Finally going to delve into a big boy grinder

wall e

Well-Known Member
I have succesfully squirrelled away enough to build my grinder. I just am lost as to which of the entry level vfd's to get. Am planning to use a 110/220 motor so I can wire it for 110 till I get the shop built with the 220 power supply.
Am askin for some advice. I know will I get what I pay for.
 

Wayne Coe

Forum Owner - Moderator
Check out the VFDs on my web site. The KB grinders are the easiest to set up and are rock solid. You definitely want to get a NEMA 4X enclosure. These are not the cheapest VFDs out there but they will last well. Always unplug any electronic equipment when not using it. Anything with a board in it.

While you are at it check out the grinder videos on my web site and consider getting the DVD and build a MOE's Grinder.

Let me know if I can help you.
 

wall e

Well-Known Member
Will do Wayne. I couldn't remember the name of the enclosure but I may be fortunate and my dad can find one thats being updated at the mill he works at.
 

scott.livesey

Dealer - Purveyor
which style grinder are you making? ones similar to the Wilmont LB1000 use a 'C' face motor that bolts directly to the grinder frame. ones that use pulleys and belts need a motor with a foot. IMHO, unless you are mounting your VFD within inches of your grinder, you don't really need a NEMA 4 enclosure. My VFD is mounted 2 feet above and 3 feet to the left of my grinder and has more pollen on the case than grinder dust.
 

Self Made Knives

Well-Known Member
Scott, mine is almost exactly like yours. Up and to the left of the grinder and it stays very clean. My grinder seems to spread its mess pretty much in the plane of the wheels, not really that much side to side. Bucket of water under it catches most of it and I've got a little aluminum deflector underneath, between the contact wheel and drive wheel.
 

wall e

Well-Known Member
I am pondering on what style exactly it would be like I have two sets of prints and also like some of the features of others as well.
As far as motor style I am wanting to do direct drive. Less wheels and bearings as well as a smoother quieter machine.
I have a 1x42 with a belt and is noisy and will rattle tools off the stand.
I see both sides of the vfd and enclosure coin.
 

Sticks

Well-Known Member
I agree with Wayne. I think a KBAC 27D is what I purchased five years ago and it served me well. They aren't inexpensive, at least $350.00 (2008 price), but aside from the NEMA 4 enclosure you will be able to use 110 or 220 volt current. I forgot how it works now, but if you start with 110v and later run 220v it is a simple switch over (jumpers). Also, unless you are handy with electronics (I'm not) it was important to me that it was very simple to set up.

As an aside, I built my grinder from a Polar Bear Forge "Grinder in a Box" kit. I enjoyed building it. I learned how to drill and tap and it gave me time to buy the components, but at the end of the day, after buying the motor (Ebay surplus stock $125.00), the controller, a good contact wheel and drive wheels, etc. I think I saved about $200.00 over purchasing a new Beaumont KMG! It was satisfying to build my own. But I could probably sell the KMG for near what I paid for it. Mine...?

Jay
 
Last edited:

wall e

Well-Known Member
I'm leaning twards a mishmosh of nwg,eerf,kmg and some of my own ideas for a design.
Im wondering though if I was to use a footed motor and just raise it off the base enough to bolt it to some tube or channel why wouldnt it work that way as a direct drive? If all the wheels are inline and true what it the difference between a 65/footed framed motor and a C faced grinder mounted inline and true?
A foot needs 4 bolts to hold inplace and there is a small sheet metal piece that composes said foot.
A C face mounts to a plate with 6 bolts to a plate as a mount.
Torque on the mount is the only difference I can see, a foot is clamped or screwed to the motor and the belt is the space to absorb the excess torque as to not tear up the foot.
The C face is similar to a wheel or ring gear and has larger area to disperse the torque throughout the mounting surface. So that to me can be the only difference between the two.

Side note, we got our new house and sign papers on tuesday. No shop but has a garage with an 8x8 room with U shaped work bench and shelves already installed. Work bench full length of garage so will have space to set up properly a knifemaking area.
 

John Wilson

Well-Known Member
I'm leaning twards a mishmosh of nwg,eerf,kmg and some of my own ideas for a design.
Im wondering though if I was to use a footed motor and just raise it off the base enough to bolt it to some tube or channel why wouldnt it work that way as a direct drive? If all the wheels are inline and true what it the difference between a 65/footed framed motor and a C faced grinder mounted inline and true?

The motor will quickly die of bearing failure at the shaft due to misalignment. You can do what you're talking about if you use a Lovejoy or bendix coupling, but what's the point? C-face mounts were invented to do just this. There's nothing stopping you from trying, but just remember that these little rolled steel frame motors simply won't take any abuse. These motors are classified as disposable in the industrial world.
 

wall e

Well-Known Member
The motor will quickly die of bearing failure at the shaft due to misalignment. You can do what you're talking about if you use a Lovejoy or bendix coupling, but what's the point? C-face mounts were invented to do just this. There's nothing stopping you from trying, but just remember that these little rolled steel frame motors simply won't take any abuse. These motors are classified as disposable in the industrial world.
I understand how disposable motors are in the industrial world. If its only 145 for a new motor w free shipping and a rebuild kit it 75 plus 17 shipping and 2 hrs for an electrician/millwright to rebuild at 20 an hr its a few bucks cheaper to buy a new motor.
The shaft on the footed motor is shorter and a c frame is a few bucks more so why skimp. Thanks for the input
 

coachcampana

Well-Known Member
I love my kmg. There is something to be said for buying a grinder that already has everything lined up perfectly.

Sent from my XT1565 using Tapatalk
 

Self Made Knives

Well-Known Member
If I'm understanding what John is saying, I guess I would disagree with him. We usually see eye to eye on everything that I can remember. Unless you're talking about cheapo Chinese motors maybe, the life of the motor will be the same whether mounted as C-frame or footplate. Many motors come with both options. For a direct drive grinder, the forces on the bearings are the same in either case. My grinder motor is bolted by a foot plate and is direct drive, no problems. Maybe I'm not understanding what you're saying/asking, but I don't see a difference.
 
Don't forget about the tried and true Bader. I did a lot of research before I bought mine but I wound up calling Don Hanson because I knew that he owned several brands of grinders and when I asked him if he could only have one which would it be he instantly replied, "Bader, hands down". On that advice I bought one and haven't regretted it in any way. I recently upgraded to a swivel base and added a surface grinder from Travis Weurtz and now I'm all set.
If you call them and ask for Doug, he sometimes has specials and can save you some $$$. He saved me $400 on a grinder that had a slight "blemish" from shipping damage. I still haven't found the blemish. LOL Doug is also very friendly, knowledgeable, & helpful. He makes knives and hawks and designed a lot of the attachments they sell.
 

scott.livesey

Dealer - Purveyor
i guess the question is how much time do you have and what tools do you have. unless you have access to good machine shop scrap, the 3/8" and 1/2" steel and aluminum plate you need for a nwkmg is very expensive. you are going to need either an industrial grade band saw or industrial grade plasma cutter to cut it. marking, drilling and tapping will probably take at least 8 hours, a lot more if you dont have a good drill press. a bader looks good, but it is $3000 for a basic unit with 1.5hp motor and VFD. if you shop, you can have a wilmont lb1000 or polar forge GIB or oregon blade maker(http://stores.ebay.com/oregonblademaker?_trksid=p2047675.l2563) with the same motor/vfd for less than half. i would install 240vac outlet before doing grinder, as you have many more options for VFDs that if you only have 110vac.
 

John Wilson

Well-Known Member
If I'm understanding what John is saying, I guess I would disagree with him. We usually see eye to eye on everything that I can remember. Unless you're talking about cheapo Chinese motors maybe, the life of the motor will be the same whether mounted as C-frame or footplate. Many motors come with both options. For a direct drive grinder, the forces on the bearings are the same in either case. My grinder motor is bolted by a foot plate and is direct drive, no problems. Maybe I'm not understanding what you're saying/asking, but I don't see a difference.


maybe I'm the one misunderstanding Walt. I took his post to mean he wanted to direct-drive a grinder using a non-C face motor by inserting the motor shaft into the drive wheel stub shaft and then trying to mount the motor via the base plate because it has no C-face. (think large motor / pump mount where both motor and pump are foot mounted and shaft alignment is done with lasers)

in my head I'm seeing a direct-drive KMG where the motor is foot mounted for lack of a C-face mount.

i may be all wrong. I'm sorry if I misinterpreted, Walt.


Sent from my iPhone using Tapatalk
 
Last edited:

Wayne Coe

Forum Owner - Moderator
The motors that I sell have both the C face mount and the foot so that they can be mounted either way. I mount the motor using the foot just as John describes, directly to the table or base. I use a carpenter's square with one leg running along the side of the frame and the other along the foot to make sure that the motor is square to the frame. There is no need to elevate the motor as mentioned above.

Let me know if I can help you.
 

KenH

Well-Known Member
I think what the OP was referring to was mounting a drive wheel on the motor shaft, then bolting the motor to baseplate using the foot base of motor in such a way the drive wheel will be lined up with the rest of grinder..... as Self Made Knives is talking about. There is no reason that won't work like a champ, and will have no more stress on shaft/motor than a 56C motor will have. Ken H>
 

John Wilson

Well-Known Member
Yeah, I think you are right, Ken. I have to stop reading KD late at night when my brain is not engaged. That would work just fine.
 

Wayne Coe

Forum Owner - Moderator
Most all single phase motors can be wired for either 115v or 230v. 3 phase motors can be wired to run on 230v or 460v. You will have to have a 3 phase motor to run with a VFD. The type VFDs that we use takes the single phase power and converts it to 3 phase 230v. Most of the VFDs that we use for 2 hp and less can use either 115v or 230v in and outputs 230v 3 phase. So yes, you can use 115v single phase to power the VFD which will output 230v 3 phase to the 3 phase motor. As a matter of fact, I recommend using 115v single phase to run up to a 2 hp motor. The manual for the KB VFD specifies that you must use 230v for a 2 hp motor, however, that is for heavy, continuous service, such as pumps and commercial air conditioners. We do not normally exceed the "heavy, continuous" use, however, if you did the VFD would just turn off and you can simply turn it back on.

Call me if you need to discuss this further.
Let me know if I can help you.
 
Top