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Echolette pinch roller

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  • Echolette pinch roller

    I got a Klemt Echolette a couple months ago and found some Dynacord pinch rollers being sold on Ebay and was wondering if this would work on an Echolette. The dimensions of the pinch roller on my Echolette are
    20mm OD x 7mm ID x 12mm long


    Some more details:
    I used a dental mirror to look at the bridge rectifier and since its selenium (B 300 C 70) I decided to put in a silicon type bridge rectifier (KBPC50-10) to substitute for it. I checked the motor capacitor and two filter capacitors with an analog ohm meter and capacitor tester. The motor works (both speeds, bridge rectifier disconnected during the test). After that I connected the silicon bridge rectifier in place of the selenium (left in place but disconnected) with a 250 ohm power resistor in series with the new bridge rectifier. With a variac and ammeter connected, I slowly brought up the voltage and figured it looked OK. I tested the tubes with a tube tester and they look OK. I put the tubes in and turned it on with a microphone connected via a home made adapter with a 3 pin DIN connector and phone jack and connected the output to an amplifier. It worked with the mic connected, but there was no reverb. I connected a jumper between two pins of a 3 pin DIN connector plugged into the remote control and the reverb worked with some problems with the tape I can discuss later. It seems that it was a bad connection at one of the pots which I fixed. More recently I replaced the roller on the spring biased arm with a new polyurethane roller. It works good in the slow speed when I put my finger on the pinch roller arm and push it toward the capstan. If I had a new pinch roller it might work better.

    Also, I used a 9 pin tube adapter/tester (ie. Pomona) between the tube and socket and checked the grid and plate voltages on some of the tubes which seem OK. There doesn't seem to be any bad interstage capacitors (no shorts).

  • #2
    I found this on a foreign Ebay website

    As stated this is a rubber tape pinch roller for a Dynacord Vintage Echo Chamber Type S62 although I suspect it will fit other Dynacord Machines from the same era It is 22 mms diameter x 9.5 mms thick with a 5 mm bearing
    Looks like they aren't equivalent.

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    • #3
      You can have the original roller rebuilt with new rubber. I had two of them done last year by Terry in Michigan. Very nice work and fairly quick service as well.

      Where are you located?

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      • #4
        Some pictures of my Echolette. The roller on the spring biased arm was replaced with a polyurethane roller with a bearing.







        I'm in Maryland. If I had a new tire for the roller, I might be able to rebuild it myself. How much would it cost if Terry fixed it? There's some on Ebay (German seller) for about $60 a piece.

        Comment


        • #5
          Originally posted by Toynbee View Post
          I'm in Maryland. If I had a new tire for the roller, I might be able to rebuild it myself. How much would it cost if Terry fixed it? There's some on Ebay (German seller) for about $60 a piece.
          Here's the link www.terrysrubberrollers.com.

          The cost was $35 plus shipping ($6), but check with him.

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          • #6
            OK, thanks. Some pictures of the roller in my Echolette. It doesn't look that bad. It seems to be harder than a new pinch roller.
            Attached Files

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            • #7
              The center bearing looks to be serviceable, but there is a tape path indentation line along the outer surface. At least you don't seem to have a big dent in the roller from having the roller left in contact with the drive capstan.

              I'd try and clean up the surface of the roller first and see how the tape runs with just that much being done. Usually there are bigger issues to deal with that make the roller a last thing on my list. It's great to have the tape running smoothly, but if there is a problem with the electronics or the heads and there is no echo, that pretty much makes the roller a moot point.

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              • #8
                I tried googling "pinch roller refurb" and found some interesting links. I have some Rubber Renue and I'm going to try some more of that.
                one video I found:
                https://www.youtube.com/watch?v=nATgx4uJcZI

                Comment


                • #9
                  I tried putting some of that Rubber Renue on the pinch roller, but it doesn't seem to do much. I noticed there were some lines or deformations in the roller which caused some slight bulges on either end. I read a thread on another forum, I think it was at tapeheads.net about someone putting a pinch roller in a lathe and worked on the pinch roller somehow. I decided to try putting my pinch roller on a bolt (with a short piece of brass tubing as a shim) and putting it in the chuck of a drill press and filing the bulges on either end. It seemed to improve the performance when put back in the Echolette, but I still had to push the pinch roller arm toward the capstan to get it up to speed. I tried putting a second spring on the pinch roller arm before and that seems to work.
                  Attached Files

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                  • #10
                    If the last photo is the wheel after you have abraded it, you still have a few problems.

                    The shiny section is still going to slip because there is still a depression where the tape touches the roller. When the depression is gone, the entire surface of the roller will have a clean new even color.

                    I don't know what you are using to abrade the surface with, but it is tearing up the rubber. It should be clean and smooth or you will have tape speed problems caused by a too rough surface.

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                    • #11
                      That glazing is more obvious after filing the bulges. I used a jeweler's file. I was thinking of filing the glazing off where the tape contacts it, but I probabbly need to be careful with it.

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                      • #12
                        I bought 5 Neutrik Rean 3 pin DIN male connectors for $1.370 a piece recently from Allied Electronics. The price was lower than most Ebay sellers and they shipped it fast. They fit in the 3 pin jacks on the Echolette.

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                        • #13
                          This won't always work. Sometimes the rollers are just passed it and nothing but replacement will work. That said, I've used a fine emery cloth in the past. Apply slight pressure to the roller as it spins. Low and slow. Be patient. You need to take enough off the outside that the entire surface looks the same- no high or low spots and no shiny spots or grooves. Also, you'll need to continue to apply the Rubber Renue and let it soak in until it no longer does. Don't wipe it off right away. Let it do its job and soak overnight if necessary. If there's a chance of the pinch roller surviving, this will work. If it doesn't, time for a new one. My $.02.
                          Last edited by The Dude; 10-15-2019, 02:29 AM.
                          "Yeah, well, you know, that's just, like, your opinion, man."

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                          • #14
                            You need to use the DIN connectors for the two mic inputs and the footswitch connector, as the 3rd input that is recommended for instrument use and the output have already been changed to 1/4" phone jacks.

                            I don't know what sort of file you are using, but I suggest that the file be wide enough to cover the entire face of the rubber roller. In order to not distort the dimensions of the wheel, you need to try and remove the old rubber on the surface as evenly as possible.

                            I would also suggest that you file the surface flat before you use the Renue product.

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                            • #15
                              Be sure to send a photo of the final result. I think it should turn out an amazing thing!

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