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Westrex BRPE paper tape punch 110 chars/sec

Started by charliecoutas, Jun 14, 2024, 07:39 AM

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charliecoutas

In the Very Unlikely Event that a forum member ever needs to interface with a fast paper tape punch, made by Teletype, I have just got a driver board working and would be happy to give you a blank pcb. I use FreePCB and they always make 8 or 10 boards and I only need one. It uses an 18F26K22.

Charlie

JonW

#1
Sounds a cool project Charlie.  I found a cool video showing how these paper punches and readers work, fascinating how fast they punching and reading

https://youtu.be/fA42KVVcXA8?si=nFOTH20wFMoKZB9M

charliecoutas

This one is quite a bit faster than the video you refer to. The mechanism is rotating 100 times every second and the electromagnets pull in in 4mS and release in about 5mS. It is quite a fearsome machine and I am careful not to get my fingers too near while it is running.

We will use it at the museum to prepare paper tapes for Colossus, they are about 5800 characters long.

What fun.

Charlie

JonW

That sounds awesome, you should have a machine where you can type your name and print it off for a few £ and make some money off it


See_Mos

Sounds interesting Charlie.

My last employment involved repairing old CNC machines that still used punched paper tape for programming.  Over time the sync holes became stretched causing malfunction.  I always wanted to replace the tape reader with a PIC and SD card but the end user wouldn't spend the money even though it would have saved money and loss of production caused by downtime.

kcsl

Charlie, do you know of a source for blank paper tape ?

Regards,
Joe
There's no room for optimism in software or hardware engineering.

JohnB

We married back in 1970, I had an Austin Healy Sprite, when we drove off from the reception it had been filled and I mean filled with paper tape. Even the heater had been filled with chards, never got rid of the stuff.

About 8 years ago I had to clear our loft and found a paper tape writer and reader and rolls of blank tape.  The reader was entirely mechanical with sprung prongs sensing the holes in the paper tape.  Should have offered it to the National Museum of Computing, instead I offered it to a local school.  Not sure if it even got shown.
JohnB

charliecoutas

A source of paper tape? What a good question. Although I work at the National Museum of Computing I never thought about that. I suppose we have a stash of it but I must find out how much. Now that we can punch at 100 chars per second we may well have a problem in the future. I'll check in a couple of weeks time: we are having the asbestos roof on our gallery replaced and we're not allowed to play with our toys.

Charlie

JonW

I'm not sure what the weight of the original paper tape is, but quite a few companies are now making paper banding tape to replace single-use plastics in packaging.
Paper Banding

kcsl

Quote from: JonW on Jun 17, 2024, 08:53 AMI'm not sure what the weight of the original paper tape is, but quite a few companies are now making paper banding tape to replace single-use plastics in packaging.
Paper Banding

Well that's interesting. My machine needs 25mm, and they do 30mm. I wonder if I could make a machine that trims the paper width.

Not sure if they are a manufacturer or just distributer, but I'm going to drop them an Email to see if they can supply 25mm.
Failing that, one of my punch/readers needs some attention and I could possibly make a modified paper guide assembly that could accept the wider paper.
In the mean time, I've ordered a roll to see how it performs.
There's no room for optimism in software or hardware engineering.

RGV250

QuoteNot sure if they are a manufacturer or just distributer,
Says on the home page they bulk buy from overseas so sound like a distributor.

Bob

JonW


charliecoutas

Thanks JonW, that looks possible. The stuff we use is 17.5mm wide and our group have made a cutter that can cut the tape to make a narrower version - used by the undulators for printing RTTY as an inked trace on tape.


charliecoutas

25mm is for 8 track paper tape, we have 5 track. I don't know yet how much we have in stock. I'll have a poke around next week and see. This week the Colossus and Tunny galleries are being treated to new roofs, so we are not allowed in.

But thanks for the helpful suggestions and ideas, very much appreciated.

Charlie

kcsl

The 30mm banding tape arrived and I got a chance to have a play with it last night.
My original tape is 0.15mm thick, the banding tape is 0.14mm (according to my digital callipers which aren't the best).

I cut a section of tape down to 25mm using a pair of scissors which is crude, but the machine happily accepted and punched it.
It has the same opacity as the original and the machine read back the tape ok.
I need to do a proper test on a decent length of tape (the 4 feet or so I cut down isn't really a decent test).

The tape lengths are slightly shorter but that's not really a problem. The big pain is the centre plastic core is smaller than the ones on the original tape spools. I've got some original empty cores (or I can always 3D print some) so I can re-wind onto them, but considering the lack of availability of original tape and the cheapness of a spool of banding tape, it's worth the effort.

I'm going to try and find a UK source for 25mm tape, but I think this is a good alternative.
Joe
There's no room for optimism in software or hardware engineering.

charliecoutas

Thanks Joe, that's interesting. I was at the museum yesterday and asked a pal there who knows about stock levels, and the answer to "Have we got stock of 5 channel paper tape (17.5mm wide)?" The answer was "Yes, we've got loads."

He then showed me a cupboard with about six full rolls of white tape and a very sexy roll of black tape. I've seen white, pink, light green and light blue but never black. I'll put that roll on one side for when Les visits us and I demonstrate the punch (driven by an 18F26K22 of course!) to him.

I'll do a video of it working next week and post it on the forum. It would have been this week but the motor start capacitor decided that 50 years was long enough and became an open-circuit-in-a-can.

Charlie

charliecoutas

I have a .MOV movie of the punch running. How do I paste it in here?

Charlie

John Drew

Quote from: charliecoutas on Jul 08, 2024, 12:43 PMI have a .MOV movie of the punch running. How do I paste it in here?

Charlie
Another way is to put it on YouTube and place a link.
Cheers
John

charliecoutas

Thanks John, I'll have a look when I get home.

charliecoutas

I think I now have a YouTube movie of the punch working. Thanks John.

https://www.youtube.com/shorts/q9anFAGVQTI