Edison Model C reproducer repair

[jboger]

I have a broken Model C Edison reproducer. I've included two photos. The problem is that a hinge screw has broken so that the reproducer is now in two parts. This looks like this could be a common failure point as the two pieces are held together by this one screw.

I'd like to repair this reproducer. I've gone to one of our part supplier websites (there are several and all good). I found what seem to be possible candidates for a repair. I think the part is called a "reproducer hinge block". They also seem to be cast in one part with the screw part of the casting. These seem to be the possible candidates for my Model C reproducer but am not sure:

Reproducer Hinge Block ON 220CN
Reproducer Hinge Block 0-80 220BN (Oversized Threads 0-80)
Reproducer Hinge Block

The last one is simply identified as Reproducer Hinge Block. It looks the closest to my Model C. It also looks to be a rather poor casting. And it is sold out.

There is also this item:

Edison Reproducer Hinge Block Screw Model C/H/K (added later: I now know this is not relevant to my problem.)

This looks like something that screws into the hinge block, whereas the hinge block for my Model C screws into the body of the reproducer.

Sure could use some help here.


John

John

[FellowCollector]

Hi John
I can't tell you how many of these Edison model C and model H reproducers I've found over the years with the broken hinge block. The most difficult part of your repair will be to remove the other end of the threaded hinge block pin that remains inside the reproducer body. It will need to be drilled out and tapped to accept the new threaded pin on a replacement hinge block. It's tricky work since the wall of the reproducer is already quite thin. The late Ron Sitko used to drill out all of my Edison C and H reproducers that had broken hinge blocks like yours. Without Ron Sitko the next person I've been just saving mine up hoping to find someone else who will do this sort of work for a reasonable fee. If you have a drill press and the correct size drill and tap you might be lucky and be able to do it yourself. Best wishes and good luck!

Doug

[jboger]

Doug:

Thanks for your response. Yes, I see that problem, the broken end of the screw that remains in the body of the reproducer. I still hope there may be a replacement hinge block with the proper threads so that if I do manage to remove the broken end of the screw, I would then only need to screw in a new hinge block.

If you look at the face of the reproducer, near the top is a hole through which you can see the other end of the broken screw shaft still embedded in the reproducer. Wouldn't it have been nice if Edison had put a slot in the end so that all one needed to do is take a small screwdriver, insert it into that hole, find the slot, then back off the screw?

John

[ChesterCheetah18]

I would suggest contacting Wyatt Marcus ( MicaMonster here on the forum).

Steve

[NEFaurora]

APSCO Online sellls good Model C/H Reproduction reproducer hinge blocks for about $26 plus shipping. I've tried them and they work well... ) Tony K. (Edison Collector/Restorer)

[RefSeries]

As has been said, the remaining bit of the screw is a common problem and very fiddly to fix. Drilling can be done, but it needs great care and a good modelmakers' drill stand like a Proxxon or a Dremel. Do not attempt it by hand or you will wreck the existing thread in the hole for sure. The quick and dirty way is to drill it out, tap an oversize thread and use a replacement block with a larger screw, but I have had some success in getting the broken stump out and it is worth trying that first.

I soak the hole with the broken part in penetrating oil for a couple of days to give the broken bit a bit of lubrication, then with a fine scribe try to scratch a slot in the broken end. Use as little force as possible as you don't want to damage the thread or splay the end of the broken bit. I have found that after a while you can make a small slot in the stump which a small watchmakers' screwdriver can accept, and with luck and a bit of pressure this allows one to unscrew the bit from one side or the other. You will need a jewellers' loupe or eyeglass to see inside the hole as obviously it is very small.

If this doesn't work try drilling, but it helps hugely if you can create a centre pop in the stump with a scriber or similar, to reduce the odds of the drill wandering into the threaded hole. Use as little pressure on the drill as possible. Interestingly have found that once starting the drilling sometimes the screw has come loose and unscrewed itself, which is great, but don't bank on it.


If all this fails, send the thing to a professional who can do it properly!

Keith

[kendphono]

A word of caution. As a restorer who has done a great number of these, if you do not have the proper tools or anyone with expertise to guide you, don't do anything. There are things that you can do that will make it extremely difficult to do a follow on repair. A restorer would prefer to have the unmodified part to work with. That makes the repair relatively simple. Having to also repair a failed attempt ar repair makes it much more difficult. So, I would recommend sending the part to someone that has done them before and who has a lot of experience in doing them.

Ken Danckaert