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Herman
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How I do it: Second stage removal

Sun Apr 23, 2017 10:55 am

Removing second stages from old DAs can be difficult at times. Many had the nuts peened in place and the support levers were bent. Both of these practices make the horseshoe lever and the second stage hard to remove. To make matters worse, the nut can be difficult if not impossible to remove without damaging the LP seat holder. Many are so badly peened and corroded that removing the nut results in breaking of the LP seat stem. Before Bryan had them reproduced, this was a death sentence for the old regs as replacements were hard to come by. This is how I go about removing a peened in second stage. It works the majority of the time but occasionally I still break one. It might not be the best way but it works for me, if anyone has a different technique, please share it.

Here is an example of a reg that has both the supports bent and a badly peened LP seat holder nut.
IMG_1301small.jpg
IMG_1305small.jpg

First I carefully bend the lever supports back straight with pliers, after you have them removed, double check they are straight and clean off any burs.
IMG_1302small.jpg
Hold the lever out of the way as best you can and with a thin screwdriver remove the 2 screws, at this point the lever will slide off. You can not get a full bite on the screws and sometimes damage them but replacements come with the service kit. At this point getting them out is all that matters. Often times I can work the lever off with just one screw and support removed.
IMG_1303small.jpg
With the lever and supports removed, gently unscrew the second stage. The threads on it are easily damaged so work it back and forth if it is hard to remove. Now comes the “fun” part, removing the nut. DO NOT try to remove it initially but rather screw it ON slightly then partially back off. Repeat this until the nut will screw most of the way ON, I know this is counter intuitive but what you are trying to accomplish is working the peen out of the brass nut threads. Trying to remove it at this point will just jam the 2 peened parts together; pretty much insuring you will break the LP seat holder. Remember, these parts are brass; they are fairly easy to break.
IMG_1309small.jpg
Once you have the nut screwed most (all if possible) of the way down you need to clean up the threads on the LP seat holder. For this you need a die. It is important to note here that these threads are 5-40 and not the more common 4-40. It’s easy to confuse the 2. Carefully start the die on to the thread and work it down as far as possible. Dies have 2 sides, one is intended to lead the die on so it has shallow partial threads, the other has threads that are more complete and come much closer to the edge of the die. Start with the side with the partial threads then repeat with the other side to get the thread cleaned up as much as possible. At this point the nut should come off easily. After you get the nut off and the second stage dissembled, run the die over the threads again to clean them up fully.
IMG_1310small.jpg
IMG_1313small.jpg
That should do it and remember to use the replacement nut that is in the service kit unless you just have to have the reg with all original parts. Hope this helps you accomplish this task..
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Herman

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Bryan
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 11:46 am

Another winner Herman! Thanks for taking time to put this together.
Doing it right should include some common sense, not just blindly following specs and instructions. .Gary D, AWAP on SB

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tripplec
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 12:20 pm

"Many had the support levers bent", is it not required to bend them back on reassembly? Will it stay in place if they are straight? All I have used are the hpr's.

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Re: How I do it: Second stage removal

Sun Apr 23, 2017 1:27 pm

Well done Herman! I wish I had had the benefit of this when I started! One thing I might add though. If one opens the cans and it looks like the last one to service the reg was Captain Ahab, I apply a good soaking of PB BLASTER penetrating oil and let the whole mess sit over night. It's great stuff and will work through 70 years of crud. Works great to free up old first stages too. I remember Bryan commenting several squares back about giving a first stage a dousing of this stuff and then covering the first stage with a rag so it doesn't become a morter in your shop over night. :lol:

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Herman
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 1:29 pm

There is no good reason I know of to bend the lever supports. I do not recommend staking the LP seat nut but it DOES (at least IMO) need to be secured some how. I use fingernail polish. It's easy to get, waterproof and stays on but if you put much torque on it, it shatters and comes off easily. Nylon lock nuts would be ideal but the stem is not long enough nor does it have a screwdriver slot to hold it in place so they are not a good option.

Jim, I use it too but try to avoid it if possible. It works great but stinks and is a bear to get off even with multiple washings. I can't get the smell out of the reg but then again I have an acute sense of smell. If you have something that cuts it off I would LOVE to know what it is.
Herman

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georgeaustin
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 1:42 pm

Excellent write up with pictures! Thank you!

swimjim
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 5:54 pm

Herman wrote:There is no good reason I know of to bend the lever supports. I do not recommend staking the LP seat nut but it DOES (at least IMO) need to be secured some how. I use fingernail polish. It's easy to get, waterproof and stays on but if you put much torque on it, it shatters and comes off easily. Nylon lock nuts would be ideal but the stem is not long enough nor does it have a screwdriver slot to hold it in place so they are not a good option.

Jim, I use it too but try to avoid it if possible. It works great but stinks and is a bear to get off even with multiple washings. I can't get the smell out of the reg but then again I have an acute sense of smell. If you have something that cuts it off I would LOVE to know what it is.
After 25 years in hardwood flooring and being a smoker until 1997 my sense of smell is somewhat compromised. I understand that getting the "smell" out can be a problem. But I figure all the parts are getting a hot bath afterwards anyway. My take is, it is easier to clean then it is to replace. On another note, if you think PB Blaster is bad and hard to remove smell wise, try Salt-X some time. That stuff works great to remove verdigris and it's paint safe for the labels and chrome safe.... but the stench! Holy man, that stuff is down right nasty!

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Bryan
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 6:29 pm

swimjim wrote: On another note, if you think PB Blaster is bad and hard to remove smell wise, try Salt-X some time. That stuff works great to remove verdigris and it's paint safe for the labels and chrome safe.... but the stench! Holy man, that stuff is down right nasty!
SaltX used to be my first choice but Salt Blaster is even better. I've never noticed any unusual smell to it at all....I wonder if it reacts different depending on the mineral content of the water it's mixed with??
Doing it right should include some common sense, not just blindly following specs and instructions. .Gary D, AWAP on SB

swimjim
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 8:43 pm

Back in a day I used to do ebay to acquire "new stock" for my meager collection. After getting ripped off by paypal on two occasions I gave up on ebay. Since then I have dealt with local Craig's listers or sellers on the forum. Because I am in the midwest, my Craigs list buys are usually pretty clean aside from regs from houses inhabited by chain smokers. The reg's I have obtained through the forum have generally been really clean.
Perhaps when we get together in Ohio in September, provided of course I am able to attend this year, we can take a reg reportedly rebuilt by an ex Navy seal/ Udt guy and do a tear down and rebuild as a group activity. With Bryan, Herman, Seahunt Jerry, Myself and others "kibitzing" it might be an educational experience for all in attendance. Just a thought.

Jim :wink:

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couv
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Re: How I do it: Second stage removal

Sun Apr 23, 2017 9:11 pm

I'm new to DH diving and maintenance so I've never had to wrestle with the above. But I always enjoy Herman's well thought out and written instructions. Using a bit of divergent thinking, one can apply some of these same techniques to different sorts of DIY.

Keep 'em coming, Herman.
A sincere THANK YOU to all at VDH who make this wonderful resource available and to all the thoughtful contributors.

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captain
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Re: How I do it: Second stage removal

Mon Apr 24, 2017 11:52 am

I have reconditioned broken eat holders before replacement were available from Bryan. I would drill hole through the seat holder using a lathe and # 38 drill bit and then use a 5-40 tap to thread the hole. Then use a length of 1/8" stainless TIG welding rod threaded 5-40 at both ends to create a new stem. I would also use a stainless 5-40 self locking nut, no need for nail polish or loctite. Corrosion issues gone.
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antique diver
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Re: How I do it: Second stage removal

Mon Apr 24, 2017 12:13 pm

captain wrote:I have reconditioned broken eat holders before replacement were available from Bryan. I would drill hole through the seat holder using a lathe and # 38 drill bit and then use a 5-40 tap to thread the hole. Then use a length of 1/8" stainless TIG welding rod threaded 5-40 at both ends to create a new stem. I would also use a stainless 5-40 self locking nut, no need for nail polish or loctite. Corrosion issues gone.
Great idea, Captain. Thanks for the tip. It can be applied to other similar circumstances where replacement parts are just not available.
The older I get the better I was.

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Creed
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Re: How I do it: Second stage removal

Wed Apr 26, 2017 3:00 pm

It works great but stinks and is a bear to get off even with multiple washings.
Usually, alcohol will strip the oily stuff off. Have you tried soaking the parts in rubbing alcohol overnight to kill the residue?
"Haul the sheet in as we ride on the wind that our
forefathers harnessed before us
Hear the bells ring as the tide rigging sings.
It's a son of a gun of a chorus" - Jimmy Buffet

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SurfLung
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Re: How I do it: Second stage removal

Thu May 04, 2017 4:23 pm

- Thanks Herman. I have been using a somewhat similar approach with respect to chasing/repairing the stem threads.
- I have done several DA 2nd stages by securing the seat from rotating using a forceps. The forceps goes thru the horn. I press the lever to lift the seat and create a gap between the lever and the top of the seat cap. This gap is where the forceps grips the unused bottom portion of the seat stem. With the seat stem secured from rotating, I am able to back the nut off the top of the stem... Essentially chasing the peened brass threads with the steel nut as it unscrews. Once this gets the stem disassembled from the nut and seat cap, I thread the nut back on and turn it back and forth thru the damaged threads until it spins freely.
- Some regs have required a very firm squeeze on the forceps to keep the seat stem from turning. I have never yet broken off a stem using this method... I do use a screw driver handle with a small socket on the end to grip the nut. So the force is all spin and no side stress that might occur with a wrench.
SurfLung
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