I Want A New Grinder

colu41 said:
If I were to get a single phase motor, could anyone tell me why something like this wouldn't work? I know VFD is the proper way to go, but honestly, I don't need such fine tuning as the vfd would offer.
http://www.harborfreight.com/media/...b33525d08d6e5fb8d27136e95/i/m/image_18028.jpg
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http://www.bladeforums.com/forums/showthread.php/907695-Slow-down-motor-with-rheostat

http://www.bladeforums.com/forums/s...-down-my-belt-grinder?p=12385618#post12385618





http://www.harborfreight.com/router-speed-control-43060.html

This router speed control works with any universal AC/DC brush-type motor, 15 amps or under, to give you control over your router speed. The result is longer bit life and better results depending on the application. Featuring a three-way rocker switch, the dial controls router speed as you work on wood, plastic and even aluminum.

Plug your router into the control unit and you instantly have a variable-speed tool
Works with any universal AC/DC brush type motor, 15 amps and under
6 ft. cord
Click to expand...

The motors you will use do not have brushes.

You will smoke the motor, maybe the controller too.
Spend that money on stuff that will work instead.


If a $20 control worked, do you think anyone one would ever spend the $400 on a VFD ?
 
12345678910 said:
http://www.bladeforums.com/forums/showthread.php/907695-Slow-down-motor-with-rheostat

http://www.bladeforums.com/forums/s...-down-my-belt-grinder?p=12385618#post12385618





http://www.harborfreight.com/router-speed-control-43060.html



The motors you will use do not have brushes.

You will smoke the motor, maybe the controller too.
Spend that money on stuff that will work instead.


If a $20 control worked, do you think anyone one would ever spend the $400 on a VFD ?
Click to expand...

Thanks. Ok I can get that out of my head. So I should just break down and get the motor and vfd that Ken suggested? Screw it, I may as well do it right.
 
Ken H> said:
Yep, do it right, hurt once, then be happy {g}
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Bad thing is that VFD is out of stock at the moment. :grumpy:

Quick question, is $110 shipped an ok price for an aluminum wheel set? 4" Crowned drive wheel, and 3 2" wheels w/ installed bearings and all the bolts, nuts and nylon washers.
 
Yep, it is 2hp. I didn't see the 3hp with my quick search of ebay, either 2hp or 4 hp, so I linked the 2hp unit. Yes, I do think it would work just fine.
 
colu41 said:
Quick question, is $110 shipped an ok price for an aluminum wheel set? 4" Crowned drive wheel, and 3 2" wheels w/ installed bearings and all the bolts, nuts and nylon washers.
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I missed that part of question until just now. Good price? If it's the best price you can find, I guess it's a good price. Buying complete sets like that tend to run price of grinder up. I used 3" longboard wheels rated 72 duro I think they are for the platen wheels, and can also be used for tension wheel - I think the price was $15 or $20 for the set of 4, but then you still need the 4" drive wheel. "IF" you plan on a 1725 rpm motor, then you'll want at least a 5" drive wheel to get higher belt speeds.

I think at $110 with it including all the hardware, bolts, etc - that's not a bad price. With longboard wheels you'll use 5/16" axles rather than the normal 1/2" axle. I'm "assuming" "all bolts" means the bolts for the wheel axles? Just screw into threaded holes in platen?

Ken H>
 
Ken H> said:
I missed that part of question until just now. Good price? If it's the best price you can find, I guess it's a good price. Buying complete sets like that tend to run price of grinder up. I used 3" longboard wheels rated 72 duro I think they are for the platen wheels, and can also be used for tension wheel - I think the price was $15 or $20 for the set of 4, but then you still need the 4" drive wheel. "IF" you plan on a 1725 rpm motor, then you'll want at least a 5" drive wheel to get higher belt speeds.

I think at $110 with it including all the hardware, bolts, etc - that's not a bad price. With longboard wheels you'll use 5/16" axles rather than the normal 1/2" axle. I'm "assuming" "all bolts" means the bolts for the wheel axles? Just screw into threaded holes in platen?

Ken H>
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Yes. But I may have decided to just get the 4" drive wheel and 2" tension wheel. Ill find some longboard tires that will work.
I also stopped at my local steel shop and got all the tubing and plate that I need for $30!! Pretty excited about that
 
Congrats on such a good price on the metal, AND finding the 1-1/2" ID square tubing! I do hope you got a few feet of that - it's hard to find!

The 5/16" bolts (perhaps a high grade steel?) will work just fine for the axle on the longboard wheels. Just put sufficient spacers (washers?) between inside bearing and platen to provide support should be just fine.

Looking forward to pics of your progress.

Ken H>
 
Ken H> said:
Congrats on such a good price on the metal, AND finding the 1-1/2" ID square tubing! I do hope you got a few feet of that - it's hard to find!

The 5/16" bolts (perhaps a high grade steel?) will work just fine for the axle on the longboard wheels. Just put sufficient spacers (washers?) between inside bearing and platen to provide support should be just fine.

Looking forward to pics of your progress.

Ken H>
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Thanks. I hope to get the entire frame together this weekend.
 
Question about the longboard wheels. The 4" drive wheel is crowned, do the others need to be also? Theres round wheels and theres flat wheels. I'm not sure which to buy. They size them by MM but I'm guessing thats NOT surface contact.
 
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You want the flat wheels - two things to look at are the width of the flat surface and diameter of wheel. The best wheels I found were 50mm wide and I "think" 75mm diameter. I'd think any wheel in the 50 to 55mm wide and 65 to 75mm diameter would be good - even a 50X50mm wheel.

The width in mm is the footprint (or surface width) of the wheel - or that's how the wheels I got were listed.

Ken H>
 
FYI, a larger VFD can run a smaller motor, but you shouldn't try to run a larger motor with a smaller VFD.
 
Ken H> said:
Here is your 3hp VFD for $128 shi pped http://www.ebay.com/itm/300652886556
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Yes that was the original you linked. And its back in stock!! It was out of stock for a few days.

knife to a gunfight said:
FYI, a larger VFD can run a smaller motor, but you shouldn't try to run a larger motor with a smaller VFD.
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And thats good to know. Now that the 3hp is back in stock I may just go with that one. Same price either way.


Also, can someone tell me where I can find a 30# compression spring to fit my 1 1/2 tubing?? I can't seem to find one anywhere! And also, what should I use for the platen? The plans I have call for a piece of 2x2 Angle Iron. But I was thinking of putting something on top of it. Do people use ceramic or something on the lines of that?
 
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Keep in mind that a springs "compression weight" varies with deflection. IIRC, a 6" spring that exerts 30lbs fully compressed will exert only 15 lbs if compressed 3".
Keep that in mind when selecting a spring.
 
Going off of the plans I have, its a 3/4" x 4" springs that compresses 1" with 30# of pressure. I don't even know where to look for one. Or how to even search for that?
 
+1 on longboard wheels. I've been using them for a couple years now and still have zero problems with them, and they work great as contact wheels as well. I used "Abec 11 Grippins" on mine and they work perfectly and are exactly 2" wide. Just buy a set of normal skateboard bearings from any skate shop online or elsewhere and they will fit. The size bolt that fits throught the bearings is 5/16", and get some bearing spacers as well to use between bearing and nut (same as bushings).. I actually put a few washers that are about the same diameter as the bearings (not too big so they don't run on the wheel) for when I neeeded to space the wheels out further away from the side of the platen attachment in order to get all the wheels on the grinder lined up.. everything works great! Here is the same wheel(s) I used: http://www.nordboards.com/ab1170grlowh.html?productid=ab1170grlowh&channelid=FROOG

And here is a short vid on my grinder with those wheels:
[video=youtube;aNMuKGMcqlc]https://www.youtube.com/watch?v=aNMuKGMcqlc[/video]

~Paul
My YT Channel Lsubslimed
 
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Paul - I KNOW I posted this last night, because I remember typing this up because I talked about how well I liked the pretty green wheels, and how good the tracking is. VERY good job.

Oh, I'll bet I typed it up on shop computer, and never hit the post button and it's still sitting on shop computer waiting for me to "post".... Oh well -

Ken H>
 
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