Is one plastic pipe to brass compression fitting better than another?

[AlanB1976]

Hi all
I have plastic pipe going to a brass garden tap. This was done badly before (by me) and resulted in the fitting coming loose and wasting a lot of water. I want to do it properly now but am very nervous from the last incident and want to make a fitting that will not come loose. From my searches, I’ve read of 2 means of connecting plastic pipe to a brass compression fitting. The first using an insert in the plastic and the second using a plastic to copper pipe adapter, and then taking the copper into the compression fitting. So my question is, is one much better over another (i.e. less chance of it coming loose)?
Thanks
Alan

 

[Burnerman]

You need to cut the end of the plastic pipe dead square (there are tools for this), then use the correct insert for the pipe.
Use a copper olive for the compression connection and all will be fine.....the pipe shouldn't be scratched though.
Personally I prefer the stainless steel inserts for this, rather than the plastic ones but either should do. You'd maybe consider fitting a double check isolator inside the property at the same time?
John

 

[SandyLyon]

As Burnerman say's.

Don't use any jointing paste can use PTFE tape if needed.

 

[AlanB1976]

Thanks all. I bought the insert and soon will get down to doing the work.
How tight should I make the compression fitting?

 

[Phill Peck]

What make if pipe?
You know speed fit make different inserts for compression fittings

 

[Madrab]

How tight should I make the compression fitting?

If it's a copper olive then just a nip up is all that's needed, get it to bite then 1/4 turn.

 

[AlanB1976]

Thanks.
I have the insert that mentioned for compression fittings.
I don't remember the brand of pipe. It was dark grey plastic (or PVC?).