Jointer belt pulley keeps coming loose

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Forum topic by gsimon posted 02-15-2016 11:40 PM 1316 views 0 times favorited 10 replies Add to Favorites Watch
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1300 posts in 2352 days

02-15-2016 11:40 PM

Topic tags/keywords: jointer repair

Hi All
The allan screw on in my pulley vibrates loose and therefore the shaft spins on it’s own or friction
I keep lining it up, tightening it but it keeps vibrating loose

Maybe it’s set up wrong?
I can’t see using Locktite on it as I want to be able to service it
Why is there another allan screw off to one side (only one groove in the shaft)
The first pic shows it loose and out of line and the second pic shows it lined up and tightened

any thoughts?

-- Greg Simon

10 replies so far

View MrUnix's profile


7107 posts in 2438 days

#1 posted 02-15-2016 11:43 PM

It has a keyway, so it appears you are missing the key – as otherwise, it would not be able to rotate like that. And in the second picture, it’s not lined up properly – the keyway in the pulley needs to match up with the shaft:


-- Brad in FL - In Dog I trust... everything else is questionable

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13641 posts in 3580 days

#2 posted 02-15-2016 11:53 PM

keys and allen screws can be had at any good hrdw store

in the metal drawers section

allen screws can get a round bottom
from slipping on round shafts
and can’t be tightened anymore
the new ones have a semi point
that allows them to turn completely

take the screw with to get the right threads
and measure the key for size
(they come square)

-- david - only thru kindness can this world be whole . If we don't succeed we run the risk of failure. Dan Quayle

View joey502's profile


544 posts in 1757 days

#3 posted 02-15-2016 11:54 PM

Like Brad said the key is missing and it is a needed part for sure. You should be able to get a new one locally with out much effort. The key for that should be a standard size, it was not custom made for that model machine.

Did you buy the jointer new or used? It seems you would have lost some power at the cutter head without the key in there. The pulley would have been spinning faster than the shaft when under a load.

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1300 posts in 2352 days

#4 posted 02-16-2016 12:07 AM

I pulled this from the back room at work and it needed some TLC so i put a new belt, bearings and sharpened the blades and have been using it for a few years now
I though the Allan screw just ran into the slot as that’s what was always there
I didn’t it was supposed to have a key?

When the screw works loose then it does lose power up to the point where it just doesn’t move when pressure is applied

I’ll look for a key and then line it up properly
That would still leave me with one allan screw not doing anything wouldn’t it?

thanks for all your help guys –
i hate having these rookie questions to ask but I really appreciate the feedback for sure

-- Greg Simon

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955 posts in 1391 days

#5 posted 02-16-2016 12:16 AM

Agree with all said here, and Blue LocTite holds but does not need a release solution like Red. Use the right set screw also, see pic.

-- Knowledge and experience equals Wisdom, Michael Frankowski

View martyoc's profile


44 posts in 1156 days

#6 posted 02-16-2016 12:30 AM

You need both the key and the setscrew. The key, as has been pointed out, prevents the pulley from rotating on the shaft. The set screw prevents the pulley from slipping along the shaft.

-- Marty O'C

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19622 posts in 2096 days

#7 posted 02-16-2016 12:34 AM

One set screw has a key way under it and the other does not. You will need to use the set screw that has the key way under it. I believe the other set screw is for use on a shaft that has a flat spot. I imagine you can take that screw out.

-- Bill M. "People change, walnut doesn't" by Gene.

View devann's profile


2246 posts in 2932 days

#8 posted 02-16-2016 01:22 AM

Greg, after reinstalling the key and before replacing the set screw you can use a small amount of boiled linseed oil instead of Locktite as thread locker.

-- Darrell, making more sawdust than I know what to do with

View gsimon's profile


1300 posts in 2352 days

#9 posted 02-16-2016 02:25 AM

thanks again guys – this will obviously make it much safer too

-- Greg Simon

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22012 posts in 2922 days

#10 posted 02-16-2016 02:29 AM

One other item…IF there is enough room, use a second set screw on top of the first, it will lock both in place, yet be easy enough to remove.

-- A Planer? I'M the planer, this is what I use

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