Drill Press spindle bearing replacement

I have a nice 20" Dayton Drill Press. It practically has no runout but bearing make some ugly noise. What is involved in spindle bearing replacement procedure? Do I need any special tool? Can I introduce spindle runout while replacing bearings?

Thanks, Alex

Reply to
AK
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Should be pretty straightforward. What's the number etched into the outer race of the rumbly bearing?

Reply to
Dave Hinz

I don't know yet. I haven't disassembled it yet. BTW It's just my guess that it's a bearing. Didn't want to start if too much is involved.

Reply to
AK

It's NTN 6204z on upper and NTN 6206z on lower. I can't say which one is rattling. I'll replace both. What kind of puller do I need to remove the bearings? Do bearing dealers provide any tool rental or I'll have to buy a puller etc.?

Thanks, Alex

Reply to
AK

Before you dig too deep, look up a document someone here on RCM wrote called, IIRC, "How to buy a drill press" and use the checklist he has to see what's actually wrong. As I remember, bearings are not the only parts of these that make noise, it can also be worn splines.

Hope that helps, --Glenn Lyford

Reply to
glyford

Grant Irwin did a nice piece on drill presses. Check

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Bob Swinney

Before you dig too deep, look up a document someone here on RCM wrote called, IIRC, "How to buy a drill press" and use the checklist he has to see what's actually wrong. As I remember, bearings are not the only parts of these that make noise, it can also be worn splines.

Hope that helps, --Glenn Lyford

Reply to
Robert Swinney

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armed with a pot of common old grease. flip the lid orff the top of the pulley safety case. pull the quill down. squidge in a few gollops of grease into the hole on top of the quill. when you cant get any more grease in, place your thumb over the hole to seal it off. let the quill rise to the top of its travel. this will squish grease down around the quill. lift your thumb off and then pull the quill down again. squidge in as much more grease as you can. place thumb over the top of the quill again and release the quill. repeat until you cant get any more grease in.

the grease now all the way along the quill will kill most of the rattle.

Stealth Pilot

Reply to
Stealth Pilot

Check

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But if rattle is inside the bearing no grease can't help it. May be just dampen the noise?

Reply to
AK

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Damned if *that* wasn't a timely response! Thanks.

I too just picked up a bench model drill press which sounds almost exactly like Grant's description. It's an Associated Machine Tool (Taiwan) 1/2 hp, 5 speed made in 1978. A friend of mine has a 15 speed AMT with th' idler pulley like Grant's, mine doesn't have one.

It seems to me that mine needs a spring loaded belt tensioner since there's a *lot* of slop in th' belt at every speed except th' lowest,

460 rpm. Any of youse ever make a mod like this before?

There's also a lever that, for th' life of me, I can't figure out what it's s'posed to do... don't laugh. Well, Ok, go ahead, but WTF does th' lever on th' right upper side (facing it) back close to th' motor in th' head casting do? It rotates about 120 degrees and seems to engage something in th' 3 O clock position, but it doesn't *do* anything. That lever goes all the way horizontally through th' head casting.

My friend's has th' same lever, but it's stuck in th' 8 O clock position.

Also, my buddies table crank is obviously stripped out. We assume it's got a set of worm drive gears that raise/lower it on th' column teeth. Best guess is someone ham fisted it while it was locked. Are there parts available for these critters? My cursory search for Associated Machine Tools was fruitless.

Thanks again for th' link and to Grant for writing that up!

Snarl

Reply to
snarl

See if it looks like these:

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If so I have the few sheets of paper some might call a manual that came with'em.

I happened to have the images around, sorry that they sorta suck...

Reply to
Leon Fisk

Very similar, but there are a few minor differences. Ours both have a separate Light and Motor switches and they have a head stock lock lever on each side of th' column. Obviously th' same manufacturer tho. Mine's a Model # AG 5-IND, serial number 11406. Dunno what my bud's is.

I'd really appreciate a copy of those. This addy is munged, but ping me at snarl 67 at trip dot net (remove th' spaces and change th' obvious) and I'll send ya a snail mail addy. Be sure to include yer return address so's I can send ya a few bucks for a libation of choice for your effort .

Thanks!

Snarl

Reply to
snarl

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Not needed. See later.

That lever is *supposed* to move the motor mount platform forward and back -- after you loosen the clamp bolts (usually a single pivoted wing on each) which hold the motor in position. then, you use the lever to pull the motor as close to the column as possible, slip the belt in position, and then use the lever to move the motor back until the belt is tight enough, and holding it in that position, tighten the clamp bolts.

It sounds as though someone managed to strip the teeth off the pinion -- or the whole thing slid out of position and is no longer engaging the rack gears on the motor plate mount bars.

Or -- some of them simply have an arm coming out the center of the bolt which is pivot connected to another arm which has its other end connected to the motor mount plate. The behavior of yours sounds like that kind, with the pivot pins disconnected somewhere. If necessary, unscrew and remove the belt guard on the top of your machine's head, and use a flashlight to see what the lever actually is trying to do, and reconnect the linkage and replace the missing pin, screw, or rivet.

Loosen the clamp bolts for the motor mount plate, and I'll bet that his moves -- and moves the motor to provide more or less slack on the belts.

Keep your eyes open for a base, column and table without a head on eBay. Sometimes these show up. Or strip it apart and make a new worm and gear.

Good Luck, DoN.

Reply to
DoN. Nichols
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Are you sure that those are not for locking the motor position? That's what mine (not an AMT) has -- and that allows the mystery lever (from your other article) to move the motor back and forth to tighten the belt. But you'll first have to fix the link from the mystery lever to the motor mounting plate.

Good Luck, DoN.

Reply to
DoN. Nichols

yup if it is a bearing a new one is in order. all drills I've encountered new rattled quite a bit. they quieten down considerably with a quill full of grease.

havent you fixed it yet?

Reply to
Stealth Pilot

I took the spindle to BB dealer who took it apart and found a problem. It was a thrust bearing inside the spindle. I replaced all three bearings anyway.

Reply to
AK

It will take me a bit, but I'll get something for you. I'll hang on to this message and get back to you. Can you print stuff? Being you mentioned snail mail thought I would ask.

I thing Don's reply probably answers your lever question. My two only have the thumb-bolts on either side for locking the motor mount sliding posts. Try loosening both motor mounting thumb-bolts and moving your lever again. I took a look yesterday and didn't see any other levers on them in the area you mentioned.

These both came without motors. My Dad bought'em that way and cobbled his own motor on. I not sure where they came from, but he bought stuff from Harbor Freight and US General among other odd places. These are probably early 1980's vintage.

Reply to
Leon Fisk

No, I'm not sure. Upon further examination, it appears that to lock th' head from swiveling you need to tighten two blind allen screws on th' right side of th' head. I think you're right about them having to do with belt tension.

Which means acquiring another 1 1/16" deep socket to remove th' spindle pulley so I can remove th' belt guard assy. Crap, who'd I lend that too...

Thanks DoN, this project is gonna have to go into a holding pattern for a bit now. I am curious as hell what I'll see in there tho. If it turns out that I'll need to buy or make parts, I may still modify a spring loaded tensioner out of a spare one off a motorcycle I have as a temp fix. You know, one of those fixes you'll do right some day later .

Snarl

Reply to
snarl

Yes, I have a printer and I'm in no rush, Leon. Thanks!

I tried that and nothing happened. Gotta get inside and take a look. This drill press was in th' Lake Union Drydock machine shop before my bud got it. I suspect they busted th' linkage, or whatever mechanism moves th' motor, and purchased a new replacement. Lotsa waste in that shop... union shop I might add .

Thanks again.

Snarl

Reply to
snarl

That is what mine has -- wit the sub-surface Allen head setscrews for locking to the column.

Not necessarily. At least based on mine, you can remove the screws which hold it in place, and the belt(s), and just swing the belt guard to one side or the other. (I had to do this to enlarge a hole in the bottom of the belt guard which cleared the pivot for the intermediate pulley (mine is a 16-speed), and this should at least let you look down into the head casting to see how that outside lever links (or at least *should* link) to the motor casting. After sending last night, I went down to the shop and looked, and I don't see any clues of the linkage between the motor and the casting, so I guess that it ties to the inboard ends of the motor guide rods.

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I understand that all too well. :-)

Good Luck, DoN.

Reply to
DoN. Nichols

you know you'll have to make something now :-) put it to use and enjoy it.

Reply to
Stealth Pilot

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