OT Spindle Taper Machining?

[mcpgmr]

We had a machine crash the other day. The operator has to hand load one of the tools and he loaded it wrong with the flange on top of the keys. 8" face mill. I can't believe the machine went into cycle but it did. Well when it engaged the material the tool came out and in the process it damaged the Cat 50 taper in the spindle. Our machine repair guy came in this morning and tried to stone it and was able to get a tool holder back in and running within .002" but recommended that we call a guy who specializes in this type of repair. The guy has a special grinding jig that mounts to the spindle housing and can accurately regrind the taper. Well the boss said no and is going to try and fix it by mounting a turning tool to the table and take the high spots off manually. I think he's an idiot for even trying and is going to ruin the spindle for good. Any suggestions or ideas before he does? I might be able to stop him.

[Rick Henrickson 65]

you will ruin the spindle if you do that. It has to be reground and blued to check for contact, is this CAT, BT, etc.

you would be better off hand working it with a stone and craytex.

 

A spindle grind is much cheaper than a new spindle.

[mcpgmr]

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A spindle grind is much cheaper than a new spindle.

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Thanks! As I said the repair guy recommended that and our resident genius won't listen. So when the spindle is ruined he deserves an "I told you so". Stupid is as stupid does!

[Kevangel]

After stoning real bad spots, have you tried putting lapping coumpound on an old tool holder?

coarse then fine, etc.

I recently got an advertisement in the mail from a company (CAT spindle grind service)www.catspindlegrinding.com letter sez $450 for 50 taper plus .75cents per mile and discount for multipal tapers.

[Chris Rizzo]

not really in your area, but www.cncmachinesales.com

has the gear and know-how.

 

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Well the boss said no and is going to try and fix it by mounting a turning tool to the table and take the high spots off manually

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that sounds like a canidate for the machine-shop darwin awards.

[G Caputo]

We had one done for under $1000 one time and not long thereafter it got crashed again. Mount a die grinder with a stone in it to the table, turn on the spindle and feed the machine at the correct angle and do it yourself. Not really all that complicated. Jm2c.

[crazy^millman]

I have seen about 5 machine have the spindle reground and the best way any other way is a disaster waiting to happen. A proper person will readjust your fingers and reshim the gripper fingers to grab the pull stud. .0001 is to much anything greater than that and you are going to have problems. That 8" facemill with .002 runout at the taper is about .018 at the inserts going to be hard to machine anything flat or accurate. Tell the resident idiot to STFU and let a pro come in and do it right.

[jeff]

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Tell the resident idiot to STFU and let a pro come in and do it right.

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YEAH!!

[mcpgmr]

He's out there now giving it a hand job with a stone and some emery cloth. Guess he changed his mind about the tool bit and trying to cut it.

[doyleg]

I've had ours done here and at other places. They do a complete check on taper, pull strength and everything. Worth every penny.

 

If he crashed it that hard I wouldn't be surprised if some of the washers in the pull bar are not busted and your not getting an even clamp on pull stud.

 

By the way. If all things are considered. To have it done for under $1000 is worth every penny. I think the avg price here was around $600 per. If you had any chatter from that machine in the past, this may well take care of some, if not all, of the chatter.