Home owner MS170 Versus pro saw MS200 contest

[nimblebee]

Another Perfect Day in Winter Wonderland :-) 7 F and described as "warmer than yesterday" with a 7 degree rise to high of 14 degrees, being described as a "warming trend," before possibility of more snow tonight.  lol
Fair chance tree service company I work for's not going to be calling anybody in to work today, so looks like I'll get to spend some quality time with my "B.S.170+" saw build 8)
One thing I could do today is walk down to the creek and go along through the woods and see if I can find myself a "calibrated log" lol   Doesn't need to be calibrated, since all timed measurement's going to be subjective anyway, but there's no purpose in porting a saw, if one can't perceive a significant difference in performance.  "A difference which makes no difference is no difference." -Alfred Korzybski
I've been reading on forums that people that use J-B Weld inside their cylinders sometimes have the J-B Weld come loose, but in cases that I've seen reported, J-B Weld gives no harm and merely burns up.  Going from this, it would seem like J-B Weld would be ideal for experimenting? idk  
The idea is to change one thing at a time, test & make measurements with "calibrated log" and then in notebook, record findings and decide what changes to make, all for the purpose creating a more powerful, useful, work saw.  To that end, have purchased/set-up chainsaw record-keeping notebook.
Outside the box thinking:  using J-B Weld to find the perfect dimensions for my particular saws strongest performance.  This information I could then use casting myself a completely new cylinder (yes I can DIY metal casting and also nikasil coating ... it's not that hard ... plenty of YouTube videos for those that enjoys studying and learning new things ... DIY "NIKASIL" Two Stroke Cylinder plating P1 - YouTube).
How to go about using J-B Weld?  Anywhere don't want J-B Weld to stick, use Vaseline or some other mold release agent to prevent adhesion.  Take for example a pop-up piston (or the opposite: insert to reshape the top of the cylinder to give ideal dimensions), could use Sculpey, JB-Weld or any other substance to create ideal chamber dimensions (including squish, angles, shape etc.) used inside on top of the piston to compress the J-B Weld against cylinder's top.
This could create a huge mess (careful in preparing things ahead of time for application of JB Weld) without adequate provisions!  If creating core for casting cylinder insert,  place plastic wrap in cylinder head to act as barrier to adhesion, also use mold release agent like Vaseline.  Arrange for any excess to escape out open spark plug hole (being sure such can escape without hopelessly JB-welding insert inside cylinder lol)
Everything performed carefully, place engine block with JB-Weld inside shop oven (not recommended for significant other's kitchen appliance! lol) on a low temperature and cure J-B Weld in short time period (Don't be lazy! do your own search ...Google search will be your friend finding out how this is accomplished lol).
What's one end up with? Exact shape needed for cylinder insert making piston have correct squish (many builders like .020 or thereabouts), multiple angles for squish band (some builders prefer angles), and (what's believed to be) ideal chamber shape and size for application.
How you use this core? Depends upon what your goals are.  If you're into destructive testing, leave out one layer of plastic wrap "shielding/mold release" & adhere JB-Weld inside cylinder's head for testing purposes.
If casting shape for pop-up piston?  Greensand-cast aluminum insert to affix atop piston.  Experiments going this route, it'd be worthwhile using donor engine block as casting material, insofar as metal's already properly alloyed for the purpose (preventing weakness/impurities use some form of flux).  Home diy Nikasil plating for insert might prove beneficial? idk
Going opposite route & making insert to change shape/size of compression chamber and leave Piston OEM? Use J-B Weld core to cast an aluminum insert to attach inside cylinder to cylinder's head.  Depending upon how you decide to attach insert?  One could choose method allowing provision for changing out inserts during experimentation.
All of this of course, means nothing without a "calibrated log" to test against.  Experiments prove nothing, unless one has significant, visible, & repeatable results comparable from one experimental change to the next.  
That's the purpose of chainsaw's experimental notebook: keeping track of results & making everything convenient/organized  :-) lol   What's not to like?




I'm using foot pedal from my sewing machine, so providing multi-speed,  hands-free, easily-controlled Dremel tool.  Bright positional sewing light helps visually down inside cylinder:-).  
There's 90° angle Dremel attachment to reach where restricted access for straight shaft tool.