Sucks! Sucks! Sucks!!!
Just spent 4 hours working on the lamp caps to 8x Century #1480 or 2211 (some question) 6x9 Leko’s. I have perhaps an experiential version of this lamp cap which as a G-9.5 medium Bi-focus lamp factory installed. So some question other than the castings saying Century, but re-branded by Major what they are... Probably best guess they are Century #1480 and re/bought and branded for resale by Major in the early 70's. None the less, Excellent optics’ (I’m told) from the mid 60's thru early 70's, think this is the Leko type. I went to High School with in first experience with doing the lighting part of a show with these Leko’s during High School.
The lamp housing castings were easily cleaned, the bolts in really good shape - just a light cleaning and rust inhibitor on them. How I was going to make the separate inlet 2x small Heyco cord grip designed for two or three wire braided asbestos, with 1x terminal outside the fixture for ground; into a #0 sleeved 2-wire SF-2 + grounded lamp casting.. I have a plan and 3/8" NPT Altman cord grips for.
Drill thru the ground casting, and attach it’s longer ground strip length from the inside of the casting. Drill and tap one of the oval Heyco fittings for 3/8" NPT. More difficult but can do even if I have to send to shop machine shop to do, easy to get done. Castings cleaned up great. Easy easy. Semi-skilled to skilled level in drill/tap for cord grip needed TBA, but easy to do.
Onto the lamp sockets. Three of the ceramics of the sockets fell apart on removal. OK. Bryant brand P-28s socket no longer available, and modern replacements are a larger dia. and will not fit in the lamp cap casting. Pulled a few from parts stock, spent an hour breaking apart broken porcelains for the terminals and more especially the square nuts and mounting nuts in making from parts another.
The P-28s lamp socket invention goes back to the mid-1930's and didn’t change at all until about the 1990's for unknown reasons in mounting holes no longer aligning and the OD of it now larger.
On the old Bryant discontinued lamp socket, the square nut to mount the neutral shell of the lamp socket (only one) under the hot connection terminal... I find is the hardest to save once a screw is broken off on it. It is smaller than standard 4-40 square nuts, it’s hard to grab to grind away corroded material so as to remove a broken screw - one in three able to do so. With time possibly some Liquid Wrench might have helped in waiting... but overall the hardest part was that nut under the hot as only part to otherwise make from parts a lamp socket. Got one needed freed up.
I also noted while doing this that the 4-40 porcelain nuts to mount the lamp socket have the same size nut square at the end of it’s rivet nut like different shape. Should you break apart as it were at the square nut / rivet nut porcelain extended nut from the ceramic... you now have two of the proper sized nuts once cut down to just the square nut for future use. Mini sledge hammer... save the nuts from trash from the ceramic for next time. To re-finish the discontinued lamp socket... gotta save what you can on it especially just that nut under the hot contact in what will work.
Three lamp sockets pulled from parts stock and ready once one was finally reconstructed after finding a viable 4-40 square nut from the three lamp bad sockets. Just finished high temp. siliconing up the gap between hot terminal and neutral ground shell square mount on all 8 I need - just a good / modern idea to high temp. silicone that gap..
I have a few more of this lamp socket in stock I am fairly sure, just have to dig bins for them. One pulled from the long term Fresnel to Leko P-28s to P-28s adaptor long term adaptor project. But I’m running out of the very important lamp socket in it’s O.D. which fits mounting holes to most lights, and more important, will only fit in the casting to this Leko fixture.
So silicone done... ready, noticed a chip of the porcelain laying on the table next to a lamp socket. Thought nothing of it and tossed it to the trash in perhaps a part from a broken apart lamp socket. Had another look. Ah’ Snap! That’s another lamp socket breaking apart, and next to it another. Examine all 8 lamp sockets (3-replaced but used), 4x total more with really bad cracks in them and none from the replacement lamp sockets.
Only one out of eight lamp sockets had it’s porcelain lamp socket not un-usable cracked in a way that would fall apart on re-install or use.
That’s a bad day for me. I know I have two more of these Leko’s still hanging at the theater, and doubt I have enough good Bryant ceramics around to replace the lamp sockets for what I need for replacement on for this or future needs. I want to make all the Leko’s viable for some other theater - had to design with clip lights before..., and these are good fixtures, and will be factory spec + better once I’m done.
So last week I finished restoring 6x Fresnels to perfect condition/lamp sockets refinished. They all have Bryant lamp sockets... I know I have enough modern - different mounting lamp sockets to lamp the fixtures.
These Fresnels are done and complete. To take them back apart to remove the lamp sockets which are necessary for the Leko’s and future needs, and re-drill for a new modern one... This is going to be a Suck! So not wanting to do this, not busy at the shop at the moment. My department has stuff to do in always busy, but I just might bring this lamp base swap into them for bulk labor to get re-done. I need the old lamp bases from the Fresnels to make the Leko’s viable, and to save the lamp socket for future work.
On the Leko’s I’ll look into high temp/insulating ceramic padding perhaps between the aluminum cast heat sink and the lamp socket. A bit of cooling, a bit of padding in seeing if a modern upgrade will fit. Think this Leko has a problem in lamp socket crashing into that heat sink given 7/8 at this point, ceramics broken... but the same brand lamp socket Fresnels were fine. Or perhaps the heat sink but thin ceramic base was overheating in some way. Years too late to figure that out. Something I have not seen before, but while the style, I have the theorized G-9.5 prototype only in the museum at this point with experience at this point. It didn't have the problem.
What is not seen in photos on the right is cracks deep into the ceramic sufficient they are bad.
Or is this a systemic Century/Strand #1480 or 2211 problem to be concerned about if one has them still in use?
Really nice lighting fixtures, very well engineered but is this a design flaw say 50 years later - easily perhaps solved but also perhaps too late given a lack of the same style of lamp socket?
Just spent 4 hours working on the lamp caps to 8x Century #1480 or 2211 (some question) 6x9 Leko’s. I have perhaps an experiential version of this lamp cap which as a G-9.5 medium Bi-focus lamp factory installed. So some question other than the castings saying Century, but re-branded by Major what they are... Probably best guess they are Century #1480 and re/bought and branded for resale by Major in the early 70's. None the less, Excellent optics’ (I’m told) from the mid 60's thru early 70's, think this is the Leko type. I went to High School with in first experience with doing the lighting part of a show with these Leko’s during High School.
The lamp housing castings were easily cleaned, the bolts in really good shape - just a light cleaning and rust inhibitor on them. How I was going to make the separate inlet 2x small Heyco cord grip designed for two or three wire braided asbestos, with 1x terminal outside the fixture for ground; into a #0 sleeved 2-wire SF-2 + grounded lamp casting.. I have a plan and 3/8" NPT Altman cord grips for.
Drill thru the ground casting, and attach it’s longer ground strip length from the inside of the casting. Drill and tap one of the oval Heyco fittings for 3/8" NPT. More difficult but can do even if I have to send to shop machine shop to do, easy to get done. Castings cleaned up great. Easy easy. Semi-skilled to skilled level in drill/tap for cord grip needed TBA, but easy to do.
Onto the lamp sockets. Three of the ceramics of the sockets fell apart on removal. OK. Bryant brand P-28s socket no longer available, and modern replacements are a larger dia. and will not fit in the lamp cap casting. Pulled a few from parts stock, spent an hour breaking apart broken porcelains for the terminals and more especially the square nuts and mounting nuts in making from parts another.
The P-28s lamp socket invention goes back to the mid-1930's and didn’t change at all until about the 1990's for unknown reasons in mounting holes no longer aligning and the OD of it now larger.
On the old Bryant discontinued lamp socket, the square nut to mount the neutral shell of the lamp socket (only one) under the hot connection terminal... I find is the hardest to save once a screw is broken off on it. It is smaller than standard 4-40 square nuts, it’s hard to grab to grind away corroded material so as to remove a broken screw - one in three able to do so. With time possibly some Liquid Wrench might have helped in waiting... but overall the hardest part was that nut under the hot as only part to otherwise make from parts a lamp socket. Got one needed freed up.
I also noted while doing this that the 4-40 porcelain nuts to mount the lamp socket have the same size nut square at the end of it’s rivet nut like different shape. Should you break apart as it were at the square nut / rivet nut porcelain extended nut from the ceramic... you now have two of the proper sized nuts once cut down to just the square nut for future use. Mini sledge hammer... save the nuts from trash from the ceramic for next time. To re-finish the discontinued lamp socket... gotta save what you can on it especially just that nut under the hot contact in what will work.
Three lamp sockets pulled from parts stock and ready once one was finally reconstructed after finding a viable 4-40 square nut from the three lamp bad sockets. Just finished high temp. siliconing up the gap between hot terminal and neutral ground shell square mount on all 8 I need - just a good / modern idea to high temp. silicone that gap..
I have a few more of this lamp socket in stock I am fairly sure, just have to dig bins for them. One pulled from the long term Fresnel to Leko P-28s to P-28s adaptor long term adaptor project. But I’m running out of the very important lamp socket in it’s O.D. which fits mounting holes to most lights, and more important, will only fit in the casting to this Leko fixture.
So silicone done... ready, noticed a chip of the porcelain laying on the table next to a lamp socket. Thought nothing of it and tossed it to the trash in perhaps a part from a broken apart lamp socket. Had another look. Ah’ Snap! That’s another lamp socket breaking apart, and next to it another. Examine all 8 lamp sockets (3-replaced but used), 4x total more with really bad cracks in them and none from the replacement lamp sockets.
Only one out of eight lamp sockets had it’s porcelain lamp socket not un-usable cracked in a way that would fall apart on re-install or use.
That’s a bad day for me. I know I have two more of these Leko’s still hanging at the theater, and doubt I have enough good Bryant ceramics around to replace the lamp sockets for what I need for replacement on for this or future needs. I want to make all the Leko’s viable for some other theater - had to design with clip lights before..., and these are good fixtures, and will be factory spec + better once I’m done.
So last week I finished restoring 6x Fresnels to perfect condition/lamp sockets refinished. They all have Bryant lamp sockets... I know I have enough modern - different mounting lamp sockets to lamp the fixtures.
These Fresnels are done and complete. To take them back apart to remove the lamp sockets which are necessary for the Leko’s and future needs, and re-drill for a new modern one... This is going to be a Suck! So not wanting to do this, not busy at the shop at the moment. My department has stuff to do in always busy, but I just might bring this lamp base swap into them for bulk labor to get re-done. I need the old lamp bases from the Fresnels to make the Leko’s viable, and to save the lamp socket for future work.
On the Leko’s I’ll look into high temp/insulating ceramic padding perhaps between the aluminum cast heat sink and the lamp socket. A bit of cooling, a bit of padding in seeing if a modern upgrade will fit. Think this Leko has a problem in lamp socket crashing into that heat sink given 7/8 at this point, ceramics broken... but the same brand lamp socket Fresnels were fine. Or perhaps the heat sink but thin ceramic base was overheating in some way. Years too late to figure that out. Something I have not seen before, but while the style, I have the theorized G-9.5 prototype only in the museum at this point with experience at this point. It didn't have the problem.
What is not seen in photos on the right is cracks deep into the ceramic sufficient they are bad.
Or is this a systemic Century/Strand #1480 or 2211 problem to be concerned about if one has them still in use?
Really nice lighting fixtures, very well engineered but is this a design flaw say 50 years later - easily perhaps solved but also perhaps too late given a lack of the same style of lamp socket?
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