D.C. scr drive speed control for die grinder

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: D.C. scr drive speed control for die grinder

Post by Carnut1 »

Circlotron wrote: Mon Apr 29, 2019 12:04 am
Carnut1 wrote: Sun Apr 28, 2019 12:08 pm I want to try a v.f.d. but I doubt the field windings could handle it.
I wouldn't expect a VFD to do anything useful driving a brush motor. Those motors are insensitive to AC supply frequency as shown by the fact that they will also run on DC.
I do vfd speed controlled 480 volt 3 phase induction motors and controls at work quite a bit. When purchasing a motor that will be powered by a vfd you need to specify vfd rated insulation due to the impulses generated by the vfd. Many motor companies are moving to all their motors with this insulation class. These motors have a definite ringing sound when the start and run. Thanks, Charlie
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: D.C. scr drive speed control for die grinder

Post by Carnut1 »

ClassAct wrote: Sun Apr 28, 2019 8:52 pm
Schurkey wrote: Sun Apr 28, 2019 7:06 pm
modok wrote: Sun Apr 28, 2019 6:02 pmThe advantage of electric tools is they are an order of magnitude more efficient than air tools.
So it's a matter of paying less for electricity--powering the grinder directly vs. powering the 5+ HP motor on the compressor? Valid point. For myself, I'll pay the electric bill rather than heft around a heavy, bulky die grinder.


I port with both and almost never use an electric grinder. I have way more control with air, the grinder is lighter and the compressor is outside so I don't hear it. Even if I did have to hear the compressor, I'd still use air.
Class, if I remember correctly you have a H.F. electric die grinder? In my opinion it can not be compaired to a new style Dewalt or old aluminum Makita die grinder. I found the H.F. heavy, gutless with horrible runout. Basically unusable. Thanks, Charlie
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
ClassAct
Guru
Guru
Posts: 1024
Joined: Wed Dec 05, 2018 11:55 pm
Location:

Re: D.C. scr drive speed control for die grinder

Post by ClassAct »

Carnut1 wrote: Mon Apr 29, 2019 6:33 am
ClassAct wrote: Sun Apr 28, 2019 8:52 pm
Schurkey wrote: Sun Apr 28, 2019 7:06 pm
So it's a matter of paying less for electricity--powering the grinder directly vs. powering the 5+ HP motor on the compressor? Valid point. For myself, I'll pay the electric bill rather than heft around a heavy, bulky die grinder.


I port with both and almost never use an electric grinder. I have way more control with air, the grinder is lighter and the compressor is outside so I don't hear it. Even if I did have to hear the compressor, I'd still use air.
Class, if I remember correctly you have a H.F. electric die grinder? In my opinion it can not be compaired to a new style Dewalt or old aluminum Makita die grinder. I found the H.F. heavy, gutless with horrible runout. Basically unusable. Thanks, Charlie
I actually have a Craftsman electric grinder and a Mikita which I don't remember the model.
tt 383
Expert
Expert
Posts: 521
Joined: Wed Nov 19, 2008 8:46 pm
Location: Stuart, Florida

Re: D.C. scr drive speed control for die grinder

Post by tt 383 »

Often wondered if something like this would be a solution
https://www.woodcarverssupply.com/110V- ... fo/799001/
They have a tabletop/hanging rotary tool with handpiece that accepts 1/4 shank too just don't know if it will hold up to the abuse of porting...
Last edited by tt 383 on Mon Apr 29, 2019 12:09 pm, edited 1 time in total.
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: D.C. scr drive speed control for die grinder

Post by Carnut1 »

ClassAct wrote: Mon Apr 29, 2019 11:41 am
Carnut1 wrote: Mon Apr 29, 2019 6:33 am
ClassAct wrote: Sun Apr 28, 2019 8:52 pm



I port with both and almost never use an electric grinder. I have way more control with air, the grinder is lighter and the compressor is outside so I don't hear it. Even if I did have to hear the compressor, I'd still use air.
Class, if I remember correctly you have a H.F. electric die grinder? In my opinion it can not be compaired to a new style Dewalt or old aluminum Makita die grinder. I found the H.F. heavy, gutless with horrible runout. Basically unusable. Thanks, Charlie
I actually have a Craftsman electric grinder and a Mikita which I don't remember the model.
pm me the model of that Makita. I may be interested in buying it from you. Thanks, Charlie
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: D.C. scr drive speed control for die grinder

Post by Carnut1 »

tt 383 wrote: Mon Apr 29, 2019 12:07 pm Often wondered if something like this would be a solution
https://www.woodcarverssupply.com/110V- ... fo/799001/
These usually just reduce voltage which kills the torque.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
tt 383
Expert
Expert
Posts: 521
Joined: Wed Nov 19, 2008 8:46 pm
Location: Stuart, Florida

Re: D.C. scr drive speed control for die grinder

Post by tt 383 »

Carnut1 wrote: Mon Apr 29, 2019 12:09 pm
tt 383 wrote: Mon Apr 29, 2019 12:07 pm Often wondered if something like this would be a solution
https://www.woodcarverssupply.com/110V- ... fo/799001/
These usually just reduce voltage which kills the torque.
Ohh, ya thats no good then.
Post Reply