Grinder build - WARNING: Pic and Text heavy.

[AcridSaint]

Ok folks, I was planning on waiting until this thing was finished before I posted it on here, but I can't contain my excitement. I'll try to update this thread whenever we get something else done, but it's going to be a couple of weeks before anymore serious moves are made. I can't really take any credit for this build, other than having a strong desire for a 2x72 grinder. I've been very fortunate in having Alan Folts around to help me with the build as well as many freebie parts.

We used a large drill press, metal cutting bandsaw and a bader liberally during the process. That being said, the work could probably have been done with a small drill press and an angle grinder, it just would have been slower and more tedious. All of the square tubing had been in Alan's back yard for a couple years and was pretty rusty, we knocked off most of the rust on the main tubing and tool arm with the belt grinder, but it could have been taken off with just some sand paper it necessary. I'll probably knock the rust off of the rest of it this week sometime.

The chasis is 1.75" and 2" square tube with 1/8" walls. The main tube is 13" long, although that was fairly arbitrary, it just looked about right. 12" will surely be ok and make it easier to source new parts if someone tries to do this. The legs are 6" high to the bottom of the main tube and the top of the rear leg is also an arbitrary length, to be shortened once we figure out where the tensioner needs to be. Both legs were cut out on the bandsaw, the rear had to be ground to get squares out of both sides to slide the tube through. Both will be welded in place before the project is done.



The main tool arm is 1.5" square tubing 24" long. All square tubing seems to have a weld on one spot on the inside and this had to be filed down on the chasis tube in order for the tool arm to fit inside. The top is drilled and tapped to attach a solid tooling block and the bottom is drilled and tapped for accessories. I had planned on using just the tube, but Alan pointed out the necessity of a solid block to mount the wheel to. All of the bolt holes on the tool arm are made to fit bader tooling bolts because my contact wheel is a bader and it was just convenient to use one drill and tap

I'm hoping that the length of the arm and the ability to push it out the back of the main tube will allow me to use a variety of belt lengths from 42" up to 132", with some limitations on wheel size, of course. This way I can take advantage of very good deals on belts from folks who used to have a burr-king or 48" grinder like a small coote as well as any sort of freebie or extra great hard to pass up belt deals. In addition, it may open up some options for sourcing belts locally if I am in a pinch and need to get something ground.



The mounting block is designed to take my 8" bader contact wheel and also has a second hold tapped on the side to allow me to attach a platen once it's built.



The idler is yet another part acquired from Alan, I believe he said it originally came from surplus center, but they are no longer available as far as I can tell. This a really nice little idler, it's already slightly domed and has bearings installed. It is a bit wide at 3" and will have to be offset from the contact wheel and drive wheel.



I mentioned that I was planning to pick up a screen door spring for the tensioner and Alan had a great idea to use some shocks that he had picked up. Pressed between your palms, each one of these arms take a good amount of pressure to compress, combined they should provide enough tension rather easily.



The drive wheel is turned from a block of aluminum we found laying around in the shop. It's appr. 2" diameter and should drive my belt at about 2000sfpm with a 3450RPM motor. Just for reference, this is ever so slightly larger than the single speed bader drive wheel. The shaft is a 3' piece of 5/8" steel rod that cost me $9 from lowe's. I'm sure it's not nearly as good as a true hardened steel drive shaft, but it should do well for the time being. I'll cut this down and use the rest for other parts on the grinder as well as my disc grinder project.



The bearings for the drive shaft also came from Alan's stock pile. I have four of them, although I don't think I'll need to use them all.



Here is the current pile of parts, saved the best for last:



There is still quite a bit of work to do, I need to find a base plate, two thick plates to mount the drive bearings to and the parts for the tensioner arm. We still need to build the tensioner, tracking assembly and drive assembly, and a platen, as well as welding everything together. There's surely more to do, but I've done enough writing for now

Comments or suggestions welcome and appreciated.

[NJStricker]

Cap,

Keep us posted and keep the pics coming! I'm building my disk grinder now, I will have to build a belt grinder someday.

Nathan

[AcridSaint]

Nathan, I grabbed a disc up last month or so and planned on building a disc grinder with stuff I had laying around. My motor had the wrong shaft size, however, so I needed to get a new motor or get some drive shaft and pulleys. Either way, I knew I'd have to order parts, so I figured I might as well get a motor from surplus center. That's when I said well heck, I might as well just build a grinder.

That being said, this would not have been nearly as cheap for me if I didn't have access to so many free goodies.

[NJStricker]

That's what directed me toward a disk grinder. I don't have access to freebies, and just got some powertools at a garage sale a couple of weeks ago. I pulled a reversible motor off of a table saw and will use it to drive an old Wards Powerkraft 8 inch disk. I removed the table rest for the disk and rigged up a 6 inch wheel to step down the 1750 rpms from the motor. I hope to finish building the table tonight, then later this week rig up the switches for the reversible part.

[cdent]

Hi Cap,
Extra drive shaft and a couple of bearings you don't need. Sounds like the makings of a disc grinder (if it's 5/8"). Best of luck. Craig

[AcridSaint]

Yep, the disc takes a 5/8" shaft, I was thinking the same thing, just need to pick up one extra pulley with a 5/8" bore. I also thought I might just hang the disc off the other side and use it horizontally.

**I guess that should have said vertically**

[AcridSaint]

Bitter-sweet news today, the motor is on the way, but it's not the one I originally wanted. I was going to get a 2HP Cont. duty motor that could be wired for 115/230, hoping I could get away with running it on 115 for a while in the area I work now. They ran out of them at surpluscenter, which means I'll probably never see it there again. Since I had to get something else I figured I might as well get a 3hp Cont. duty job, so that's what's coming.

Now I just have to put together a new work area with 220. She's a single phase pump motor that I'm going to mount below the grinder and try to throw a dust shield around. It's not TEFC, but it's also a lot less money. If it holds up for a year or better it's a good investment for me because it will allow me to put out so much more work. We shall see.

Pics will be posted when I get the motor.

[cdent]

Hi Cap, I just had a couple low key rookie thoughts. I've used a below grinder motor mount, but when I moved my motor on the bench top, it seems to eat a lot less dust. I've also pulled an old ladies nylon over an open motor and got it to survive better than hoped. A shop (garage) subpanel has been on my wish list for convenient power, but I was able to make a 220 extension cord and use my dryer plug that happened to be close by.
Take care, Craig

[AcridSaint]

There was some 220 hooked up outside before, I just need to reconnect it and setup an area to work near there. It's just going to take a little time and some wife convincing. I'm mulling over the idea of top mounting it, I wonder why it seems to get less dust on top. Either way, the nylons seem like a good cheapo filter, did you notice it getting any warmer?

[Ron Aggus]

Does nylon hose from old ladies work better than nylons from young ladies?.

[NJStricker]

Doubt it. But getting the nylons from a young lady would be more fun.

[cdent]

Hi Cap, It looks like your doing a KMG type design. The grit definitely goes down, and I try to catch some of it with a water bucket tucked close to the bottom going away part of the belt (less grit seems to follow the belt around and come back over the top). On my set up the bottom mounted motor always had a heavy layer of grit on it, when it's up top, if your not getting dusted then the motor's probably getting less. I made ply and light sheet metal deflectors, but it's right in the line of fire down there. Only thing I ever did with the nylon idea was brush it or shop vac it off when it got hard to tell what it was. It also seems to last pretty well, probably better than a year before I notice little rub holes on corners and things (I got mine from my wife or daughters, my 'fun' days are long gone). Don't be too sneaky, but if it's already in place, the Mrs. probably wouldn't notice a couple odds and ends hardware store fittings to get that 220 line powered up again (oops?). You know your going to want to fire it up.
Take care, Craig

[AcridSaint]

Yeah Craig, it's a bit of a KMG style. I had a KMG and a BII to look at when we were making parts, so there's a bit of both in it I suppose. I haven't used the KMG yet, but the bader seems to get most of the grit in the bucket, I hadn't thought about it getting in the motor, was always worried about steel dust. Anyways, I see where you're coming from. Looks like I'll top mount it and throw up a dust cover of some kind in addition to the nylons.

On another note, I was doing some measuring on the chasis last night and I think I'm going to want to cut the main tube down a couple inches, maybe to 11" or 10" if I ever want to use belts smaller than 72". It looked like 60" might be a tight fit on the current size, even if I get the idler pretty close to the arm, so there's no way I could fit anything smaller in a pinch.

[dphipps]

Hey, looks like a good project. What type of contact wheel is that, I'm wanting to mod my grinder to 2x72 and I have been looking for one. I would like to get a 10" wheel but will gladly use an 8". Looking for alternatives to high price and I found a caster company that makes an 8" aluminum wheel with rubber coating and roller bearings for $24.00.

[AcridSaint]

It's a Bader wheel, it needs to be trued and wasn't getting any use, so I managed to score it. New, they run about $200 from trugrit, I don't know who all else sells them. I don't think you'll find a cheaper price than $24, but if you want a true contact wheel, I think the grizzly 10" is about as affordable as they come. You can get one for about $70. It's not cheaper than the 8" you found, but it is 10" and made for knife grinding. Downside is that you won't get any bearings with it since the griz uses the contact wheel as the drive.

What is the rubber hardness on the aluminum wheels? Does the company have a website?

By the way, I've had good success on an 8" wheel, I like the way the grind comes out.