Delta/Rockwell 6" jointer

[milomilo]

Figure I might as well start a dedicated thread on my jointer. It has a ID plate titled Rockwell with BP4870. Not sure if it is a model on the S/N. Anywho, The RPMS are not right. Too slow. Went though the Pulley Calculator and through my boxes of pulleys and was able to to get a combination that gave me 4640 RPMS. Ended up with a 12" on the motor and a 4 1/2" on the jointer. Motor s a 1740 RPM.

I went through all my V belts and had to break down and buy a belt. The 12" pulley I have does not have a set screw, so had to drill and tap for a 1/4-20. Was quite a challenge, as the hub is very close to the outer rim and also had to rig up and extension for drilling the hole. Turned out well. Now have to install the 4 1/2" pulley and tighten up the motor base bolts and give it a test run.

Also have not found anywhere to lube the arbor spindle. It turns easily with one finger with no side play. Have not found a manual for it yet either. Hoping the pulley calculator is right on the belt size, if not back to the hardware store for an exchange.

[milomilo]

More pics.

[LKeithR]

Originally Posted by milomilo

...Ended up with a 12" on the motor and a 4 1/2" on the jointer. Motor s a 1740 RPM...

Be careful when running that 12" pulley at that speed. At 1740 RPM it works out to almost 5500 SFM which is very fast for a pulley of that size--large spoked pulleys have a habit of coming apart if they are run too fast. The centrifugal load on the rim will be very high. A nick or minute crack will create a weak spot that could cause the rim to explode. If that were to happen at speed the broken pieces could be deadly...

[milomilo]

Originally Posted by LKeithR

Be careful when running that 12" pulley at that speed. At 1740 RPM it works out to almost 5500 SFM which is very fast for a pulley of that size--large spoked pulleys have a habit of coming apart if they are run too fast. The centrifugal load on the rim will be very high. A nick or minute crack will create a weak spot that could cause the rim to explode. If that were to happen at speed the broken pieces could be deadly...

Did a test run and the cast iron pulley is causing vibration. Runs very true when spun by hand, but the OD has some variation. It is on the motor so only running 1740. Gonna get a small grinder and see if I can true it up by running it up to speed and then turning it off and running the grinder as it slows down.
I did spin it by hand with the belt off and it stops at a different place each time so cannot down a heavy end.

[digr]

This should be your manual, if not look around and you should be able to find it.

[digr]

Here is a rpm calculator
I am guessing but it looks like they have a six inch turning a two inch which in your case would give you 5220

[milomilo]

Originally Posted by digr

This should be your manual, if not look around and you should be able to find it.

The stand is different but the jointer is right. Thanks. I did see that the blade arbor has sealed bearings, so no maintenance. Pulleys on belt off. Snowing now so back at it later.

[Lew Hartswick]

Why in the world is the pulley on the cutter head so large. My 6" jointer has a 2" one and it never has any problem slipping . Been there for over 40 years and done a lot of cutting.
...lew...
Look at the pulley, B , on Pg4 of the manual above . That is about 2" just like mine . That should make the motor one a LOT easier to handle. :-)
..lew..

[milomilo]

Originally Posted by Lew Hartswick

Why in the world is the pulley on the cutter head so large. My 6" jointer has a 2" one and it never has any problem slipping . Been there for over 40 years and done a lot of cutting.
...lew...
Look at the pulley, B , on Pg4 of the manual above . That is about 2" just like mine . That should make the motor one a LOT easier to handle. :-)
..lew..

Going through my pulleys left me with this set to get the right RPM. Kinda like make do with what you got. If I do not get the vibration out I may have to redo the pulleys.

[USMCPOP]

I have a Rockwell like that. Big pulley is appx 7" OD, small one about 3" OD. Can't see the motor RPM offhand as it's stuffed in a corner behind a 2,400 lb vertical mill.

I got it off Craigslist for free, never ran it.