By: Randy Amundsen Date: August 20, 1998
We probably have 20 calls a week from customers who are full of ideas and thoughts about designing or re-designing our products or someone else's product. Some have a brand new idea that they would like us to manufacture. We like to hear new ideas and sometimes we can react and sometimes not. Bringing a new idea to market is a very complex task and very time consuming.
Several months ago we received our first BlockZilla blocks and right away we saw the need for a better side cover and a market for it.
What do you do, you have no drawings, all you have is a shape.
The first thing we did was to mount the block on a rotary fixture in one of our Haas Machining Centers in a horizontal position with the crankcase opening up. The block had to be perfectly square with the table. Now we are not talking just close, but within tenths of thousandths.
Now the block can be digitized. This is a process of converting shape into numbers.
Using the crankshaft center line as the starting reference, the crankshaft bearing pocket, the camshaft bore, bolt holes and dowel pin holes are located. Now the inside of the casting, as well as the outside, must be traced taking readings every .100" in the straight areas and sometimes every .020" in the curvature areas. We now have pages of reference point measurements. This process takes about 6 hours.
These numbers are now transferred to a CAD system and a simple drawing is now created. From this, we now make a template side cover to test all the measurements. This is checked and rechecked for accuracy and how it fits the block. The crankshaft and camshaft must be installed and checked.
The process has been simple so far and now the time consuming work begins.
Designing is a true art form that takes a lot of talent, imagination and patience.
You must have a superb knowledge of what this part plays in the function of the engine. Are there improvements to be made over the original and other designs ? If so, will the improvements make the part better ? We ask for input from engine builders and our racing customers. Many hours are spent in round table discussions.
You first must address the structural integrity of the part. Where does it need to be strong and where can you remove metal to make it light ? After all of this is done, then you design in the cosmetic enhancements.
While you are working your way through this process, you are also selecting the tooling such as end mills, drills, taps etc., that you will need to do the different holes, cuts, pockets and contours. Your goal is minimum tool changes because this is time consuming in a production environment. This will cause you to re-think some of the shapes and modify the program.
This is a very time consuming process and one is sometimes tempted to cut the cosmetics a little short. If you have ever seen anything we produce, you know we don't cut anything short.
Holding fixtures are the next most important project. There is an old saying in this industry, "If You Can Hold It - You Can Make It". To hold a part in one position and finish the product is simple. To hold a part multiple times, in different positions, is another art form in itself. When a part is moved to a different fixture, it must be precise and sometimes the accuracy must be held in the tenths of thousandths.
Now the holding fixtures must not only be accurate, they must be durable enough to withstand production. Are we going to make 100, 1,000 or 10,000 or more of these parts ?
We are now ready to make our first part. This is done slowly so that each part of the program can be checked. Like it or not, there are errors and adjustments are made as we go.
We now have our first side cover and it must be evaluated on a test motor. After very extensive testing, we are now satisfied with the product.
We now enter the final stage of cosmetic programming. This is where spindle speeds and feed rates are adjusted and different tooling is experimented with.
The finished product must be free of tool marks and should have a polished look right out of the machining center.
Overall time for this project was about 1 month with at least 100 hours spent on computer design, programming and machine time. Hope you like the product.
Thursday, August 20, 1998
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