HELP! Stihl 066 Build for Milling Questions

[Bob95065]

I have a worn out 066 that was given to me by a friend that had a saw shop near me. The saw was just plain worn out. The cylinder walls looked like mirrors from use. Air filter was clean when I got it.

My plan with the saw is to build it into a dedicated milling saw. I got a replacement cylinder for it. I plan on replacing the bearings, piston & rings along with anything rubber on it (seals, impulse line, intake boot, carb kit, A/V buffers).

The questions are should I go with a pop up piston? Base gasket delete? Mild porting? What are the get mods for a milling saw?

TIA,

Bob

 

[jacob j.]

I think I would skip the pop-up piston as those are a crap shoot in regard to being a good fit for OEM cylinders.

Just go with a new Meteor or OEM flat-top piston and a dual-port muffler unless you have the time and ability to do
port work. For milling, it's more important that the machine can run as cool as possible with the best air filtration possible.
Lots of people are milling with ported saws and it works fine.

 

[Ketchup]

The main thing is heat. Open the muffler as much as you can stand and keep you chain very well oiled. Keep the air filter clean and tight. Clean your clutch and drum often (after every day of milling would be good).

As far as porting, a wider exhaust will help get rid of heat. A tighter squish will make more. The lower intake will probably be good for the long difficult cuts a mill saw makes. Skip the popup.

A shiny finish isn’t a bad thing in a chainsaw cylinder. Your old jug may just need a little 220 hand sand to help the rings seat. I would definitely run the old jug over aftermarket.

 

[Rman!]

Agree with the above... IMO milling is about reliability. A fairly open muffler mod will keep the saw cool, and the repairs mentioned will keep it reliable. The 066 has plenty of punch for most mill aplications.

R.

 

[drf256]

As above. Heat is your enemy. Big exhaust, and point it up on the fly side and away from where you’ll be standing during use. A 4” piece of tubing works well. Someone here used a threaded pipe nipple so that he could add an extension when milling which I thought was pretty nifty.

Tight squish always good IMHO, gives better combustion. Too much compression is bad in a milling saw because of the extra heat it adds.

A “mirror” on the cylinder walls isn’t a bad thing. These aren’t cast iron cylinders, they are plated. I’d take an old cylinder with walls that look like mirrors anyday. Just give it a good scotchbrite hone. If you got a new oem cylinder, sell the old one on here if you are so inclined. If your replacement cylinder is AM, I wouldn’t use it. You’ll just be disappointed.

I wouldn’t use a popup, in fact I can’t think of a worse application for one. Try to keep static compression less than 180psi. Add a factory HO oiler to your setup. Use 28:1 to 32:1 as you mix ratio.

It’s all about oiling, heat, and getting the fumes away from you so you can breathe in all that good wood dust. Until you start milling, it’s just hard to conceptualize that. Whatever saw that you would deem a suitable size to buck a log with, add 50-100% to that for milling as a ROT.

 

[huskyhank]

If you want to hate milling, ignore the advice about getting the exhaust away from you. A nose oiler is a great thing, almost as great as a sharp chain. If a sharp chain is important on a standard saw, it’s twice as important on the milling saw.