Cossor 501 project.

[electronicskip]

Finally collected my Cossor 501 today (thank you Greg Simons)
Looks like another total rebuild restoration to go with my 1949 Marconi which I'm also very slowly bringing back to life.

Fist impressions are everything is there at least ,all caked in decades of grime and rust.
First thing it needs is a new Speaker/Tuning glass surround as the one on it is very brittle and snapped so if anyone can help id be very grateful.
Believe it or not although the cabinet is some sort of plastic the wooden square the speaker is mounted on has woodworm! those darn woodies get everywhere so ill be replacing that too asap.
Couple of pictures to start.

[kalee20]

I've got a Cossor 500 (wooden cabinet, same chassis). Crummy sensitivity, but good sound quality.

Yours has a different mains transformer - mine is mounted BELOW the chassis, with the voltage selector and winding bulge peeping through!

Good luck - will watch the thread with interest. It's an easy set to work on!

[electronicskip]

Thanks.
I'm not the best restorer, my main tool tends to be a hammer !! only joking but anything too complicated and I'm stumped.

[Cobaltblue]

Unfortunately that plastic surround is virtually always shrunk, cracked or just plain missing! but good luck finding a replacement

That chassis was around for a while and I think the last hurrah was the 520 having started as the 494.

Different valve line ups and minor changes.

I must admit I prefer the 494 it doesn't work any better but it doesn't have that plastic surround

It should be remembered that the internal aerial is described as for "local stations" It was designed for use with an external long wire aerial

Cheers

Mike T

[crackle]

I restored one of these what seems like ages ago but it was probably only 6 years.
The plastic trim around the front shrinks and all the pegs which hold it in place tend to snap off. If there are any which are left then file the holes for them into a slot so that they fit back in.
You should be able to glue the cracked plastic trim together with superglue to make a fairly invisible joint.
I used epoxy glue to refit the trim onto the front of the cabinet.
After a wash with something like spray kitchen cleaner, the rest of the case should polish up to a lovely mottled chestnut colour with a deep shine, or at least my one did after a vigorous rubbing with Bakelite polish.

Be careful how you clean the dial glass especially the back where the printing is. A lot of modern detergents can remove old paint from dial glasses.

The radio sounds quite good when working, but I seem to remember they were not the most sensitive of receivers.
There is a fine example of how one can look on the Radio Museum. https://www.radiomuseum.org/r/cossor...er_501_ac.html
Mike

[Sideband]

Yes don't expect miracles reception-wise. I spent ages checking alignment and trimming the set to absolute peak but it only made a marginal difference. Even on a long wire aerial it struggled with some of the more distant stations. On the good side, they are easy to work on and look great when the bakelite cabinet and surround have been restored.

[electronicskip]

Originally Posted by Cobaltblue

Unfortunately that plastic surround is virtually always shrunk, cracked or just plain missing! but good luck finding a replacement

The plastic surround is just snapped in one place, its not too bad shrinkwise so ill probably have to get a 3D Printer to reproduce one as I have access to one with a bit of begging.

[greg_simons]

Glad you like the cossor and have made a start on it, hope you liked the super lethal electric light bulb mains adapter!.
greg.

[Jonster]

Good luck with the restoration, I had a similar one years ago, the sound via the gram input wasn't bad I remember using it with my old Stella tape recorder as the amp and speaker (think it's an 8") sounded far better.

[electronicskip]

Originally Posted by greg_simons

Glad you like the cossor and have made a start on it, hope you liked the super lethal electric light bulb mains adapter!.

You mean its not original equipment? hahahaha
Seriously yes I made a start within 30mins of getting it home thank you.

[Boater Sam]

Had many of these from 494 to 520 models. They all suffer from having the bottom coupled aerial coils.
Wonderful mixture of valve types used, even in the same set. The 6V6 output are the best.
The dial glass printing is originally in 3 colours on most but some are in 2 colour, all will lose the printing very easily with the lightest of touches or any water.

[electronicskip]

Well ive spent most of the day stripping the Cossor,most things were rusted up or broken but I managed to get it apart.
As you can see from the pictures ive taken , the woodworm had totally eaten the loudspeaker surround so ive used the old one as a template to start cutting out a new one ready for final fitting.
Ive spent a few hours restoring the casing and its come up really well, its going to be a sympathetic restoration so it wont be perfect but I'm pleased with the results.
Ive cleaned up the back cover too and rewound the built in Aerial attached to it.

I ran up the loudspeaker and it seems to work fine so I will be retaining it.
Here are a few pictures so far.

[electronicskip]

Originally Posted by Boater Sam

Had many of these from 494 to 520 models. They all suffer from having the bottom coupled aerial coils.
Wonderful mixture of valve types used, even in the same set. The 6V6 output are the best.
The dial glass printing is originally in 3 colours on most but some are in 2 colour, all will lose the printing very easily with the lightest of touches or any water.

My dial glass is a 3 colour version.
I've cleaned it with a small paint brush just dampened and used blotting paper very lightly to dry it off and I'm happy to say it,s worked a treat with no uplift.

[Boater Sam]

Well done, I have had to remake several with waterslide when the printing has just wiped off with a dry cloth.

[mark2collection]

I shall be watching this post with great interest.

Below, pictures of the set I collected yesterday, this being my first encounter with a Cossor set. Appears to be original/untouched. Amazing how different it is from your set ...

I like the look of them, it's a fair size too. The bezel/surround is loose & appears to be missing 3 spire clips(?), though one was found on the speaker magnet ... you may be able to see it in the photo.

Many thanks to Mike (cobaltblue) for pointers/links, much appreciated

Mark

[electronicskip]

Good luck with yours also.
Your Cossor looks to have the 2 colour dial glass which differs from mine.
Nice set.

[MurphyNut]

I'm in the market for one of these, but that "plastic surround" is problematic for me, they have always either shrunk or broke and I don't like the way you can see distortions showing were the surround attaches to the main cabinet. It's a shame this cheapens the look of an otherwise nice looking radio.
I think I'll keep looking for the rarer 494, without that surround, it makes you wonder why they redesigned the set to have this troublesome part when it was far more simple and nicer looking in the first place.

[Cobaltblue]

I sort of assumed since so far I have seen no documents that explain the change that it was a simple face lift for a tired looking model.

It also allowed the wooden cased 500 to have the same family resemblance.
The later model allows the scale and speaker opening to be better balanced and slightly bigger.

I don't mind the look of either configuration

I sort of prefer the 494 since it's the origins of the model.

However I am fond of the whole family.

Cheers

Mike T

[mark2collection]

Originally Posted by electronicskip

Your Cossor looks to have the 2 colour dial glass which differs from mine.

It has, mines red & an off white, your set appears to use Loctal valves, where as mine has Rimlok. Also, your HT cap is mounted behind the aerial sockets, mine has the opening, with my cap mid-chassis, towards the front.

Your mains transformer is mounted the opposite way to mine ...

Amazing the differences over the production run.

All the best,

Mark

[mark2collection]

Originally Posted by MurphyNut

I'm in the market for one of these, but that "plastic surround" is problematic for me, they have always either shrunk or broke and I don't like the way you can see distortions showing were the surround attaches to the main cabinet.

It appears to be quite a soft, thin bit of trim on my set, I wonder when the distortions/shrinkage began on these?

I guess a lot depends on storage, as technology/fashion changed, sets then being passed between family members, an awful lot must have ended up in less than favorable storage conditions.

Mark