Do you have a project in mind but not sure what tolerances to use? Don’t worry we got you covered. Here’s a overview that you can use to build your product.
In the absence of the client providing a drawing with agreed upon tolerances, the part(s) shall be manufactured as the per client’s supplied CAD model, with the following Tripar default manufacturing tolerances:
The sketch above is for illustrative purposes only.
Table 1. Default Tolerances
|DIM||Tolerance (“ ±)||Description|
|±0.010”||Holes1 & linear dimensions of flat pieces < 0.5”|
|±0.015||Holes1 & linear dimensions of flat pieces 0.5”< 4.0”|
|±0.020||Holes1 & linear dimensions of flat pieces 4.0” < 12.0”|
|Upon Review||Holes1 & linear dimensions of flat pieces > 12.0”|
|A||±0.010||End to hole or bend|
|B||±0.010||Hole center-to-center (on one surface/plane)|
|C||±0.015||Bent edge to hole2|
|D||±0.020||Distance over 2 bends2|
|E||Undefined (TBD)||Distance over 3 or more bends2|
|R||1-2X Material thickness||Inside bend radii|
1 If the hole is not round, the above ranges apply to the largest dimension in the opening.
2 As measured nearest to bend(s).
3 Thin metals have some flexibility, and thus can deflect, even under their own weight. As such, tolerance applies up to 1” from the bend. For reference; 2° over 1” = .034”.
For those who provide, or are considering providing their own tolerance drawings, please see the following two TriparTech article on this subject, as well a sound sheet metal design practices;
Surface Finish: Shall be in accordance with material specified and associated governing specifications.
Formed or bent parts may have small surface blemishes near the areas of transition.
Residue: Metal fabricated parts are often produced and may be shipped with lubricants or dry film lubricants.
Protective Film: For raw materials which come with a protective film, parts shall be provided with this film, to help protect the parts until you, the customer remove when desired.
Small burrs are an inherent part of metal stamping & fabrication processes. Being nearly impossible to quantify & measure, unless otherwise specified parts are provided in their “as stamped” or “as fabricated” condition.