tree monkeys 2153 deluxe

[tree monkey]

the stock port numbers were
in 146
ex150
tr 110
bl 20
sq 33
bg 20
removed the base gasket and got
in 150
ex 146
tr 106
sq 13
bl 20
after cutting base and squish
in 158
ex 133
tr 87
bl 23
sq 17
these numbers may not be exact but, good enough for what I need to know.
there all going to change anyway.

 

[Trx250r180]

Scott- Do you cut the base and flange on a lathe?

Horse shoe rasp

 

[tree monkey]

Scott- Do you cut the base and flange on a lathe?

yes, I had a pic but it's lost somewhere.

 

[tree monkey]

Old......and slow.

I still do it this way for a reason randy.

 

[tree monkey]

this is a 390 set up to cut

 

[tree monkey]

after cutting the sq I always put a ring all the way to the top to insure that the piston has the clearance it needs. take care in doing this so you don't break the ring.

 

[tree monkey]

it' not the best pic, but it shows that the heat shield has a larger port opening then the cylinder. I match the sides and bottom, but raise the top more.
you would not want to do this to a pipe saw.

 

[tree monkey]

with the heat shield on the muffler, you can see how much I raised the port. port match the muffler to the heat shield.

 

[tree monkey]

I put the sanding mandrel in the cylinder and mark the stock port with a fine line ever sharp pencil. I then measure port width.
the bore is 1.740, 65% of the bore is 1.131. that's what I want. it's at 1.004 stock

 

[tree monkey]

I cut a divot in the center of the port window and check port timing. I repeat this until I get to 2*short of my target duration. I work one side at a time, widening and blending to the center. about .060 wider. I put the mandrel back in, if i'm working on the right side , I line up the mark to the port on the left side. once I get the shape I want, I mark the right side. then repeat the process on the left side. all this is done with a hog.

 

[tree monkey]

a little more work with a double cut and a diamond cutter and this will be good. slow and careful till I hit my target width and duration.

 

[RedFir Down]

Awesome thread Scott, you have hit on a lot of good points!!! Thanks for sharing!

So how have you been? Feeling better?

I seriously considered flying out there for your firewood cut a month or so back. It would have been a pleasure to help out, meet you and the others!! I wished it would have worked out.

 

[CR888]

Thanks for sharing Scott, you are a builder that keeps fairly quiet on AS.....which is not the norm for most builders. I like that you are doing things quite different to others and like many others would love to have the privilege of a 'treemonkeyed saw' in my stable. I like what you do to the dolmar 7900 cranks.....clever. I was wondering with the added mass/weight on the crank does is kinda store power like a weighted flywheel? I realize its primarily done to raise comp but l wonder how it affects things while cutting.

 

[Milkman31]

I like a good build thread!! Thanks for your time.

 

[WKEND LUMBERJAK]

In before all the arguing starts.

love it.

 

[lwhaples]

Watching with huge interest.Thanks for sharing.

 

[Duane(Pa)]

Thanks for taking the time to post this. I love to see how this stuff works.

 

[Stihl Livin]

I'm going to have to run this saw next time I stop out. Maybe it will be for sale too.

 

[MarcS]

The real gain on porting a WH model is half the warm up time and an extra 10 degrees on the handle temp. Better ship this one out with a pair of welding gloves[emoji2]

 

[tree monkey]

thanks for all the positive replies guys