Stihl 084 build

[Stump Shot]

What are you checking with the level?

Good question. If you'll take notice of the tool holder for my boring bar is an older style that needs to have the height set every time I use it. Since chainsaw cylinders almost always have a casting line running smack down the middle of them and my lathe has been leveled in with a .002" machinist level, I can plumb the exhaust port and set the casting line at 90 degrees and have a visual clue as to where the middle is and therefor center is to set the boring bar cutter to. It's just a faster way with less steps for setup.
Now at some point here in the relatively near future, I will be updating this to a more modular quick change type tool holder that only needs to be set the one time and can therefore be implemented in an easier manor and eliminate this step.
Along with this new cutting bits and boring bars with changeable carbide tips will also be acquired to go along with. Having just recently broken my favorite lathe bit for cutting cylinder bases spurred this on and newer styles had to be ordered already setting this into motion, one set is already here and another on the way and more to purchase as I go along that I've already eyed up.

As a side note for anyone not understanding something in the series of pictures I've posted, please ask as it's not easy to explain every last thing along the way when trying to upload them from my phone, as I would just as soon type out words on my computer keyboard instead.

 

[Stump Shot]

AS far as the porting goes, it was done in a manor to build torque as one can only work these behemoths so fast before you knock the stuffing out of them. Without revealing numbers as they were shared with me, I can say the only thing really uniquely different that was done is the little hangy-down thing in the intake port was removed as it wasn't need any longer to retain the lower ring that is no longer there. And that really being its only function and not a super-secret Stihl performance item.
I do like starting the process on the porting fixture. Especially the upper transfers, having everything rock steady and level makes the job easier and more accurate for myself.

 

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More sub assembly work...
Carburetor rebuild.

 

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Bagged up to stay clean and ready when needed.



IPL's are handy for a reference.

 

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Muffler was already modded and sent to @Glock37 for high temperature powder coating, including the large @tree monkey deflector.

 

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With a new spring pack, the starter was finally put together. Stens true blue line one of the few non genuine Stihl items on the build, but one I trust completely.

 

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Clutch cover coming a little bit farther along.

 

[legdelimber]

How'd ya get stuck with that Armstrong (crescent style) tool post?
Seemed like every time I encountered one, the center bolt was wallered into the shape of a center punch from being on an angle against the (up tilted) tool holders.
That or it was bent from walking sideways when someone used a pipe to tighten it on an angled tool holder.
You couldn't just put a block/plate underneath to level them, since None of the different tool holders never seemed to be anywhere near to the same centerline height

 

[Stump Shot]

How'd ya get stuck with that Armstrong (crescent style) tool post?
Seemed like every time I encountered one, the center bolt was wallered into the shape of a center punch from being on an angle against the (up tilted) tool holders.
That or it was bent from walking sideways when someone used a pipe to tighten it on an angled tool holder.
You couldn't just put a block/plate underneath to level them, since None of the different tool holders never seemed to be anywhere near to the same centerline height

A bunch of tooling came with the lathe, so the South Bend tool post and holder fit a 5/8 carbide tipped boring bar and it works well. Much better in fact than the modern one I broke way back when. I guess I'm slow to adapt to new things when old ones are still working for me. That and it seems that there is almost always a more important much needed item to keep you going that gets your money and attention before nicety's can be had.
Like I said though, it's on my radar and to do list and I'll get to it eventually. A recent good example, last night my 6" dial caliper went haywire on me and is need of replacement. The batteries dead in my digital back-up, I had to acquire new batteries and am now shopping for a new dial caliper as it is what I am most used to. I use the tail length feature mostly for measuring port heights after machining and making new depth gauges for porting. So, you can see how it goes, I need that more than a new quick change tool holder set at the moment. And it goes from putting out one fire to the next, and the next, and...

 

[legdelimber]

Stumpshot, I hear ya!
Over the years, I've had access to a couple of bench top Southbends.
Always flat belt driven.
Somehow that crescent piece is always missing whenever someone asks if I'll help get them get their recently inherited machine going.
Ain't it amazing just how quickly the tooling costs start adding up.

Funny that I just never picked up any of the electric calipers. Just didn't need the electronic data management (back then).
8" Mititutoyo dial cal just seemed to handle most of the parts I worked with (on the job).

 

[Stump Shot]

Stumpshot, I hear ya!
Over the years, I've had access to a couple of bench top Southbends.
Always flat belt driven.
Somehow that crescent piece is always missing whenever someone asks if I'll help get them get their recently inherited machine going.
Ain't it amazing just how quickly the tooling costs start adding up.

Funny that I just never picked up any of the electric calipers. Just didn't need the electronic data management (back then).
8" Mititutoyo dial cal just seemed to handle most of the parts I worked with (on the job).

Funny you mention that, I just purchased a Mitutoyo dial caliper last night. Vintage of course. Was between it and a Starrett and I just kept coming back to how clean and clear the dial face was and no engraving of someone's name etc. on it. It looked unused really.
I learned over time and repeat failings of batteries in the electronic one I have, that the trick is to turn the lock screw down, so it then can't wiggle-jiggle a tiny bit when it gets moved and turn itself on in the case. I'm always skeptical of the readings, and checked it measuring a few things against a micrometer, it was right an the money, right down to the half a thousandth. I hate to say it, but I probably use it more as an inch to MM converter. Then measuring in MM's. Which I should really get some more metric reading tools, just seems like I still use standard for the vast majority of my work. Guess I'm just too old. Lol
As far as the South Bends go, that was the first lathe I used and was trained on in High School. So, it's just what I'm used to I guess. Really though, they will give several lifetimes of service with reasonable care with the infinite adjustability they were designed with.

 

[Stump Shot]

Now, finally we come back around to the gap between the piston bosses and what Alex, and I came up with for a solution to that problem, if it even is one. After several discussions with end user's and insiders of the Wiseco pistons, it all came down to two choices, one some work saw builds were just left as is and it is just okay to do so, and two, some racer dudes were purchasing stainless steel spacers from industrial Supply houses(sorry Home Depot fans) and using them to space out the connecting rod. Me being me, decided I would study on this further before acting. After the pea rolled around a few times in my noggin, I seemed to recall years ago, taking apart an old American made saw, either a Poulan or Homelite can't really recall, whatever it was, it had brass spacers used in such a fashion and that seemed a plausible option to me to attempt to duplicate.
After mentioning this to Alex, he didn't like the idea, to him he was envisioning washers from HD bouncing around on the piston pin. Which was not to be the case at all. I had even ordered the brass rod to machine the spacers from and had it coming already. So, with that squashed I had to come up with a new plan of attack. Pea rolled around a few more times and it came up with plastic, yes plastic, not just any plastic could I get my mits on some high heat plastic? Knowing that plastic can survive inside an engine with bearings having the cages made of plastic, the pea seemed like it might be on to something. Upon doing some research into the idea, I came across a product called PEEK, which stands for Polyester ester keytone. It has an extremely high melting temperature, has some lubricating properties to it and is machinable. It is already being used in industry for such things as pistons and rings in electronically controlled air valves and things of that nature.
This idea was then passed on to Alex, and I got the green light to goat a head. After some measuring a size of rod was decided upon- which was 3/4 of an inch across. Now I had a lightweight alternative to using stainless and control over keeping the bearing in and the connecting rod centered on the crankshaft.
Surprisingly I was able to come up with a drill diameter that when used left a snug fit on the wrist pin, then used a dial indicator against the carriage of the lathe to get an accurate thickness cut. Which I came up with to leave some room for movement and oil to come in just like normal.
For myself this was the most exciting part of the entire build, being something truly unique and made by my own two hands, that I now give to the world to try for themselves, so they choose to do so.

 

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[redline4]

I'm appalled that nobody suggested the use of JB Weld to make these spacers.

 

[hacskaroly]

Oh, to have the right tools for the job!!!

 

[singinwoodwackr]

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home depot or ACE would have been quicker

 

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home depot or ACE would have been quicker

True, but the delayed gratification...

 

[Stump Shot]

I'm appalled that nobody suggested the use of JB Weld to make these spacers.

Strangely enough, being the porters fix-all of choice, never crossed my mind when the pea rolled round. Would have been easy to make up a form to mold them in.

 

[singinwoodwackr]

Strangely enough, being the porters fix-all of choice, never crossed my mind when the pea rolled round. Would have been easy to make up a form to mold them in.

and...don't you have a 3-D printer?