G-38 Lamp Socket Extenders
So anyone ever used a E-26 (medium screw) lamp socket extender before, such as to make a 150w A-21 strip light fixture into a A-19 fixture in using the lower wattage more efficient lamps? This I did a lot back when Osram had a 100w halogen A-19 lamp. Even used them in combination with E-39 (Mog Screw) lamps in making them into A-19 lamp fixtures. Such as a E-39 500w ancient PC fixture, into a 400G-30SP lamped fixture in working correctly.
Lamp socket extenders for the E-26 size somewhere back when they were invented, were designed so as to adapt and extend the seat height between one lamp to another. I don’t think by chance a A-21 fixture now with a lamp socket extender bench focus’s to A-19.
So, today came up from a designer, he wants some 10Kw and 5Kw studio fixtures converted to 2KW lamps. 10Kw DTY (LCL of 10"), 5Kw DPY (LCL of 6.1/2"), converted to 2Kw CYX (LCL of 5").
Last week I had a similar inquary for the first time in a few years about some 5Kw fixtures to be lampped at 2Kw, but they were fine with the lamps out of focus - they were prop lights. Been a few years since I did such a downgrade. Why pay for on-site powering up 5kW Dimmers if only wanting 2Kw of light, and bleed the amber shift? In the past years in doing this, I also had a lot more lead time so as to deconstruct the fixture and jack that lamp base up to it’s new proper seat height. And I did master that G-38 to E-26/A-19 lamp adaptor. (Still in works the P-28s to P-28s socket extender).
Shorter notice these days in such projects, and more projects to get done.. But on the other and the current shop has metal workers and complete machine shop.
First did a little research into if it’s been done already. Still waiting on Bulbtronics for reply, but it’s possible I can buy such a thing done. In the mean time I bought some male to female standoffs of appropriate size (in stainless and aluminum - neither would work other than for R&
D.) Pins for a G-38 lamp are 7/16" Dia... and for the 5Kw upgrade I would need to jack the lamp up by 1.1/2" Thinking brass for a 2Kw lamp end result for the lathe. 10-32 set screw to secure to the CYX lamp pins.
Unfortunately in checking ceramic spacers for insulators.... nothing like this.... but minds eye tells me there is stuff out there. Questioning if say porcelain knob and tube insulators are still on the marker and what sizes they are... as a for instance. (Have one in the hall of shame collection to pull out, but think too small.) Given that... My old Cotronics ceramic epoxy.... making an insulator mold for creating an insulator around the brass adaptor with set screw pin securing. As long as post-heat the ceramic epoxy after application... should have either for each pin would work. Would like to do a dual pin adaptor, but think that would be too much material short of cutting away and casting the actual ceramic cups to bad CYX/DPY lamps. Just too much epoxy ceramic in use to trust it won’t crack.
Inspired. What am I not considering? Given fab shop is way too busy to make these adaptors for this project, but I think such adaptors will be useful to fabricate. What am I missing... grade of brass to specify? I know putting a set screw into the pins of a perfectly good CYX lamp (it’s hollow) will have to be done to a torque... perhaps two set screws. Also, stainless steel set screws would probably be best - while they don’t conduct as well... less chance of corrosion within the ceramic epoxy or brass.
Set screws will be tapped into the brass so going 10-32 say other than pointed or cup point allows for the most pressure to the pin of the lamp without making damage to it. Install the set screws where the G-38 lamp socket has the least effect on it’s clamping for future use of the CYX lamp in a 2Kw fixture.
Spray the formed brass extensions with electrical contact cleaner w. lubricant or apply Craig Deoxident with (copper). Molds and release will take me back to college, sand blast and blow off the exposed to ceramic epoxy parts I’m glueing to.
What am I missing?
So anyone ever used a E-26 (medium screw) lamp socket extender before, such as to make a 150w A-21 strip light fixture into a A-19 fixture in using the lower wattage more efficient lamps? This I did a lot back when Osram had a 100w halogen A-19 lamp. Even used them in combination with E-39 (Mog Screw) lamps in making them into A-19 lamp fixtures. Such as a E-39 500w ancient PC fixture, into a 400G-30SP lamped fixture in working correctly.
Lamp socket extenders for the E-26 size somewhere back when they were invented, were designed so as to adapt and extend the seat height between one lamp to another. I don’t think by chance a A-21 fixture now with a lamp socket extender bench focus’s to A-19.
So, today came up from a designer, he wants some 10Kw and 5Kw studio fixtures converted to 2KW lamps. 10Kw DTY (LCL of 10"), 5Kw DPY (LCL of 6.1/2"), converted to 2Kw CYX (LCL of 5").
Last week I had a similar inquary for the first time in a few years about some 5Kw fixtures to be lampped at 2Kw, but they were fine with the lamps out of focus - they were prop lights. Been a few years since I did such a downgrade. Why pay for on-site powering up 5kW Dimmers if only wanting 2Kw of light, and bleed the amber shift? In the past years in doing this, I also had a lot more lead time so as to deconstruct the fixture and jack that lamp base up to it’s new proper seat height. And I did master that G-38 to E-26/A-19 lamp adaptor. (Still in works the P-28s to P-28s socket extender).
Shorter notice these days in such projects, and more projects to get done.. But on the other and the current shop has metal workers and complete machine shop.
First did a little research into if it’s been done already. Still waiting on Bulbtronics for reply, but it’s possible I can buy such a thing done. In the mean time I bought some male to female standoffs of appropriate size (in stainless and aluminum - neither would work other than for R&
D.) Pins for a G-38 lamp are 7/16" Dia... and for the 5Kw upgrade I would need to jack the lamp up by 1.1/2" Thinking brass for a 2Kw lamp end result for the lathe. 10-32 set screw to secure to the CYX lamp pins.
Unfortunately in checking ceramic spacers for insulators.... nothing like this.... but minds eye tells me there is stuff out there. Questioning if say porcelain knob and tube insulators are still on the marker and what sizes they are... as a for instance. (Have one in the hall of shame collection to pull out, but think too small.) Given that... My old Cotronics ceramic epoxy.... making an insulator mold for creating an insulator around the brass adaptor with set screw pin securing. As long as post-heat the ceramic epoxy after application... should have either for each pin would work. Would like to do a dual pin adaptor, but think that would be too much material short of cutting away and casting the actual ceramic cups to bad CYX/DPY lamps. Just too much epoxy ceramic in use to trust it won’t crack.
Inspired. What am I not considering? Given fab shop is way too busy to make these adaptors for this project, but I think such adaptors will be useful to fabricate. What am I missing... grade of brass to specify? I know putting a set screw into the pins of a perfectly good CYX lamp (it’s hollow) will have to be done to a torque... perhaps two set screws. Also, stainless steel set screws would probably be best - while they don’t conduct as well... less chance of corrosion within the ceramic epoxy or brass.
Set screws will be tapped into the brass so going 10-32 say other than pointed or cup point allows for the most pressure to the pin of the lamp without making damage to it. Install the set screws where the G-38 lamp socket has the least effect on it’s clamping for future use of the CYX lamp in a 2Kw fixture.
Spray the formed brass extensions with electrical contact cleaner w. lubricant or apply Craig Deoxident with (copper). Molds and release will take me back to college, sand blast and blow off the exposed to ceramic epoxy parts I’m glueing to.
What am I missing?
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