Sheet metal fabrication turns flat stock into finished parts and assemblies without any part specific tooling, which makes it unusually flexible: the same shop and the same process can make one bracket or ten thousand. Understanding the four stages a part passes through is what lets a buyer see where a design decision will land in the price.
The four stages
Cutting produces the flat blank, usually by laser, sometimes by punching or waterjet. Forming folds or draws it into shape, almost always on a press brake. Joining attaches it to whatever it must be attached to, by welding, riveting or pressed in hardware. Finishing deburrs, coats or plates it. Every quote is those four stages plus material and handling.
Techniques a fabricator has on hand
Laser and punch cutting, press braking, roll forming, deep drawing on the shops that have presses, TIG and MIG welding, spot welding, self clinching hardware insertion, tapping, countersinking, tumbling and deburring, and usually a relationship with a plater and a powder coater. What a shop does in house rather than subcontracts is the single most useful thing to know about it.
Choosing between suppliers
Ask what is in house and what goes out, because every subcontracted stage adds days. Ask what thicknesses and what brake tonnage they run. Ask whether they will review the part before cutting it, since a bend sequence problem found then costs nothing. And ask about welded assemblies specifically, because fixtures are the hidden cost in fabricated work.
What to send
The folded three dimensional model, a drawing marking critical dimensions and finishes, the material and thickness, the quantity now and later, hardware part numbers, and the finish specification with masking noted. Let the fabricator generate the flat pattern with their own bend allowances rather than supplying one from elsewhere.
Questions people ask about sheet metal fabrication suppliers
What is sheet metal fabrication?
Turning flat sheet into finished parts and assemblies by cutting, forming, joining and finishing, without part specific tooling.
How do I choose a fabricator?
By what they do in house, their thickness and brake capacity, whether they review parts before cutting, and how they handle welded assemblies and fixtures.
Does fabrication scale to production?
Yes, better than most people expect. Many products never move to stamping because laser and brake fabrication remains competitive at surprisingly high volumes.
What is the most common cost surprise?
Welding fixtures on assemblies, and multiple finishes or thicknesses in one part, each of which adds a setup that is invisible on the drawing.