Trouble rebuilding a Oro-Phone reproducer

[Tpapp54321]

I just recently have decided to rebuild a Oro-Phone reproducer since it was blasting and it's gaskets looked to be died out but when I went to open it I came across these screws that are perfectly round on the top. I have never seen screws (or whatever they are) like this and do not know how to remove them. Has anybody ever seen screws like this and know how to remove them? Also can I use a Victor Orthophonic diaphragm on this reproducer as a replacement?
Here are pictures of the front and back (the back has the screws)

[Henry]

I'm not familiar with that particular sound box; however, I suspect that those round screw heads without slots may be these: http://www.hansonrivet.com/drive-screws.htm . (I have a Graflex Graphic 2x3 camera with drive screws.) If so, the only way I know to remove them, assuming you can't drift them out from the other side, is to drill them out: an unenviable task, I fear. Carefully file flats on the round heads and use a center punch to make starter holes for your drill. It helps if you have a drill press for the drilling operation!

Another approach would be to cut slots in the round heads with a diamond abrasive cutting wheel (Horror Fright) in a Dremel tool, and then try to back the drive screws out with a screwdriver.

I hope others on the board will be able to provide more helpful (and knowledgeable!) reponses!

[mikejk]

Tpapp54321,
Is your Oro-Phone sound box part of an Edison adapter? I have just finished rebuilding the same sound box that is attached to a tone arm adapter for an Edison DD. I may have been lucky with mine, but I was able to remove the spiral threaded rivets by gripping them with pliers and twisting, or "unscrewing" them out. This deformed the heads quite a bit and they would not hold when reinstalled. I reattached the back by running screws into the original holes. I would be interested in more posts about this one too, because mine does not work very well with low volume despite the rebuild and an airtight seal. It must be the original diaphragm; what is it made out of ? Mike

[Tpapp54321]

I am not sure if it originally came with a Edison adapter because it just came as is attached to a pot metal tone arm from a cheap off brand phonograph. With mine I don't know if it's the gaskets or what but mine also sounds kind of quite and muffled. Maybe that's just how they are but it might just me from my off brand phonograph, I'd like to get a Orthophonic victrola but I'm tight on money from purchasing a victor re-45. And Mike did you replace your diaphragm with a Orthophonic? My diaphragm is still intact just looks to be dirty and kinda worn, if I can get it open I'll be sure to take some pictures of it

[mikejk]

Tpapp,
No, I reused the original diaphragm which was intact, but I am not happy with it. I used hollow rubber tube for gaskets and have an airtight sound box, but volume is low. Mine has a needle bar with two positions, one for a steel needle and another for a shank mounted sapphire for verticals. With two simple twists, the sound box converts into a floating vertical reproducer, really clever but doesn't sound very good. Mike

[Tpapp54321]

Does yours look like mine or like this one?
http://www.ebay.com/itm/Oro-Tone-Chieft ... 7675.l2557
-Tpapp

[mikejk]

Tpapp,
My sound box is the same as yours. Here are some pics showing the positions on the adapter tone arm. The old gaskets were red, so I put red ones back in. I have the Oro-Phone #90 with the same tone arm as the one in the Ebay link, but I couldn't tell if the sound box is the same because the pictures are so small. Mike

[mikejk]

Here's the other Oro-Phone adapter I have. It is the #90 Military, and has a nice metal diaphragm with large center dome and ribbed rings around the outside diameter. It does a nice job with early electric 78's on the Diamond Disc machine, strong with plenty of volume. Mike

[Tpapp54321]

I never realized that this could play Pathés until now, that's pretty cool. I think I might just leave it as is because it doesn't sound too bad just tends to blast and crack on high notes occasionally.
-Tpapp

[mikejk]

Tpapp,
The clever way they designed it to turn over, and at the same time twist in to shorten the tone arm for proper tracking is really neat, just wish it sounded better. With a loud tone needle the volume is better but I too still get crackling on louder passages; I blame the diaphragm but I don't know. Mike