Finished My Mill

[BobL]

Bob is right, this is the biggest problem no using a traditional chainsaw. But, then it would be just another chainsaw mill. I have to have fun figuring this stuff out to make this engine work.

Bob,

If I were to use an old style Oregon roller tip that is exposed and not within the bar. I could attach a gear or shaft to it that I could turn a small pump to oil the bar just as a traditional saw would oil, right? ?????

jerry-

Sounds good, @ 7000 rpm, you will need some gear reduction, maybe cannibalize an old CS oil pump?

 

[BobL]

820wardsm, perhaps you already answered this earlier, but do you have any idea of your motor rpm's, either WOT or in the cut ? Just curious if your chain speed is anything out of the ordinary ?

Jerry and I had this conversation way back when he first started.

Unless Jerry's done something to beef up bearings etc max RPM for continuous heavy duty use is rated at 7000 rpm. Assuming he has maxed the performance at this RPM this is nominally ~9.5HP and 6.8 lbft. With this much torque he's not going to lose too many rpms in a cut so lets stick to 7000 rpm.

At 7000 rpm, with a 9 pin 3/8 sprocket he's going to have 44.7 mph, with a 9 pin 404, 48.2 mph.

Compare that to an 880 on 3/8 chain doing 9500 in a cut thats 61 mph.
That's a difference of 36% less.

The only way to go from here is increasing the cutting angle on cutters (or lower the rakers).

With that much torque up his sleeve he can look at a cutting angle of 10º which equivalent to a raker depth of 0.045" on new chain and progressively more thereafter which is what Will Malloff suggests for an 090. Theoretically this will create chips that are 80% bigger than 0.025" rakers but this will also reduce RPM in the cut - to what? I have no idea.

In theory that will make Jerry's mean machine about 44% faster than an 880 but I doubt that will be the case. My guess is it will be closer to the proportional difference in cc ie 134/121 = 11%?

 

[whitworthsocket]

Superb Engineering

Jerry,
You have done a fine job. Very neatly engineered.
My only comment for improvement is that.
I would like to see you put some finger protection over the nosebar guard.
Maybe polycarbonate or aluminium sheet.
Keep up the good work.
I am keen to learn how well it cuts.

Regards
Whitworthsocket

 

[mtngun]

Jerry and I had this conversation way back when he first started.

Unless Jerry's done something to beef up bearings etc max RPM for continuous heavy duty use is rated at 7000 rpm. Assuming he has maxed the performance at this RPM this is nominally ~9.5HP and 6.8 lbft. With this much torque he's not going to lose too many rpms in a cut so lets stick to 7000 rpm.

At 7000 rpm, with a 9 pin 3/8 sprocket he's going to have 44.7 mph, with a 9 pin 404, 48.2 mph.

Compare that to an 880 on 3/8 chain doing 9500 in a cut thats 61 mph.
That's a difference of 36% less.

The only way to go from here is increasing the cutting angle on cutters (or lower the rakers).

Thanks for clearing that up, Bob. Torque sounds great in theory but in practice chain speed in the cut wins the race, hence the trend toward higher revving saws.

What I was getting at is there doesn't seem to be any unusual lubrication requirements.

But, it is still an interesting and well executed design. It's thought provoking to see someone create a new CSM design instead of following the crowd.

 

[Kicker_92]

Assuming he has maxed the performance at this RPM this is nominally ~9.5HP and 6.8 lbft. With this much torque he's not going to lose too many rpms in a cut so lets stick to 7000 rpm.

Do you know what the torque curve for the 880 engine looks like for comparison? I'm curious how quickly it drops off as the rpms fall.

 

[820wards]

Jerry and I had this conversation way back when he first started.

Unless Jerry's done something to beef up bearings etc max RPM for continuous heavy duty use is rated at 7000 rpm. Assuming he has maxed the performance at this RPM this is nominally ~9.5HP and 6.8 lbft. With this much torque he's not going to lose too many rpms in a cut so lets stick to 7000 rpm.

At 7000 rpm, with a 9 pin 3/8 sprocket he's going to have 44.7 mph, with a 9 pin 404, 48.2 mph.

Compare that to an 880 on 3/8 chain doing 9500 in a cut thats 61 mph.
That's a difference of 36% less.

The only way to go from here is increasing the cutting angle on cutters (or lower the rakers).

With that much torque up his sleeve he can look at a cutting angle of 10º which equivalent to a raker depth of 0.045" on new chain and progressively more thereafter which is what Will Malloff suggests for an 090. Theoretically this will create chips that are 80% bigger than 0.025" rakers but this will also reduce RPM in the cut - to what? I have no idea.

In theory that will make Jerry's mean machine about 44% faster than an 880 but I doubt that will be the case. My guess is it will be closer to the proportional difference in cc ie 134/121 = 11%?

Bob,

Thanks for this information. I was wondering if I could lower the rakers because the motor does create more torque.

I have no way of testing the RPM on the motor at this time. With the larger carb/intake I should get more RPM from the motor.

thanks
jerry-

 

[BobL]

I have no way of testing the RPM on the motor at this time. With the larger carb/intake I should get more RPM from the motor.

Sure I understand that, and the power curves show the RPM going to 8000 and I'm sure it can do more. But these curves also show 5 pieces of useful information.

1) Recommended continuous RPM range 5000 - 7000 rpm - and for the rest of the discussion I'll stick to this range
2) The Maximum HP: 7 HP @ 5000 rpm and 9.5 at 7000 rpm
3) Recommended Maximum COntinuous Operating HP 6.2 to 6.5 HP
4) The Maximum Torque: 7.5 lbft @ 5000 rpm and 6.8 lbft at 7000 rpm
5) Recommended Maximum Continuous Operating Torque 7.5 to 4.5 lbft

The way I interpret those figures is that while it is possible to extract 9.5 HP and 6.8 lbft out of the 820, the maximum continuous operation HP/Torque that should be extracted from the engine are the lesser set. I guess one set of data are for some sort of racing config and the other is for endurance tasks

I assume they give these two ranges because the lesser set are all the, crank, con rod, piston, cylinder, rings etc can take on a continuous long term basis. So even though your carby and intake are larger and the engine is capable of more RPM and more HP/Torque, one could still ask is the rest of the engine up to the task?

For all I know the 820 specs may be conservative and the engine may well be strong enough to take the sort of punishment that is involved in milling. Pro CS manufacturers are well aware as to what their users do with their products. One of the reasons the 090 is around 50% heavier than the 820 is because everything on the 090 is beefed up to take the continuous battering that happens during continuous high load WOT operation. The pistons and cylinders on pro CS power heads are rated for a minimum 2000 hours of continuous WOT full load - thats 8 hours a day for 5 days a week for 50 weeks. It doesn't sound like much but there are not many other small engines that can operate for this long under these conditions.

 

[sachsmo]

beauty

Wood surfer,

The 820 PowerBee motors have been used on a number of chain saws. I have a Montgomery 820 that used the same motor as I have used on the mill. The motor on the mill has been updated to a 1" intake manifold and carb. The Wards saw I have has the same carburetor in a 90 degree intake, electronic ignition and carbon fiber reed valves. I'm running a 30" Cannon bar and it cuts dry Oak like butter. My saw probably operates in the 7,000-8,500 RPM range, but it has plenty of torque.

There a a number of competition saw build on the WARDS frame. My friend Art Martin built a saw with this motor w/duel carburetors.

Here are a few pictures of the saw with the 820 PowerBee Motor.

I love that saw!








It reminds me of the old Johnson 35 Golden Javelin my dad had when we were kids.

It was behind an 15 ft. Lyman lapstrake speedboat.



That old 2 stroker had a really mean idle, and would scream at wide open throttle.


It threw some needle bearings, Dad bored it out and put some big slugs in it.



My Dad was a Master Mechanic.

 

[820wards]

Jerry and I had this conversation way back when he first started.

Unless Jerry's done something to beef up bearings etc max RPM for continuous heavy duty use is rated at 7000 rpm. Assuming he has maxed the performance at this RPM this is nominally ~9.5HP and 6.8 lbft. With this much torque he's not going to lose too many rpms in a cut so lets stick to 7000 rpm.

At 7000 rpm, with a 9 pin 3/8 sprocket he's going to have 44.7 mph, with a 9 pin 404, 48.2 mph.

Compare that to an 880 on 3/8 chain doing 9500 in a cut thats 61 mph.
That's a difference of 36% less.

The only way to go from here is increasing the cutting angle on cutters (or lower the rakers).

With that much torque up his sleeve he can look at a cutting angle of 10º which equivalent to a raker depth of 0.045" on new chain and progressively more thereafter which is what Will Malloff suggests for an 090. Theoretically this will create chips that are 80% bigger than 0.025" rakers but this will also reduce RPM in the cut - to what? I have no idea.

In theory that will make Jerry's mean machine about 44% faster than an 880 but I doubt that will be the case. My guess is it will be closer to the proportional difference in cc ie 134/121 = 11%?

Bob,

I hope folks are not thinking that I'm trying to compare or compete with an 880 or 090 saw. I am using this motor because of it's simplicity it's power and the fact that I purchased it new for a very reasonable price. I'm also using it because I didn't want to spend $2K on a saw that is not going to see extended weeks of milling like a larger saw might do. This may also be a way for people to look at other options for motors to mill wood. I will do some milling and report back to the thread what I found that worked and didn't.

jerry-

 

[BobL]

Bob,

I hope folks are not thinking that I'm trying to compare or compete with an 880 or 090 saw. I am using this motor because of it's simplicity it's power and the fact that I purchased it new for a very reasonable price. I'm also using it because I didn't want to spend $2K on a saw that is not going to see extended weeks of milling like a larger saw might do. This may also be a way for people to look at other options for motors to mill wood. I will do some milling and report back to the thread what I found that worked and didn't.

jerry-

Jerry, Sorry if it sounded like I setting up some sort of a competition. What I was trying to do was to give the other members some sort of spec comparison of cc-hp-torque etc with a CS they might be familiar with.

I'm right behind you on trying out this "gutsy" lightweight motor and as you say ". . . a way for people to look at other options for motors to mill wood" , and your workmanship and attention is a great example to us all. Like you say - if it handles periodic mill just fine it could a cheaper way for folks to access powerful milling engines - and even if it runs for only half the time of a regular CS before needing an overhaul that's still an awful lot of milled lumber to deal with!

 

[whitworthsocket]

Jerry,
We are all waiting as Im sure you are too to go and try out your amazing saw.
It takes a special type of person to think outside the square and thats what you have done.
I wish you every success.
Regards Whitworthsocket

 

[sachsmo]

Bob,

I hope folks are not thinking that I'm trying to compare or compete with an 880 or 090 saw. I am using this motor because of it's simplicity it's power and the fact that I purchased it new for a very reasonable price. I'm also using it because I didn't want to spend $2K on a saw that is not going to see extended weeks of milling like a larger saw might do. This may also be a way for people to look at other options for motors to mill wood. I will do some milling and report back to the thread what I found that worked and didn't.

jerry-

Super engineering on that mill, the one I built took considerably less thought.

If that Wards 820 ever needs a new home, you can PM me anytime!

I've never seen another, and yours is a creampuff. Nice, nice old saw!

Like I said earlier, looking at that beauty brought back some very fond memories. Thanks, and Happy New Year! Mo

 

[820wards]

I Milled Wed-Thur Finally....

Bob,

Finally got to mill yesterday and today. I'm addicted.....

The mill worked flawless. The clutch I built works perfect, I think anyone needing a clutch for an odd application, this works!

Only problem was two screws that hold the handle vibrated loose. When I assembled the mill after painting I forgot to locltite them. I think I will also back them up with a nylock nut.

Here are some pictures of what we milled. It is a Ash tree from my friends front yard he had to take down last year.

Tree Ready for Milling

First Cut

Three slabs from this log

Bob, me after we milled, back was OK after two days of milling. The handle bar worked really good. Leverage was good and easy to guide the saw through the log.

I clipped an image from one of the other pieces we milled.

I did put together a temporary drip feed nose oil bottle from a gear lube bottle. I'll be making another aluminum bottle to replace it as soon as I machine the fitting bungs. I only used the manual oil pump for the sprocket end of the mill and it put out plenty of oil.

Now, I have a video of the saw in operation I would like to post. Can anyone tell me how I can do that? The saw sounds nasty, and had way more power than I expected. It cut through the logs with ease.

Guys, I've had enjoyment building this saw and I know I will enjoy using it this coming New Year.

Happy New Year to everyone!

jerry-

 

[820wards]

Jerry,
We are all waiting as Im sure you are too to go and try out your amazing saw.
It takes a special type of person to think outside the square and thats what you have done.
I wish you every success.
Regards Whitworthsocket

Thanks, my friend Brandt and my son Chris used it today and we had great fun milling. My mill does not have measuring increments on it so we sawed blocks the thickness we wanted the slabs and marked them accordingly for future use. Sure saved time setting the slab thickness.

We even cut one log that we sliced a piece off that was only 1/4" thick. Veneer? The mill cut very true/flat and on every cut. I was very please to look down the slabs to see a very flat surface.

jerry-

 

[820wards]

Super engineering on that mill, the one I built took considerably less thought.

Like I said earlier, looking at that beauty brought back some very fond memories. Thanks, and Happy New Year! Mo

Thanks.

If that Wards 820 ever needs a new home, you can PM me anytime!

** I've had a lot of offers for the saw. It was the first saw my Dad bought and at 15yrs. old it was the first saw I ever used. What a way to learn.

I've never seen another, and yours is a creampuff. Nice, nice old saw!

Here is a picture of one that Art Martin built from a frame I found getting ready to go to a local aluminum recycle place. The frame was broken right at the trigger pivot and I was able to tig weld it back together. I then drilled and tapped the pivot for 5/16" and thread and JB Welded a 5/16" aluminum rod I made. I then re-drilled the trigger pivot hole. No slop in that trigger. Art built a race saw from that frame and did a gorgeous job.

Here are some pictures of the finished saw running duel carbs, shaved fan blades and cool paint scheme.

Glad you like seeing the old saw still in use.

jerry-

 

[820wards]

Here is some video of the mill in action. It's nasty loud!

There are also other detailed pictures of the mill in my photobucket.

jerry-

http://s450.photobucket.com/albums/qq222/820wards/?action=view&current=Production2em.flv

 

[sachsmo]

Thanks for the vid, and pics of the dual carbed 820 (082).

I can see, or should I say hear why they called that old screamer an Power Bee. Man that engine sounds like a torque Monster!
Props for the excellent engineering and choice of powerplant.

That engine is an old moPar engine is it not?

I think Mike Acres site lists the powerheads as coming from Chrysler marine division.

 

[olyman]

jerry, others have spoke of it in regular cs's. after they came thru the cut--it slowed down,and they shut it off--some have mentioned not to do that--let it idle for a bit--to cool it down--as milling really creats heat-the one time i milled the cottonwood with a old 090--i let it idle for about 1 min--

 

[flashy]

Here is some video of the mill in action. It's nasty loud!

Being in an enclosed area makes it seem louder.

 

[irishcountry]

Awesome job like the vid!! Keep up the good work and have fun with the end result of your hard work!! Happy New Year