1/2 hardline to 3/8 for hvlp question

So, this could go in the garage forum too, if it needs to me moved so be it.
I'm plumbing my garage with 1/2 copper hard line, getting ready to paint a quarter on my project vehicle. I looked for 1/2 soft/flex line to go from the dryer to my devilbiss finish line 3. will using the 3/8 line I have be ok? What does every one here paint with?

What's the point of plumbing the garage with 1/2 when it has to choke down to 3/8 line?
I 'm asking this because doing my research on air compressor plumbing everyone said to use 1/2 or 3/4 copper line. I guess I assumed that there were larger flex host and couplers...what's the scoop?


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I did some pressure drop tests on my own and found that the
3/8" line wasn't much different than the 1/2".
the bottleneck was the couplers, look inside a 1/4" quick
dissconnect and you'll see the opening is about 1/8" dia.
As long as you have those, a 1/2" hose won't help.
I converted to 3/8" couplers that hook to a std 1/4" hose,
they made a big difference. the hole inside was twice as big.

so your using 1/4" flex hose to your hvlp gun? I have yet to spray anything out of my devilbiss fl3, but from what I've read isn't that too small? Im new to this still, so I'm probobly very wrong. I have 3/8 flex line and 3/8 couplers/disconnects, do I should be fine if 1/4 works for you...

So if I use 50' of 1/2 copper line off my compressor to the qc3 dryer, then 3/8 flex hose to my hvlp gun ill be ok, cfm wise? I know pressure will increase going down to 3/8 but cfm will go down. My compressor is a sanborn 80 gallon with 16.8 cfm..

Anyone paint with a set up like this?

I use standard 3/8" air line, those normally come with 1/4" connectors.
I use the 3/8" quick disconnects which fit up to the std air hose ends.
I would think the 1/4" airline would be to small but I have never used it.
Sorry for any confusion.

Isn't it more about volume, psi remains the same.