Flux viscosity

[alparent]

I'm making my first batch of DIY soldering flux, using pine sap.
I've never used liquid flux before so I have no idea of the viscosity I should be aiming for?

Any help would be greatly appreciated.

[Mark Hammer]

The commercial stuff is like 10W30 in thickness.  I can bring you some tomorrow.

DIY flux?  After I accidentally knocked over a bottle in my office, and it spilled on the wall-to-wall carpet.....not for me, buddy, not for me.

[alparent]

If you don't mind...that be great! 

[R.G.]

I personally like it much thinner, about like milk. I put it on with Q-tips and toothpicks when needed. Cheap artist's paintbrushes work well to.

The best bottle is probably a thick based glass one, all the weight in the bottom like an old India-ink bottle. Er, if you're too young to remember those, either write me or write me off. 

[alparent]

The one I've made seems to evaporate to fast.
I think I've diluted it to much?
As soon as I apply it to the board....the denatured alcohol evaporates.
I think it should stay wet as I'm soldering?

Maybe using Isopropyl alcohol it wouldn't evaporate so fast?

[R.G.]

The alcohol is just a solvent to get a thin layer of the actual flux on the PCB. If you're making the right kind of stuff, the alcohol plays no part in the action at all, and you want it to "dry" to a slightly tacky film.