A Roll-Repair Table
By John Phillips
Yesterday I finished a project I've been thinking about for years and have been actually doing something about for several months. It's a table for repairing 88n piano rolls. It looks like a little wooden coffee table about 18" (45 cm) long with legs about 5" (12 cm) high. It's a few cm wider than a piano roll and has a flat chipboard top with rounded ends. There is a sheet metal housing screwed to each end of the table. One end contains the spring loaded chuck and the drive chuck for a roll. These were salvaged from a discarded spoolbox found on our local garbage tip by a friend. (His find provided the impetus to get this project going.) The housing at the other end contains the take-up spool from the same spoolbox. Crank handles on the drive chuck shaft and the central shaft of the take-up spool enable the roll under repair to be moved back and forth.
So far this sounds like any old repair rig but wait, folks, there's more!
Often, when repairing a roll, one comes across a section where some (supply your own adjective here) person has applied sticky tape to the underside of the paper, or where the paper is so badly folded and torn that access to the underside is necessary. This outfit makes that possible; so far I've only described half of it.
The bearings for the shaft of the take-up spool are two brass disks, about an inch in diameter and a quarter of an inch thick. The shaft fits through holes drilled in the centres of the disks. Each disk has a shallow trough turned in the middle of its rim.
The sheet metal housing at the take-up end has two vertical U-shaped cutouts, into which the brass disks' shallow troughs just fit. This means that the take-up spool can be lifted up out of the housing at any time. When I want to get at the underside of a roll I clip a second "coffee table" with shorter legs to the music roll end of the first table. This second table has a metal housing with U-shaped slots at its far end. All I have to do is lift the take-up spool out of its usual position, move it up and over in a wide arc and fit it into the second set of cutouts. Hey presto! The roll is now lying underside up on the second table surface.
Why does the second table have shorter legs than the first? Because the paper is now unwinding from the bottom of the roll rather than the top.
I haven't written all this just to show off, although that was the major reason. I do have a serious question about repair technique. The most common damage to piano rolls, as we all know, is little rips along the edges. I use Filmoplast P tape for almost all my repairs and do edge repairs by cutting the tape into short lengths and transferring it bit by bit to just inside the edge of the paper, using a length of springy wire set into a short length of wooden dowell. This enables each piece of tape to be placed quite accurately but is extremely time consuming.
In an exchange of emails with Terry Smythe months ago, I got the impression that he puts the tape on so that it overlaps the paper edge and then slices along the edge with a steel rule and a scalpel. (I hope I'm not misrepresenting you, Terry?) This would be very much quicker but I have these worries about doing this.
1) There is a danger of cutting roll paper away. (So be very careful, I suppose?)
2) Because tape adhesive goes right up to, and maybe overlaps the edge sometimes, there is a danger that successive turns of the rolled up roll will stick to each other.
Number two really worries me, because I make my own bridging tape from Filmoplast P, to repair places where the original chaining has pulled apart. Even though I always rub talcum powder into any exposed adhesive on the underside of the bridging tape, if a repaired roll is played after a few months, it is possible to hear the bridging tape un-sticking itself from the next layer of paper as the roll unwinds. So far this has caused no trouble, other than mental distress, but I can envisage a real disaster if the edges of a repaired roll become glued together.
If anybody has any comments about roll repair techniques before I start on my huge backlog of damaged rolls, I'd be very interested to hear them.
Merry Christmas, everybody. John Phillips.
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(Message sent Thu 19 Dec 1996, 02:35:48 GMT, from time zone GMT+1100.) |
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