by RuddyCrazy » Thu Oct 06, 2022 5:48 pm
G'Day mate,
If you are going the build route and lets say you go 4" with 3" site glass's then a 3" or 75mm holesaw is the best tool to use, just drill into the 4" with the holesaw then I used the holesaw to drill thru some 3" thick plywood. Then using a wood saw cut one side thru to the 3" hole you made. As I do have a bridgeport mill I just lined up the wood jig then clamped it down to hold the 3" pipe nice and tight and slowly lowered the 3" holesaw thru the pipe to make the mating fitting on the 4" which will be a spoton fit. Then carefully applying flux so none of it dribbles one can soft solder the joint quite easily with gentle heat.
As you don't put in a location we don't know where you are and if you want more tips just open a build thread and ask away any questions.
Cheers Bryan