Mechanical design: Rants and pet peeves

March 2nd, 2010

Welding is but a part of the trade’s work. At times it is of the utmost importance for the weldor* (WeldOR = person vs WeldER=machine) to know how to re-enforce or enhance the repaired weld joint or member to achieve a long-lasting repair. Design is critical to nearly every mechanical and structural part/frame/machine etc. Nearly every manufactured item is built as economically (CHEAP) as possible to keep costs to a minimum. Some manufacturers employ real honest-to-goodness licensed engineers, but not all. Some folk have a very strange sense of mechanical theory so it’s often amusing to see what some repairs become when done by a person with this trait.

One of my pet peeves is the 45 degree gusset and it’s over-use by some weldors who have no confidence either in their design abilities or their weld quality. It sometimes looks as though they think with less than 5 or 6 of these gussets, it’s going to break in a millisecond. I prefer to use members for projects that are suitably strong to do the job just right. It’s a rare occurrence when one of my projects sports a gusset and when it does happen, it’s very reasonably the ONLY possible solution for it’s location.

Occasionally welds are extremely inadequate for a manufactured item. Often I’ve come across parts with barely the slightest wisp of a weld bead making me wonder if the weldor forgot to final-weld a tack. This is NOT the case after I’ve repaired a part.

Recently, a friend’s relative came by with a hitch installed on a new truck. The welder used a piece of 1/4″ x 2 flat bar bent with a 4″ Radius, curved 90 degree bends (bent the easy way, with an S-shape) and used this to support the receiver tube under a flimsy stamped-steel bumper!! No torsion tube across the chassis rails. No, but that installer added 2 pieces of 1″ dia pipe welded at a diagonal angle to keep the forward end of the receiver tube from side-to-side movement. It’s sad, because he was charged (robbed) of $350.00 for this lousy set-up and there’s no regulatory agency covering hitches.

True, any yahoo can put up a sign showing: “Welding” then take your money with nary a second thought about it. NOT a governmental or political remedy needed here. However, I’d support an INDUSTRY-WIDE effort to create a ‘right-of-passage’ for all would-be and wannabe Weldors, Weldor-Fabricators to pass a standardized application and test to certify not only their welding ability but some elemental design criteria and layout/blue-print reading.
(Surely, I do mean CAD Drawings as well).

Since that time I’ve replaced his entire hitch with one that will pick up the back of his truck if lifted at the hitch. I had to demonstrate this with one of my customers one time. By inserting a solid 2″ square steel bar x 3 ft long into the hitch receiver, I used my forklift and picked up his pickup truck, with both back wheels OFF the ground. Only then, was he convinced I knew my job.

Greetings to All Fellow Fusion Artists and Trades Folk.

March 1st, 2010

Had to begin somewhere, and this is it. What’s on YOUR mind today? Questions regarding the fine Art & Science of Metal Fusion? A particular project giving you fits?

Having been blessed with a great choice in careers employing my God-given talents in the field of Welding, Metalwork, and Mechanical design (Seat-of-pants variety) I really cannot imagine how I’d ever be satisfied working at any other trade or career. Having been at this trade continuously for 40+years, I can offer my meager lessons learned and weld-shop mentoring to those who may have a question or two related to this field. Someday this information may need to be sold, but today it’s free.

Let me know what’s going on in your realm.