blade speed

[donny hochstetler]

I need to check R P M s on my blade speed,  they want 150.00 for a gauge, i'm to tight to buy it now, as i'm not working much these days, maybe i'll buy one next summer, I can borrow one from a freind. but have to drive 35 miles to get it,  35 to take back, equals almost 150.00 if you figure gas n time ect. my question is can I just play with this til I hit the sweet spot or is this very critical,   by the way this is a new to me used *1 meadows ,mjll   48 " blade, supposed to run 550 rpm,s previous owner said it cut fine, so I expect no problems,   thanks

[dgdrls]

Do you know what your engine/motor is turning at operating speed?

If so I would think you can compute your blade rpm based on your pulley/reductions to the main blade shaft,

DGDrls

[eastberkshirecustoms]

I have a cheapie tach similar to this one: http://www.ebay.com/itm/Digital-Laser-Photo-Tachometer-Non-Contact-DT-2234C-/330654150758?pt=BI_Generators&hash=item4cfc85f066
It works really well.

[sawsmith]

Electric or Diesel power? RPM of motor and pulley size on mandrel and power supply? with this info rpm can be figured out to tension the blade

[bandmiller2]

Donny,I have a Stewart Warner handheld tach you hold to the end of a shaft just like reading a speedometer only in RPM.Machinests used a simple counter,you used the second hand on your watch,hold it to the shaft for one minute.I'am sure their are electronic replacements. I wonder if you could put a chalk mark on the saw and count the revolutions in one minute time,worth a try. Frank C.

[Meadows Miller]

Gday

Congrats on getting yourself a Real Sawmill Donny  ;) ;D ;D ;D ;D 8) 8) 8) 8)

Did you buy it with a motor and drive line or just the mill on its own as if its complete it should be within the sweet spot for the saw just check with the owner what rpm he was running the power unit at mate ;)

Good luck and I wanna see some pics Mate ;) 8) 8) 8)

Regards Chris

[paul case]

Donny,I have a Stewart Warner handheld tach you hold to the end of a shaft just like reading a speedometer only in RPM.Machinests used a simple counter,you used the second hand on your watch,hold it to the shaft for one minute.I'am sure their are electronic replacements. I wonder if you could put a chalk mark on the saw and count the revolutions in one minute time,worth a try. Frank C.

If it is turning 550 rpm that would be almost 6 counts per second and you would get dizzy in less than 15 seconds.    PC

[donny hochstetler]

thanks guys for the feedback,  I"m gona get it going this weekend, hopefully, 8) 8) I got an old cummins power unit from my dad, that hasn"t been run in yrs. we got it going,  serviced it , it runs real nice, also I was wondering, I was told to run it at 550 rpm,s,  is that rim speed, or is that the speed of the shaft? I"ll try to get some pics. I got 4 boomtruck loads of logs for starters, some tie logs, the rest is blocking, I would like to haul my lowgrade home from my logging jobs, so I have work when its wet, or during winter, I can tell I"m getting old, I dont like to bore around in the mud like I used to, its so wet in ohio its pathetic, wont  hardly freeze ,even though we were able to sneak in on my job this week n get 6 loads out, th at have been setting there since the last of october it has thawed out again , good day ya all

[Ron Wenrich]

Shaft speed.

[steamsawyer]

Donny,
The rpm you are looking for is the saw shaft speed. It needs to turn 550 for the blade to stand up and run streight.

When you first get going watch the blade edge wobble at low speed then as you slowly bring it up to speed watch it flatten out an run streight and true. If the blade is hammered for 550 rpm you need to run as close to that speed as possible. Too fast will also cause the blade to flutter.

Do some calculations for a good pulley ratio that will get your engine into the best rpm for its horse power curve. If your blade is hammered for 550 it needs to turn 550 in the cut. You might need to set the no load speed a little higher to allow for the loss in speed when the governor picks up for the load. A mechanical governor will never bring its engine back up to the original speed before the load was applied.

First let me say, I am by no means an ex-squirt on circular sawmills so your mileage may vary.

Google... Circular Sawmills and their Efficient Opperation... for a good start. There is a wealth of information out there. And here on this site you will find a wealth of first hand experience unselfishly handed out by the members. It will boggle your mind.

You'r gona have more fun than a barrel full'a  rangatangs.  ;D

Alan

[dgdrls]

"I was told to run it at 550 rpm,s,  is that rim speed, or is that the speed of the shaft?"

If the blade in on the shaft they will be the same, the difference would be distance traveled.

DGDrls

[bandmiller2]

What Alan said is straight scoop,under speed the saw will tend to wobble or chatter in the guides as you speed up you will find its sweet spot it will run true overspeed will tend to snake [slow wobble].If she dosent straighten out it needs to be tensioned.My saw is hammered for 600 as my saw doc dosent like them turning too slow,mine is happy anywhere between 550 and 600 rpm.What is most important is maintaining the speed in the log and not dragging down.Take A hand saw and make a cut at normal speed then try a cut going real slow.Most older mills and saws are happy between 500 to 600rpm large plates to the low end. Frank C.

[1crowfarm]

Hey try ebay for a RPM meter  I bought an old meter there sometime back for less than 10 or 20 dollars Good Luck

[bandmiller2]

Paul what if I count til I get dizzy then multiply buy four.? Frank C.