My DIY Pump
I made my own pump.
I know, I know. It’s not recommended..
Well, I’ve got a bit more fabrication ability than the average user.
PARTS: [McMaster Catalog Number]
2” ID Poly-carbonate tube $12.10 [8585K28]
1/4” x 3” x 3” poly-carbonate sheet $9.59 [85625K31]
Female quick connect $9.67 [5012K29]
Male quick connect $8.94 [5012K45]
FABRICATION:
The sheet was drilled and tapped for the NPT thread and then secured to the end of the tube.
The tube was then cut to length; 8” is about right for me, leaving enough for growth and to form the base.
Then, the sheet was trimmed and sanded to look nice and not be in the way.
I made an aluminum mold, on the lathe, to create a nice flare for the base the way that LA Pumps does.
I heated the mold in the oven to 300 degrees and also used a heat gun on the tube, itself, and pressed it down onto the mold.
It didn’t go as nicely as I thought it would, but it did get the job done well enough.
The hand-pump came off of eBay for about $20 and the tubing was sourced from a junk drawer at work; it was formerly a piece of junk stethoscope that was missing pieces.
The gauge on the pump came broken [starts reading at 15], so I have a replacement on order, but it functions for now.
I probably spent about 1-2 hours on the project.
If I were to do it over, I would drill and tap the end piece in the lathe as well as cut to diameter before attaching to the tube. I’d intended to use a flush-cut router bit to trim the end, but the poly-carbonate did not play well with the router.
I’d also experiment a bit more with how to form the flare. My mold worked fine and I’m going to keep it in case I ever make another chamber, but the technique of getting the plastic hot enough and then sliding it down the mold isn’t quite right.
The total cost of roughly $70 including shipping is well below the $200+ it would cost if I ordered from LA pumps. I honestly would have bought from them if it weren’t for the price.
Now, the various tooling and supplies that I already have on hand are a different story. If you have to buy tools to do it, then it’s almost certainly cheaper to buy retail.