Profile drawing and tolerance
The rollers are designed from your drawing. Agree dimensions and tolerances in writing, and ask for the flower pattern showing each forming step.
No DramaBuyer guide · Metal & CNC
A roll forming machine is built for one profile, so the drawing, the material and the rollers matter more than the machine around them, and a mistake in the drawing is paid for in new rollers.

01
The rollers are designed from your drawing. Agree dimensions and tolerances in writing, and ask for the flower pattern showing each forming step.
Number of forming stations and shaft diameter decide how gently the strip is formed and how thick it can be.
Ask the roller steel, heat treatment and chrome plating, and whether drive is by chain or gearbox.
A stop-and-cut shear is cheaper; a flying cut keeps the line moving. Punching holes in line is another option priced separately.
Purlin lines may change size automatically; others need roller changes. Ask how long a change takes.
02
Send these with the enquiry. Without them, any number a factory gives you is a guess dressed as a quotation.
03
| Require this | A pass looks like |
|---|---|
| Run your coil after a warm-up and measure the profile at several points along the length. | Profile inside drawing tolerance, with no flare at the ends and no twist or bow over your limit. |
| Cut twenty parts at production speed. | Cut lengths inside your tolerance and no burr over your limit. |
| On coated coil, inspect the surface of formed parts. | No scratches or cracked coating on visible faces. |
04
05
A CNC press brake, which changes shape with a new program.
Prototype on a press brake until the drawing is fixed.
06
We name the kind of source, how many and when, and never the factory. Listed prices are asking prices, not landed cost. Where we do not hold a fact we say so: that is a GAP, not an estimate.
07
Every machine we source in this area is on the Metal & CNC page. How a project runs, stage by stage, is on how it works, and what it costs is on pricing.
Straight answers
Roller design skill is the gap. Test on your coil and your profile.
The three tests above, station count, and roller hardness against the offer.
A Declaration of Conformity covering the line with decoiler and cutter, a technical file, and a manual in your language.
If you import it yourself, you are: check the documents and put your name and address on it.
Contact
Send a machine, a quotation you want checked, or a question. We reply with what we would look at first.
Sent
A person reads every message. You will hear back within one working day.
Not sent
Please email info@nodramachina.com directly and we will pick it up from there.