I'll add to the recent spike in conspiracy theories... One of the advertisers complained to the mods that we were giving away free directions to make something they sell and so the mods "made it go away"... or something like that.
Anyways I've now made two, no videos but I took a few pics and have several observations.
First off I've found it easier around here to find the parts in schedule 40. A little heavier, but several places have the flat caps (and they are a bit deeper, more on that latter) requisite for this job.
The biggest problem I have is getting a good glue bond at the outlet. The 1"x3/4" slip has barely any purchase in the drilled hole through the side of the cap. Sch 40 is twice as thick (or nearly so) as the sewer pipe fittings (SDR 35 or 17? not sure) at any rate, there is more purchase for the glue. The other main issue I have is that the fittings I can get locally (both sch 40 and sewer) are relatively shallow... about 2" deep. The check valve is a little over 1.75" (1.5" ID) and the coupler used to attach the check valve to the 1"x3/4" slip is 1.5". This doesn't leave much room for a glue seal between the barrel of the pump and the hole for the check valve assembly (about 1/4"). So I sanded down a flat in the side of the check valve as much as I could without damaging the inner valve it's self and got another 1/8".
I did some research online and found several companies making flat bases that are 3" plus deep. If I were to do it again I'd find those, either locally or online. I'm guessing I could have gone to NW pipe, or an irrigation wholesaler and found what I needed, but I couldn't find those deep fittings at any retailer in BZN. It would be well worth the time to get at least one for the base (the top won't matter, shorter is fine). Both pumps bleed off pressure and in both cases it comes from around the outlet fitting and that thin joint right above it. This pic shows how little purchase there is at this location.
Another issue I noted was in the star (spider) portion of the plunger assembly. The first one I made, I admittedly eye balled when drilling it out, and used a larger bit - 1.75" OD hole saw if I recall. It left fairly spindly legs but it works just fine with the a doubled up gasket (2x1mm adhesive backed foam stuck together). I tried using a 3 ply gasket and it was too stiff and bulged that leaked badly.
One thing I did slightly differently than unlucky was that I used a set screw to hold the plunger shaft into the 1 1/4" flat base (instead of gluing it), that way it's easier to take apart and replace pieces if needed. The pic below illustrates that concept and shows the bulge in the thick gasket from the side.
FWIW, I made all my flat pieces out of 1/4" HDPE as I have a bunch around. Something stiffer might be better but the only place I see a problem is at the star. The second star I made, I just left more material (used 1 1/2" hole saw) and it worked great with both gaskets (2 and 3 mm).
Here's a comparison:
and the finished sch 40 project (the second one I made with sewer pipe).
The sch 40 pump is definitely heavier, but I'd probably stick with that material down the road for me - just more durable. I'll use both pumps a bit and maybe my opinion will change but I just tend to err on the over built side.
The last thing I found was in the first pump I used a hole saw to cut the hole in the top of the upper fitting (for the 1 1/4" plunger rod). I tested it in a piece of plywood and it seemed like a good fit, but once it was done, there was a bit more play than I'd hoped. So the second one, I used the adjustable hole saw and cut it for a snug fit, then rat tail filled it out just a little bigger. The tighter fit seems to stop some of the squeaking I get from the plunger in the looser version... nothing major, I just think getting that hole just the right size is worth the effort. Sorry no pics of that issue.
Again, thanks unlucky for originally posting this build. I really like this kind of project and I always learn a lot.