CA77 Lamp conversion

Seadog · Post by **Seadog** » Sun Mar 15, 2015 8:17 am

Thanks to G-Man and Mike. I try and I enjoy both the planning and the work, but I don't have your bike specific experience or a lot of tools beyond the normal homeowner/hobbyist variety. Your encouragement means a lot.

My next challenge is to find a place locally to buy flux for steel soldering. I might have to order it on-line.

For now, on to other things; I have a petcock rebuild to master and am not having any luck so far.

G-Man · Post by **G-Man** » Sun Mar 15, 2015 10:14 am

Seadog

I have used phosphoric acid to assist with soldering steel but I think I would be tempted to have a go with some steel-loaded epoxy resin to hold the lamp holder in. I just cannot remember what it's called.

I would be concerned that the heat might screw up the reflector surface. It's always good to experiment and learn from it, though.

G

Seadog · Post by **Seadog** » Sun Mar 15, 2015 10:59 am

G-Man wrote:Seadog

I have used phosphoric acid to assist with soldering steel but I think I would be tempted to have a go with some steel-loaded epoxy resin to hold the lamp holder in. I just cannot remember what it's called.

I would be concerned that the hear might screw up the reflector surface. It's always good to experiment and learn from it, though.

G

I was just cleaning up the scrap bits that I removed from the bulb socket and the back of the headlight. Together, they'll be my soldering test piece, once I find flux. As I was removing the burrs, I noticed that the reflective surface is quite fragile. Epoxy might be the better idea, but unlike solder, I'd have to create a fillet, which I'd have to keep it out of the cutouts for the wire bail in the bulb socket.

All sorts of epoxies are available, such as JB Weld, LocTite, Quiksteel, Gorilla, etc. Even if I go with epoxy, I'll try the soldering on the test pieces, just because I've never soldered steel before.

Seadog · Post by **Seadog** » Fri Mar 20, 2015 9:25 am

I used a heat resistant version of JB Weld today to join the lamp base to the headlamp. Once it sets up, I'll file and shape the epoxy, then repaint the back of the lamp. I wish that I could have soldered it, but I couldn't find the flux and I didn't want to damage the reflective coating. Notice that I left gaps in the epoxy to accomodate the bulb and the wire bail that holds the bulb in place.

deafanddiabetic · Post by **deafanddiabetic** » Fri Mar 20, 2015 10:08 am

Great pictures, Seadog.

Mine was not nearly as pretty, but that's basically the process that I did.

I cut out the bulb, desoldered the base, found a cheap cheap cheap bulb holder at Advance Auto Parts, soldered it into the hole in the headlight bucket and now I can swap H4 bulbs out like it's nobody's business. Took all of an hour and total cost about $7. It's pretty messy back there though, haha.

Seadog · Post by **Seadog** » Fri Mar 20, 2015 12:09 pm

deafanddiabetic wrote:Great pictures, Seadog.

Mine was not nearly as pretty, but that's basically the process that I did.

I cut out the bulb, desoldered the base, found a cheap cheap cheap bulb holder at Advance Auto Parts, soldered it into the hole in the headlight bucket and now I can swap H4 bulbs out like it's nobody's business. Took all of an hour and total cost about $7. It's pretty messy back there though, haha.

Thanks. Wish that I could have found the bulb holder locally (and cheaply). If the epoxy that I used doesn't hold, I'm going to try soldering. When you soldered yours, did you have any trouble with the reflective coating inside the headlight? Use an iron? What did you use for flux?

deafanddiabetic · Post by **deafanddiabetic** » Fri Mar 20, 2015 3:37 pm

No problem with the reflective coating, I think mostly because the soldering was all applied to the back of the contoured casing. I'm pretty sure I used Rosin Core 60/40. It's held on, taken the heat, and seems like it's working alright. It was pretty shoddy and quick, honestly totally on the fly one afternoon in the dungeon and now I see that others have tried the same method with success.