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CAD Tips

For those who are in the design departments this section contains a few tips on improving graphical communication. Our main concern is that a drawing contains all of the necessary information to construct the part. Clear and accurate drawings help ensure that each customer gets the product they are expecting. An analysis of previous nonconformance, reworks and rejects has shown that a significant source of errors is due to poor or incomplete drawings. A poor drawing can take as much as five times longer to process than a good drawing.To get more news about cad tips and tricks, you can visit shine news official website.

Due to the number of people and steps involved in the manufacturing process, the drawing should stand on its own and not require verbal ancillary information. Hansen Industries can provide a service to bring drawings to standard or refer the customer to a third party CAD provider. The manufacturing time and part quality can be improved further if the drawing is transmitted electronically or provided on diskette.
This section describes a set of drawing standards, which, if followed, will improve the chances of receiving a part that could be used in production on the first run.

All drawings should be 3rd angle projection, according to North American standard. If a drawing is in 1st angle projection (usually from European customers) it should be noted on the drawing. With most parts a minimum of three views should be given (i.e. top, front, side).
An isometric view with hidden lines removed will aid in the visualization of complex parts. Provide a general assembly drawing for multi-part assemblies.When dimensioning parts, please adhere to these guidelines:
For CAD drawings, always draw full scale with true size for holes, cutouts, special shaped holes (i.e. single and double 'D') and DB cutouts.

Use ordinate dimensioning with a common datum between views.
Dimension all hole diameters, including PEM fastener holes. Use hole charts to reduce clutter.
Fully specify all hardware (i.e. f0.137 +0.003"/-0.000" for FH-632-8 4 PLCS THIS SIDE). Show direction of projection in other views.
Dimension radii of all rounded corners and cutouts.
Use text heights of no less than 0.090".
Provide additional views to avoid over-crowding.
Dimension corner notching clearances.
For a grid pattern of holes, provide row and column spacing rather than dimensioning every hole.
Please do not dimension off of center lines unless symmetry is indicated.
For counter sunk holes, dimension the ID and OD as well as the depth of the countersink required and specifies the screw (imperial or metric) that the countersink is intended for as well.
Indicate critical dimensions on the drawing for inspection purposes.
Although we are a precision sheet metal shop, try to relax tolerances as much as possible. An industry adage is "adding a zero to tolerance adds a zero to the price".
Welding details specifying weld location and type of weld should be given.
Clearly indicate whether flange dimensions are inside or outside. Outside dimensions are preferred.
Dimensions should not converge to a non-measurable point