Killed my grinder.

S

SunnO)))

Joined
Nov 16, 2013
Messages
75
I knew its day would be coming soon, as I started getting into slightly larger blades, and getting more proficient at shaping, my workspeed went up, but it looks like my old craftsman 1x42 wasn't up to the challenge anymore. I stalled it last night (only one of five or so times I have stalled it, ever,) and definitely is running at reduced power, now.

Oh well. I am trying to work it so i build my own grinder, KMG style, and still be able to afford the Grizzly. I know it's not amazing, but for some reason I am really attracted to the stand up configuration. Lotsa slack belt opportunity.

Any of you guys have a source for proper eletric motors? The evidence from browsing ebay tells me that single phase anything is considerably more expensive. If any of you have a decent motor laying around that you want to sell? Just post in the thread.

I love upgrades... And new tools... And upgrading tools...
 
What HP and RPM you looking for? I've got a few motors lying around that I'd be happy to donate to a budding maker.
 
I would have to compensate you some way! (and pay for shipping!)

Realistically, 1hp+/1725ish. Single phase 120/240. I am sure 3450 would be fine, too, Ill just have to do the math to figure out the right set of step pulleys to buy. I will build the grinder around the motor, I didn't plan to build it until I had a properly spec'd, reliable motor. Ebay is really a crapshoot with stuff like that. My shop doesn't have three phase power, so that bumped my cost considerably with having to buy a VFD along with the motor. Perhaps there is an avenue I haven't thought to travel yet?


The Craftsman is 3450 with a 5 inch drive wheel. Runs something like 5200SFM. I would definitely like to go slower than that sometimes for handle shaping and tool making. Such a high speed has helped me develop good pressure control, but it's really a bummer hand sanding out burn marks on scales. :-\


I AIN'T GOING BACK TO FILES, I TELL YA. (i will, i just don't want to... Im so spoiled.)
 
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I also guess another fun question to ask is: How would wide hard skateboard wheels be for idlers? I only ask because I have a set and they are just about 2 inches square. Think they're durable enough? High speed bearings that fit are easy to find, too.
 
I've got a Baldor 3/4 1725Rpm and a Dayton 1/2 3450rpm. Btw, your name come from amps, or the band I'm assuming?
 
Do you think 3/4 is enough to run a 2x72? I have good control, not too worried about stalling it out, but I'd be worried about motor life? Maybe im being neurotic.

Name stems from the amps, strangely. I've owned probably 30 Sunn amps over the last six or seven years. Bought, repaired, sold (not just Sunn, but a lot of stuff.)

Had two Model T's, first and second gen as my main amps for a year, then prices skyrocketed. I still use a Coliseum lead for bass in conjunction with an Acoustic 370. Have a few beta leads kicking around... Sold the Sonaro, 2000s, spectre, concert leads/bass, and the coliseum bass.

I was obsessed with them for a while.

Old Ampegs, Fenders, matamps, marshalls, too. At the peak of my buying/selling phase, I probably had 45 heads and combos in the shop?

I sold most of them to older dudes looking to find their lost tone, from the old days. :-)

sorry for the off topicness!
 
Excellent. Then I semi-officially have everything I need to move into the world of big boy grinders. :-)

This excites me.
 
My advice is that you stay away from single phase electric motors. I did what you are about to do now... get a single phase motor and then build the grinder around it... and I now miss the variable speed a lot. I couldn't locate a set of step pulleys locally so I have the driving pulley directly attached to the motor, so I cannot adjust anything to make it faster or slower.

My advice is that you get a 2hp (at least) 3ph motor and a suitable 1ph input/3ph ouput VDF. You will be able to power it from your single phase outlet and will allow you to tweak the speed in any way you want. And no, 3/4hp is not near enough to run a 2x72" grinder.

Right now I am in the process of swaping the single phase motor for a 4hp 3ph motor I got for free (from an air compressor). I just need to get the VDF (chineese, you bet!).

Mikel
 
Skateboard wheels make poor idler wheels, IMHO. Just because someone who has never made ( or probably even used) a grinder say someone on youtube do it isn't a reason reason to follow suit.

The bearings aren't usually as good, and the material isn't what you want. If building a budget grinder, and the cost of good idler and contact wheels is impossible to afford, then use caster wheels and skateboard wheels....but don't expect them to perform like proper wheels, or last nearly as long.
 
They're urethane to my eyes, and hard! I suppose the wear would be a definite factor in using them. I will poke around town and see if I can find some aluminum rod stock.Bearings are not an issue, I actually went ahead and sourced some lithium grease packed high speed machine bearings. I wasn't planning on using the bearings at the skateshop. They aren't sealed, and I've destroyed numerous sets of them in my time skateboarding. :-) I do plan on upgrading as I go to suit my needs, but my main objective is to get back on the road and at least making knives with the bones of a good grinder. I think the 3/4 motor will be sufficient for at least that purpose, and when i go bigger, I can donate it to another new maker... :-)


4hp sounds like a finger eater. I bet it's gonna move some serious air. I've never had variable speed, so I can't miss it. :-)


Also, I really appreciate you'se guys guidance, and offers. Thank you!
 
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Doh!

I'm in Tallahassee, FL. I post mostly from my phone via tapatalk, and the UI is kind of balls for anything other than posting! I'll see what I can do about fixing that!

EDIT: corrected and located! :D
 
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SunnO))) said:
Doh!

I'm in Tallahassee, FL. I post mostly from my phone via tapatalk, and the UI is kind of balls for anything other than posting! I'll see what I can do about fixing that!

EDIT: corrected and located! :D
Click to expand...

Agreed. The latest update nixed the ability to see anyone's location in their profile. That's just stupid.

Still, it's better than carting my laptop with me everywhere I go.

Post pics of the grinder when you get it done. :)
 
Mikel_24 said:
My advice is that you stay away from single phase electric motors. I did what you are about to do now... get a single phase motor and then build the grinder around it... and I now miss the variable speed a lot. I couldn't locate a set of step pulleys locally so I have the driving pulley directly attached to the motor, so I cannot adjust anything to make it faster or slower.

My advice is that you get a 2hp (at least) 3ph motor and a suitable 1ph input/3ph ouput VDF. You will be able to power it from your single phase outlet and will allow you to tweak the speed in any way you want. And no, 3/4hp is not near enough to run a 2x72" grinder.

Right now I am in the process of swaping the single phase motor for a 4hp 3ph motor I got for free (from an air compressor). I just need to get the VDF (chineese, you bet!).

Mikel
Click to expand...

Step pulleys are the way to go if your trying to keep the grinder set up cheap, and want variable speed. Even if there is no local step pulley's in the area a 2 second search on the internet will provide a lot of sources that will get it to your door in a few days. So to write it off completely makes no sense. Also a 3/4hp motor is strong enough IF you get a good one. A china motor wont work well but I have a 3/4 Baldor that has more than enough power. The power it takes to stall it is way beyond what it takes to grind blades. All this craziness for big huge motors seems kind of silly.(For a starter rig) You get a good motor and you dont have to worry about it. These are my opinions anyway.
 
I was actually planning on step pulleys, I believe one of the other gentleman that responded suggested I go higher power/VDF.

I, too, think the Baldor would be more than sufficient to get me grinding (or get it grinding on me if im not careful!) hopefully the wonderful user that offered it up wishes to part with it for a fee and some intense gratitude! ;):cool:
 
There is also a variable speed pulley system. It is all manual controlled so you don't need to hook up 3phase wiring at all. I will post a picture of it when I get home. Basically you crank the handle and the motor moves back and forth on a base, and in doing so the tension of the belt changes the size of the pulley making it different speeds based on how close or far away the pulleys are to each other. I hope that explanation made sense.
 
That sounds interesting, got a link? Any thing else i should make/take into account before I get crackin'?
 
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