taking rotor apart

Post Reply
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

taking rotor apart

Post by 8parktoollover »

I attempted taking my bach rotor apart. I took the linkage and valve cap off and got to the step of tapping it with the hammer and the valve just wouldn't come out. I gave up in fear of damaging it but it is quite dirty and I would like to be able to clean it myself.
User avatar
Burgerbob
Posts: 4647
Joined: Mon Apr 23, 2018 8:10 pm
Location: LA
Contact:

Re: taking rotor apart

Post by Burgerbob »

Keep tapping. Lots of light taps.
Aidan Ritchie, LA area player and teacher
Bonearzt
Posts: 721
Joined: Thu Mar 22, 2018 7:40 am
Location: My Dungeon of Hell....Actually Texas
Contact:

Re: taking rotor apart

Post by Bonearzt »

You need to pry off the stop arm from the rotor spindle, sometimes a large flat screwdriver works or a paint can opener. Wedge the tool under the stop arm and on top of the bumper plate and carefully leverage the stop arm up.

DO NOT wedge the screwdriver anywhere against the valve casing!!!!!!!

You can also insert a semi-round tool in the end of the stop arm against the spindle and carefully tap the valve out that way.

If none of these make sense, take it to a tech and ask them how to remove the rotor!

Eric
Eric Edwards
Professional Instrument Repair
972.795.5784

"If you must choose between two evils, choose the one you haven't tried yet."
"Rather fail with honor than succeed by fraud." -Sophocles
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

Bonearzt wrote: Mon May 04, 2020 12:41 pm You need to pry off the stop arm from the rotor spindle, sometimes a large flat screwdriver works or a paint can opener. Wedge the tool under the stop arm and on top of the bumper plate and carefully leverage the stop arm up.

DO NOT wedge the screwdriver anywhere against the valve casing!!!!!!!

You can also insert a semi-round tool in the end of the stop arm against the spindle and carefully tap the valve out that way.

If none of these make sense, take it to a tech and ask them how to remove the rotor!

Eric
I did that
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

Burgerbob wrote: Mon May 04, 2020 12:39 pm Keep tapping. Lots of light taps.
I think it's safe to say that I tapped it many many times
Bonearzt
Posts: 721
Joined: Thu Mar 22, 2018 7:40 am
Location: My Dungeon of Hell....Actually Texas
Contact:

Re: taking rotor apart

Post by Bonearzt »

8parktoollover wrote: Mon May 04, 2020 12:45 pm
Burgerbob wrote: Mon May 04, 2020 12:39 pm Keep tapping. Lots of light taps.
I think it's safe to say that I tapped it many many times
Either not tapping in the right place, or not tapping firm enough!
Eric Edwards
Professional Instrument Repair
972.795.5784

"If you must choose between two evils, choose the one you haven't tried yet."
"Rather fail with honor than succeed by fraud." -Sophocles
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

Bonearzt wrote: Mon May 04, 2020 12:46 pm
8parktoollover wrote: Mon May 04, 2020 12:45 pm
I think it's safe to say that I tapped it many many times
Either not tapping in the right place, or not tapping firm enough!
I tapped it on the spindle and I think I tried doing it pretty firmly
timothy42b
Posts: 1479
Joined: Tue Mar 27, 2018 5:51 am
Location: central Virginia

Re: taking rotor apart

Post by timothy42b »

I just got mine out and looked. It's been in the case awhile, doesn't get played much. 42B I bought new in 1971.

The valve had not been removed in at least 25 years the first time I took it out. It took a good bit of tapping but it came. I can't imagine yours is stuck worse, unless? bumped or dented or something?

At any rate, you have the linkage all the way off so the spindle can go down inside without obstruction, right? The advice used to be put the screw back in the spindle and tap on that, I don't know if that's still recommended but it worked for me. I've watched others do it and it seemed to come out easier than on mine. Unless there's something wrong it should come out, I would think, if you tap long enough.
Bonearzt
Posts: 721
Joined: Thu Mar 22, 2018 7:40 am
Location: My Dungeon of Hell....Actually Texas
Contact:

Re: taking rotor apart

Post by Bonearzt »

timothy42b wrote: Mon May 04, 2020 1:42 pm I just got mine out and looked. It's been in the case awhile, doesn't get played much. 42B I bought new in 1971.

The valve had not been removed in at least 25 years the first time I took it out. It took a good bit of tapping but it came. I can't imagine yours is stuck worse, unless? bumped or dented or something?

At any rate, you have the linkage all the way off so the spindle can go down inside without obstruction, right? The advice used to be put the screw back in the spindle and tap on that, I don't know if that's still recommended but it worked for me. I've watched others do it and it seemed to come out easier than on mine. Unless there's something wrong it should come out, I would think, if you tap long enough.
I never recommend tapping on the screw!!! Too easy to hit off-center & bend it!

Sometimes it takes quite a bit more force than you think to pop out a rotor!!


Eric
Eric Edwards
Professional Instrument Repair
972.795.5784

"If you must choose between two evils, choose the one you haven't tried yet."
"Rather fail with honor than succeed by fraud." -Sophocles
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

Bonearzt wrote: Mon May 04, 2020 1:51 pm
timothy42b wrote: Mon May 04, 2020 1:42 pm I just got mine out and looked. It's been in the case awhile, doesn't get played much. 42B I bought new in 1971.

The valve had not been removed in at least 25 years the first time I took it out. It took a good bit of tapping but it came. I can't imagine yours is stuck worse, unless? bumped or dented or something?

At any rate, you have the linkage all the way off so the spindle can go down inside without obstruction, right? The advice used to be put the screw back in the spindle and tap on that, I don't know if that's still recommended but it worked for me. I've watched others do it and it seemed to come out easier than on mine. Unless there's something wrong it should come out, I would think, if you tap long enough.
I never recommend tapping on the screw!!! Too easy to hit off-center & bend it!

Sometimes it takes quite a bit more force than you think to pop out a rotor!!


Eric
I was hitting it pretty hard but I don't want to force it and damage something
bigbandbone
Posts: 588
Joined: Thu Jan 17, 2019 7:45 am

Re: taking rotor apart

Post by bigbandbone »

Bonearzt wrote: Mon May 04, 2020 12:41 pm You need to pry off the stop arm from the rotor spindle, sometimes a large flat screwdriver works or a paint can opener. Wedge the tool under the stop arm and on top of the bumper plate and carefully leverage the stop arm up.

DO NOT wedge the screwdriver anywhere against the valve casing!!!!!!!

You can also insert a semi-round tool in the end of the stop arm against the spindle and carefully tap the valve out that way.

If none of these make sense, take it to a tech and ask them how to remove the rotor!

Eric
Sorry Eric, but don't tell anyone to "pry" anything! I fixed a lot of prying accidents in my 40+ repair carreer!
Best to just take it to a good repairman!
Kbiggs
Posts: 1167
Joined: Sat Mar 24, 2018 11:46 am
Location: Vancouver WA

Re: taking rotor apart

Post by Kbiggs »

After removing the screw, I insert a long, slender punch and gently tap with a rawhide mallet. No bent screws, and no wedged screwdrivers.
Kenneth Biggs
I have known a great many troubles, but most of them have never happened.
—Mark Twain (attributed)
User avatar
JohnL
Posts: 1595
Joined: Fri Mar 23, 2018 9:01 am
Contact:

Re: taking rotor apart

Post by JohnL »

I'm not a professional tech, but I've taken apart a lot of rotors. On many Olds rotors, the bumper is under the stop plate, so partial disassembly is the only was to replace it (and it generally needs replacing at very inconvenient moments),

Be careful with punches. Use the wrong punch (or the right punch incorrectly) and you can damage the threads. The punch should just fit into the spindle hole in the stop arm. If you're really ambitious, start with an oversize punch and file/grind/sand it to match the shape and size of the hole. I made one that fits most Olds rotors several years ago. It took some time, but it's been more than worth the effort in the long run.

I prefer a brass punch. Easier to size and less likely to scar things up. I also use a castoff rawhide chime mallet rather than any sort of real hammer.
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

so to clarify, instead of removing the linkage I should put a punch in the spindle hole with the linkage still on and hammer the valve out?
User avatar
Burgerbob
Posts: 4647
Joined: Mon Apr 23, 2018 8:10 pm
Location: LA
Contact:

Re: taking rotor apart

Post by Burgerbob »

If you have the linkage off (the stop arm), then you don't need the punch.
Aidan Ritchie, LA area player and teacher
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

Like this, correct?
User avatar
Burgerbob
Posts: 4647
Joined: Mon Apr 23, 2018 8:10 pm
Location: LA
Contact:

Re: taking rotor apart

Post by Burgerbob »

Yup, he's using the punch to both remove the valve and the stop arm at the same time.
Aidan Ritchie, LA area player and teacher
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

ok, I will try this.
bigbandbone
Posts: 588
Joined: Thu Jan 17, 2019 7:45 am

Re: taking rotor apart

Post by bigbandbone »

Make sure that the "punch" you use is a softer material than the rotor spindle so you don't damage the spindle.
User avatar
harrisonreed
Posts: 4595
Joined: Fri Aug 17, 2018 12:18 pm
Location: Fort Riley, Kansas
Contact:

Re: taking rotor apart

Post by harrisonreed »

Put a punch into the screw hole in the rotor spindle and smack it like you mean it. Make sure your hand is under the rotor to catch it. Use a rubber or rawhide mallet.

If it's not coming out, it's already damaged, so don't worry.


You can also use the screw -- some rotors like the CL2000 are made out of weak metal that a punch will damage. Just unscrew it an 8th or 4th turn and smack the screw.
bigbandbone
Posts: 588
Joined: Thu Jan 17, 2019 7:45 am

Re: taking rotor apart

Post by bigbandbone »

harrisonreed wrote: Tue May 05, 2020 5:31 am Put a punch into the screw hole in the rotor spindle and smack it like you mean it. Make sure your hand is under the rotor to catch it. Use a rubber or rawhide mallet.

If it's not coming out, it's already damaged, so don't worry.


You can also use the screw -- some rotors like the CL2000 are made out of weak metal that a punch will damage. Just unscrew it an 8th or 4th turn and smack the screw.
This is such bad advice in so many ways it makes my head hurt!
8parktoollover
Posts: 204
Joined: Fri Jul 06, 2018 1:44 am
Location: Modiin Israel

Re: taking rotor apart

Post by 8parktoollover »

I think maybe there is just a problem with my valve. Anyway my trigget became unsoldered ( unrelated to this repair) so i'll ask my tech to take a look
User avatar
harrisonreed
Posts: 4595
Joined: Fri Aug 17, 2018 12:18 pm
Location: Fort Riley, Kansas
Contact:

Re: taking rotor apart

Post by harrisonreed »

bigbandbone wrote: Tue May 05, 2020 6:12 am
harrisonreed wrote: Tue May 05, 2020 5:31 am Put a punch into the screw hole in the rotor spindle and smack it like you mean it. Make sure your hand is under the rotor to catch it. Use a rubber or rawhide mallet.

If it's not coming out, it's already damaged, so don't worry.


You can also use the screw -- some rotors like the CL2000 are made out of weak metal that a punch will damage. Just unscrew it an 8th or 4th turn and smack the screw.
This is such bad advice in so many ways it makes my head hurt!
You sure? The last guy I showed how to do this to was hitting the valve like a newborn chipmunk.

What about it is exactly bad? Been taking my valves apart for 17 years this way now, without issue.
User avatar
JohnL
Posts: 1595
Joined: Fri Mar 23, 2018 9:01 am
Contact:

Re: taking rotor apart

Post by JohnL »

harrisonreed wrote: Tue May 05, 2020 7:50 amWhat about it is exactly bad?
Not so much bad advice but conflicting advice. Using the screw is bad. Using a punch is bad. Pry the stop arm off. Don't ever pry anything. Smack it hard, but don't smack it hard.

All of the techniques mentioned work just fine most of the time. Anyone who takes rotors apart regularly will probably have either gotten into trouble at some time or had to clean up after someone else who did, and there's a tendency to shy from whatever technique led to that unfortunate situation.

Some general thoughts:

If you can't drive a nail straight, you probably shouldn't try to take a rotor apart.

If you do decide to use the "tap on the screw method", BY ALL THAT IS HOLY, DO NOT USE A STEEL HAMMER! Rubber or rawhide (I prefer rawhide, as I dislike the "bounce" of a rubber mallet). A brass hammer is probably OK, but why risk it?

Whether you're using the screw or a punch, start out with very light taps. If after a few taps things aren't moving, tap a little harder. Yes, you may end up having to smack it pretty hard, but the idea is to use enough force without using to much.
Bonearzt
Posts: 721
Joined: Thu Mar 22, 2018 7:40 am
Location: My Dungeon of Hell....Actually Texas
Contact:

Re: taking rotor apart

Post by Bonearzt »

JohnL wrote: Tue May 05, 2020 9:41 am
harrisonreed wrote: Tue May 05, 2020 7:50 amWhat about it is exactly bad?
Not so much bad advice but conflicting advice. Using the screw is bad. Using a punch is bad. Pry the stop arm off. Don't ever pry anything. Smack it hard, but don't smack it hard.

All of the techniques mentioned work just fine most of the time. Anyone who takes rotors apart regularly will probably have either gotten into trouble at some time or had to clean up after someone else who did, and there's a tendency to shy from whatever technique led to that unfortunate situation.

Some general thoughts:

If you can't drive a nail straight, you probably shouldn't try to take a rotor apart.

If you do decide to use the "tap on the screw method", BY ALL THAT IS HOLY, DO NOT USE A STEEL HAMMER! Rubber or rawhide (I prefer rawhide, as I dislike the "bounce" of a rubber mallet). A brass hammer is probably OK, but why risk it?

Whether you're using the screw or a punch, start out with very light taps. If after a few taps things aren't moving, tap a little harder. Yes, you may end up having to smack it pretty hard, but the idea is to use enough force without using to much.
Yup!! For me, rubber mallets do not supply the proper "shock" into whatever you're tapping on like rawhide or canvas mallets.

And as I mentioned, if you're not comfortable with supplying sufficient force, then you need to see an experienced tech!

And I stand FIRMLY with the advice I've given above!

Eric
Eric Edwards
Professional Instrument Repair
972.795.5784

"If you must choose between two evils, choose the one you haven't tried yet."
"Rather fail with honor than succeed by fraud." -Sophocles
Post Reply

Return to “Modification & Repair”