This looks like it will be the final version of the IP adjuster. It is not a modified 2500 part. I made a new one that can accommodate a larger bore. It's the same diameter as an R-4 type (3/8"), so the HP diaphragm has to be drilled out fit.
The spring seat is turned into the top of the bolt.
And the o'ring fits in the bore kind of like a new style USD balance chamber.
I have a slight concern about the brass adjuster screw where it contacts the HP "pin".
The original bolt in the 2500s is brass, and the contact point between the steel pin and the brass bolt doesn't show any appreciable wear. I'm wondering if the 1/4" surface of the adjuster screw will take any abuse from the pin. The point of contact is pretty broad.
The dull silver area is machined away on these, not worn away.
I'm fooling around with another IP adjuster that uses a readily available stainless 1/4 x 20 tpi setscrew (rather than the last iteration that used a custom made brass 12 x 24 screw). This doesn't help the average guy much, since a new bolt has to be machined, b/c the OEM 2500 bolt is too narrow to accommodate a 1/4" diameter.
Problem is, the coarser the thread, the less (touchier) adjustability you get. It might be a non-issue, idk. Threads are measured by threads per inch, so the lower the number, the coarser the thread. If you need finer adjustments, finer threads are better.
In this experiment, I've dropped from 32 tpi to 24, and now 20. Hopefully, it's manageable.
I'm going to be making several of these IP adjusters for my regulators soon. I just bought some brass bolts that should work after some machining. If anyone wants one, please PM me. Cost will be around $25, shipped.
I spent some time today on this. I cut a groove in a 1/2" long stainless steel setscrew for an o'ring, then machined one of the brass bolts I bought. I machined the bolt head on both sides to leave a thin hex head, drilled the bolt through, then tapped it for the 1/4 x 20 setscrew. Then I drilled a slightly bigger bore at the hex end to accept the o'ring as shown above.
The hex on these is not 5/8" but 9/16". If necessary, a washer will be used in conjunction with the bolt, but I can't see any problem if used with a new HP diaphragm.
Just to put it out there again, I'm asking if anyone has a satin exhaust horn ring for double diaphragm reg, or a junk Dacor two diaphragm regulator they'd part with, LMK. I have 2 R-3s that are missing the horn ring, and an R-2 missing the ring and a cover.
Slicing off the bolt head to thin the hex portion left enough material to make the retaining nut. It took some pondering to figure out how to drill and tap it once it was cut off. I had drilled the bolt through so the unfinished nut already had a hole in it, but not big enough. I ended up chucking it up in a 3 jaw chuck and mounting that on the mill bed. Then, it was cake.
Note the elongated second stage hole. There isn't much gasket surface around that hole, and the later models had only a sliver. Air wants to escape!
As noted in a dedicated thread, I set up for nickel plating and did a couple of these adapters as well as some other stuff. My plating prowess isn't awesome, but it's adequate at this point for corrosion control.
More experimentation will get better results.
Without making any judgements (yet), I noticed the guy who is selling new HP diaphragms for R-4s and 2500s is offering an HP shim that will RAISE the 2500s IP.
My experience with the 2500s is that IP is unusually high (160+ at 2250 psig), and getting the second stage to seat is difficult. When the IP raises at lower tank pressure, it is worse.
Getting the second stage to seat at 160+ is going to require a lot of spring pressure on the second stage lever which requires excessive cracking pressure to open the second stage, making a very unpleasant diving experience even if the regulator delivers more air!
I need to ask him what he based his theory on, and why he thinks raising the IP could make the regulator breathe more easily. Unless he's experienced 2500s with low IP, this shim makes no sense to me.
Here's what the USD puck cup mod on the second stage lever looks like:
The second stage volcano needs to be shortened to accommodate the extra thickness of the cup. The cup and second stage mods are permanent, but there's no reason to ever go back. New OEM levers are rare, and the mods allow owners to service their regulators.
Here I go quoting myself again. It just feels wrong, somehow....
Anyway, here's a photo of a 2500 series second stage lever that the soft seat fell out of, intact. From this, I'm assuming Dacor made a bunch of rubber buttons and glued them in.
It got me thinking that the cushions used in cabinets to stop the door from banging when closed. Here's what I mean:
These are 1/4" diameter silicone buttons that just might be glued in the lever as a replacement. No idea if they are hard enough, or will stick to the brass.