2 cycle engine for saw build?

[vtdiy]

Hello all,new to this forum.

I built my house 8 years ago from lumber cut from logs left behind on the property I bought by a logging company.

I rented a Lucas mill to cut most of the dimensional lumber (floor joists, etc).

Before that I had been using an alaskan mill to cut the 28' 8x8 sills and summer beam and most of the 6x6 posts.

After the Lucas mill I built a band saw mill, which I've been using for about 6 years. Built a log arch, too

I kind of miss the Lucas for doing 2 by stuff.

I've read several of the swing blade construction threads here, and I've been tempted do build another saw  either swing blade or two blade.

I used to fly ultralight planes, and I have three 2 cycle motors in storage -- a Kawasaki 340 LC liquid cooled (brand new, never used -- surplus from John Deer Liquifire snowmobile manufacture, I think), (oil injected) and two used, but good Cuyuna UL II-02's. All are around 35 hp, I believe.

I was just wondering if they might be able to be used in that kind of project. I know the reduction needs would be a lot compared to a 4 cycle, gas consumption higher, etc. but I do have these on hand, while I don't have a 35 HP 4 cycle. They are also light compact units. The Kawasaki is a beautiful piece of work. It's been just sitting in a box for 14 years.

I kinda hate manual debarking on the bandsaw unless it's a big log, turning, edging for dimensional stuff, you probably all know what I mean. It's fine for slabbing and furniture stuff. I have room for two saws, or possibly could even re-use the track with a different head. I have lots of hemlock and white pine on my property The pine is 20-36 inch butt cabbage stuff, the hemlock is 8 to 18 inch mostly and there's a lot of it. Half the time when clearing space I just cut it and leave it because the bandsaw is a pain. I'd like to use it more.

What do you think?

Anyway, those engines have been sitting in boxes in my barn.

[Ianab]

Welcome to the Forum, as you may have noticed, very few things are totally impossible, especially around here. ;)

Personally, my swingblade mill has a 2 stroke engine, actually a big Stihl chainsaw, so it must be possible.

The gearing would have be right, but that's just an issue of some different sized pulleys in the system, and keeping the RPMs steady. I'm guessing the engines probably don't have any form of governor and just rely on throttle settings? Keeping steady revs is important, so you probably need to work on that. On my mill the big Stihl has a mechanical governor system running off an air vane by the flywheel (fan). When the engine hits full revs, the vane blow aside and pulls the choke on, and the engine blubbers a bit and doesn't rev any higher. So when milling you just hit full throttle and start cutting once the saw is up to speed.

Ian

[vtdiy]

Thanks lanab, good point about the governor. Definitely no they don't have governors, though as you say, nothing is impossible, and the vane type is used on air cooled 4 cycles. I'm encouraged to hear you have a 2 cycle mill, though.

I also just realized they don't have fans either, but again that could be done. The liquid cooled Kaw does have some dirt bike radiators, the Cuyuna's were cooled by airflow when flying, so they would need shrouds and a fan. The Kawasaki was the one I was leaning towards.

These are inline twins by the way. I think the Kawasaki weighs 35 pounds dry.

The cuyunas are also light, and being air cooled, it might even be possible to rotate the engines with the drive in a swing blade setup.

Just remembered, I have a 2.6 to 1 reduction gear that fits these engines. Cog belt. Bolts to the front of the engine.

[vtdiy]

This is one of the motors I was thinking about for a new swing blade mill, -- the Kawasaki 340 LC with the reduction gear in place.



My home made bandsaw mill:

[Ianab]

The cuyunas are also light, and being air cooled, it might even be possible to rotate the engines with the drive in a swing blade setup.

That's how my chainsaw swingblade works. No gearbox, just a belt drive with the correct pulleys to gear things down and the saw swivels with the blade. Being a chainsaw it doesn't care if it's upright or laying on it's side.

Ian

[Captain]

Welcome to the forum VTDIY.  Glad to have another swamp yankee aboard.  (That's a compliment everybody)

Captain

[Hilltop366]

The cuyunas are also light, and being air cooled, it might even be possible to rotate the engines with the drive in a swing blade setup.

That's how my chainsaw swingblade works. No gearbox, just a belt drive with the correct pulleys to gear things down and the saw swivels with the blade. Being a chainsaw it doesn't care if it's upright or laying on it's side.

Ian

That's what I was thinking.
Do those ultra lights use a float bowl carb or do they have a large diaphragm carb?

[buildthisfixthat]

hello welcome to the forum ,i think the most effeicent way to build the swing mill you have in mind would be to buy a large gas powered concrete or general demo saw 2 stroke or 4 stroke mount it on rails put the blade on and go ..the engines you have would be a nightmare to set up and cut logs into lumber then just to mention a few pontental problems  1)gear reduction blade arbor bearings,shafts,powerband very diffulct to zero in ,running to hot seized to cold fouled plugs ,custom exhaust ,cooling system yes it could be done but you will spend more time and money trying to use youre  2 stroke just food for thought also awsome bandsaw very nice build

[Dangerous_Dan]

Before I went electric on my mill I considered using a Rotax 2 stroke snowmobile engine. My thinking was use a diaphram type carb and swing the entire engine just like I did with the electric motor. I decided that electric was simpler and less maintenace. I still have the Rotax engine sitting on the shelf.

Adding a governer to control the throttle for a constant RPM was part of my plan.

DD

[r.man]

Vtdiy, that's a nice looking bandsaw, do you have any more pictures? Why do you find using the bandsaw to be a pain? There is a lot to be said for a motor that you don't have to buy and they are certainly powerful enough. If it were me I would use one of the two strokes if I didn't have to do much modification to switch to a four stroke. We know from experience that a four will work but we don't know that a two won't. If all you are risking is a bit of time it seems like a good risk to me. I would be more cautious if you had to buy a two stroke but they are just sitting there waiting to be tried. Good luck with it.

[vtdiy]

Hey Ianab, again very encouraging to hear.

Hey Captain, swamp yankee, heh, guess I'm a halfer -- mom is from New Orleans. I see Norton in your avatar. I used to work in Norwood before I moved here to build my house on 67 acres of "unbuildable" mess (badly logged, difficult perc. mostly 15 degree plus grade, stream crossing w/no bridge) but it turned out rather well with the help of a 1951 John Deere Model M, and the bandsaw mill. I was a tree climber in the '70s so the snags and windfalls didn't scare me off. Found a natural spring and built the whole house including foundation by hand cutting up mostly trashed white pine butts. Still can't get trucks up here most of the year for lack of a bridge. But it is beautiful and gets better every year.

@Hilltop, nice mills man! You are really resourceful with what is available, which is a high art, and I definitely pay attention to the details of your work here. To answer your question, diaphragm carbs. Mikunis.

@Buildthisfixthat. Well buying a concrete saw would kinda defeat the purpose of using what I have, if possible. And the fun of learning by building something new. But I appreciate the raising of possible problem areas. I'm not afraid of alignment. I cast and built a metal lathe in 2003,and a milling attachment, as well as a model disk turbine. I hand scraped the lathe ways.

I do have a new cuyuna (brand) exhaust and it's pretty tame for a two cycle, really pretty much just a silencer, not a tuned pipe. They were very conservative in design with an aviation engine. I also have all the UL gages including CHT and EGT, and tach to fit so I could check my temps at first, even if I didn't leave the gages on permanently.

@r. man thanks for the encouragement. I'm starting to lean toward the air cooled Cuyunas now because of the possibility of swinging the engine. I'm also wondering if I could rework the band saw carriage for this and make the two rigs interchangeable. Or I could just build a second carriage and use the existing track.

re. not liking the band saw: I mean that mainly for 2 by constuction grade stuff. I really hate manual debarking and turning the cant for the edging etc. With my brief time on the Lucas, it was really nice to just set up the log and strip it all the way down to the bottom. Don't get me wrong, I do like my bandsaw for slabbing cherry, etc.

I have thought about adding a small carbide saw to debarg in line with the blade, and maybe you guys have other ideas to make bandsawing 2by stuff faster. and easier I'm open to that.

@Dangerous Dan, your swing mill is an inspiration. I've really pored over those pictures. Funny you mention Rotax -- my first ultralight was powered with  Rotax 277 of 28 hp. I used to fly arounfd Punta Gorda, FL. I don't imagine you'll be re-powering your excellent electric with  the Rotax. But wouldn't be surprised to see some other project emerge from your workshop for it.

Thank you guys for the welcome.

[Slingshot]

Another welcome; and for my use a sawmill would be a better place for a Cuyuna than
an Ultralight. My first UL was a Quicksilver with a Cuyuna and the only forced landing I
had was when a sparkplug wire dropped off (inverted engine) and I had to set 'er down
in a cow pasture. Found the wire had dropped off, because they weren't safe-tied, so I
snapped it back on and had room for a take off so was on my way again. Lot's of fun
in those birds.     I have a Challenger I now with a 447 Rotax. Built
it myself from a kit.
The Cuyuna always ran with a too high exhaust temperature but didn't hurt it.



_________________________--
Charles -     

[sgschwend]

Since you have a frame make a swing sawhead for it.  I purchased mine from Brand X.

I was wondering what rpm you would be running and do you have a governor to hold to a tight rpm range?
Most swing mills are setup for the saw rpm to be about 3000 rpm.  The saw is manufactured to spin in the same plane at that rpm.

You band sawmill frame may need to be a bit wider, but perhaps you would work around that.

keep us informed on how it goes.

[vtdiy]

Thanks sgschwend. I would have to come upwith a governor. From other posts by builders like Firebass, I believe that the blade RPM is more like 2000 on a 20-1/2" diameter (about 8" cut").

[Ianab]

The RPM of the engine vs the blade aren't an issue. You will end up with a drive belt between the engine and the saw shaft anyway, so you just size the pulleys to suit. The 090 on my mill is governed to about 8,000 rpm, and that's just geared down to ~2,000 for the saw.

The power band of the 2 stroke isn't an issue either, you need to be operating at whatever revs the engine is happy at, if you drop down out of the power band that means you were pushing too hard, you aren't going to be cutting properly anyway and need to ease up and let the revs come up again. One advantage of the chainsaw is that you have a clutch built in, if you do load the saw up too much, you loose revs and power until the clutch slips and the blade actually stops. You just stop pushing, revs pick up again again, and you try not to do that again. So some sort of centrifugal clutch would be needed.

Governor and cooling would be the issue I can see, but they aren't show stoppers. One advantage with the saw is the engine isn't running full load all the time like it would in an airplane. You might run 20secs, then throttle off while you swing or adjust the carriage, then power on again.  Even if you leave the revs up, the engine is on the governor, not under power, so it's cooling off. For an air cooled I would consider an old school car radiator type fan mounted on the output pulley with some sort of shroud to direct air over the cylinders.

Ian

[vtdiy]

Ian, I think my mind is starting to show its age -- my only excuse is I haven't looked at the Cuyunas in 8 years, but now I think they do have fans, they weren't "free-air" as we used to call the fanless engines, at all. I believe I was thinking of the Kawasaki air cooled UL engines when I said they needed fans. I'm going to have to dig out the boxes and check. But if they have fans already, uhhh nevermind on that issue.

re. clutch -- I just replaced the whole clutch assembly on my Stihl last week, so I'm thinking about it now.

Also, I know what you mean about the 2 cycle power band. I believe these engines were at full hp at abut 6200 rpm (if that mind is still working at all).

I run my 4 cycle bandsaw engine at 2800 RPM, rather than the rated 3600. I have a tach on it.

[Ianab]

That's an advantage of most 4 strokes, when you drop the revs a bit you still have useful power and torque. A high performance 2 stroke has neither.

But you can gear the rig to run the engine at 6,000 and the blade at 2,000 easy enough.

My road car behaves more like a 2 stroke, max power is at 7,200 rpm, max torque at 6,000  : Get to use the gears a lot.

Ian

[Captain]

vtdiy - I should mention my avatar has Norton MA on it, but that is only true for the last 15 years of my life.  The first 26 were in Vermont.

Captain

[timbatrader]

Hi no experience myself but were thinking if you were going to use the tracks on the band mill you already  have would it be possible to put a hydraulic pump on your band mill motor and hydraulic motor on the swingsaw  not a cheap option but hydraulic motors on swingsaws are  simple to set up light and easy to use

[vtdiy]

Verified that the Cuyunas definitely are fan cooled, but also they are about 58 pounds and kind of bulky. I'm thinking it would be hard to swing any of the engines I have, especially with the exhaust on, and that a transmission would probably be required.

Starting to cool off on the idea a little. Ian's chainsaw motor makes more sense as a 2-stroke to me, with its built in clutch, small size, natural ability to be turned on its side, small exhaust, and light weight, etc. But I'm only considering a 2 stroke because I have these engines on hand -- not looking tyo buy a big chainsaw engine in addition.

It also seems to me that a homemade swing mill is going to be a stationary mill. Unless you have loads of suitable scrap aluminum, the cost would be pretty high to try to make something similar to a Lucas frame. Of course fixed was what I was thinking of at first -- especially if I was re-using the bandsaw track. But reading a lot more of the forum swing blade threads, I remembered what a great advantage it was to cart in the mill head and set up near the logs. Guess I'd really like a Lucas, but can't afford one.

I've been re-thinking my bandsaw mill and what I don't like about it. Basically manual debarking and turning to do edging. Also no saw sharpener or setter. Maybe I can work on those things in creative ways -- build some accessories/attachments that do some of this. Also get better at sawing, which this forum is going to be great for. I've been working in a self taught vacuum, and I'm sure I can improve what I do after some reading and gabbing here.

Captain, you had a Vermont education then.  I'm a little older than you -- I went to a one room schoolhouse in the late '50's in Bennington -- two grades in one room -- two blackboards at either end of the room and the grades faced in opposite directions. The teacher would tell the second graders to do homework while she taught the third, and not to listen in. Of course, we listened to what they were doing, which seemed much more interesting than what we were supposed to study! Kinda made kids eager to learn and move ahead, being told not to. Also you got a built-in review if you missed anything, next year.

timbatrader, hydraulics use a fair amount of the available power. However I once saw a small homemade split sternwheeler houseboat in Florida driven by tractor hydraulics, that was very cool.

[sgschwend]

Are you concerned about using a gearbox?  If not I would say you have a great idea about making a swingmill.  

Use your engines with a gearbox.  I would suggest you talk to Jay Brand about obtaining one of his gear boxes and arbors.  Then you would be able to use a Lucas 3000 rpm saw or a Brand X 2700 rpm saw. The four stroke engines are setup for a 3700 rpm, the Lucas mill has less gear box reduction hence the higher saw rpm).

Heck your engine will save you nearly $2,000.  The 25 hp Kohler Command weighs 94 pounds.

[vtdiy]

Thanks steve, I'll keep it in mind. I haven't abandoned the idea yet. But I will need to commit to a stationary mill, and a fair amount of complexity and money in the transmission. I need to think about it more.

Today I just put a deposit down on an old Ford 800 tractor with a backhoe and bucket in pretty rough cosmetic shape. Everything works, though. Some hose leaks, etc. But I can dig with it,and move logs. But that's definitely going to absorb some attention for the time being.

I'll keep thinking about the swing mill. Maybe electric, like Dangerous Dan's, would be better for me than  these 2 cycles seems like for the price of a transmission, I could get an electric motor, with a little searching, and have a simpler project. The current draw is the main hangup with that, and lack of 3 phase. Wonder if I could drive a 3 phase alternator with the 2 cycle engine?

[sgschwend]

John Davis the owner of Mighty Mite Sawmills tells me running an electric sawmill with and 3 phase generator is the worst of both worlds.  What he means is that you have taken on another big, complex machine to do what a gas motor can do.

To achieve a vertical cut you need a offset greater than the electric motor diameter so you will still need some pulleys and bearings.

Since the offset pulleys are needed you could go with a idler pulley for a clutch.

The electric motor would save on the transmission but it will not be free, you will need to have overload protection.  Circuit breakers will not likely be fast enough to protect the motor and contactor.  So really the transmission is a good proven idea.  I did see 2:1 reduction 40 hp rated one on Surpluscenter for under $200.  That would be just about perfect for a 6000 rpm motor (5760 rpm) you could easily use the pulley sizes to take care of what you wanted.

By using your bandmill frame and making a sawhead that uses a four post design you really have save another $2,000 in the cost for the frame, and associated dogs, and other parts a frame needs.

Heck you could likely setup a roundhouse so you could roll off one sawhead and roll on another. Now how cool is that?

[vtdiy]

Hello Steve, I looked for that <$200 transmission on SC's website but only saw 1:1 rt angle boxes.

[sgschwend]

Sorry it was a speed increaser.

I don't know if it can be reversed, seems like it wouldn't matter, just requires adapting to the shafts.  It was the second from the bottom a 1:1.92 unit.  But it is also only a 30 hp, I would think a 40-50 hp would be the size to get.