1 - reakeener1970
- Novice Typer
Offline - Registered: 17-2-2016
- Posts: 28
For the love of God!! How is platen recovered???
Hi,
Does anyone have any info, links, photos, video of just what / how a company that replaces rubber platen does?!?
I have searched everywhere to find something. Basically, I want to know how a company like JJ Short actually replaces a platen. Are there rubber tubes lying around that are cut to length? Does it have to be lathed to the right size? What kind of rubber? Where does it come from? Are there unicorns involved?
I do NOT need links to videos of putting bicycle innertubes over old platens.
I want to know (and preferably see) how it has been done in the real world for over a century. And I can't find a darn thing online and have been searching on and off for weeks.
Thanks!
p.s. and yes I know JJ short is the last place to get it done now but HOW do they freaking do it?
- ztyper
- Key Master
Offline
- From: Somewhere in New Jersey
- Registered: 01-10-2014
- Posts: 773
Re: For the love of God!! How is platen recovered???
I'm not sure how. It's a specialty thing that only a company like JJ Short does. Why not ask them?
A high schooler with a lot of typewriters. That's pretty much about it.
- thetypewriterman
- Key Master
Offline
- From: Leiston, England
- Registered: 29-5-2013
- Posts: 897
Re: For the love of God!! How is platen recovered???
The firm will have a stock of pre-molded rubber tubes, usually around 92 shore hardness. They may have pre-moulded them themselves or got them from a specialist outside supplier. The old platen is heated in an autoclave to soften the old rubber, which is then manually stripped from the core. The core is then cleaned and a new sleeve cut from a length of tube is pressed on. Adhesive may be used if necessary. The core is accurately mounted between centres on a special machine which resembles a lathe. The bed and centres move from side to side whilst the cutting is done by a rotating grindwheel. The outside is then ground down to the finished diameter. Practically impossible to do at home 
- Spazmelda
- Key Master
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- From: Ohio
- Registered: 25-2-2015
- Posts: 830
Re: For the love of God!! How is platen recovered???
thetypewriter man pretty much summed up my understanding of it. I was just going to say, I know they do grind them down. When I had my Blick done, we weren't sure of the OD for the platen and they told me to try it out and send it back if it needed further grinding to reduce the thickness.
- verhaden
- New Member
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- From: OH
- Registered: 17-2-2016
- Posts: 11
Re: For the love of God!! How is platen recovered???
I replaced the platen on one of my Lettera 32's. Typewriter Database says it should be 32mm thick. I bought some A82 Shore neoprene tubing with an OD of 1.25" to slide over the platen core. However, the ID of the tube was too big for the core (1" v. 0.9333" or so), and I had to buy heat shrink tubing to bulk up the core diameter. Ended up using two layers, but could have gone with three.
Worked out well enough. It's much quieter and the type impressions are a little richer. Cost of everything shipped was <$30.
Tried to source metric rubber tubing from Aliexpress and other foreign sites, but didn't have any luck finding anything comparable.
- SoucekFan
- Speed Champion
Offline
- From: United States
- Registered: 27-12-2015
- Posts: 480
Re: For the love of God!! How is platen recovered???
verhaden wrote:
Typewriter Database says it should be 32mm thick.
Where in the Typewriter Database were you able to find the platen measurement?
- verhaden
- New Member
Offline
- From: OH
- Registered: 17-2-2016
- Posts: 11
Re: For the love of God!! How is platen recovered???
Many models feature platen diameter at the top of their respective brand pages.
Olivetti Platen Diameter Model Diaspron 82, Lexikon Electric, Studio 44, M20, M40, Lexikon 80: 1.622" (41.2mm)
Model Studio 42: 1.429" (36.3mm)
Model MP1, Lettera 22: 1.259" (32mm)24
It actually doesn't list the measurement for the Lettera 32, but the listed diameter for the 22 matches.
- SoucekFan
- Speed Champion
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- From: United States
- Registered: 27-12-2015
- Posts: 480
Re: For the love of God!! How is platen recovered???
I can't believe I've never noticed that. Thanks.
- Uwe
- Moderator
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- From: Toronto, Canada
- Registered: 12-3-2013
- Posts: 4,408
Re: For the love of God!! How is platen recovered???
I can't believe I've never noticed that.
It's not included with every manufacturer's table, just the ones where the source for the serial number information listed such specifications. Regardless, not only would using an inexpensive digital caliper on your existing platen give you that information, it would also be a far more reliable measurement.
The pronoun I has always been capitalized in the English language for more than 700 years.
- SoucekFan
- Speed Champion
Offline
- From: United States
- Registered: 27-12-2015
- Posts: 480
Re: For the love of God!! How is platen recovered???
Regardless, not only would using an inexpensive digital caliper on your existing platen give you that information, it would also be a far more reliable measurement.
I do use a digital caliper, but when possible I like to double check against the original factory specs to compare, as some platens may have changed a touch over time due to age, refurbishing, and other factors.
