The next big thing in CAD, CAM and CAE is upon us. 3D solid model files are a great tool for the visualization of what a part will actually look like. I have heard from designers that rendering a part in 3D is less time consuming than its 2D sibling. But what are the advantages of each?

 3D Solid Model

 

1. Extraction of dimensions
2. True visualization
3. Easy calculation of weight and surface area, this is helpful in getting a good handle on the cost of things; freight, part handling, metal finishing, precious metal plating, painting, calculating of scrap, versus weight of part.
4. Ability to run part through CAM software like MasterCAM or FeatureCAM. This makes writing a program for a CNC machine a more exact task. It also saves times and cost in writing these “G” code programs.

 2D Drawing

 

• Dimensional tolerances
• Exact dimension and any special tolerance callouts
• Specified materials
• Metal finishing
• Surface finish (RMS)
• Heat treatment
• Concentricity
• Total Indicator Runout
• Part marking method (if any)
• Bill of Materials (if any)
• Different variations on the design of the part (exp. -1 is .020:” -2 is .025” et al)
• Specification of critical features in both dimension and design
• Proprietary information, and revision level

 

 As you can see, 2D, while not as exciting as 3D, gives a manufacturer far more information necessary to produce a component part than 3D can. The deficiency of 3D is the inability to imbed all of the information that is common place in 2D drawing files.

 As a parts manufacturer, we always prefer a 2D drawing. But designers who are providing both 3D and 2D seem to have all the bases covered. We speculate that in just a few years’ time, it will become expected that an RFQ will be accompanied by both 2D and 3D part files. For many of Luso Machine customers, we are already benefiting from that trend.

As manufacturers we send out quotations  to our customers many times each day. We also send out RFQ’s for materials, and services many times each day, as well.

 

As a CNC machining and contract manufacturing company, the most frequent RFQ sent out each day, is for metal materials. We try to get as many quotations as is possible for the required material, for a RFQ we receive from our customers/prospects.

Many times we see quoted prices for the same commodity, that are worlds apart! Human nature being what it is, is to go with the lowest quoted price. But when one supplier quotes $243.00 (51.92% of the competitive cost) for 27 pieces of 4.25″ diameter x .625″ thick, of 304L Stainless Steel, and another supplier quotes $468.18 (1.92 times the cost), you scratch your head and wonder whose price is the right one.

I know that its easy to convert everything to a pound price and see whose may have made an error. We are always tempted to call each supplier and tell them what their competitions price is, and see if an error was made. Many times the reply we get is that; the lower price supplier does not know what they are doing, and the higher price supplier either does very little business in that commodity or just does not have a handle on the market and it’s competition.

In any event,  as a company who depends upon these quotations to formulate our cost to our customer, we worry that by going with the lower cost supplier’s price, we will hear from that supplier, when it is time to order the material at the lower cost, that they made an error, and can not honor their lower prices.

To say the least, every quote that is made from such wide ranging prices of the same commodity, is a bit anxiety provoking. But fortunately when the low cost supplier realizes his error, most of the time they honor their quoted price, and learn the valuable lesson. It’s like carpentry, measure twice, cut once.