Vibration problems with Rigid 1/2HP 1Ph drill press

[mindedc]

I was hoping to get some advise/information. I recently bought a Rigid 15" drill press with a 1/2 hp 1Phase motor. This was a craigslist buy with several other tools in "the deal" and the drill press was the "nicest" item and looked to be in the best shape. I checked the obvious visual stuff (grabbed the chuck and shook it to see if the support bearings are shot in the quill, ran the quill up and down etc....) and it looked fine. I powered some of the other items on and they were fine. I didn't power the drill on. Shame on me.

When I got home I cleaned it up. The original owner didn't do a good job of removing all the cosmoline packing. There was still oil soaked paper between some of the parts. The chuck was so full of dryed out cosmoline it would barely open. I used 1/4 can of carb cleaner and a dozen shots of penetrating oil (pblaster brand) and solved that problem nicely.

When I powered it up, the machine made a 1-2 second shriek when initially starting , think squealing belt on a car. After it's up to speed, the press vibrates and the quill mechanism rattles from vibration, the belt housing buzzes like crazy. It's extremely loud.

I've used a few drill presses over the years, I've never seen one act like that. I am severely disappointed with only myself to blame. Terrified the press was garbage, I chucked up a new 3/8 bit and made a hole in some scrap MDF. The hole seemed extremely precise, zero play in it when sliding it back on the bit by hand.

This makes me think that the chuck/quill mechanism is fine, but the vibrations/noise are from the motor/drive train and will become a problem if left untreated (ruined bearings).

I only had a little time to fool with it because we were going out of town for the holidays. The wisdom of the internet is that belts can get formed around the pulleys and cause vibration. I'm not sure that is my problem here as these belts are multi-groove miniature serpentine type belts, not a regular "fan belt" style. They seem very flexible. They do hold a certain amount of their shape off the machine. The belt housing was showing a lot of debris that in retrospect is probably off the belts so I went ahead and ordered a new set of belts. After reading the owners manual there is an apparent setup step of leveling the tops of all the pulleys to get it in line. I figure that the original assembler didn't even get all the packing materials off, the probability of them aligning the pulleys is pretty small. I'll have to wait to get back home to validate that.

Unhooking the belt from the motor cured the shriek, didn't really change the vibration. I put my hand on the motor and it's vibrating like crazy. My 1/4HP Delta runs quietly with a minimal amount of vibration. The delta motor lightly vibrates if you put your hand right on it and that does not change if I un-hook it's belts. I did some reading and I'm hoping it's the fan or the pully that is out of balance on the Rigid.


If not, my first question is, If the motor itself is out of balance, should I:

a. Try and balance it myself (static balance on knife edges - redneck method)
b. Have it balanced by a motor shop($$?)
c. Just replace the motor with a quality TEFC unit.

I'm guessing for a $150-$200 motor that having it balanced is going to be as much as a new one costs. This motor looks identical to the 1/2 horse unit that Grizzly sells (H5374). That makes me think it came out of the same factory in china.

If I do try and balance it myself, how smooth should a 1Phase AC motor run? Could I even fix the problem? I don't have anything else with a similar induction motor, but I remember being around a lot of machines with similar motors that ran very smoothly... could be my memory though.... I've rebuilt many small electric motors (used to race RC cars) so I'm not afraid of disassembly/reassembly of the motor itself. I simply fear that balancing a motor without a machine is a waste of time.

If I do replace the motor, there are several brands like leeson, AO smith, GE, etc... Any of these better or worse for such an application? I know Baldor motors are fabulous but the cost is high. Looks like there is an appropriate leeson on amazon that is less than the above Grizzly. I think leeson has a better reputation than Grizzly..

Any input/advise you guys have would be greatly appreciated. If anyone else has dealt with similar issues that would especially be appreciated.

Thanks!

 

[454ragtop]

First thing to do is check to make sure it is wired correctly for the voltage. Then I'd remove the pulley from the motor, to narrow it down to either an out of balance pulley or a motor problem. If a motor problem, probably take it apart and see if there is anything obvious wrong with it. If you need to replace the motor, a TEFC isn't required, don't ever remember seeing one as OEM. I'd just look for an American made 1/2 HP motor on CL, shouldn't be too hard to come by, long as it's a std frame.
Good luck, Jim.

 

[PT Doc]

Tighten the ribbed belts quite tightly. That should help a lot. Use a dial indicator if you think the motor shaft or the pulley is the culprit. Make sure the belt housing is tight on the head unit. I think you will find that this drill press is quite capable of getting set up to have about 1.5-2 thou runout. Use screw machine bits and you will drill nice holes that are square to the material if you make sure that your table is square to the spindle. I put a jacobs 16n Chuck on the jt3 taper and I feel that it was a great improvement. Hope this helps.

 

[mindedc]

First thing to do is check to make sure it is wired correctly for the voltage. Then I'd remove the pulley from the motor, to narrow it down to either an out of balance pulley or a motor problem. If a motor problem, probably take it apart and see if there is anything obvious wrong with it. If you need to replace the motor, a TEFC isn't required, don't ever remember seeing one as OEM. I'd just look for an American made 1/2 HP motor on CL, shouldn't be too hard to come by, long as it's a std frame.
Good luck, Jim.

There is only "one" wiring for this motor, but it looks like there are multiple coils to be connected. I'll open it up and check it against the diagram on the side of the motor. The TEFC was added apparently in a revision to the product because they had a few machines get enough saw dust in them to have a problem. Frankly I don't know WTF you'd be doing with a drill press to make enough sawdust to contaminate the motor.... I figured if I get to the point of ordering a replacement motor I'll disassemble the one on it first as a last ditch effort.

Tighten the ribbed belts quite tightly. That should help a lot. Use a dial indicator if you think the motor shaft or the pulley is the culprit. Make sure the belt housing is tight on the head unit. I think you will find that this drill press is quite capable of getting set up to have about 1.5-2 thou runout. Use screw machine bits and you will drill nice holes that are square to the material if you make sure that your table is square to the spindle. I put a jacobs 16n Chuck on the jt3 taper and I feel that it was a great improvement. Hope this helps.

This info is a huge help. That's good info on the belts. The manual says to tighten where it's 1/2" of deflection but it didn't say how much force to use deflecting... I did check the squareness of the table with my machinists square and it's out 1/2 a degree or so. I will adjust it when I do a full setup. The table adjusting nut feels like it will need an impact or at least a breaker bar to remove, I wanted to verify the thread direction before putting my 1000ftlb IR impact on it I ordered a dial gauge and magnet block to check runout, should be home the day after I get back. Something I was wanting to add to my collection anyway.... Good info on the chuck and the belt housing... I had looked at these in the store and thought that they looked like nice machines, you've confirmed my belief. I'm sure I've got a solvable problem here...

Thanks for the assistance!

 

[PugetDude]

Try a link belt instead of the original belts.

 

[Outlander]

Interesting. When I was watching the videos they mentioned the standard rubber belts taking the form of the pulley when sitting over time. My drill press, table saw and band saw all sit for extended periods of time (in an unheated garage in the winter). I do occasionally use the drill press, very very rarely the saws. I have never paid much attention to the belts, or their shape.

Thanks for contributing to my education

 

[mindedc]

Try a link belt instead of the original belts.

I would certainly do that if I could. My dad has link belts on his contractor saw and band saw and they make a nice improvement.

These things are a little different and use "poly v belts" like such:

http://www.shailinternational.com/im_src/poly_v_belts_im.jpg

They look like little miniature serpentine belts... These feel a little more flexible like they wouldn't get kinked. I would have done more investigating before ordering new if there weren't tiny chunks of rubber in the top...

 

[t4runner]

As others have said the belt ( even a new one ) can cause more vibration then you know, if everything else looks good get a linked belt. I would get one in any event.

 

[mrvm]

Check out the Ridgid tool forum for tips on getting that drill press running right. They have a section on power tools / wood working

www.ridgidforum.com/

 

[kossuth]

I don't know much about that machine or the belt situation, but I would give the motor mounts a check and make sure they are good and tight.

 

[Davefr]

You need to pinpoint the root cause of the problem!

I'd totally remove the motor from the DP and then remove the pulley from the motor. Now test it on the bench. If it still vibrates then it could be a bent rotor shaft, bad bearings or a rotor that isn't concentric with the stator. (Loose or misaligned end caps can cause rotor/stator concentric alignment problems.)

Bearings are cheap, alignment is easy to do but a bent shaft will be a showstopper.

1/2HP 1750 motors aren't hard to find on Ebay, CL or even HF.

 

[exmaxima1]

Motor with no belt should not vibrate. Buy a 1/2hp motor from CL or fleabag for $40 and save time.

BTW, those Ridgid drill presses with Multi-v belts should run extremely smooth. I retrofitted Multi-v pulleys and belt from a Ridgid table saw to a POS Craftsman saw and it cured all the vibration---and takes a long time to spool down due to the low friction of those belts. Multi-v can deliver much more power than those link belts as well.

 

[Cope]

Interesting. When I was watching the videos they mentioned the standard rubber belts taking the form of the pulley when sitting over time. My drill press, table saw and band saw all sit for extended periods of time (in an unheated garage in the winter). I do occasionally use the drill press, very very rarely the saws. I have never paid much attention to the belts, or their shape.

Thanks for contributing to my education

The cheap Chinese belts take a set, but good quality US belts should be OK.

 

[mindedc]

This is why Garage Journal is awesome, good info from a dozen directions in less than 24 hours.

A lot of this confirms my suspicions. The motor mount is quite solid and the motor vibrates like crazy. The above information on the smoothness of the poly-v-belt setup double confirms that the motor/fan/pulley setup is likely 90% of the problem and perhaps a mis-aligned pulley is the other 10%. I will be certainly taking the motor off the drill and dis-assembling it until I find the source of the problem.

I'm pretty convinced a new motor, pulley alignment, and new belts will put this thing right again. I'm going to try and "repair" the motor as it would be a shame if I bought a new one and an out of balance fan is causing all the problems... Worst case I will buy a motor from somewhere.

Will be back in town monday or tuesday to try it out and will post the results and a few pics if I can.