The Sknat!; Another day, another soundbox!

[emgcr]

Difficult to tell from the photos but does the back you have removed have an external diameter greater than that of the main case ? If it does and you are going to try Mike's vice method (which could be tricky on such thin metal) I would still remove the stylus assembly whose screws just could be holding or locating in something unseen ?

[JerryVan]

How does the back plate locate on a tone arm? Is there a locating pin, such as used by Victor/HMV? Or does it clamp in place, as I understand a Meltrope does?

If there is a locating pin, then the aluminum plate does not screw in, because there would be no predictable place where the aluminum plate would tighten and the orientation would be off. If you can mount the reproducer with no specific orientation to the tone arm and then clamp it in place, the variability of aluminum plate position would pose no problem and suggest that it may be threaded in place.

Rather than risk the back plate as your wrench/tool to unscrew the aluminum plate, perhaps get a rectangular piece of metal or hard wood, drill 3 holes in it at one end, attach it to the plate, and use it as a wrench to unscrew the plate. I would definitely heat the reproducer body first to melt any old contamination that may be essentially gluing everything in place. Maybe just placing in boiling water would suffice for that.

If it turns out to be pressed together, then a special puller must be made in order to save the diaphragm.

[Ahmed]

Many thanks all for your input and suggestions. Next step when I have a chance it make a rig with some pins to give me some leverage when trying to unscrew it. I shall get there one way or another (let's just hope it's worth the effort!)

There's no locator pin on the back; it's a rubber fitting like in the Meltropes. The state of that (hard as rock!) is what's making me determined to replace the gaskets which in all likelihood are equally bad

[drh]

Just as a crazy idea, could it be reverse threaded? If so, and if you were turning it in the conventional way, your attempts to unscrew it would just be making it tighter.

[walser]

Hi Ahmed

Just one suggestion. Make a scan or very good and perpendicular picture of the aluminium plate before trying to open it. In case it gets damaged during the opening, you send me the image and I can make a replacement with the holes of the screws in the correct place.

Good luck and keep us informed about your progress.

Regards

Pedro Martinez
www.pedrofono.com

[chunnybh]

My memory is terrible. Years ago I did rebuilt one of these. I am pretty certain the two stylus bar mounting screws also secure the bottom of the aluminium plate. The top of the aluminium plate has a lug that slots into the top of the body. Once the two screws are removed, try teasing out the bottom of the plate. It might be easier to get a grip if you screw the back plate back on. I could be wrong!.

[Ahmed]

Hi Ahmed

Just one suggestion. Make a scan or very good and perpendicular picture of the aluminium plate before trying to open it. In case it gets damaged during the opening, you send me the image and I can make a replacement with the holes of the screws in the correct place.

Good luck and keep us informed about your progress.

Regards

Pedro Martinez
http://www.pedrofono.com

Good shout, thanks Pedro! I'll take pictures and measurements next time I'm working on it

@chunnybh Lovely, I'll probably have it open again this weekend and will try prying it out as described

[Ahmed]

Alrighty, it's open!

The aluminium plate is indeed threaded, and the screws holding the needle bar assembly don't have anything to do with holding it in place.

In the end, I ended up prying it open, and pressing it back shut.... Not ideal, nor how I normally work, but it was coming apart wether it cooperated or not!


Here it is singing for the first time this evening; I'm rather pleased with its tone!

https://youtu.be/5LbWMmmn_a8


Still needs some tweaking to get rid of a minor buzz, and currently working on replacing the rock hard rubber connector

[VanEpsFan1914]

Congratulations on a job well done, Ahmed; I've been watching the thread through finals & it looks like you did have your hands full. Wonderful work.

[nostalgia]

Yes, congratulations on the excellent work done, and that video really gave me good Christmas vibes too:)
Thanks a lot for sharing !