I need some help trying to figure out why my Grizzly 1067z lathe suddenly doesn’t get up to top speed, in other words as I turn the speed selector from slow to fast, it only seems to get about half the speed it used to, and at the slow speed setting it hardly turns at all. The motor seems to work fine, I checked the contacts on the clutch and they were good, I suspect may be the belt tension but have to admit I do not understand how the split pulley for speed selection works, it opens and closes as you move the speed selector, and the belt seems tight when the two halves of the pulleys are at their closest, but flops around when they are moved apart from one another. Do i need a new belt? I just don’t know enough of how this type of pulley works to know what is correct and what is not. The machine is almost two years old but I doubt it has 60 hours of use to date, it was a gift from my wife and at least until recently of little interest to me.
Thanks for any advice
uncletim
Replies
It's called a Reeves Drive. When one pulley is fully closed the other is fully open. Sounds as if you you need to adjust the spacing of the motor which is critical of that type of drive. With 60 hours it's unlikely you need a new belt. Have you checked your manual for setting belt tension or called Grizzly tech help? The manual should your first place to got then the tech should be your next place to check with.
The halves of both pulleys move closer together or further apart as you change the speed, as one moves together the other one moves apart so that the tension stays the same but the relative diameters change. The mechanism only works when the pulleys are spinning, trying to move the speed control with the motor off will only jam things up and possibly damage something.
The spacing on one pulley is controlled by the linkage of the speed control mechanism, but the spacing on the other pulley is controlled by a spring that forces the two pulley halves together to take up the slack in the belt. If something like dust or lack of lubrication hangs up the sliding motion of the two halves of the spring loaded pulley you will get the symptoms you describe. The solution is to gain some access to the spring tensioned pulley and at least clean and lube it in place. If the pulley is really bound up it will have to be removed and disassembled for a thorough cleaning, a moderately time consuming job.
It is possible on some machines, depending on the drive design that the linkage controlled pulley could be hanging up instead, but the solution is basically the same, it will need to be cleaned and lubed.
John White, Shop Manager, Fine Woodworking Magazine
JohnI really appreciate your thoughtful, lucid comments. Jerry
Thank you for your help. You were right that it needed a good cleaning as one half of one pulley was not moving, looks like factory grease that had hardened, I cleaned it, applied a dry lube and was back in business. thanks again.
would have replied sooner but was out of town.
tim
You're welcome, I was glad I could help.
John W.
Edited 6/29/2006 2:17 pm ET by JohnWW
I will throw my .02 in here as I owned a Grizzly for some time and was rather happy with it. I also experienced similar type problems on my speed and found that the grease that was applied to the internal spindle had solidified. The reeve’s pulleys were basically sticking on the spindle. I ended up giving the spindle several bathes in WD-40 until I removed all that mess and then lubricated with a dry lubricant. It worked great for me so that’s what I would check.
Ken
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