Replies

1. 
   uncommontree | Aug 19, 2002 06:20am | #1

   Mike_in_Katy

   Back about 2 weeks ago I posted to F_G about single speed routers, like my fathers Makita plunge. She suggested plugging the router into a speed regulator. It turns your router into VS. Cant you use a old or new motor of your choice and one of these  VS controls to bring your speed down, you could then make your own slow speed grinder . This would do the same thing would it not. Wouldn't this work on a normal 110 V. grinder? What do you think ?  Have a great week all Rick................

1. 
   PlaneWood | Aug 19, 2002 08:12pm | #3

   Adesigns -

   If you slowed a router down from 25,000-28,000 rpm to 1000 rpm, you have no torque left.

   My lathe is belt driven and has 6 speed settings.

   PlaneWood by Mike_in_KatyPlaneWood

1. 
   riverr1 | Aug 19, 2002 09:06pm | #4

   You also have to be careful that your motor is capable of operating with a variable speed attachment gizmo. For one example, for capacitor induction start motors, the start windings shut down and the main windings take over when about 75% of required power is reached. Start running the motor at less then 75%, the start windings will never shut down. Kind of like turning the key in a car to start a motor that is already running.

   It will work fine for some motors, others not so you need to find out. The duty cycles of a motor usually have an "S" 1 through 8 designation, but there still may be other considerations.

1. 
   RSRose | Aug 19, 2002 09:58pm | #5

   The variable speed motor controllers that are sold for "routers and electric drills" only work for "uinversal motors" (AC/DC) motors. All such motors have brushes as opposed to induction motors which do not use brushes and are used to drive table saws, bandsaws, jointers, lathes.

   Induction motors can only be varied in speed by controlling the frequency of the current. Such a speed controller is an expensive piece of equipment, and costs more than most high end routers. Induction motors (single phase) use capacitor start circuitry. Universal motors have no such components.

   The universal motor speed controllers will not work with induction motors and may damage the start up circuitry, be damaged themselves, or simply blow their fuse, depending on their design.

   When controlling a universal-type motor, the speed controllers maintain high torque at low RPM.

   Rich

   Edited 8/19/2002 3:00:13 PM ET by Rich Rose

1. 
   riverr1 | Aug 19, 2002 10:42pm | #6

   Rich,

   I agree, but didn't this start out with a Lathe? That's not a hand tool and VS might be an issue here. Thanks for clarifying where they do and don't work.

   Don

   Edited 8/19/2002 3:43:42 PM ET by Don C.

2. 
   RSRose | Aug 19, 2002 10:51pm | #7

   Don,

   That was my point - if the lathe is powered by an induction motor, an "ordinary" speed control box will not work.

   Rich

3. 
   riverr1 | Aug 19, 2002 11:04pm | #8

   Rich,

   Yep, that's why I, and I'm sure others, appreciated your clarifications. Somwhere during the thread, lathes, rounters and grinders seemed to get bundled together by the job to be done and not the tools doing the jobs.

   I believe "S1" is the designation for a universal motor. Could be wrong though.

   Don

   Edited 8/19/2002 4:06:24 PM ET by Don C.

4. 
   uncommontree | Aug 21, 2002 05:12am | #12

   Rich....

   Thank you for clearing up my question (thanks to everyone who helped also) My father has a grinder in his shop that he built several years ago. This grinder is on a plywood stand with the motor located below  I am not clear on the right terminology but hang with me, the grinder part is mounted on a plywood top with a central pulley that supplies all the power to both wheels. Can you or can you not simply change the size of the lower pulley thus slowing down your grind without loss of torque. I do now understand why you cannot change the speed of certain types of motors. This is one of the reasons why I love this site. Very helpful. Thanks all Rick........

2. 
   GeeSeaWhy | Aug 19, 2002 09:06am | #2

   Pity you didn't post this a week ago - I just spent $100 on a 1750 rpm 8in grinder after I burnt out my old 6in Chinese Cheapie! Oh well - anybody need a couple of 6 x 3/4 alum. oxide grinding wheels? I don't see why you idea shouldn't work although I haven't heard of that variation before. Driving a disc sander with the lathe yes, but not making a belt sander out of it.

   Graeme

3. 
   PlaneWood | Aug 20, 2002 02:33am | #9

   Got a 120 grit 30" belt today at HD (the finest grit they had) and gave it a try.  It works to my satisfaction.  I had to put a slight bevel on the leading edge of the block in order to get the belt on.

   I'm using the belt and pulley arrangement on my lathe to control the speed.

   PlaneWood by Mike_in_Katy
   PlaneWood

4. 
   PlaneWood | Aug 20, 2002 04:30am | #10

   Don - guess maybe u took that wrong??  All is was saying was that with a pulley and belt arrangement all you have to do is try another pulley size and if it don't work, then go back to the first one.  No math there.  In my case with the BS, it worked.  I guess I was just expressing suprise of how the subject had gotten changed.  I may have replied to your note, but the reply was not directed to you.  That was just a means to get a note posted.

   Which brings up a point - is there a way to reply to the thread, in general, without replying to an individual??  This note says that it is a reply to you, but in fact I want it to be a reply to the thread.  And, not have to go back to the top and reply to my original note.

   Now, I'm changing the subject!!!!  Some days u can't win!

   PlaneWood by Mike_in_Katy
   PlaneWood

1. 
   riverr1 | Aug 20, 2002 04:39am | #11

   Mike,

   You posted this before you realized I deleted it. After thinking about it I came to the conclusion that it wasn't personal and I over reacted. Sorry about that, it's usually not my nature and may have come out because of some of the tone that was used in that other thread. Again, my apologies. Not sure of the how to post to anyone particular thing.

   Don

2. 
   GeeSeaWhy | Aug 21, 2002 09:39am | #13

   Mike, let's see if this works. I hit Reply on your message with "Which brings up a point - is there a way to reply to the thread, in general, without replying to an individual?? " in it. On the reply page it has From: GEESEAWHY and To: with a drop-down list. Open the drop-down list (click the up/down arrow) and select ALL.

   And Post...