Okay, it's time to tackle fender mounting on your project, but you want the finished assembly to be rock solid. Can't blame you for that. In this installment of ChopCult Metal Shop, guest fabricator Jason Roche at Special '79 attacks the problem with customary skill. Class is now in session.
The materials for these struts can vary, but my choice for these struts is to use 304 stainless, 5/16”-18 x 1” threaded bungs and matching counterbore bungs for allen head cap bolts available at Lowbrow Customs. I believe they even sell a complete kit that includes everything you need for this project. I already had some ½” stainless rod stock, so I’ll just be using the bungs I scored from them.
I’ll be using a TIG welder to weld these struts but you can chose a MIG or gas setup if you’re more comfortable with that. Besides the welder, the only other specialized tools being used are an angle grinder (with a flap wheel and some cutoff discs) and an oxy-acetylene torch.
The first thing you need to do is to determine the connection points where you’ll want to bolt the struts. On the fender itself, I like to brush on some blue machinist layout dye so I can easily see the areas I scribe the center marks I’ll be drilling out. The same goes for the areas on the axle plates for the lower mount point. Use a center punch to mark the center for drilling on the fender and drill out a hole with a step bit all the way up to ½” (you can skip this step, read below). The lower mounting holes on the axle plates will be drilled to 5/16”.
At this point, I cut one of the 5/16”-18 x 1” bungs in half and turn down one side in the lathe to ½” in diameter and 1/8” in depth. I’m doing this so it will plug into the holes we drilled in the fender and help with holding the bung in place while welding. The drilling of the fender and turning down of the threaded bung can be skipped if you don’t have a lathe; just weld the bung to the fender without being a fancypants like me. Tack and weld the threaded bungs to your fender. After they cool, bolt the counterbored bungs to the threaded bungs on your fender with your allen cap screw.
I like to weld a longer piece of the ½” stainless rod to one of the counterbored mounting bungs so I can bolt it to the hole I drilled in the axle plate and have a nice solid mount to heat with an oxy-acetylene torch and bend the strut to the shape I want. After I’m happy with the bends, I’ll let the strut cool and pivot it up to the counterbored bung we mounted to the bung on the fender, mark and cut the strut to the length needed. Once a good fit is achieved, tack the bung solidly and remove for final welding. Check strut fit after cooling and adjust if needed. Repeat techniques for the second strut.
Your fender should now be strong enough to hold whatever size female you can talk into riding on the back of your two-wheeled deathtrap.
SPCL79 Fabrication, over and out, stay gold, keep on keepin’ on, or add your favorite catch phrase here.