Using a 5L265 V-Belt as a drive belt substitute

gunner66 · Post by **gunner66** » Thu Jun 09, 2011 11:09 pm

SS is currently out of drive belts. I have read the pros and cons in numerous posts regarding using substitute 1/2" wide belts that were 26", 26 1/2" and 27" long (examples: 4L260, 4L265 and 4L270). As far as I can determine, the proprietary factory SS drive belt is 26.5" long (outer circle) and 9/16" wide (top width of belt), 7/16" (bottom width of belt), and 5/16" from top to bottom (height/thickness).

What about using a common 5L265 V-Belt? These measure = top width 21/32" x height/thickness 3/8" x outer circle 26.5"

I know that some rebuilders like Jacob Anderson are using 4L270 belts; and I also realize that the 4L265 belts are close to the factory size (e.g., Dayco V-belt Belt #17265 = 26.5" long x .53" wide), but - I was thinking that this 5L265 belt might work even better. Perhaps this size, being wider, would not tend to bind in the sheave fingers at the extreme fast or slow speed settings and thus be safer to use. I'm not sure, however, what other negative effects might come into play. I would be interested if anyone as tried a 5L265 size - or perhaps could offer any opinions +/- on using this belt size.

nuhobby · Post by **nuhobby** » Fri Jun 10, 2011 8:41 am

I don't know much about the industry-std sizes. But there is an e&ay seller who offers drive-belts for Shopsmith. I've heard they work fine.
I suspect -- and I'm seldom a conspiracy-theory type of guy -- that Shopsmith really has/had plenty of drive-belts if they've offered a bunch of rebuilt classic headstocks lately. This particular 'shortage' may be a way to push the PowerPro more and support the old headstock just a wee bit less.

billmayo · Post by **billmayo** » Fri Jun 10, 2011 10:47 am

[quote="gunner66"]SS is currently out of drive belts. I have read the pros and cons in numerous posts regarding using substitute 1/2" wide belts that were 26", 26 1/2" and 27" long (examples: 4L260, 4L265 and 4L270). As far as I can determine, the proprietary factory SS drive belt is 26.5" long (outer circle) and 9/16" wide (top width of belt), 7/16" (bottom width of belt), and 5/16" from top to bottom (height/thickness).

What about using a common 5L265 V-Belt? These measure = top width 21/32" x height/thickness 3/8" x outer circle 26.5"

I know that some rebuilders like Jacob Anderson are using 4L270 belts]

You would need a longer 5L belt to make up for the additional width. I am not sure you can get the full speed range with a 21/32" (5/8") V belt. I have been using the Kevlar K-Plus "A-25K " V-Belt (1/2"X27") for a few years. It allows me the speed range 750-5200 RPM that Shopsmith recommends. This V-belt appears to wear very well over time and not take a set like the regular V-belt when it is not used.

gunner66 · Post by **gunner66** » Fri Jun 10, 2011 1:57 pm

Please comment if these statements are correct or not:

1. If I had a v-belt that was the normal SS width (9/16"), but was a little longer (say 27" instead of the normal 26.5") - then the "SLOW" speed rpm would be a little faster, in that the belt would ride farther from the motor sheave axle.

2. When using the the 1/2" x 27" belt you have a trade-off going on, in that the longer 27" belt keeps the belt from going into the fingers of the idler sheave at the "FAST" setting that the narrower 1/2" belt would tend to do - but the the added length compensates for the narrower belt - even allowing for the factory speed ranges.

I suspect that the 1/2" x 27" belt tends to skew the RPM range to what is indicated on the speed dial in some minor direction - either up or down - as it seems no one would ever buy the single source and $$$ SS belts if the 1/2" x 27" was a perfect replacement.

Comments please?

dusty · Post by **dusty** » Fri Jun 10, 2011 2:07 pm

gunner66 wrote:Please comment if these statements are correct or not:

1. If I had a v-belt that was the normal SS width (9/16"), but was a little longer (say 27" instead of the normal 26.5") - then the "SLOW" speed rpm would be a little faster, in that the belt would ride farther from the motor sheave axle.

2. When using the the 1/2" x 27" belt you have a trade-off going on, in that the longer 27" belt keeps the belt from going into the fingers of the idler sheave at the "FAST" setting that the narrower 1/2" belt would tend to do - but the the added length compensates for the narrower belt - even allowing for the factory speed ranges.

I suspect that the 1/2" x 27" belt tends to skew the RPM range to what is indicated on the speed dial in some minor direction - either up or down - as it seems no one would ever buy the single source and $$$ SS belts if the 1/2" x 27" was a perfect replacement.

Comments please?

I have no experience operating with other than a standard Shopsmith belt BUT I would expect that the only changes would be in RPM at any given setting (slower).

Slower, IMHO, will not be a problem as long as you are in table saw mode. You can always dial up to a higher setting to achieve the higher RPM.

Jointing and shaping might be hindered because you can not reach the recommended RPM for these operations.

JPG · Post by **JPG** » Fri Jun 10, 2011 2:41 pm

gunner66 wrote:Please comment if these statements are correct or not:

1. If I had a v-belt that was the normal SS width (9/16"), but was a little longer (say 27" instead of the normal 26.5") - then the "SLOW" speed rpm would be a little faster, in that the belt would ride farther from the motor sheave axle.

2. When using the the 1/2" x 27" belt you have a trade-off going on, in that the longer 27" belt keeps the belt from going into the fingers of the idler sheave at the "FAST" setting that the narrower 1/2" belt would tend to do - but the the added length compensates for the narrower belt - even allowing for the factory speed ranges.

I suspect that the 1/2" x 27" belt tends to skew the RPM range to what is indicated on the speed dial in some minor direction - either up or down - as it seems no one would ever buy the single source and $$$ SS belts if the 1/2" x 27" was a perfect replacement.

Comments please?

You cannot ignore the difference in thickness(5/16 vs 3/8).

BTW I assume the side angle is the same for both.

The range and hi/lo speeds are dependent upon how the belt rides in the pulleys as well as the width and length. The wider belt will cause the sheaves to be open wider at a given rpm.

This may help the belt jammed into the idler pulley sheaves, but may restrict the hi speed attainable.

Also the belt must ride higher in the motor pulley for the same reason.

The length affects the speed limits (longer limits high speed attainable, shorter limits low speed attainable.(both assuming 'normal speed at the opposite extreme).

I have fooled around with these enough to come to realize that the 1/2"+(less than 9/16") x 26.5 belt is necessary with the hardware it mates with. I have tried 1/2" x 26" belts with the motor spaced towards the idlershaft 1/4" and the correct speed range is obtained. The motor mounting holes in the motor pan need to be elongated to do that.

A word of caution, the belt purveyers have gone to thinking metric and not all 1/2" belts are 1/2". 12mm does not equal 1/2 inch. It really needs to be oversize, not smaller.

Shopsmith 'tried' standard belts a while back(Gates IIRC) and that was not a good thing!!!:eek:

FWIW the movable(both control and floating) sheaves have hard limits to their range of motion. Those limits come to bear at the low end(that is what stops the dial from moving further). You cannot push the control sheave too far, and the floating sheave can only move in so far.