.: Rubber Drive Belt Measuring Help :.
You should only be here if your belt was NOT found in our our "find my player" tool, or the results there give you cause for pause. A new belt xref is tedious. We lose $ on new cross references and we lose a lot of money if we have to try a 2nd or third belt. Our only hope to recoup our losses is to be as efficient as possible so we can make a few bucks if the new xref helps a future customer to immediately choose the right belt using the website.
So when we work with you to develop a new xref we must be efficient for both our sakes. We hope to make money the next time and you get your player up n running in one shot. We cannot use vague language such as "well it's still pretty tight" or "well it sags about a 1/4 inch" or our favorite "well I found three pieces in the bottom of the player and the total length of the pieces is xyz". Wow talk about a master disaster!
To get this right fast we must cut to the chase. Wait, no, don't cut your old belt; we don't care. That's right we don't care about it's length. We only want its thickness and/or width and a string measurement around the pulleys. Let's continue; first we must all be on the same page but before we even get started, NEVER-EVER rely on "aye-eye" to tell you (or relay to us) a belt size to buy. The belt size journey is both too simple and too complex for "aye-eye". All it can do is regurgitate internet info and if that info is wrong or it tries to extrapolate similar data, well, you know.
.: How we measure and think about *NEW* belts :.
1) FIRST & FOREMOST: All *new* belts are listed/spoken/thought of in terms of the total length/circumference (as if it were cut and laid straight). NEVER the diameter across an elusive 'circle':
Above does NOT mean we want you to pinch or cut your old belt and tell us the measurement. This is a decades old method that is prone to error because we don't know if the belt stretched a lot or a little over the decades. So this concept is only presented above so we are all thinking about NEW belts in the same manner. We have received numerous returns because "why is my belt 3x longer than what I ordered?". It's because Pi 3.14. Our part # system reflects total circumference not diameter so when you see a belt stock # on our site such as FBM9.9 it is 9.9 inches in circumference.
2) Please use English measurement system if reasonably possible for you. Or at least stay consistent. Don't mix systems when telling us length X thickness.
Length Converter
Now that we are on the same page, let's continue.
.: How to get us an accurate drive belt length measurement :.
****Best Practice Method****
- Thread non-stretchable string (NOT YARN) around all the pulleys of the entire belt path, including the motor drive pulley. You may need to use a little tape to hold the string in place. Taking extra time to do this gives us a solid length, from which we can develop an accurate belt cross reference for you so you can get the right belt the 1st time. We highly prefer this method over getting a length measurement of your old belt as we don't really know if your old belt stretched a lot or a little over the decades. Other vendors are still using the last resort method below as their first method.
- Then mark the string with a felt marker where the two ends meet.
- Then measure the total length of the string between the marks.
****Extreme Last Resort Method****
We almost want to remove this section, it's not an option just skip it. We only care about old belt length if you have arthritis etc or sometimes if you have a Nakamichi, Empire or some other finicky mechanism, then it may be of some help to consider in addition to a string measurement. If string is absolutely not threadable around belt path, which is rare, and you have no choice but to provide the length of the old stretched out unbroken belt please provide the length of the belt pinched and pulled just enough to be straight and not beyond. We will 2x that length. If your belt is broken/cut, we seek the total relaxed current length. Make absolutely sure you have the entire belt such that there is no other small segment you missed in the machine. This method is deemed last resort because belts stretch at various rates over the decades so we don't want to chase a moving target.****Applicable to Both Methods****
- IMPORTANT: When you email us the measurements, you *must clearly specify* if the length provided is "relaxed belt length" or "string length" as we need to know if the number is ballpark (rubber) or accurate (exact belt path) and so we don't wonder if you have already subtracted the industry standard of 3-5% for a new belt; we need to know.
- Provide the make/model of the player. We don't need the serial number.
- We also need to know if your belt was round, flat or square in it's cross section, as well as the thickness and if it's flat, the width as well. See image at top of this page for clarification. If your old belt is missing or melted then a "C" or half moon shaped pulley track means you had a round belt, a V shaped pulley track means the belt was square, and a flat flywheel or wine barrel shaped motor pulley means the belt was flat.
- this chart may help approximate thickness if you don't have calipers or a micrometer.
- US dime = 0.052 inches / 1.3208mm
- US penny = 0.062 inches / 1.5748mm
- US quarter = 0.066 inches / 1.6764mm
- US nickel = 0.080 inches / 2.032mm
- US half dollar = 0.084 inches / 2.1336mm
With the above info, we can assist you in choosing a belt about 3-5% shorter than the length of your actual belt path, which is the industry standard to provide correct tension, torque and playback without excess strain on your motor pulley. EXAMPLE: You measure 25" on your turntable with a string.....we will recommend a 23.6" belt, NOT a 25" belt as there must be some tension for your belt to work. Also, if you multiply your string length by 0.95 and 0.97 then you can find a replacement yourself by size description. Or if you prefer, just >>> email us <<< all the above info you have gathered. All belts are sold with a free exchange policy. For unlisted/new cross references that you reasonably provide the above requested info, we will not charge you any extra fees to exchange belt sizes for you. Belts must be returned in resalable condition and we ask that you inform us of the final belt that worked for your specific model so we can update our site to better serve future fellow owners of your model.
