KMG Grinder Questions

B

bjtiger75

Joined
Dec 28, 2009
Messages
51
Alright fellas I think I have finally convinced the wife to let me break down and buy a grinder. I am going to have a budget of about $1800-2000 for the grinder. With this budget how would you have a KMG setup? Would you variable speed with less accessories or would you go 3 speed with more accessories? I already have disc sander and a drill press so I think this is going to be where I sink my money. Also, would you buy a new motor through Beaumont or would you buy new elsewhere or buy used? I do not currently have 220 run in my workspace, but I believe I can have it done for free by a friend that teaches electricity at one of the local community colleges. Do I really need the 220 or would a 1.5hp motor work fine? I plan on mainly doing flat grinds, but would also like the ability to do convex and hollow grinds also. I would really like to hear some of your opinions on this. Also, I think that at this point the NWG is not something I want to tackle even with a kit because at some point I would like to be able to purchase the MAP arm for the KMG.

Thanks,
BJ
 
I would go full VS


KMG-8
8" Grinder Package:
Includes: 1 tool bar,1 platen attachment, 1 work rest, and 1- 8" smooth contact wheel
$920

VS-VFD-2.0
2 hp Variable Speed motor and VFD package. Requires 220V only single phase power.
$814

(if buying from KMG - 1.5 and 2 hp is the same price..so pick 2hp
and get the free friend to work allow a couple hundred for wire, outlet, plug, breaker...
200

SWF Small wheel attachment
$83

SWR-.750 3/4" diameter small wheel
$60

Motor pulley: MA50X5/8 (5" dia x5/8 bore) $22

Grinder pulley: MA25X3/4 (2-1/2" dia X 3/4" bore) $16

Drive Belt: A-23 $9.50

the VFD Rob sells is the KB electronics KBAC-27D
the motor is a Leeson
You may be able to save $1 or 200 on the VFD and Motor package by buying elsewhere.
there seems to be more latitude in motor prices than VFD with different brands / used etc.

workrest, toolbars, mounting bases, I assume you can buy local steel and make them - saving on shipping heavy steel.

Typical shipping costs for these examples are about $140-$160

and spend more on small wheels as you can spend it.
 
IMHO, variable speed is an excellent choice. Now, unlike some folks here, I don't think that the extra money spent on a sealed (NEMA 4) VFD is needed. I took a NEMA 2 VFD and put it into a sealed box. I've never had a problem with it, and it saved me at least a couple hundred bucks.

Don't forget, you'll need some money for belts too ;)

-d
 
Go variable speed. Let Rob send you the full set-up. Variable speed is SOOOOOOOOooooooooo nice. You can always add later.

My set-up includes the 8" wheel with tooling arm (I also have a 10", but want a 14").

Small Wheel attachment with tooling arm with 1/2", 5/ 8", and 3/4" wheels.

Flat Platen with tooling arm.

Rotary Platen with tooling arm.

MAP arm assembly from Michael Canter.

Get started with a variable speed, then add to your toy list as time (and sales) allow.

Can't beat Rob's KMG, especially the Variable Speed.

Just my 2 cents tossed at ya.

Robert
 
I made the plunge to a KMG last summer. I am SO GLAD I went with a variable speed set up! It makes grinding so much easier when you are able to control the belt speed.

If you get a 1.5 HP motor and a KBAC-27 you can run it off of 110VAC

I went with a Flat Platen and 8" wheel set up. I think I would choose a 10" wheel if I was doing it over again.

If you want to enjoy all the attachments make sure to get a tooling are with each one. It makes changing attachments a breeze.

KBAC-27D the cheapest I found. http://www.state-electric.com/

Another source; http://www.solidstatedrives.com

Here is where I picked up my motor;

http://www.electricmotorwarehouse.co...hbase_TEFC.htm

I got the 1.5 HP 1725 RPM item # 110918

Be Aware that some of the places that sell the KBAC require you buy a switch kit which adds to the price!

Also Metal Dust + Electricity = Short Circuit. I would stick with a NEMA 4 enclosure if you want to grind away worry free.
__________________
 
Last edited:
deker said:
IMHO, variable speed is an excellent choice. Now, unlike some folks here, I don't think that the extra money spent on a sealed (NEMA 4) VFD is needed. I took a NEMA 2 VFD and put it into a sealed box. I've never had a problem with it, and it saved me at least a couple hundred bucks.

Don't forget, you'll need some money for belts too ;)

-d
Click to expand...

+1 for making your own enclosure, saved a bunch of money.

http://www.factorymation.com/s.nl/it.A/id.198/.f

http://www.grizzly.com/outlet/Motor-2-HP-3-Phase-3600-RPM-TEFC-230V-460V/G6243 Yes I know it is a 3600rpm motor...
 
Baldor 2 hp 3ph STAINLESS STEEL motor off ebay $100
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220557736004&ssPageName=STRK:MEWNX:IT
Yaskawa J1000 VFD brand new $350
I have multiple setups in my shop like this and they all run flawlessly.
You can get almost new 3ph motors (not stainless steel) for under $50 if you look.
In addition to the motor linked above, I got a new 1.5 HP 3ph Leeson Stainless motor or $13 plus shipping.
That will never happen again but if your patient and make offers you will be surprised what you can get for very little money.

If you can connect a few wires to a screw terminal you can connect a VFD.

Michael
 
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Thanks for the input fellas. It looks like I am going to have to with a 1.5hp motor because the wire and everything to run the 220 would break my budget because it is over 150 feet to the breaker box.

I am going to call Rob over at Beaumont and start getting together what I want.

Any other questions I should ask or any must have accessories?

BJ
 
Did you all buy a motor that is built to run at variable speed or just a regular motor? I ask because regular motors will burn out if they are ran at lower speeds all the time especially if they are not ran in 3 phase.
 
montana guy, if you're trying to run a single phase motor with some sort of motor speed controller, then yes, you will probably burn up your motor, not to mention that you won't have any toque available. When people talk about variable speed setups with KMG's and other grinders, they're either talking about a single phase motor and step pullies, a three phase motor controlled with a VFD, or a DC motor with speed control

--nathan
 
Quick heads up - if you're willing to build a protective enclosure for your VFD, http://www.dealerselectric.com lists a TECO FM50-202-C (220VAC/1ph to 230VAC/3ph, 2HP, IP20 enclosure) for $144.

BUT when I ordered the guy told me what they have in stock is GE-branded, same exact VFD as the TECO and made by TECO, and it goes for $126.

Also, I just bought a brand-new Baldor CM3554 (1.5HP, 5/8" shaft, TEFC, 56C frame, 1725rpm) for $165 shipped to my door. There are a lot of new-surplus 3ph motors on eBay right now, cheap.

All told, my variable-speed 1.5HP setup will cost me less than $400, including wiring, plugs, and protective enclosure.
 
drdoc said:
Quick heads up - if you're willing to build a protective enclosure for your VFD, http://www.dealerselectric.com lists a TECO FM50-202-C (220VAC/1ph to 230VAC/3ph, 2HP, IP20 enclosure) for $144.

BUT when I ordered the guy told me what they have in stock is GE-branded, same exact VFD as the TECO and made by TECO, and it goes for $126.
Click to expand...


this one ?
http://dealerselectric.com/item.asp?cID=&PID=1025

So how do you control speed ?

Can you turn a pot, or do you have to press the up down buttons?
Is a remote pot possible ?
Is it reversible for a disc grinder?

I looked for a manual online, but not yet found one.

http://www.jamescoxandsons.com/DownLoads/FM%2050%20Instruction%20&User%20Manual.pdf

This manual ?
 
Last edited:
drdoc said:
Quick heads up - if you're willing to build a protective enclosure for your VFD, http://www.dealerselectric.com lists a TECO FM50-202-C (220VAC/1ph to 230VAC/3ph, 2HP, IP20 enclosure) for $144.

BUT when I ordered the guy told me what they have in stock is GE-branded, same exact VFD as the TECO and made by TECO, and it goes for $126.

Also, I just bought a brand-new Baldor CM3554 (1.5HP, 5/8" shaft, TEFC, 56C frame, 1725rpm) for $165 shipped to my door. There are a lot of new-surplus 3ph motors on eBay right now, cheap.

All told, my variable-speed 1.5HP setup will cost me less than $400, including wiring, plugs, and protective enclosure.
Click to expand...


I have been looking into what motor setup to get for my grinder build and thought the costs were too prohibitive to go with a vfd setup. From what I have read in this thread is that you can use a standard single phase household 220v line hook it to one of these $125 phase converters (properly protected from the dust) and connect it to a 3ph surplus motor to get a workable vfd setup. It seems like it will only cost a little more that buying a single phase 1 speed 2hp motor.

I was almost set on the NWG and step pulleys but I really wanted to do the "grinder in a box" but had reservations about buying a 3450rpm motor and not being able to reduce the speed when needed (like on the NWG/step pulley setup) because it is a direct drive pulley on motor shaft setup.

I was limited to looking at the 1 phase 120v motors but this opens up looking for 3ph motors. There was a guy on Craigslist locally that had a TON of TEFC industrial motors for cheap that I passed on because I thought 3phase motors were out of the picture for my setup. No where did I put his phone #????:D
 
Wloch248 said:
I have been looking into what motor setup to get for my grinder build and thought the costs were too prohibitive to go with a vfd setup. From what I have read in this thread is that you can use a standard single phase household 220v line hook it to one of these $125 phase converters (properly protected from the dust) and connect it to a 3ph surplus motor to get a workable vfd setup. It seems like it will only cost a little more that buying a single phase 1 speed 2hp motor.

I was almost set on the NWG and step pulleys but I really wanted to do the "grinder in a box" but had reservations about buying a 3450rpm motor and not being able to reduce the speed when needed (like on the NWG/step pulley setup) because it is a direct drive pulley on motor shaft setup.
Click to expand...

This is exactly how I had been looking at it. I really like the DIY-in-a-box concept, but looking at eBay prices for VFDs and dealer prices for motors kept coming up in the $600-700 range.

Then a machinist friend turned me onto dealerselectric.com for the VFD, and I accidentally found the secret to shopping for motors on eBay: search on the motor BRAND NAME, like Baldor, Leeson, Marathon, etc. Searching on 2hp, 3ph, electric, whatever, just wasn't bringing up the good listings.
 
drdoc said:
This is exactly how I had been looking at it. I really like the DIY-in-a-box concept, but looking at eBay prices for VFDs and dealer prices for motors kept coming up in the $600-700 range.

Then a machinist friend turned me onto dealerselectric.com for the VFD, and I accidentally found the secret to shopping for motors on eBay: search on the motor BRAND NAME, like Baldor, Leeson, Marathon, etc. Searching on 2hp, 3ph, electric, whatever, just wasn't bringing up the good listings.
Click to expand...


I had been searching ebay for 2hp, etc now I can do it right! Thanks!
 
Here's how I have mine set up:

IMG_0396.jpg


IMG_0399.jpg


IMG_0400.jpg


And I have the VFD switched to control my KMG, my disc, and my EERF 2x72":

switchbox.jpg


--nathan
 
this use of the VFD inverter for different tools is very interesting. it's a shame to spend a lot of money and use it only for one tool.
 
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