Socket for old shower valve bonnet needed

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 8:40 PM

I'd like to service a shower valve in a 1957 house with original plumbing.
The bonnet nut uses a round boss 7/8" in diameter with two flats milled
in it about 3/4" apart. It'd be a cinch if the valve stuck out of the wall,
any open-end would fit. Unfortunately it's recessed about an inch behind the
tile, so a socket is reuquired.
All the wrenches I can find fit hex nuts, does anybody know the correct name
for the required tool? From time to time "nuts" like this have crossed my
path, but I've never encountered one used in a position that requires a
socket to grab it.
At this point I don't even know what to look for. Correct terminology would
help a great deal.
Thanks for reading, and any guidance.
bob prohaska

- C
- Carl
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 8:52 PM

Big question is how big is the hole in the tile? If it's big enough you could get a crow's foot wrench in there, or a sink wrench (think right angle pipe wrench on the end of a T handle). Google or search amazon.com for pictures of both. Or make a socket by milling a deep 3/4" wide slot in the end of a piece of 1" square bar and turn it with a big adjustable wrench.

- L
- Leon Fisk
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 9:05 PM

Too funny Carl. My post sounded like an echo of your's :)

- J
- Jim Wilkins
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 9:11 PM

Dos it back up to a closet where you could cut an access hole and fit a cover?

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 9:43 PM

Nowhere close to big enough for a crow's foot. I'll have a grind out some of the tile and grout to get a relatively thin socket on the bonnet fitting.
If I just hammered a pair of flats on a 7/8" ID tube it _might_ work, but any wrench I can make will be a worse fit and weaker than the worst wrench I'm likely to buy. If I damage the valve it'll mean taking out tile, that could easily turn into a bathroom remodel 8-|
There's nothing particularly special about the house or the way it's built, I'm sure the valves were common before the advent of single-control valves. If I knew what the needed wrench was called I'd have a chance of finding one. Terms like "2 flat socket" and "2 point socket" find nothing. "Valve bonnet wrench" finds many matches, but they're all hex.
A search through McMaster-Carr catalog 117 found nothing even close. That could mean the valve is rare, but nore likely it just means the valve is a purely residential product.
Thanks for writing,
bob prohaska

- D
- dcaster
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 10:01 PM

If I wore going to make a special tool, I would think about using a deep socket and a nut that fits the socket. And modify the nut by cutting it so it converts the socket to what you need. THen hold the pieces of the nut in the socket with glue
Dan

- J
- Jim Wilkins
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 10:46 PM

If you make a socket by milling a 3/4" slot in the end of round stock, there's no need to match the 7/8" circle at the ends, the slot can just be longer.

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 10:51 PM

No, shower and tub are back-to-back, plumbing is in the common wall and both surfaces are tiled.
I suspect a lot of these valves were used in the '50s and '60s and quite a few of them are still in service. If I knew what they're called it's likely I could find a wrench, or at least what the wrench looks like.
I don't have any machine tools except a lathe, so cutting a pair of accurate wrench flats will be a "file and fit" proposition. Using the lathe to form a pilot hole that fits on the valve stem/bonnet will ease the fiting problem somewhat, but a purchased wrench of the correct type is much less likely to damage the valve.
Would posting a photo of the valve bonnet help with identifying it? I thought somebody would recognize it by the description.
Thanks for posting,
bob prohaska

- C
- Carl
  
  Contact options for registered users
posted
3 years ago

Mon, Dec 10, 2018 11:02 PM

:-)

- J
- Jim Wilkins
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 1:14 AM

You can mill on a lathe, as long as the cutter in the chuck only pushes the work on the carriage downward.

- W
- whit3rd
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 1:27 AM

Yeah, that's do-able; just turn a thick disk, mark center and scribe lines at 3/8 inch either side; hacksaw through half or less of the thickness near those lines, and grind out the middle.
Then fine-tune with a file until it fits. Extra credit, weld a pipe onto the disk and make a T-element on the other end of the pipe for a handle.
Actually, welding a couple of bars onto the endface of a pipe wouldn't be too bad: clamp a right-thickness chunk between 'em to keep parallel.

- L
- Larry Jaques
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 4:37 AM

That's the problem with posting a question about unseen hardware here. Like calling the body shop and asking "How much to fix my fender?" LOL Sounds like what I call Double D, but I've never seen one on plumbing, only on electronics and front wheel spindle washers.
The worst part about plumbing is that the guy who installs this crap never has to disassemble it 10-50 years later. If only they'd put anti-sieze on it in the first place...
Will calipers fit down in there to get good measurements to mill one up? Find the Old Guy at the ACE near you and ask him, or an ancient plumber.

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 5:44 AM

The idea of welding wrench jaws to a handle is a good one that I didn't think of. I do have a welder, trying to make a wrench would be an instructive exercise in any event.
In the ( probaby vain ) hope that somebody will recognize the valve's maker or the needed wrench type a few photos have been put at

formatting link

For scale, the long threaded part is 5/8" diameter, the flats are about 3/4" apart and the OD of the boss is 7/8".
If the manufacturer is known it'd maybe let me anticipate what sort of seals are required before I take it apart.
Thanks very much!
bob prohaska

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 6:01 AM

Double-D looks right in the photos, but the few examples I can find on-line are all much too small. Still, it's a start, I've never seen the term before.

Yes, that's one of the larger questions. I've no idea how badly stuck the threads are.

The one ancient plumber I talked to said "You've got a problem". All the rest seem to be dead or retired. My calipers won't fit, but I can get them close enough to have a pretty good idea of the size. The flats are just under .750 across, the boss OD is just under .875" across, the long thread (holds the decorative cover on) is close to .625" in the photos at

formatting link

Thanks very much for the double-d tip!
bob prohaska

- J
- Jim Wilkins
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 12:13 PM

It may have been assembled with an open-end wrench before it was placed in the wall. I'd look into modifying a cheap 3/4" or 19mm deep impact socket, perhaps anneal it, drill / bore out the ID, mill (grind) clearance notches across the end and turn it with Vise-Grips. -jsw

- B
- Bob Engelhardt
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 1:29 PM

You are not ever going to find a ready-made wrench for that. The welded-up suggestion is a good one. Another approach might be to use a die grinder to cut the other 4 flats on your nut & turn it into a hex. The nut being brass would make it more easily done.
However, fitting a wrench to that nut is likely to be only the first problem in fixing that shower. After 60 years, that nut is not going to come out gracefully and there's a good probability that something will break in the process.
The right way to fix the valve is to replace it. I know, it's in a tiled wall, but they make large plates to cover the hole. Google/images "remodeling shower cover plate". Ask This Old House did a segment on it:

formatting link

You might be able to fix the old valve, but you _know_ that it won't be the end of it. Do it right, replace it, and be done with it.

- J
- Jim Wilkins
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 1:49 PM

I've partly disassembled a tree of old brass pipe from a contractor neighbor's scrap pile. Some of the pipe-doped fittings unscrew fairly easily, others require enough vise clamping pressure to crush the pipe.
The pipe can be machined into 1/2" ID pivot pin bushings that withstand more force than Oilite.
-jsw

- L
- Leon Fisk
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 2:52 PM

I've got the same or very similar bathtub faucet. Mine wasn't mounted so deep and you can fit a spanner wrench on the bonnets. Couldn't get the seats out though. Didn't want to break something trying any harder to turn them. Those two flats on the bonnet for a wrench are pretty common or at least it used to be. For instance Streamway as shown here:

formatting link

is pretty close. You can download the whole Danco catalog here (huge! 180MB):

formatting link

it has good pictures for a lot of old stems in it with manufacturer names. Streamway has a few good examples on actual page 38 of pdf. I couldn't find any special sockets to fit that shape though. Also a nice schematic on page 5 detailing all the proper part names...
On my bathtub I just replaced the washer, packer, escutcheon nipple and escutcheon. Used a 6-flute countersink to touch up the seats. Maybe a conical grind stone too. Probably by hand or really slow in VSR drill. Been over 10 years now, don't remember the details for sure...

- E
- etpm
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 4:42 PM

I would tell you to call a plumbing shop but you probably already did. There is a shop I go to rarely for old stuff and they would at least know if the tool is available. There is another thing you should do along with this repair and that is install valves (AKA stops) in the plumbing before the shower and tub valves. This way you only need to shut off water to those valves and not the whole house. If you take that valve apart and everything goes to hell with the valve you will be happy that you installed the extra stops. Of course this assumes you can get access easily to the plumbing under the floor. Eric

- B
- bob prohaska
  
  Contact options for registered users
posted
3 years ago

Tue, Dec 11, 2018 5:32 PM

Just sent an email to Danco with a link to the photos, maybe they'll reply. In the meantime I'll download the manual to see what I can learn.
Thank you!
bob prohaska