M-14 - Engine vibration transferred to mill frame?

[Birk-man]

Hi all,

The last piece I need to complete the drive train from engine to saw blade is a coupling to connect the engine to the mill.  When my 50 HP Deutz diesel is running there is a significant amount of vibration. 

I am considering either:

1) Carefully aligning the output shaft from the speed reducer on the engine with the jack shaft on the mill frame and using a flexible coupling to connect the two shafts.  This would take advantage of the coupling that came with the engine and would tie right onto the 1/1/2" diameter jack shaft.

2) Finding a PTO driveshaft (like those used to connect implements to tractors) and shortening it so the engine can be close to the mill.  This option would require more monkeying around to find/fabricate the appropriate matching ends to the drive shaft and I'm not sure how well the driveshaft would remove the engine vibration.

Does engine vibration transferred through to the mill frame effect the sawblade and the straightness/smoothness of the cuts?

Thanks for your help and suggestions - as always!

Peter Wendel

[bandmiller2]

Pete,vibration will affect everything on the mill,not good for the saw has a tendency to cause it to chatter in the guides.What are you using now if you could possibly show us some pictures.Most folks use universal joints like in an auto or truck drive shaft or as you mentioned tractor pto shaft.If you have too much of an angle between the engine output shaft and the arbor you will get pulsing, and the U-joint crosses must be in phase.You should also have a weak link be it "V" belts, slip clutch, or shear bolt.Give us more information.Frank C.

[Birk-man]

Frank -

I added a couple of views of the Sketchup model of what I am considering for my Belsaw M-14 set up to my gallery. 





It would have three belts to provide some slippage. 

I could also put a shear bolt into the mechanism as part of the motor to jack shaft connection. 

I found a short drive line at the tractor salvage yard so I think I am going to cut it as short as possible. It's been suggested that I need at least a 1/4" of shaft-to-shaft miss-alignment for the universal joint to flex and keep grease distributed in the joints. 

I'm concerned that the engine vibration is going to transfer through the drive line to the saw frame and cause problems with the accuracy of my cuts.

I'm open to any and all suggestions!

Peter

[Birk-man]

Here's another try at including the images in my post - Peter

[Stan snider]

A Longer drive shaft will smoothe out vibrations somewhat.  The longer it is the more critical balance will be. I would much prefer a P.T.O. than belts if the speed reducer gets you in the right R.P.M. range.  Mine has a slipclutch on the end of the mandrel off of a Bush Hog brand mower.  Stan

[bandmiller2]

Peter, that lashup you have shown should work fine even a short driveshaft with the two "U" joints will eliminate the vibration your worried about."V" belts are a good thing on a mill as a weak link and to reduce pulsing and vibration.Sometimes when belts are cold they tend to take a set but after a short run they warm up and smooth out.Frank C.

[captain_crunch]

You need V belt drive between power and arbor or things fly appart

[sandhills]

captain crunch, just outta curiosity what flies apart?  Ours is direct drive to the mandrel but want to make some changes.  We're looking at about 80 hp and 540 rpms, any suggestions?

[captain_crunch]

Take a look in my pics of my drive set up. PTO to arbor is the way they built em back then I have a jack shaft from arbor to PTO drive shaft and this with added bearing on arbor

Here is a pic
Brian

[captain_crunch]

Hope this helps you. My carrage runs off Hyd motor rather than the factory belt system. These critters are not over built on arbor bearins part

[Birk-man]

Hello Capt Crunch,

It's not clear from your photo if the lower pulley is attached to the mill frame or if it is completely separate?

It looks to me that the upper bearings on your mandrel shaft are supported by a frame that is connected to the mill track.  And I assume that there is some structure that resists the tension of the belts on the two pulleys.  That leads me to think that there is some structure that holds the two pulley shafts apart.  Do I have that right?

I see the tail end of a drive line that connects to the lower jack shaft pulley.  Does that isolate engine vibration from the mill frame?

I did not include the belts in my Sketchup model but the drawings I put in my earlier posts show the two pulleys and the shafts attached to the mill frame.  Also not shown is the drive line that would go between the engine and the smaller pulley on the jack shaft. 

What are the critical differences you see between your set up and what I am proposing?  I appreciate your insight since I am flying by the seat of my pants on this without much first-hand experience in this arena.

Peter

[bandmiller2]

The classic belsaw setup is with a PTO shaft with shear bolt from a farm tractor to the mill arbor,it works.An improvement is what Cappy Crunch has done for a couple of reasons,less angularity between tractor pto and arbor,and the option to run the saw at higher than 540 rpm.The belts also seem to smooth out the power.A handy trick to relieve stress on arbor shafts that extend belond the bearings is to mount pillow block bearings on the shafts and connect them with an adjustment such as threaded rod in a pipe where you can take much of the strain off the shafts and keep your belts tight.

[paul case]

the belsaw in the pic looks exectly like the one i had except my pto shaft was directly on  the arbor . factory made that way and with 5/15 shear pin set up. i dont recall any engine vibration or other problems with this set up except some models of tractors pto didnt turn fast enough to work right. i dont remember what speed the blade was stamped but my m farmall was horse enough to pull it but it didnt turn fast enough. the 930 case however turned a lil faster and never  ever slowed down in the cut . slowing the blade was the worst trouble i had with this set up. i would imagine that is why the fellas that was set up to saw a lot went to a big diesel negine. pc

[metljakt]

One cure for engine vibrations at the point of contact is timeless..........install a flywheel. 

[sandhills]

Can anyone tell me what the optimum rpm for that saw is?  Ours is 540 pto but I would like to change the drive system and can re-gear it to what is right. thanks

[captain_crunch]

Pic don't show it well but we added a bearing to end of arbor shaft also pto drive has two bearings on belt pully. This was done because Mill sets 4 ft above tractor to make clean out below mill. Belts calm down vibration as well as add a slip factor but this mill has been altered by a feller that has run these mills for 50 years.

[bandmiller2]

Sandhills,theirs quite a range of rpm's your saw could be hammered for.As a general rule smaller saw can turn at higher rpm.High production modern mills use fast feeds and higher saw speed.More rpm's mean slightly more production but more saw maintenance mostly they need more tension.Belsaws of course are setup for 540 to match tractor pto rpm's that 40" blade could be tensioned to run at much higher speed like say 700/750,myself I wouldn't go that high.Unless your in a big hurry 600 rpm is a good speed and usally your saw hammered for 540 needs no retensioning to run at that speed.Best to ask your hammersmith.My own mill is a Chase the guy before me ran the 50" saw at 750 rpm with the diesel wide open,too fast for this old guy, dropped down to 600, engine at 1800 were boath happier now.I'am sure outhers here have an opinion on this matter,you won't turn a Belsaw into a high production mill but you can make minor improvements.Frank C.

[sandhills]

Thanks bandmiller2, not looking to turn it into a high production mill, just wonderin if anything needed changed.  We haven't set the mill up yet so now is the time to do any needed mods, I do like captain crunches drive set up and also would make it easy to run a hydraulic pump off of.  Ours has a 52" blade and with the tractor at an idle it seemed like it was really moving, don't care to speed anything up much! ;)

[bandmiller2]

Sandhills,what mill do you have I assumed it was a belsaw as thats what we were talking about.A 52" is a big saw 540 rpm would be a good speed to run at,if you can line it up with your tractor PTO try it.Frank C.

[captain_crunch]

My 42" don't like higher rpms I watch front of blade while cutting and adjust engine to get wabble out of it. I have a impovises throttle with cord to tractor which lets me idle tractor when rolling logs which cut my fuel usage by 40%

[sandhills]

bandmiller, to be honest I'm not sure what I have.  A couple of neighbors and I went together and bought the saw on an auction this spring more for hobby than anything else.  I was looking up sawmills on the internet a few weeks before the sale to see what we were getting into and found the FF.  The serial tag on the carriage is worn off to the point where I can't read it but after looking at the photos here I'm sure it's a belsaw.  I was thinking I read here before about a m-24 belsaw, can't tell for sure by the pics but I think ours is a little heavier than the 14's posted.  Have you ever seen one with hydraulics (log loader/turner) or are they built to light for that?  Right now it sits beside the shop so it would be easy to do all this before we get it set, however it is on wheels so we could pull it back over to make necessary changes.  Never put a tape to it but it took the full length of a semi flatbed to get it home including the log table.  I emailed fishpharmer pics of it maybe if I ask real nice I can get him to post them for me, I'm not real intelligent with the computer

[paul case]

the m14 i had was kinda light. the book said that if you have a log big enough that the first cut with the 40'' blade didnt cut all the way through that it should be taken off the mill to be turned. pc

[captain_crunch]

This is how we turn logs so weight is not on carrage when dealing with bigger logs


Never filp cant against set works unless you like repairing things ;D ;D Also in the one pic you can see the 1/2X1/2 steel added to cross bars on carrage. This not only beefs up the carrage but cants slide easier on narrower surface

[rpg52]

Not to hijack this thread too much, but - Captain Crunch, how do you turn down the throttle remotely? 

I assume you are on one side of the track while your power source (tractor) is on the opposite side?  Do you use a bowden wire (like is used on chokes, back when most engines had carbs)?  Or, do you use cable and pulleys? 

I'm debating since my power source is a Detroit Diesel 3-71, and the throttle consists of a knob, not a lever like a tractor.
Thanks,

Ray

[sandhills]

rpg52, would it be possible to run a cable, say off an old straight truck that would engage the pto or hydraulics under the mill to your detriot? Don't know if it would be long enough, and I'm assuming your throttle knob runs a cable as our 671s do.  Wouldn't be too hard to build a little bracket within reach of the sawyer to mount the push/pull knob on.  Alright dang it now you guys got me thinking again, better go measure some more. ;D