parrisw
Tree Freak
Why not?
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Why not?
tree monkey
Addicted to ArboristSite
i wanted to know if you know why? it's been talked about here before. i understand what it does. but how did you come up with 2 degree
parrisw
Tree Freak
I did some searching and came up with 1-2° angle for 2 stroke squish bands. And as well I asked Eric and he cuts his at 2°, so that's why I did it, not based on any of my own experience, this is all new to me, I think it has to do with forcing fuel air to the center.
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tree monkey
Addicted to ArboristSite
what i've read says it depends on bore stroke and width of the band. traped comp also
parrisw
Tree Freak
I'm sure there are many variables. It just makes sense to me to have it tapered, if it were flat or tapered the other way, unburned fuel/air could get trapped in the squish area.
It would also depend on if the piston is domed or not, if you had a domed piston, you'd want the taper 2° more then the dome taper, now I know not many saws had domed pistons, just something to think about.
tree monkey
Addicted to ArboristSite
tw got into the subject pretty deep some time ago. good read if you can find it
parrisw
Tree Freak
Ya. I miss having him around. He's a good dude, was always willing to help.
Did he post about it here on AS, or on the other site that's now gone?
tree monkey
Addicted to ArboristSite
i think here
parrisw
Tree Freak
Cool. A searching I will go.
Machine work is all done. Just did the cyl base this eve. Squish now is at .023, it ended up there, so I figured I'd leave it there, don't want compression to get out of hand.
Post machine work numbers.
EX 97.5atdc 165dur
Intake closes 76.5ftdc 153dur
Transfers 121atdc
Blowdown 23.5
My thoughts, ex will stay were it is, just widen.
Intake maybe bring up to 155-156dur close to 80ftdc
Transfer maybe raise up to 119?? little unsure about the transfers still.
that would leave 21.5blowdown
Now the Million Dollar question is how do you this w/o a lathe?
parrisw
Tree Freak
You don't.
You do, if you have someone make the tools for you you can. Hell, I've cut squish bands and cylinder bases with sand paper and elbow grease.
komatsuvarna
Arboristsite MVP
:monkey:
komatsuvarna
Arboristsite MVP
Machine work turned out real nice Will. Makes me wanna lathe...maybe one day.:smile2:
You decide what timing you were going to shoot for yet?
You decide what timing you were going to shoot for yet?
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parrisw
Tree Freak
Too each their own, I would never do it that way. especially on Husky cylinder where the bottom protrudes into the case, I've seen people cut holes in wood that the cylinder fits in and put sand paper around the hole and sand away. Sorry but I like things accurate.
Don't know. Was thinking of leaving it alone and see how it runs, ex will stay the same for sure, if anything the intake can come down a little, and transfers up 2°, but its so close now, I may just leave it and try it, just widen all the ports though.
NORMZILLA44
Addicted to ArboristSite
Good job I to am impressed with your machine work Will!
parrisw
Tree Freak
Thanks Norm. It's fun and frustrating at times. I love learning new things, especially mechanical things such as this.
My grandma once told me when I was young, that I have a very mechanical mind, if that makes sense.
parrisw
Tree Freak
Eric also helped me do a little brainstorming about numbers on this. And its real close to what we talked about.
Its easy to go back in for more, but its all but impossible to put it back.
Will "I" would much rather go back in a new modal saw 3-4 times and make adjustments that go crazey the 1st time and wonder what it may have ran like "IF" I had done this.
I have a 2188 on its way so we can compare notes later on if you like.
