You can email your questions to Professor Hammer at covell@cruzio.com, or mail to Professor Hammer, c/o CLASSIC TRUCKS Magazine, 774 S. Placentia Ave., Placentia, CA 92870-you'll receive a personal reply! We'll print your name and city unless you request otherwise. Ron Covell has made many DVDs on metalworking processes, and he offers an ongoing series of workshops across the nation covering all aspects of metalworking. Check them out online at www.covell.biz, or call for a current schedule of workshops and their free catalog of DVDs. Phone 800-747-4631, or 831-768-0705. You can send a request by mail to: Covell Creative Metalworking, 106 Airport Blvd. #105, Freedom, CA 95019.
Dear readers,
It's time for a little celebration! This marks the 10-year anniversary for the Professor Hammer column in CLASSIC TRUCKS magazine! Over this time I've had the pleasure to offer advice and encouragement to well over 200 builders, both amateur and professional, and it pleases me very much that I have been able to share my knowledge with these people. I'm really looking forward to the next 10 years!
Q. Hi Ron, I want to thank you for all you do to support and promote the metalworking community. Earlier this year my wife decided to get me the Scratch-Building a Fender DVD-it was a great present!
I'm working on a '51 F-1 frame and hope I can get your thoughts on the modifications. I've included some pictures to help with my explanation. I think this modification is called a Z, but it's not as radical as many I've seen in the magazines and on the web.
Basically, I want to cut the frame behind the cab and raise the rear about half the height of the frame, then fill in the open spaces with some small triangular pieces, and add a sister plate on the inside of the frame. I also plan to box the frame and add some sort of crossmember.
The frame is the typical C shape, and has been sandblasted and squared up. I welded some temporary crossmembers to the frame to keep it square after I cut it. I have a home-made frame table to work on. I tinted the different frame sections in the pictures to show the locations of the welded joints. I plan to cut the frame perpendicular to the length of the frame, and cut the small triangular sections from a spare frame. I'll make sure I clean and properly fit the areas to be butt-welded, and I plan to V the frame before I make the welds.
I plan to cut a sister plate from metal the same thickness as the frame, and weld it inside the frame channel. I plan to drill some holes in either the frame or sister plate, so I can plug-weld them, and stitch weld around the edge of the sister plate. When I box the frame I plan to recess the boxing plates into the channel of the framerail around 1/4 inch, so I can join them with a fillet weld.
So I have a few questions: Does this sound like a reasonable approach to modify my frame? Is a single V groove enough on the butt-welds? Is it better to drill the frame, or the sister plate for making the plug-welds? Do you have any other comments, concerns, or suggestions?
Phil Mackowiak
Via the Internet
A. Glad you enjoyed the Fender DVD-it's been one of our most popular ever!
Yes, Z'ing is the correct term for the modification you propose, and your methodical and detailed approach is superb! You are guaranteed to have a frame stronger than stock, and one that you'll never have to worry about. I wish more builders put as much thought into their projects up front as you obviously have; we'd see a lot fewer problems if they did!
For butt-welds on 1/8-inch thick material, you only need to bevel the metal from one side. When chamfering the edges, don't chamfer them so much that you leave a sharp point on the metal. Your penetration will be more consistent if you leave a small flat spot on the edges of the metal (about 1/16 inch). In terms of strength, it doesn't matter whether you drill your holes through the frame of the sister plate. I'd suggest drilling the plate, since you can do that in a drill press, and drilling large holes in a frame is rather difficult with a handheld drill. The only other question I have is whether the sister plate will be inside the frame or outside. If you plan to put it inside, I'd trim the edges back a little farther from the flanges on the frame, so you'll have an easier shot at getting a weld on the edges of the plate. If the plate welds on the outside, it's fine just as you show it.
You're welcome to write again if you have further questions!