Why not a HEAT ALERT WARNING?

[PatrickIreland]

I don't think it would have to be expensive at all. A heat sensor, wire, and an LED basically. Still, since we ain't got it, there must be some impossible hurdle...maybe.

Shouldn't be too hard - a high-temp thermistor on the cylinder fins, watch battery and one of those ready-made flashing LEDs?
The onlyproblem would be calibrating it for each saw - you might have to burn out another piston to determine what is "too hot" for your saw!

 

[brages]

All we need is an oxygen sensor before the catalytic convertor, and one after the cat, and a fuel injection system... then we can use a computer control to make sure it's always running lean and clean (but not too lean) and the on-board diagnostics can make sure the catalyst is operating correctly.

Of course, you'll need an emissions check every year to make sure no tampering has occurred...


hmm... any job openings at the EPA...?

 

[max2cam]

Don't they all eventually burn up milling? some can just take it longer than others?

And it's over-heating that kills them. So whatever the cause of the heat (perfidious air leak, carb too lean, anti-American Chavez oil, human error, etc.), a warning light on the saw screaming "SHUT ME OFF!" would be a rather nice feature to have. At least some of us think so.

And like someone else mentioned, these new saws come lean from the factory and are prone to run heat, increasing the danger and need for a overheating LED warning light.

 

[max2cam]

the best thing you got are your sences to keep your saw safe.

You are certainly right, but my senses didn't tell me this was coming until it stuck in the cut. I had even let the saw sit and cool down before this happened. I wish an LED warning light had alerted my senses so I could have stopped and checked the saw over before the piston fried.

 

[max2cam]

Isnt there somekinda sticky thing you can put on and it change color at a certain temp range??? I cant recall what it was.....
I remember cutting in the summer time when it was hot with my dad and his Pro Mcc 55 would get hot and you could hear the gas boil....Now that was hot!!!!!!!

My bar got hot because the chain was dull, but I didn't think the saw was that hot. Still, I let it cool down, but not enough as it turned out.

A color change unit would be okay, but bright or blinking LED would be more noticeable. I'd take your system over nothing though.

 

[max2cam]

Sounds like a good idea. What about one of those "pop-up" things like they put in turkey to show when it's done? Just thread it into a boss on the exhaust side. It could be resettable.

I'd take your pop up system too if the bright LED light is not practicable. But it doesn't seem it would be as noticeable as bright or blinking light. After all, the operator is usually looking down at the saw when cutting.

 

[Rockfarmer]

All we need is an oxygen sensor before the catalytic convertor, and one after the cat, and a fuel injection system... then we can use a computer control to make sure it's always running lean and clean (but not too lean) and the on-board diagnostics can make sure the catalyst is operating correctly.

Of course, you'll need an emissions check every year to make sure no tampering has occurred...


hmm... any job openings at the EPA...?

Hey!!! :censored::censored::censored::censored:

 

[max2cam]

Get a tach and tune the saw correctly, and even a bit fatter than "correctly". Cheaper and more effective than any add on gauge would be.

Mark

Actually I'm thinking a stock factory heat warning light, not an add on.

Yes, that's good advice, and I now plan to get a tach for future use. But it would still be a great thing while cutting to know if something is going haywire and the demon of pernicious overheating is rearing its ugly head. This is a problem that all heat engines have (old Harley flatheads were notorious piston eaters and they were 4-strokes), and these high revving poorly lubed 2-stroke chainsaw engines could use a heat warning light, IMO. It sure couldn't hurt.

 

[Beetlekilled]

30 years ago when I raced Karts with 100cc Mac 91B1s, Yamahas etc the guy who built our motors got us into using tach/temp gauges mounted on the steering wheel. So you may be able to find one for milling if you contact some Kart shops. Don't remember where the sensor mounted (plug?) or what max temp was critical but we would run them lean for more power/RPMs. Good luck.

 

[max2cam]

Shouldn't be too hard - a high-temp thermistor on the cylinder fins, watch battery and one of those ready-made flashing LEDs?
The onlyproblem would be calibrating it for each saw - you might have to burn out another piston to determine what is "too hot" for your saw!

That's why I'm talking about a factory stock system calibrated for a particular saw and not an add-on item. Maybe it could be a special order item as some guys may not want or need it.

I would ideally want the sensor in the piston, but that being hard to do, I'd think in the cylinder wall near the exhaust port where the highest temps occur would be the next most logical place. But I'm no engineer.

 

[PatrickIreland]

All we need is an oxygen sensor before the catalytic convertor, and one after the cat, and a fuel injection system... then we can use a computer control to make sure it's always running lean and clean (but not too lean) and the on-board diagnostics can make sure the catalyst is operating correctly.

Of course, you'll need an emissions check every year to make sure no tampering has occurred...


hmm... any job openings at the EPA...?

It'll have to be CAN-BUS compatible as well, OBD II, etc. Program your saw with your laptop...

 

[max2cam]

30 years ago when I raced Karts with 100cc Mac 91B1s, Yamahas etc the guy who built our motors got us into using tach/temp gauges mounted on the steering wheel. So you may be able to find one for milling if you contact some Kart shops. Don't remember where the sensor mounted (plug?) or what max temp was critical but we would run them lean for more power/RPMs. Good luck.

I remember years ago guys fitting head temp gauges to their motorcycles. And cars have coolant temp gauges and low oil warning lights or gauges plus ampmeters or idiotic lights.

But we in the high revving, toy motor, poorly lubricated 2-stroke chainsaw world are forced to fly by guess-um and by-gosh while deep in the broad cut wallowing down an 8 foot log.

 

[PatrickIreland]

That's why I'm talking about a factory stock system calibrated for a particular saw and not an add-on item. Maybe it could be a special order item as some guys may not want or need it.

I would ideally want the sensor in the piston, but that being hard to do, I'd think in the cylinder wall near the exhaust port where the highest temps occur would be the next most logical place. But I'm no engineer.

I am.
That would be difficult to accomplish and add a fair bit of money to the purchase price of your saw because only 1 in 100 people are going to want it... A thermal switch or thermistor/LED combination would be easy to DIY if mounted on the fins and would cost a few dollars to do. It would take a bit of calibration but an adjustable inline resistor would take care of that - just run your saw until it is HOT (as you said your bar was), then tweak the resistor until the LED flashes at you.

 

[thomas72]

I know of two ways of measuring heat generated by an air cooled engine. One is exhaust gas temp other is head temp. I do not quite know the #'s but I think exhaust is up to 1,200 degrees and head them is around 200 degrees. I am not certain but for accurate head temp reading I would want the temp measured directly off the head of the cylinder not a cooling fin. This is really not needed in my opinion though. If you are that concerned then just check your spark plug after every cool down period. When I look for lean characteristics on my dirt bike I go to the sparkplug and golden brown in my opinion is optimum for power and reliability. If a spark plug starts turning a little white the carb gets fattened up a little or fuel delivery gets checked.

 

[PatrickIreland]

I know of two ways of measuring heat generated by an air cooled engine. One is exhaust gas temp other is head temp. I do not quite know the #'s but I think exhaust is up to 1,200 degrees and head them is around 200 degrees. I am not certain but for accurate head temp reading I would want the temp measured directly off the head of the cylinder not a cooling fin. This is really not needed in my opinion though.

It would be a nice gimmick though - milling away, suddenly your chainsaw tells you it is too hot by shining an array of ultrabright LEDs in your eyes blinding you for ten minutes (or forever) so you have to let go of the throttle...:greenchainsaw:

 

[PatrickIreland]

It would be a nice gimmick though - milling away, suddenly your chainsaw tells you it is too hot by shining an array of ultrabright LEDs in your eyes blinding you for ten minutes (or forever) so you have to let go of the throttle...:greenchainsaw:

Or, if you happen so be a blind chainsaw nut - it could be wired to a detonator with a small explosive charge placed nearby, maybe some ball bearings mixed in - so when the saw gets too hot, you get exploded!

 

[Taxmantoo]

30 years ago when I raced Karts with 100cc Mac 91B1s, Yamahas etc the guy who built our motors got us into using tach/temp gauges mounted on the steering wheel.

Back in the day when snowmobiles were air cooled and two stroke Kawasaki superbikes ruled the streets, plug washer pyrometers were quite common.
I even saw an abandoned H-1 Kaw at a university police auction with three head temp gauges on the handlebar, with wires going to the spark plug washers.

It seems a little odd to put a 2 1/16" gauge on a chain saw and run 12v to it, but for a $1000 milling saw it might be worthwhile. Best source for used ones is the snowmobile parts listings on eBay. Might have to buy a new washer to fit the saw's plug. I don't know if it will run on a 9V battery or not.

 

[demographic]

I thought that way that some tuners sort out two stroke motorcycle engines and cart engines is to have a air fuel meter in the exhaust?

And others have EGTs like the Digitron EGT more details HERE
I'm not sure how well the AF meters last in two stroke applications (some of the sled lot use them anyway) but the EGTs are used more commonly as far as I know.
Seems a bit technical and spendy for a chainsaw mind but...

 

[PatrickIreland]

I've been talking to an aircraft electronics mate, and he thinks it should be doable up to around 300 degrees c cooling fin temperature... for a few bucks, no more. Powered by a watch battery, thermistor on the fin or head or wherever, and an LED.
Anyone ever checked the temps of their saw with a pyrometer?
It could be an interesting experiment at least.

 

[keith66]

Do you think the big chainsaw companys don't do it because they would sell less saws per year and dealers would lose the money for labor costs of fitting a new p & c on a burnt up saw?