| Info on Bodine & Other Fractional HP Motors |
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Partial update 07/31/2009 1120 hrs Z
There have been a number of motors Fractional HP, Synchronous, Hysteresis used on units throughout the manufacturing life-cycle of many turntables, some of these same style/type motors were used on competitive units: Russco, QRK, Gates/Harris, Collins, Sparta, Spotmaster (Broadcast Electronics Inc.) Presto, ROK, Micro-Trak 720 & 740 series, LPB and others. The JPEG's below are a small part of the styles used and as such this list is by no means complete. Often, during the natural progression of up-grading turntables or introducing a new model or style, 4-6 motor-types from different electric motor builders were tried for a period of time, disregarded for a "different", (not always better), "more reliable", RPM stability or most often, the BIG reason, COST per unit!
This "changing-out" of motor manufactures or styles was not always due to the motor in question not being able to do the job, more often it was the "cost-factor" which raised the proverbial bean-counters eye-brows of "XYZ spin-it-up" company. In "Company-speak", straight talk, design innovations, tooling, profit margin vs sales, cost of motor vs per-hour run-time, over-all life-span, care and maintenance (or lack-of). This statement held merit when U.S. made motors were up against the "less expensive" Japanese designed motor. Builders were required to purchase in bulk, the smaller Japanese electric motor was coming into it's own, competition and "branding" at it's finest. Many turntable builders turned their sites (and monies) to the overseas motor builders, many of the "non U.S." import motors were good, (if not great) less cost per unit than U.S. made electrics, just as importantly, they performed well! The U.S companies were pricing themselves out of the turntable motor business, smaller imported sealed bearing motors that were of good quality were on their way. Non-U.S. imports were setting new standards, raising benchmarks that the U.S. builders had to meet not the other-way-round as it had been for so many years. Idler drive and early belt-drive units and their "bulky" motors were being replaced with a new breed, Direct drive and their almost "clock-work" motors.
The pictures below are only to help you identify certain motors as well as to give some information concerning where "else" these motors were used. Just because the venerable NYC-12 was used extensively by Russco and other builders does not mean that the NYC-12 designation on the nameplate meant that particular unit was designed or "supposed" to be or "was" meant for that turntable. Bodine Electric Motors of this type were also used in large electric driven "town clocks" as well as being used in other situations where a "fractional horsepower" motor would fit-the-bill and could be serviced easily, if you will, maintained with little effort and give your equipment a reasonable life span. On a more positive note, these units when not maintained as per Bodine recommendations could be sent off to a qualified motor company and re-built from front bearing shaft to rear thrust bearing (if equipped) at a "then" reasonable cost, truly becoming a "new unit" lasting for many more years.
The statement above still holds true, if you have a Bodine unit that has given it's all, it can still be shipped off to a reputable shop or two and re-built as new, for a price! Most of the NYC-12's RTC has sent off cost $135.00 upwards of $300.00 to do a full-tilt re-build to a seriously damaged motor. The cost of a new "replacement" NYC-12 motor back in 1980 was $110.00- $150.00, the current price of re-manufactured/re-built Fractional HP turntable motors is not bad when you consider inflation rates and man-hours work on this work-horse (or should it be War-Horse). There are individual sellers among different auction houses where this type motor can be obtained, you may get a good deal, then again you are dealing with a 20-30 year-old unit at the very least! At this point you realize you have no clue of how the unit was run or maintained much less how much life-span there is left! We are talking DJ's here, not studio engineers!
LOOK at the last 15 or so JPEG's and you will get an idea of how motors should not be treated, this was a "good" buy for me some time back, (until it arrived), turned into a costly motor rebuild of $150.00, thankfully the windings were not smoked!
We have all seen these fractional HP motors sell for $90.00 on a good day and $135.00 or more when someone needed it now to fix their "baby". Frankly, seeing Russco's and other "like" tables getting sold for $175.00 and up (way-up) at auction is not so bad when you consider the cost of a quality re-build, especially if you are fortunate and acquire a good motor with your table. The JPEG's below deal with the Bodine NYC-12 in many of it's configurations, we will put up information concerning other motor units that can be/were used interchangeably among different turntables.
Note: different capstan combinations were used on these and other early turntable motor shafts. Many of these "stepped" capstans (whether single, 2, 3 or 4 steps) were of the slip-on type that slid-on to the main motor shaft, held in place with 1-4 small allen-head screws. The best of these in this particular configuration had 4 set-screws, 2 set on one side of the shaft and 2 more 180 degrees opposing. This was a "basic" set-up for attaching the idler drive capstan, it worked but did have it's own shortcomings. When aligning on a vertical axis so the face of each step was "face-aligned" with the idler wheel you needed to be careful when tightening the set screws which held the capstan to motor shaft. Even though the capstan was "held-tight" on the shaft this in no way meant the capstan was centered as related to the motor shaft. If one did not take time to assure the capstan had equal clearances all-round the shaft assembly where mated to the capstan an "off-set" was created bringing noise (wow & flutter) and a noticeable "bump" in the spinning of the capstan against the face of an idler. In the end, a motor/capstan that does not have proper face-to-face contact with the idler wheel assembly will cause slipping and speed variations.
Some variations on capstans occurred within the community, more expensive to machine yet worked well. Bodine and other builders would sometimes "cut" or "step" the Rotor assembly/ main shaft (if heavy with enough metal) resulting in much better tolerances vs slide-on capstans. This only worked well on small motors as long as you did not have to cut deeply into the main shaft thereby weakening it due to the lack of metal "meat" and constant pressure on this cut-down shaft.
A third way was also used when the motor shaft was a bit to small in diameter to cut into substantially. A number of three (3) speed units were stepped in two (2) steps on the main shaft thereby leaving enough strength to not bend the shaft when applying pressure over extended periods of time. They (motor-builders) took this a bit further (NIDEC) on their three-speed units by combining a two-step cut in the main shaft by slipping the larger capstan speed unit down over the first two steps to the base of the shaft thereby creating the third speed without compromising the strength and integrity of the main shaft.
As newer technology advanced in metal alloys a few companies were able to cut into the rotor shaft without loss of rigidity, strength and endurance.
A bit of "Basic" information on Motor Speeds:
The "Speed" of the turntable platter is a fixed constant. Speed is determined by the motor-speed, motor-capstan size and the platter inside dimensions especially where IDLER-DRIVEs are concerned.
On a standered 3 speed unit many people confuse the three small front panel plate set screws as speed adjustments. These are not! These are motor/idler torque adjustments and vary the platter start-up speed ONLY. Turntables can be set up to almost instant start with no overshoot in as little as 1/16 of a revolution (22.5 degrees) They can be over-adjusted as well causing a cued-up record to jump the grooves because of the massive start up "kick"; an interaction of motor and shock mounts along with tension spring or bow washer interaction. Speeds can be changed by altering the motor capstan size only. This requires either a new capstan if it is a slide-on / over shaft type or if capstan is cut into shaft a new shaft assembly from a qualified motor rebuilder/re-winder to re-cut / lathe-turn the shaft assembly. Many pressed-on capstans require a good machine shop to remove the old capstan, pressing-on a new billet capstan and cutting/turning to size in a pression cutter/lathe while running to insure correct diameter for the required speed/speeds
See some of the photo's below.
(Click a JPEG below to start slide-show)
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