Print Page | Close Window

Miter Saw ??

Printed From: Unofficial Allis
Category: Other Topics
Forum Name: Shops, Barns, Varmints, and Trucks
Forum Description: anything you want to talk about except politics
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=182672
Printed Date: 25 Jun 2024 at 7:27pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com


Topic: Miter Saw ??
Posted By: FREEDGUY
Subject: Miter Saw ??
Date Posted: 20 Aug 2021 at 8:26pm
I run 2 DeWalt 12" non-sliding compound saws that have the motors on the right side of the blade (direct drive ). A guy rolled onto the job site this morning with a DeWalt 12" sliding dual compound saw that had the motor on the left and behind the blade axle (belt driven gear box I believe). Did the gear box change the rotation of the L/H motor, or is the L/H motor running in a different rotation ?



Replies:
Posted By: Jordan(OH)
Date Posted: 21 Aug 2021 at 8:49am
Why not look at it and SEE for yourself?


Posted By: steve(ill)
Date Posted: 21 Aug 2021 at 9:02am
Why would you want a saw that turns BACKWARD and kicks the wood up in your face ?

-------------
Like them all, but love the "B"s.


Posted By: Lars(wi)
Date Posted: 21 Aug 2021 at 9:15am
I am no expert, but my guess is there are cw, and ccw, electric motors.

-------------
I tried to follow the science, but it was not there. I then followed the money, and that’s where I found the science.


Posted By: FREEDGUY
Date Posted: 21 Aug 2021 at 5:44pm
Originally posted by Lars(wi) Lars(wi) wrote:

I am no expert, but my guess is there are cw, and ccw, electric motors.
Thanks for that reply, how are these motors "configured" wire/wise to rotate 1 direction or the other ? Sadly, I'm still unclear on how a 4 stroke engine runs the direction that it does, BUT, I know for a fact that a certain IB Ford engine runs  backwards in a (pretty sureEmbarrassed) in a boat Smile


Posted By: FREEDGUY
Date Posted: 21 Aug 2021 at 5:46pm
Originally posted by steve(ill) steve(ill) wrote:

Why would you want a saw that turns BACKWARD and kicks the wood up in your face ?
Where did you come up with THIS scenario ??? What a BS reply on your part DeadDead !!


Posted By: steve(ill)
Date Posted: 21 Aug 2021 at 6:52pm
and your next question... Why did the chicken cross the road ?  LOL  Thumbs Up

-------------
Like them all, but love the "B"s.


Posted By: steve(ill)
Date Posted: 21 Aug 2021 at 6:54pm
You dont "change the direction " of a 120v motor... You have to have a motor that is WOUND to rotate that direction... There are a few ( very few) motors that have terminals inside that can be switched to change the winding sequence.... 3 phase motors can be run either direction.

-------------
Like them all, but love the "B"s.


Posted By: Jim.ME
Date Posted: 21 Aug 2021 at 8:36pm
Why are you assuming the motor is turning the opposite direction? There are two ends to an armature, which turns the same direction it's entire length. Put a pulley on the opposite end of your direct drive motor, move it straight over and mount it to the left of the saw, belt it to an arbor in the saw blade and it will turn the blade the same direction as it turns now. Just like an engine it will appear to be turning the opposite direction if you look at the clutch instead of the fan.


Posted By: FREEDGUY
Date Posted: 22 Aug 2021 at 5:36pm
Originally posted by Jim.ME Jim.ME wrote:

Why are you assuming the motor is turning the opposite direction? There are two ends to an armature, which turns the same direction it's entire length. Put a pulley on the opposite end of your direct drive motor, move it straight over and mount it to the left of the saw, belt it to an arbor in the saw blade and it will turn the blade the same direction as it turns now. Just like an engine it will appear to be turning the opposite direction if you look at the clutch instead of the fan.
Because of the "AIR INLET " cover on these motors, seems like DeWAlt took a motor mounted on the "right(direct drive)" and mounted it on the "left" of the sliding unit Embarrassed.. I have been into farm duty motors that can have the rotation "changed", BUT, there's a few more terminals in them to "tweak" WinkWink


Posted By: FREEDGUY
Date Posted: 22 Aug 2021 at 5:39pm
Originally posted by steve(ill) steve(ill) wrote:

and your next question... Why did the chicken cross the road ?  LOL  Thumbs Up
 
NO, my NEXT  question is why wouldn't some DUMB ASS turn the blade around in "YOUR" scenario WinkWinkWink


Posted By: jaybmiller
Date Posted: 22 Aug 2021 at 6:08pm
Steve, there are LOTS of AC motors that can be wired CW or CCW, simply by changing 2 wires. Most in the 1-5HP range can do this ( think air compressors,saws,etc.) All of the 120/240 ones I've seen can as well. Only 1 direction only ones are specific use, like water pumps,

as for the original post, I'd have to know the model numbers, to check  'parts diagrams' to see what's going on.


-------------
3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water


Posted By: Kansas99
Date Posted: 22 Aug 2021 at 6:39pm
Originally posted by steve(ill) steve(ill) wrote:

You dont "change the direction " of a 120v motor... You have to have a motor that is WOUND to rotate that direction... There are a few ( very few) motors that have terminals inside that can be switched to change the winding sequence.... 3 phase motors can be run either direction.


You know the one that gets me more than anything I've ever seen is a 3 phase submersible pump.  I don't know anything about electricity but I know a 3 phase motor switches directions by changing any 2 leads of the 3 around, I do this all the time when putting motors on direct drive irrigation wells and I'm still puzzled that there's no neutral.  Anyways I had a 4in 15hp submersible installed on a irrigation well that only produced about 600gpm and when I turned it on the first time it had maybe 150gpm, so called the well shop and told them what was going on and they said sounds like the motor is running backwards.  I asked how it could pump any water if the impellers are running backwards and they told me they can pump some, really? Yep he said just the way there made, switched 2 leads and sure enough 600gpm.  WTHConfused  I guess maybe there is a few backwards impellers to push a little water over the motor to protect it from burning up if it runs backwards?  I sure don't know.


-------------
"LET"S GO BRANDON!!"


Posted By: steve(ill)
Date Posted: 22 Aug 2021 at 7:21pm
On 3 phases motors you have 3 wires.. Call them A-B-C... the Electricity ( rotation ) flows from A to B to C... If you change 2 wires around to make it  B-A-C ... the motor changes direction to go from A back to B back to C.

Jay, i know there are SOME 120v motors that are reversible.. But i would not say a majority.  This would be one of the most "COMMOM " motors above 1 HP sold in the US..( and it is 120/240 v) There are some 240v motors that reverse, but not really common for 120v.




-------------
Like them all, but love the "B"s.


Posted By: steve(ill)
Date Posted: 22 Aug 2021 at 7:28pm
NO, my NEXT  question is why wouldn't some DUMB ASS turn the blade around in "YOUR" scenario...

Turning the BLADE AROUND will NOT make the motor go the other direction !!!

Laughing Smiley Emoji GIF - LaughingSmiley Emoji RollingOnTheFloorLaughing GIFs

I though you knew something about tools ?  Blade rotation is always AWAY from the operator on an overhead saw... It pulls the wood AWAY from your body as it cuts.


-------------
Like them all, but love the "B"s.


Posted By: JTOOL
Date Posted: 23 Aug 2021 at 7:47pm
I just leave electricity to the electricians. That stuff can kill you.


Posted By: TomC
Date Posted: 23 Aug 2021 at 8:46pm
I know two things about electricity, you can't see it and it will kill you. I leave it alone



Print Page | Close Window

Forum Software by Web Wiz Forums® version 11.10 - http://www.webwizforums.com
Copyright ©2001-2017 Web Wiz Ltd. - https://www.webwiz.net