Renewing an Old Typewriter Platen

I enjoy rebuilding old typewriters.  I like the challenge of taking something that is 50-100 years old and giving it new life.  One of the challenges in rebuilding an old typewriter is that you can't just log onto the internet and order new parts, since the typewriter industry pretty much died when pc's came on the scene.  So, you either have to cannibalize parts from another old machine, or make them yourself.

One part that you can pretty much never find is a replacement platen.  The rubber on a lot of these old machines dries out and hardens over time, and can develop cracks such as the one in the photo.  This typewriter was made by Remington in 1895, and is one of my current projects.

I won't delve into the details of all the work that has gone into this project -- instead I will focus on how I renewed this old cracked platen.

Step 1: Remove and Measure the Platen

Removing the platen on this old machine was relatively easy.  I removed the knobs on each end, flipped the carriage up (it is an old up-strike machine), and carefully removed the platen assembly.  The first photo shows the platen after removing the knobs and the second photo shows the carriage after the platen came free.

The next step involved carefully measuring the diameter of the platen.  I picked a spot where the rubber was still intact and used a caliper to measure  the diameter.

Step 2: Get the Old Rubber Off of the Core

Using a screwdriver, I carefully prized away the old, hardened rubber.  After removing about half of it, I was able to slip the rest off the end.  Next, I lightly sanded the wooden core, then measured its diameter with the calipers. 

In recovering a platen you pretty much have two choices.  You can try to find an industrial platen rebuilding service and, if they're willing to tackle your job it will cost you roughly $150 -- assuming they have recovering material in the size you need.  This is too pricy for me.

The 2nd choice is to recover it yourself with a piece of smooth rubber hose.  I have had success with this before on small diameter platens, but no one makes a smooth rubber hose in the size I needed. 

So......I decided I needed a 3rd choice.

Step 3: Jumping in With Both Feet -- the 3rd Choice

I decided to reline it with large diameter heat-shrink tubing!  I couldn't find tubing of the diameter I needed locally, but fortunately the internet came to the rescue.

I bought a length of 2" diameter heat-shrink tubing and began the process of building up layers.

Step 4: Building Up the Layers

I cut the first piece of heat-shrink tubing (adding an extra inch in length) and used a heat gun (1st photo) to shrink it to fit the diameter of the core. 

Once it was fitting tightly (2nd photo), I trimmed the ends with a shop knife.  I continued putting layers of the material on the platen and shrinking and trimming them until I had built up to the diameter I needed (this one took 5 layers).  The finished product is in the 3rd photo.

Step 5: Putting It Back Together

Re-installing the platen basically involved doing the initial step in reverse order.  This was the final step in bringing this 118 year old typewriter back to life.  I won't guarantee that it will last another 118 years, but you never know.....

Comments

[bernomaha49]

I own a 1920's Underwood No.5 typewriter, and I cannot afford to have its platen recovered with rubber by J. J. Short. I am curious as to whether or not you still have the typewriter, and if so, how well has the shrink-wrap covered platen held up over the past ten years?

[knife141]

It has held up very well.

[edmundbarber]

I have a type writer and I like to write stories on it and I write to my grandad!

[Art Mecho]

Thanks for the info...I've tried various things..but yours sounds best unless you get new platen rubber. One thing Ive done in a puin ch..just to get the typer going (Erika Klapp..paper slipping)..is to use a special "tape" made by 3M..(got it al antique machinery show)..called Linerless Rubber splicing tape..it's 1.5 inches wide and about 2" wide also..It's maybe 1/32 thick and has quality adhesive on one side. I covered the old platen rubber with a few "rings" of this...it's not the greatest looking (i cut it real carefully...overlapped at the end a razor cut)...but it worked..it's a bit soft...but works fine.It's for wrapping splices on power lines and electric lines....handy stuff.

About ribbon reviver....I have had remarkable results using three products..all similar (1) DG lube spray(a cheap version of PB Blaster they sell for $2 at the Dollar General store)...brush it on ribbon as you wind it one way..try to use just enough to wet the ribbon...do whole thing and wind back w dry brush spreading it even. (2) PB Blaster penetrating oil, (3) Sea Foam fuel injector cleaner.....use all three the same way...I've DG'd about ten ribbons...it's a bit sloppy and wet at first....either you can hang ribbon to dry..or leave it a few days or week...about 3/4 ribbons work VERY nice after that.......Sea Foam is the best fuel injector cleaner I've ever used BTW

[crazyg]

as i was reading , was not expecting a wooden core. then you supprised me with heat shrink. i was thinking theres going to be a seam somewhere. great sidestep manouver. does it have the voltage rating printed on it. municipal aesthetic. and can you get a choice of colours like smaller shrinks . interested to see how the rubberyness compairs to stock .

[panamapjs]

Not bad--how does it type? The key to platens is the hardness of the rubber. JJ Short Associaties will recoat and most platens end up under $100 including shipping. This Remington would be $ 60 plus shipping and you get the right rubber and the right diameter.

[throughmyeyesdesigns]

Very industrious

[shizumadrive]

Very nice. I'd love to see a group of instructables tied together to fix the common issues with old or abandoned typewriters. Including a way to reink the ribbons. I'm sure there is a way but havent looked it up.

[StephenC2]

I use stamp ink. It works a treat. The trick is just to not put too much on.

[knife141]

I've read about people re-inking ribbons using stamp pad ink, but I've never tried it myself. Most ribbons are still available on the internet. Since I rebuild a lot of typewriters, I buy universal ribbons in bulk (a dozen at a time). If a universal ribbon spool doesn't fit a particular machine, I rewind the new ribbon onto the old spool. If the old spool is missing and a universal spool doesn't fit, I make/modify a spool to fit it. Thank you for your comment.

[jackzylkin]

This is a fantastic instructable -- great job! Do you have a link for where to buy the heat-shrink tubing?

[PecanCorner]

This is brilliant. I can't think of any reason for this not to work effectively for at least 50 years. Thank you for helping keep these great machines alive!

[knife141]

Thanks for the kind words. The built-up cover feels strong and solid with just enough "give" to it. I think it's going to hold up judt fine. I've used heat shrink tubing to reline pinch rollers and feed rollers before, but this is the first time I've used it on a platen.

[chammen]

I would be curious to see the process you went through to repair the pinch or feed rollers. I have a 1919 Underwood that belonged to my great grandmother. These rollers have hardened and stuck to the platen. I think the platen can be smoothed out, but the rollers under the feed are beyond basic smoothing and would require this sort of buildup. I am considering sanding them down and trying some shrink material like you mention in this Instructable.

[orrinson6]

VERY cool!

[micah1_8]

I wonder if plastidip would work as well.

[ironsmiter]

consider building up with inner tube material, and heat-shrinking over that?
Should restore the 'bounce' a bit better than straight heat shrink layers.

Nice work keeping old-iron alive.

Alternatively, try shopping with the enemy!
I've got a small collection of rubber coated rollers out of computer printers that are close to that diameter.
Match the diameter, and width, and what's left is transferring the gear to your new printerplanten.

[knife141]

I thought the same thing about inner tube material until I looked at one. It had a very pronounced seam that I was afraid would distort the heat shrink material (and leave a horizontal line). Using a printer roller (assuming one the right size) might work, however I think it would be quite a challenge to transfer the platen clutch to the inside of one. Thanks for the comment!

[ironsmiter]

AH! didn't know there was a clutch in there.
You probably have the easier technique with the shrink tubing.


The inner tube ridges CAN be sanded down, when the tube is inflated, or stretched tight(turn inside out when done, to remove possible ridges INSIDE also, so you get a really smooth tube). IF you decide to TRY it one of these days, I would actually recommend cutting the rubber into long strips, and spiral winding onto the drum. This way, if your knife is sharp, and your cuts straight, you can cut the ridges out entirely, and the butted joints should be smooth and invisible once the outer layer of shrink tubing is on.

Again, great job keeping old iron alive(and helping others do the same).

[grandmaof13]

Your instructable is interesting and informative. I also checked out your one on repairing an old typewriter. Very good instructions. I plan to have my husband look at it. I picked up an Oliver number 3 at an auction for $5.
. The case looks pretty good. The keys are really dirty and stuck. Hoping my husband can use your work to do some good on this one. Thanks for the instructions.