Wednesday, September 20, 2017




                                                            Repair of the Link AX Part 7

In June of 2017, we moved the Link AX into the shop and started work.   Most of the detailed work is now finished and reassembly started.

You may remember that in our first check, we found that the soft pedal system interfered with the repositioned drum and we left that problem for later.   When we reinstalled the xylophone, we saw the basic problem was that the units were very tight against the case.   I now think that the repositioning of the drum assembly was a factory job or that perhaps the drum assembly was from a different instrument.   At any rate, there is very little room to spare, so we bent the soft pedal bracket to clear the drums.


When we loaded the paper roll, we found the reason the previous roll was so badly edge damaged.   The guides were narrower that the paper.   We repositioned them to give the paper clearance.  The drag plate was warped and did not sit evenly on top of the paper.   We bent it until it fit properly.


The v-belt pullet was installed on the motor and we now have a v-flat drive for the pumps.


There are a few cosmetic items to take care of; but we are about done with this job and all the functions now work.

Wednesday, September 13, 2017

                                                               Climate Control

When Jake had the collection on Route 8, South of Franklin, the building had no climate control.   A  lot of condensation happened when the conditions were right for it and thus many of the metal parts of the instruments show a degree of rust.

The old G.C. Murphy building, which is our present location, had steam heat and added an A/C system in the 1960s.   We had to replace both of them with a combined roof top unit.

We have done our best to reduce unintended air leakage, but we still have a humidity control issue.   We want about 50% relative humidity, so in the absence of a big humidifier in the winter months, we keep the temperature at 50 degrees and humidify selected machines that show sensitivity.

Summer humidity in the basement required 4 dehumidifiers running full time to get to 50%.   Further investigation found that the foundation was stone cemented in place.   A pegboard  covering with no vapor barrier was exposed.   We started a project to put a vapor barrier in place behind the pegboard to prevent moisture entry.   Over the last 4 years, we have done this in pieces, while also adding base plugs in selected areas while we had the peg board down.   The last 150 feet of the barrier was added this past winter.   While doing this, we found several direct air leaks, which we sealed.  



This picture shows the stone foundation wall, a portion of the vapor barrier and the pegboard cover.

Our success is demonstrated by the fact that we now need only 2 dehumidifiers, one running part time, to consistently maintain the desired 50% humidity.

Aside from the humidity control, this saves us about $20 per month on the electric bill.

Wednesday, September 6, 2017




                                                REPAIR OF THE LINK AX Part 6


In June of 2017, we moved it into the shop and started work.   Most of the detailed work is now finished and reassembly started.

You may remember that in our first check, we found the soft pedal system interfered with the repositioned drum and we left that problem for later.

The first problem we found was that both the on and off tracker holes were plugged.   That seemed an easy fix; but unplugging them fixed nothing.   So we started at the valves in the bottom leftside and traced hoses.


The #1 hose was plugged someplace, so we started tracing it.   The routing took it behind the valve area.   It was stuck and could not be moved.   Using the air compressor blew a hold someplace.


Pulling would not move it, so we decided to replace it.   Disconnecting from the tracker bar we followed it through the hose bundle on the right side of the case.


We replaced the line from the tracker bar to the valve.   A check showed all was well.   A later check showed it was still plugged, which meant the tracker bar had redeveloped a problem.    Attempts  to clean the nipple yielded more chaff, but also pierced the tracker tube.   We had to solder up the hole.   We then reconnected the tubing and all is well again.





It took longer to do, than to tell the story.

Wednesday, August 30, 2017

                                                       


                                                              Repair of the Link AX Part 5


You remember that since the Link arrived from Jake's barn in 1994, it had been used on the first floor as part  of our guided tours.   Very little work had been done on it.   In June of 2017, we moved it into the shop and started work.   Most of the detailed work is now finished and reassembly started.

We made and installed a new mandolin rail, but the pneumatics and system was supposed to work; but would not function.

For the next few days, we traced hoses and fixed problems, such as the soft pedal that did not work, because the tracker was plugged.

Every few hours, I went back and tried to find out why the mandolin rail actuators did not work.
I emailed Paul Manganaro and he sent me a photo of the pneumatic actuator group.






At first I did not see the difference, but after some more looking and thinking, I realized that the one I was working with would hold the bar off, while the one Paul sent me, showed an assembly that would hold the bar.






During the last rebuild, someone put the locking bar on backwards.   Once you understand the problem, it is an easy fix.   To get to it, I had to take a few things apart, but in 45 minutes the problem was resolved.

Wednesday, August 23, 2017



                                                 REPAIR OF THE LINK AX     PART 4

You may remember that since the Link arrived from Jake's barn in 1994, it has been used on the first floor as part of our guided tours.    Very little work had been done on it.   In June of 2017, we moved it into the shop and started work on it.   Most of the detailed work has now been finished and reassembly started.

When the tambourine was put in place, we discovered one reason it had been damaged.   The paper music shelf had sagged over time and was actually sitting on top of it.   The question was what to do about it.





I decided to build a support on the tambourine mount to support the shelf high enough to clear the action.   It needed about 3/8 of an inch.

Having cleared that problem, it was time to put the back of the case on .   At some prior time, it looks like the cover had been flipped over and torn off the right corner of the back panel.   It had been glued back, but the alignment was off; with result being that the corner was too high.   The glued joint seemed solid, so we cut the corner down to match the rest of the top.

Probably as part of the incidence, some incorrect hinges were installed, ending up with 3 different sets for the 3 hinges involved.   We just took them off and will try to find a set of approximately original dimensions.   At least we will have them all the same.

The mandolin rail was discarded at some past time, so we will make a replacement.   The pneumatic controls are still in place, so all we need is the rail itself.   We have one which will be adapted; but more about that later.



Wednesday, August 16, 2017

                                                REPAIR OF THE LINK AX PART 3

You may remember that since the Link arrived from Jake's barn in 1994, it has been used on the first floor as part of our guided tours.   Very little work had been done on it; but it became increasingly apparent that it could use a little maintenance.   On June of 2017, we moved it into the shop and started to work on it.





The pump drive on the links was by a flat belt.   The motor pulley is 2 inches in diameter.   Jake had substituted a v belt turned inside out for the flat belt, which had been working since we got the instrument.




The belt was showing age and full of cracks.   We also suspected it of slipping on the drive pulley.   I know it is not original, but I decided to change to a v flat drive.   That meant a 2.25 OD v pulley to get the pitch diameter of 2 inches.   The moor has a .375 shaft and 2 1/4 pulleys all have 1/2 inch bores, so we had to get a reducing sleeve for the new pulley.

At some point, we realized that the motor leads were bad.    If you wiggled the leads the motor would stop.    A trip to our local motor repair shop, where as DeBence supporters they do small jobs for us a no charge, resulted in a motor cleaning and new leads.

Wednesday, August 9, 2017

                                                            Repair of the Link AX Part 2

You remember that since the Link arrived from Jake's barn in 1994, it has been used on the first floor as part of our guided tours.   Very little work has been done on it, but it has become increasingly apparent that it could use a little maintenance.   On June of 2017, we moved it into the shop and started work.




The tambourine had shown some playing problems, so we looked it over.   The basic mounting was in trouble.   The lower support pin had fallen out, letting the upper pin take all the shaking load and it had worked loose while stripping the screw threads.



The hole was now so big that even an oversize screw would not work, so epoxy was used to hold the upper support screw in place.




Beyond that the next level support had split and had been repaired by adding screws to hold it together.   I cut off the split area and glued a new piece of oak in its place.



The wood nuts on the shaker link were rusted in place and also brittle, so they were removed and the threads wire brushed to clean them up.   Then it was reinstalled.