Jack’s Husky Infused 440/460 Hybrid

[Duane(Pa)]

I don't know if this is true or not but I've heard some of the stihl vents are somewhat epa restricted.

Also, the foam type filling in fuel filters is necessary for eliminating the tiny air bubbles the vibration of a running saw creates. Milling or long cuts that way can burn a saw up.

Kind of like cavitation...Good to know!

 

[psuiewalsh]

been thinking about how to back pressure or flow test a fuel filter so as to eliminate that in diagnostics. ( me being a diagnostics guy and all... ).... kindda like an early nerve conduction ..

If you setup a constant displacement pump drawing through the filter you could put a pressure test port in the line and see hat the pressure difference is filter material vs non.

 

[blsnelling]

KISS

 

[psuiewalsh]

Nah. Frankenbuilds are great.

 

[mdavlee]

3120 filters are almost double in size to a 395 and down.

 

[Outback]

This is not aimed at Doc. Very cool build. Andy or whatever his name is should disclose the information below if he's selling titanium wrist pins. Not just say its for racing.

Titanium galls. It is not a bearings surface. CJ is correct, sleeve it in steel or plate it with something hard. Titanium is lighter and stronger than steel but not harder on the surface. It scratches just as easy as aluminum does, it's swarf will ignite with the smallest spark. It burns in pure nitrogen to give us those gold TiN coatings.

Don't put hardened rollers on soft sht. Think it over. Don't drink the cool aid.

 

[Chainsaw Jim]

Not sure why they put a hole in the bottom of the boss. The pin shouldn't be rotating in the bosses, so no need for lube.

It actually does move before it expands from heat.

 

[CJ Brown]

It actually does move before it expands from heat.

You can correct me if I'm wrong, but as far as I know, aluminum expands more than titanium as the temps go up. The titanium pin should actually become looser in the pin bosses as temps go up.

 

[Chainsaw Jim]

You can correct me if I'm wrong, but as far as I know, aluminum expands more than titanium as the temps go up. The titanium pin should actually become looser in the pin bosses as temps go up.

I'm not educated in the difference of expansion rates between aluminum and titanium. But if the titanium engineering leaves that much room for expansion I'll assume titanium at least doubles the expansion rate. Either way, I still see a need for lubrication until the expansion process captures the pin to lock it in place.

 

[Bilge Rat]

In my limited experience doesn't ti heat as well as cool very fast, faster than aluminum?
My lifelong fishing buddy, a Lockheed machinist, inspector that worked a lot on special parts and fix this problem now made many ti parts.
He said ti does not play well with other materials when set up to normal clearances. Based on the other materials you had to rethink your #s while looking at the heat on the part. It made a difference wheather it is a long heatsoak or short intermittant heat.

A hollow bolt/tube of ti heated would instantly get hot enough to burn fingers. By the time you said a few choice words you could pick it up off the bench and it would be room temp.
You could not even cuss it before it cooled down..

Doc keep going , we need more thinkers/innovators. This is how redneck racers taught the auto industry how to build cars.
Saw a few cylinder heads sent to a porter buddy who did his work on one cylinder then sent it back to an address that was owned by GM..

 

[CJ Brown]

Here is a link to a table that lists the expansion rates for many types of metals. Perhaps someone will find it useful at some point down the road.
https://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html

 

[Bilge Rat]

Remember expansion and heat gain?loss are 2 different things going on at the same time.
Clearances may be changing based on expansion at different rates and heat transfer/ conduction . Then when both parts have normalized both parts may be at the intended clearance #s.
One metal may try to pull heat from the other then reverse the transfer making the clearance constantly change.

Sorry i cannot express this in a logical manner. Logic and sanity are not always present in my head!

 

[Stump Shot]

Nothing against this build thread or anything or anyone in it, I would like to share a conversation I had just the other day and you folks can decide for yourselves what if anything to take from it as I can make no claim to it. On a current build I was going over some options with the owner one of which happened to be the piston pin. Seeing as a quick revving saw was part of the goal, I mentioned having a smaller inner diameter pin that would reduce weight. This was quickly rejected and rebutted and the heaviest pin was asked to be put in the saw. I asked why, as this was contrary to the goal it seemed to me. The response was that the weight was not a concern as much as the pin needed to be a good heat sink to help keep the piston and bearing cool with the extra stresses and heat from turning the engine into a high performance one.
So I've been rolling this around in my pea brain when the discussion turned up here. Surely there is more to think about as in this case a larger piston than stock being used changes that whole dynamic, but will be something to consider for myself into the future as there are lots of things to contemplate when messing around trying to make a saw run betterer than it was designed to. Seeing that Stihl switched to a larger pin diameter only bolsters this thought. Even though I do like the idea of new parts technology coming along to help us along the way. As always the open discussion here at ope with everyone's input of knowledge will eventually win the day, having separated the wheat from the chaff, of what works. Which gives me the confidence to keep trying new things, as even if I fail, I'll have learned what not to do.

 

[MustangMike]

Henry Ford (may not be exact): Failure is the opportunity to start again, but with more knowledge.

 

[wcorey]

Titanium is only stronger than steel in regards to comparable weight, with a dimensionaly identical part steel will be stronger.
When it was first being used in various types of racing, people were exactly reproducing steel parts like con rods with ti and having tons of failures, not realizing the part needed to be larger to be as strong. This led to it being banned in many instances until people started to figure it out.

Ti does have odd heat sinking properties, I remember belt sanding a high spot off a small piece, like an inch.
Was cool holding it with my bare hand but when I touched the high spot, a puff of smoke came off my burned fingertip.

It's possible the extra clearance for expansion of the ti pin is more for the bearing clearance as opposed to the pin boss.
It is hard to imagine using ti as a bearing surface.

As to a heavier pin being a heat soak, once the pin is up to operating temp it doesn't seem like it would move/dissipate significantly more heat than one that's a bit lighter.
Stihl going to a larger pin diameter likely has more to do with increased bearing area and/or stronger rod end.

 

[RI Chevy]

Titanium is terrible at heat dissipation.

 

[Chainsaw Jim]

Nothing against this build thread or anything or anyone in it, I would like to share a conversation I had just the other day and you folks can decide for yourselves what if anything to take from it as I can make no claim to it. On a current build I was going over some options with the owner one of which happened to be the piston pin. Seeing as a quick revving saw was part of the goal, I mentioned having a smaller inner diameter pin that would reduce weight. This was quickly rejected and rebutted and the heaviest pin was asked to be put in the saw. I asked why, as this was contrary to the goal it seemed to me. The response was that the weight was not a concern as much as the pin needed to be a good heat sink to help keep the piston and bearing cool with the extra stresses and heat from turning the engine into a high performance one.
So I've been rolling this around in my pea brain when the discussion turned up here. Surely there is more to think about as in this case a larger piston than stock being used changes that whole dynamic, but will be something to consider for myself into the future as there are lots of things to contemplate when messing around trying to make a saw run betterer than it was designed to. Seeing that Stihl switched to a larger pin diameter only bolsters this thought. Even though I do like the idea of new parts technology coming along to help us along the way. As always the open discussion here at ope with everyone's input of knowledge will eventually win the day, having separated the wheat from the chaff, of what works. Which gives me the confidence to keep trying new things, as even if I fail, I'll have learned what not to do.

A thicker piece of steel retains heat longer than a thinner one, though a thinner piece will reach a higher temperature much faster. Unless the heat is extreme, the larger piece of metal will never reach as high a temperature as a smaller one can.
That whole idea checks out.

 

[drf256]

Akin to aluminum connecting rods. Aluminum weaker, but lighter. So the rods are beefier, and not recommended for street use because of longevity issues.

This pin is coming out of the saw in the next 48-72 hours. I'll post pics.

It's getting replaced with an OEM pin, turned down to size on the lathe.

 

[wcorey]

A thicker piece of steel retains heat longer than a thinner one, though a thinner piece will reach a higher temperature much faster. Unless the heat is extreme, the larger piece of metal will never reach as high a temperature as a smaller one can.
That whole idea checks out.

Yup. But if they only wanted a pin with more thermal mass, why redesign when they could just use a thicker walled pin...

 

[drf256]

Here’s 3 pins. Oem 046, oem 064 and meteor