Well I’m still working on the rear bumper mold in between hoods. I completed the current hood in less than 10 days! I should have the mold center section completed this weekend which is thick fiberglass about five times thicker than a hood Then I just have add bracing to the back and then layup the little end pieces since it’s a multiple piece mold but that won’t take me long. So I am still working on it little at a time.
I finished applying the last layer of fiberglass on the center section this evening. Tomorrow I have to pop a new hood out of the mold and get that dressed and ready for shipment but after that I’ll continue working on this bumper mold! I remember what a PITA it was getting the hood mold off of the hood plug hopefully this one won’t be quite as difficult since it’s not as big
I got a front 71 done by someone in Canada many moons ago....can't remember who it was but at the time only one making them for 71.
Yeah I wanted to try a bumper and from what I read and could see on the web the 71 rear wasn't available. So I thought I'd give it a shot. The mold will cost me probably $500 by the time it's complete, I owe the first bumper to a member who gave me the steel bumper to make the mold for the bumper, so I'll just have to sell a few to recoup my cost for materials.
Well I finished the large center section of the mold. I added feet, bracing and a paint job The paints really just to minimize little glass shards sticking you when you move the mold around. So I flipped the mold over on the table and started working on the flanges. As you can see here, this little lip (in gray) curls around the sides of the bumper would make getting the part out of the mold a serious PITA! Not to mention getting the steel bumper and mold to release from each other! So I have to finish cleaning up the residual clay and trim the edges. Then I can lay up the glass on the gray section and the orange flange. As with the sides of the bumper, those little tabs on the bottom of the bumper would cause some issues too. So it'll be clean, prep and layup these two sections as well. Once that's complete, the fun starts! I'll pull the four little sections off and then try to separate the main mold from the steel bumper. Getting the part out of the mold is typically rather simple, but here because the mold is almost 5 times thicker than a bumper will be, the mold nor the bumper are going to flex much!
Man this thing fought me getting the steel bumper and the mold separated! It took me over two hours with hammers and crowbars and pry bars, wood and more. But I finally set it free. There’s a few small scratches in the mold that’ll be an easy fix. You can see the steel bumper laying in the foreground and the mold in the background. I have to finish cleaning the new mold up, trim the edges flush and then I’ll post some better pictures of the mold.
Well I finished trimming the mold and touched up some spots that were scratched or chipped prying the two parts apart A little sanding of the touch ups tomorrow, shoot some gel coat and do the final buffing.
I'll tell you if I make another bumper mold I will definitely reevaluate where I put the mold parting lines! I should probably make the whole end sections removable, I think that is what was really keeping the mold from easily releasing from the bumper.
Yeah after I get the first bumper laid up I’ll have an idea of how much materials will cost per bumper and I’ll know how much labor each one requires. Then I can size a box and see what shipping will be, hopefully not as high as a hood
Very interesting, I keep following your threads even though I do not need the parts (at least right now). Don't you think that will be similar when trying to get the fiberglass bumpers out of the mold? Or are they more flexibel compared to the steel bumper?