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Hello Ron. I hope it is O.K. that I post this in your electro forum. I have to come back to you regarding the clip-in bulb holders used in our Andromeda 4 machines but maybe in a little bit different way as you would have expected. :-) In the other thread I stated "I cannot see how these could be repaired" but obviousely one must look first to see something. In fact the only thing needed is one blind rivet, some standard tools and some time...... :-) 01. loose bulb holder So I had a closer look at the bulb holders that are very loose and noticed that the center contact shaft is exposed at some places and could cause a short as also the soldering lugs for the two contacts can freely rotate on these holders. 02. Disassembly I removed all solder and the little wire that connects the centre contact pole with the soldering lug and used a small bench vice to round the flat end of the center pole so it could slip through the hole in the holder. 03. The parts Pulling out the center piece the whole holder falls into its 14 parts. One blind rivet should hold everything together. The 15th part on the picture, the one in fron t of the line the others are lined up, is the rivet collar that has faild and was broken from the rivet. Looking at the parts it seems clear: if one of the solder lugs can be rotated or if there is any slot between the isolating plates the central rivet has failed already. 04. The replacement I found out that 3.2 mm x 9 mm blind rivets are a good, cheap and nearly perfect replacement. I will come back to the "nearly" a little bit later. So I removed the steel center shaft from the blind rivets and started to bead the original parts on it. In the picture you also can see the really small collars broken of the original rivets. 05. Reassenbly I found a hex-wrench in a size that the sleve of the bulb holder just fitted over it. I mounted it in my bench vice as an anvil for the re-riviting. 06. Riveting 1 First I used a center punch to broaden the rivet and fill the rectangular hole on the last metal grommet. After that it looked like in pic. 07. 08. Riveting 3 Then I used a simple M4 screw to flat it out. The result is shown in pic. 09. 10. Drilling Now I have to come bach to the "nearly" from the beginning of this post. The diameter of the hole through this rivet is 0.1 mm to small to put the center shaft in again. I first tried to use my Dremel to drill it but as one cannot securely fix this delicate bulb holder in a vice and as aluminium is very soft the drill just got cought in the rivet and ruined my work. So I still use the Dremel but not plugged into the mains but operated by hand and slowly drilling through the rivet with a 2.1 mm drill. The aluninium is soft; it takes only one to two minutes maximum. 11. Parts left After freshla riveting the bulb holder the moddle part in this picture should appeare like one single item; no piece shold move, nothing should rotate. Just a small assembly step left. 12. Center contact and spring Now the spring is mounted on the center contact and the center contact is inserted in the holder; it helps a lot inserting a bulb to fix it there. The smalles flat washer is also maounted now. 13. Secure center contact Using the vice the initial flat portion of the center pole is re-created so that it doesn't disassemble itself when the bulb is taken out. That should look about like in pic. 14. 15. Solder center wire The small wire to the center conatct is maounted again 16. Finished And the bulb holder should be good for another 39 yaers, I hope. Readdy to go back into the machine. If all tools and parts are on the work bench I estimate 15 to 20 minutes per bulb holder repair; unfortunately I have about 8 I have to do still.... :-) I never thought someone could write anything about bulb holders longer than 3 lines; looks like I was wrong..... :-) Best regards, Andreas from Vienna
