westend
Audiopile
Well, MaxZ28, with his C36 resto, has inspired me to get going on this pair of JBL4313's that function perfectly but have a heap of cosmetic issues. I thought I might document some of the work and technical bits for this model since what I've been able to find is scattered across a number of sources.
My camera happened to be close so I remembered to take the "before" pictures, for once.:yes:
This morning, I removed the drivers, foilcal that covers the L-pad mounting screws and the L-pad. Later, I'll removing the crossover network so that new binding posts can be installed. For now, I've left it on to prevent dust intrusion.
The woofer is gasketed to the baffle. The mid and tweeter are mounted with screws, only. After nearly 40 years, the drivers need gentle persuasion to remove. I used a small putty knife to slide under an edge and lightly fulcrumed an edge at a time. A little bit of the baffle surface came up but that is OK since they will be repainted and that bit of surface is behind the mounting flanges.
The foilcal was removed with a heat gun set on low and the same process with a putty knife. The L-pad mounting screws are under this thin metal foilcal. After removal, I placed one end of the L-pad board inside the port duct and taped it to the network board. That way, I don't need to desolder it from the crossover and it should be stable when I am shifting the cab around to sand and finish. Later, It will be removed with the network board and the L-pads will get cleaned.
Some links to more technical information and pics of the drivers will be posted later. Now, the cabs need to get masked and then sanded. The last pic attached shows some of the materials I'll be using for the restoration:denatured alcohol to remove dirt, oil, and grunge from the veneer before sanding, sandpaper, color putty for nicks and deep scratches, a color pencil to blend in any abnormalities left after sanding, and Watco oil for the finish.
My camera happened to be close so I remembered to take the "before" pictures, for once.:yes:
This morning, I removed the drivers, foilcal that covers the L-pad mounting screws and the L-pad. Later, I'll removing the crossover network so that new binding posts can be installed. For now, I've left it on to prevent dust intrusion.
The woofer is gasketed to the baffle. The mid and tweeter are mounted with screws, only. After nearly 40 years, the drivers need gentle persuasion to remove. I used a small putty knife to slide under an edge and lightly fulcrumed an edge at a time. A little bit of the baffle surface came up but that is OK since they will be repainted and that bit of surface is behind the mounting flanges.
The foilcal was removed with a heat gun set on low and the same process with a putty knife. The L-pad mounting screws are under this thin metal foilcal. After removal, I placed one end of the L-pad board inside the port duct and taped it to the network board. That way, I don't need to desolder it from the crossover and it should be stable when I am shifting the cab around to sand and finish. Later, It will be removed with the network board and the L-pads will get cleaned.
Some links to more technical information and pics of the drivers will be posted later. Now, the cabs need to get masked and then sanded. The last pic attached shows some of the materials I'll be using for the restoration:denatured alcohol to remove dirt, oil, and grunge from the veneer before sanding, sandpaper, color putty for nicks and deep scratches, a color pencil to blend in any abnormalities left after sanding, and Watco oil for the finish.