Cheap sightglass fitting...

I'm sourcing parts to build my own sight glass and it seems the most expensive part of thing is the pipe to tube compression fitting. I've come across this... http://www.usplastic.com/catalog/item.aspx?sku=60424&catid=676 Does anyone see a reason this wouldn't work?

you would be just pushing the heat tolerance limits of it. if you have any heat radiating past the bottom of the kettle from your burner it would likely still melt. if it is only rates to boiling temp (212*) that doesn't give you much margin for error on it melting.

IMO

I used a 1/2" to 3/8" bushing and wrapped Teflon tape tightly around the polycarbonate tubing until it was built up to about 1/8" and carefully threaded it into the bushing. The stainless bushing was $4.00 compared to a $30.00 stainless compression fitting. The advantage of doing it this way was not having the compression fitting shortened the assembly allowing me to read lower volume. Never leaked a drop after 12 batches. I bought the tubing in 4' section from McMaster Carr and cut it into 3 sight glass tubes very cheap.

McMaster has a decent selection on those plastic compression fittings. Mine is rate to something like 250°F. I bought 5 for seven dollars. They are however 1/2" NPT male thread and not 3/8". Here is the part #: 5016K446 - it is for a 3/8" OD Tube which I also sourced from McMaster (Part #: 9176T12)

Just do THIS, it's what I did and seems to work great! I like the larger tube as well, makes it easier to see the liquid level.

I just used high temp barb fittings.... heated the tube to soften it and pushed it on, in shrinks as it cools and is water tight.

Love blaze379's design there with the return to the kettle. No wort wasted there!

I did this one out of mostly copper fittings.

https://www.homebrewtalk.com/f51/diy-sight-gauge-110185/

The Borosilicate glass tube was not that much...got it a McMaster Carr

just thread the end of the tubing. I did this on my setup and it is holding up swell!!

here is a link to the threadhttps://www.homebrewtalk.com/f51/cheap-sight-glass-229974/