Columbia Graphophone BI - Platter slows to a stop

[AaronDC]

Hi. My first post on this forum...

 

I just refurbed an our family's old Graphophone which hadn't worked for about 80 years! It's very exciting. It sat unused due to a missing bevel gear and repeater. I got a new bevel gear, cleaned everything up, greased and oiled springs and gears, replaced all the reproducer parts and got it working. However the platter slows down to a stop. It helps to lift up slightly on the arm. And, actually that was the situation right after I repaired it and now it barely spins when pushed. I used lithium grease for the two barrel springs -- I'm seeing that might be it. I ordered some clock grease from Ronell Clock. Am I on the right track here? Please share thoughts on other stuff to consider. Otherwise I can get to work taking the motor apart... which brings up my second question: I'm going to have to keep spinning that platter until that spring is fully unwound, correct? How will I know when it is done releasing tension? Thanks! Aaron

[phonogfp]

Aaron,

 

The problem of the turntable slowing can be caused by a number of conditions.  I'll start with the most common/most easily fixed and work down from there:

 

1) The mainsprings are not being wound enough.  Many newcomers fear breaking mainsprings by overwinding them.  As you know, a BI Disc Graphophone has two mainsprings, and you should expect to wind them at least 40 crank revolutions to play a single record.  With experience, a user will recognize when the mainsprings begin to offer serious resistance.  This will not harm healthy mainsprings.  Once the mainsprings are fully wound and the crank can no longer be moved is the point beyond which you should not proceed.  Until then, there's no cause for concern unless there's something wrong with the mainspring(s).  If that's the case, it (they) will probably break soon anyway.

 

2) The steel needle is not being replaced WITH EVERY RECORD.  21st-century humans often find this requirement absurd and will use the needle until their inexperienced ears suggest that it might be time for a new needle.  The fact is, acoustic-era records (pre-1925) were designed to shape the needle to their particular groove geometry by the use of abrasives mixed into the record material.  A dull needle being dragged through this abrasive exerts significant drag on the mechanism.  In addition, some Columbia records of the acoustic period are notorious for slowing/stopping the turntable - especially if worn.  Try several records.

 

3) The tone arm has not been lubricated.  It's important for the tone arm to be moving as freely as possible in vertical and lateral directions.

 

4) When you replaced the bevel gear, did you allow a tiny bit of play?  Tight gears rob power.

 

5) What's a "repeater" on a BI?

 

6) There are many, many, MANY opinions on the best lubricants to use on talking machine motors.  It's true that too much "stiction" or sliding resistance will severely decrease a mainspring's power.  Your idea of clock grease might be a good one as long as it's heavy enough.  Talking machine mainsprings are generally heavier than clock springs.  In general, we apply grease to mainsprings and the first gear(s) being driven from them.  Then, a quality (NO THREE-IN-ONE) mid-grade oil for the intermediate gears.  I use 30-weight automotive oil, but I've heard good things about Zoom Spout, Super Lube, and Lubit-8.  The governor needs good quality sewing machine oil on the shaft where the sliding collar moves, and on the felt/leather pads that limit the collar's outward travel.  I use Tri-Flow, which is formulated with PTFE., but any similar oil will do the job.  ALL BEARINGS NEED LUBE WITH A GOOD SEWING MACHINE OIL!

 

7) If the mainsprings on your BI were left wound for many years/decades, metal fatigue may have weakened them.  The only cure for that is replacement.

 

You shouldn't need to manually spin the turntable to bring the mainsprings to full rest.  Typically, the turntable acts as a flywheel when the motor is running, and will continue to relax the mainsprings even after they are at full rest - and this can sometimes cause the mainspring to detach from the arbor.  Experienced collectors usually don't allow their disc machines to fully wind down after use, but leave a bit of tension to keep the spring(s) in place.

 

I hope the foregoing will be of some help to you.  Good luck!

 

George P.