Upvc windows replacing old mastic

[borzio]

Hi, as the title says I'm having to re-do all the mastic/silicon round the upvc windows and on the joints of the upvc sills and upv internal finishes.

I've taken off the old mastic off with a chisel and stanley blade without damage (what a boring job that was) and need to mastic new stuff in all shiny and bright.

I have the tools: mastic gun, filler with antibacterial, and all my fingers ready to use to smooth the stuff, as well as the tee shirt I'll wear, that I hate most, to wipe said fingers on and annoy my other half.

So quick questions about preparing the surface:
As I say I've cleaned down all joints but in places can still feel a thin film of mastic....what is best to remove this and get good adhesion from the new stuff.
I have silicon eater from Toolstation, but don't know if that would leave a residue that I need to clean afterwards....
and I have Acetone, but would like to be advised if that would damage the upvc, or need cleaned up after use.
I also have UPVC cleaner from a previous diy job, but only used this to take off grime.
Lastly I have a box of Wonder Wipes donated to me the orther day, ..never used them before.
Any advice as always is appreciated, thanks in advance.

 

[KenGMac]

borzio, good evening.

Not too sure about total removal?

Could be argued that, if the old Mastic is adhering firmly then you may consider leaving on? mastic removal "Solutions" as you point out can have down sides in their removal???

As for using fingers to smooth of the Mastic, have a look on line for "Mastic masking Tape"?? this may assist, it prevents smearing of the new Mastic on to adjacent surfaces??

Ken.

 

[borzio]

Thanks Kent Mac, that's my worry that I use a 'remover' and then go into a loop trying to clean to a bare prime surface for the new mastic. I like the idea of the mastic masking tape as my mastic gun skills have good days and bad, cheers.
I always thought that putting fresh mastic on old wouldn't adhere....is the modern mastic now OK for doing that?