How soon can you get my project done?

Lead times are heavily dependent on project scope. Fill out a Request for Quotation complete with your desired time frame and we’ll get back to you to work out details.

What are your rates?

Our rates vary based on the type of work and activities performed. Send us a Request for Quotation and we’ll put together an estimate.

Is STEL hiring?

Check our Careers page for current job opportunities.

Estimates & Proposals

What is the quoting process and how can I get an estimate?

Quoting couldn’t get any easier. Just fill out a Request for Quotation and we’ll get back to you with an estimate. If you like what you see, we’ll draft up a proposal and can start work as soon as it’s signed!

What are your payment terms?

All invoices are net 15. STEL generally requires a 50% down-payment upon signing of the proposal. The balance is payable upon delivery of the product.

What forms of payment do you accept?

STEL accepts cash, check, money orders, and these online payment forms: Accepted eCommerce Logos

3D Prototyping / STEL3D

What kind of prototyping does STEL3D provide?

STEL3D provides the following prototyping solutions:


  • Additive Manufacturing (PolyJet, SLA, FDM)
  • Subtractive Manufacturing (CNC milling & turning)
  • Injection & Pour Molding (low volume)


Using these methods, STEL/SB3D can prototype products out of a wide variety of plastics, epoxies, rubbers, and metals.

Why should I choose STEL3D for my prototyping needs?

  1. Quick turnaround
  2. Low overhead
  3. Proven track record


In addition to supporting your prototyping needs, STEL/SB3D is able to provide design support to lower unit cost and ensure scalable manufacturing capabilities.

What capabilities can you achieve with each process?

Build Volume (xyz) Tolerance Materials
CNC Any 0.005” std, 0.002” possible Most metals, plastics, wood
Low-volume injection molding Any 0.005” std, 0.002” possible Thermoplastics, TPE, TPU, silicones
Low-volume pour molding Any 0.005” std, 0.002” capabilities Elastomeric materials (TPE & silicones)
Polyjet (3D Printing) 294 x 192 x 14.6 mm (11.57 x 7.55 x 5.85 in) 0.0039” Rigid, transparent, PP, high-temp
SLA (3D Printing) 635 x 635 x 533.4 mm (25 x 25 x 21 in) 0.005” std, 0.002” possible ABS, PC, PE, PP high-temp
FDM (3D Printing) 203 x 203 x 152 mm (8 x 8 x 6 in) 0.007” ABS (multiple colors)

How can I place an order?

To get your project(s) made, please fill out the Quote Form at We’ll get right back to you with an estimate and will start prototyping once it’s approved!

What requirements are there to process my CAD model?

In order for STEL/SB3D to process your model, please send your 3D file in one of the following formats:


  • .STL
  • .X_T
  • .IGES
  • .STEP

I don’t have an appropriate CAD model. Can you convert/make one for me?

No problem! Just provide us with the necessary dimensions and details so we can accurately model your project.

What is additive manufacturing and when should I choose it?

Additive manufacturing (AM) builds your part from the ground up, layer by layer. Using this method of manufacture, material is deposited or fused little by little until the final part is completed.

3D printing is a type of additive manufacturing technique that is best suited for prototyping and low-volume production.

What is subtractive manufacturing and when should I choose it?

Subtractive manufacturing uses conventional metal cutting machines like mills and lathes to remove material from a single block of “stock” until your part is created.

Subtractive manufacturing is the preferred manufacturing technique for parts that will experience high loading. This method is ideal for mid- to high-level production.

What is injection molding and when should I choose it?

Injection molding creates a part by forcefully inserting molten plastic into a negative form — the mold. Once the plastic solidifies, the mold is removed to reveal the finished product.

Because relatively expensive tooling is required for injection molding, the process is most efficient for high-volume production. However, lower-volume applications can be justified for certain materials.

What is FDM?

“Fused deposition modeling” (FDM) is an additive manufacturing process whereby thermoplastic material is extruded through a heated extrusion nozzle — similar to a glue gun — depositing quick-solidifying molten material onto a surface in successive layers.

What is PolyJet?

PolyJet (PJET) printing is an additive manufacturing process similar to traditional toner-on-paper printing. Layer by layer, thermoplastic or wax material is “jetted” onto a surface, where it is then cured. The resulting part can be quite complex while maintaining very good surface finish.

What is SLA?

“Stereolithography” (SL or SLA) is an additive manufacturing process in which parts are created from a curable photopolymer. Layer by layer, a laser precisely solidifies resin until the final shape is created.

Industrial Design

What is industrial design?

Industrial design gives character to a product. It’s the process of refining shapes, materials, and finishes to give an item life. The real challenge is giving a product a premium form and feel while maintaining the underlying functionality. Sound industrial design yields something you can’t help but pick up and touch — something you feel excited to look at and hold on to. Sound industrial design yields something you just have to have.

Can you assist me with material selection and finish?

Absolutely. Materials and finishes are an essential part of the user experience; we’d be happy to help you choose the right ones for your product.

What is CMFG?

Color / Material / Finish / Graphics. CMFG is the selection of appropriate colors, materials, finishes, and graphics that are applied to create an aesthetically pleasing and emotionally connective product.


What is “geometric fitting”?

Geometric fitting is the initial placement of internal components in 3D space. A primary feasibility consideration, geometric fitting is necessary to ensure a design can fit within a defined envelope.

What does “detail design” entail?

Detail design is where all the nitty-gritty engineering occurs. From the full definition of parts in CAD software to tolerancing, alignment, and finite element analyses, detail design is where a majority of design effort is spent. Materials selection, DFM, and the generation of engineering documentation for subsequent product manufacture is also included in this step.

What are tolerance stackup analyses and critical fit reviews and why are they important?

In theory, it should be easy to design an assembly that goes together without a hitch — just mock it up on a computer and order the parts, right?


Unfortunately, it’s not that simple. The parts you design on the computer aren’t necessarily the parts you’ll get in person. What’s more, you can make two engineering drawings of the same part and get significantly different results from the same shop!


Inherent to every fabrication process is a “tolerance”, an acceptable deviation from a nominally defined value. No process is exact, and the more precise you go, the more expensive things get. In order to keep costs low and still make sure parts always fit together, tolerance stackups and fit reviews are a necessary step in the design process.


Here’s an example. We have a simple rectangular bar with a hole in the middle. Below, we have that part drawn twice; the differences are shown in red.

So we have the same part, just drawn a little differently. I should be able to send out either drawing to a machine shop and get a 2″ x 1″ bar with an 1/8″ hole in the middle, right?


Well, not necessarily. Most drawings have a drawing block that define “standard tolerances”.

That means that in the drawings above, each two-place dimension has a tolerance of ±.01″, and each three-place dimension has a tolerance of ±.005″.


Thus, we can technically receive the any of the parts below and anything in between — all are “to print” and were manufactured correctly, but they definitely aren’t the same.

What if that 1/8″ hole was meant for a dowel pin? If it were drilled out with a #30 drill (Ø .129), it would still be “to print”, but the pin would slip right through. What if that dowel pin was supposed to press into another part beneath this bar? If the fit was critical, it might not line up.


One can imagine how crucial it is to take these real-world limitations into consideration when creating complex assemblies with many parts. Without tolerance stackup analyses and critical fit reviews, clearance issues and interferences are bound to happen.

What is an “interference”?

An interference occurs when two or more bodies try to occupy the same volume in 3D space. Interferences usually occur when adequate clearances are not maintained and proper tolerance stackups are not performed. We make sure to run interference diagnostic tools on every design to prevent these issues from arising during production.

What is FEA?

“Finite element analysis” (FEA) is a computational technique enabling engineering analyses in simulated environments. The practical application of the finite element method, FEA can be used to analyze stresses and strains under internal and external loading.


In simple terms, we use FEA as a tool to help us choose materials and optimize shapes to reduce cost and increase performance. Taking into account forces, pressures, accelerations, and temperatures, we can evaluate and improve assemblies before a single part is made.


Want to know if a part will break if you drop it off a three-story building? Curious to see if an assembly will bend if you stand on it? Need to know if a design will hold up to vibration, underwater depths, or extreme heat? With FEA, we can give you all those answers before you get something made. Saving you time and money, FEA makes trial-and-error and oversimplified analyses obsolete.

What is DFM?

“Design for manufacturing” (DFM) is the process of tailoring components to minimize fabrication costs and maximize ease-of-assembly. The first step is ensuring that a component can be made using the selected manufacturing method. The next step is addressing concerns that are manufacturing technique dependent; stock sizes and feature shapes/dimensions are important considerations for CNC work, for example, while component size and fill density are important considerations for 3D printing.


Whether it’s minimizing cycle times and tooling costs or maximizing yields and material efficiency, DFM is necessary to reduce time and cost per unit, regardless of manufacturing method.

Why is a mold flow analysis necessary?

A mold flow analysis is an essential part of the DFM process for injection molding. In order to reduce tooling and production costs, a mold flow analysis takes into account the material and form of the final product to determine the ideal single or multi-cavity tooling setup. Everything from the size and location of sprues, runners, and gates to the pressure of the flow and the rate of cooling are considered to minimize cycle time and cost. Care at this stage is critical to saving money on every unit produced.

Can you provide material suggestions for my design?

Absolutely! STEL employs materials engineers who specialize in material selection. Be it billet CNC work, sheet metal bending, injection molding, or additive methods, STEL can help you find the right material for every application and manufacturing process.

Can’t find your question here?

Send us an email.