspended in mid-air (not yet anyway). The SLA builds a very thin support structure, similar to scaffolding, which is easily broken away after the part is finished.

Do I need a CAD file to order an SLA model?

Yes. The SLA uses a CAD-generated STL file to determine the data for each layer of the model. Broadview can convert files from most any CAD platform free of charge. If needed, our engineers can turn your 2D sketch into a full 3D CAD model, or repair your CAD file (for an additional fee).

What colors can you print using SLA?

We can print in grey or translucent.

What tolerances can your SLA print to?

Accuracy can sometimes depend on your part’s geometry, but usually we can meet an accuracy of +/- .005 inches or +/- .0015 inch per inch, whichever is greater.

What is your typical lead time for an SLA model?

As a “rapid” prototyping shop, our goal is to have your part ready in less than 3 business days. If you need it in less than 3 business days, we can usually accommodate you. We will always specify a delivery date when we quote your project, and inform you immediately if we run into issues.

FDM

What does FDM mean?

FDM stands for Fused Deposition Modeling and it is another type of additive manufacturing, or 3D printing, process. An FDM machine works sort of like a CNC machine, but picture a hot-melt glue gun instead of an end mill. In other words, it dispenses melted material which immediately hardens, or cures, upon contact with the build tray. The FDM builds parts in layers, starting with the base layer and adding material until the part is complete.

What can an FDM model be used for?

FDM models are great for engineering testing and checking the functionality of your part. The material used in an FDM machine can match that of your final product, i.e., ABS, polycarbonate, and nylon. For a more “polished” looking prototype to be used for sales presentations and the like, an SLA would be better. Learn more about SLAs.

What are your size constraints for FDM models?

The size of the build platform on our FDM machine is 14″x 16″x 16″, but if your part is larger than that, we can usually print it in pieces and weld the pieces together depending on your goals for the prototype.

How do you determine the price of an FDM model?

The most important factors in determining price are the volume of the part (how much material is needed) and build time (how long it will take the printer to build the part).

Do I need a CAD file to order an FDM model?

Yes. The FDM uses a CAD-generated STL file to determine the data for each layer of the model. Broadview can convert files from most any CAD platform free of charge. If needed, our engineers can repair your file or turn your 2D sketch into a full 3D CAD model (for an additional fee).

What materials can you print using FDM?

Our FDM machine can print parts in ABS M30, ABSi, ABS M30i, ABS ESD7, ASApolycarbonatePC-ABS, PC-ISO, PPSF, Nylon 12, and ULTEM 9085. Each material serves a different purpose. For material specifications, please click on the material name. If you need help deciding which will work best for your project, please get in touch and we’ll be happy to help!

What colors can you print using FDM?

Our standard colors are black for ABS M30 and Nylon 12, or white for Polycarbonate. We can source different colors in ABS, but it would likely increase your lead time by a few days–options are: natural, white, dark grey, red, and blue.

What tolerances can your FDM print to?

Accuracy can sometimes depend on your part’s geometry, but usually we can meet an accuracy of +/- .005 inches or +/- .0015 inch per inch, whichever is greater.

What finishing options are available for an FDM?

All FDMs are finished the same way. We simply remove any support materials and pack it up for shipping. For a more polished look, read about our SLAs.

What do you mean by "support material"?

When you are 3D printing a part, the liquid material always needs to land on some sort of surface–it is not possible for the material to be suspended in mid-air (not yet anyway). The FDM builds a support structure in those empty spaces using a different material which gets dissolved in a solution after the part comes off the machine.

What is your typical lead time for an FDM model?

As a “rapid” prototyping shop, our goal is to have your part ready in less than 3 business days. If you need it in less than 3 business days, we can usually accommodate you. We will always specify a delivery date when we quote your project, and inform you immediately if we run into issues.