Where To Get 3" Netpots With Wide Lip
 

Trying to find some 3" netpots that have a wide lip on them, and recommendations?

I don't know if the lip on these are wide enough for you, but these are the type net pots I always use. I just make sure I don't cut the holes I put them in to big, and they have always worked fine for me. I generally just flip it over and draw the outline of the top lip, then cut it out about 1/8 of an inch smaller than the line. For cutting it out on rounded surfaces, I create a template the same way I mentioned, but on a thin piece of plastic (margarine or whip cream container lid etc.). Then it's easy to draw the line on any surface.

3" Net Cup
Net Pots

If you have a hydro shop near buy, you may be able to get them in quantity there and not need to pay shipping. A few years back when I was in Las Vegas I got a 100 pack of the 3 inch net pots for about $25.

A 3 inch hole saw probably won't work for 3 inch net pots, unless the pots have a exceptionally large lip. You'll want to cut the hole smaller than the baskets or they'll fall through. If you find a whole saw that will cut the right size hole for the baskets your using (so they don't fall through) that will work. Though most people seem to say that hole saws are difficult to use on rounded surfaces (like 4 inch round inch PVC or ADS tubing).

I have a lot of hole saws, but I prefer to use a rotary tool like in the attached pictures. When I need to cut a hole in plastic, that's the first thing I grab. It works great on everything I have done so far. However it didn't work that well on the blue 55 gallon drums I'm using for the Sub "T" system in my greenhouse. That was made of a very dense plastic, and the rotary tool worked on it, but kept breaking drill bits. With about 96 holes planed to cut, I thought about buying a adjustable whole saw (the only hole saw able to cut a 5 inch hole), but borrowed a jig saw that worked perfectly (and didn't cost me a penny to barrow).

P.S.
I bought that rotary tool at the swap meat 4-5 years ago for about $12. I didn't have a need for it at the time, just thought it would be a cool tool to have (especially at that price). But once I started building hydroponic systems, it has become the most valuable tool I have (other than my cordless drill).

The net posts listed as "heavy duty" have a wider lip then regular net pots and they DO really make a difference.

Absolutely. I bought 50 to test, and the perfect size hole saw for them is 2 7/8, when I put the pot in the hole, it literally slides in, no forcing, and there is zero play, none.