Grinder Page

Here is where I will document my efforts to build a 2" by 72" belt grinder. I am borrowing heavily from the design of the KMG grinder available at Beaumont Metal Works. I have bought the drive & tension pulleys from there and have bought many other things, like pillow block bearings, and step pulleys in the past for the power hammer project. Rob sells complete grinders or all the parts needed to build your own.

Here we go. Thursday, April 6th, 2006. Day One.

I started the day by going to KH Metals in Riverside to pick up some steel for this project and a couple others. They sell pre cut plate in various sizes and thickness, so I got a piece of 24 inch square plate, 3/8" thick. I figured that would be ok for this. I also bought some 1inch solid bar for the arms, and some 3/16" thick wall tubing for the bar to slide into. There is a little slack, so I also picked up some 1/8" thick by 3/4" flat stock to add onto the bar and take up the space. I also found a couple nice pieces of heavy angle iron that were remnants, so the price was right. We'll see how this works later. Hopefully I didn't waste a lot of time and money.

I've been gathering other parts for this grinder for about 2 years. I bought the motor that long ago when it was on sale. I recently stepped up my acquisitions and bought several different wheels and pulleys back in January that I thought might work. Some will, and some won't. I'll ebay all the left over's when I am done probably.

This week I ordered the tension and drive pulleys from Rob at Beaumont Metal Works, and ordered a couple of belts from Jantz Supply, so I would have something to run on it. I've started putting things together while waiting for these final parts to arrive.

Here is a picture of the KMG grinder so you know what my inspiration was.

As you can see, it is a very nice grinder, and very well made. Unfortunately, I just can't afford to buy one. I also got a lot of inspiration from a nice group at MSN called "Home or shop made Grinders." They have lots of pictures there of various guys interpretation of how to build a grinder. Many of them are pretty incredible. I am borrowing little bits of many of them as well. The final inspiration is just my own creativity as I go along. I don't have any kind of drawing really. Just some scratch on the back of an envelope so I could make sure I had the basics down. I build things pretty seat of my pants, and this grinder is no different. I don't hide my mistakes either, so I will document those as well as I go along so maybe it will help others avoid them.

Here is the drive section. I used a heavy piece of angle iron as the main support. You can see the bearings and pulley here as well.
Here is the arm and the socket for it. I welded the 3/4" strap down the length so it fit snuggly. I left the front bare, but ended up cutting it off because I broke a tap in a hole, and couldn't get it out.
here is where it is right now. I have labeled this picture so you can see what materials I used. Projects like these are built using what you have available. Don't think you need to use what I did.
Here is my first big oops. I welded the socket for the arm to the top of the angle iron. I forgot to square it with the shaft though, so it is 1/8" off. This will keep the belt from tracking straight with out over adjusting for it. I'll grind out the tack welds and re-set it.
Here it is from the back side. I was able to make the curved hole by drilling many holes close together then drilling out between them.
Here is the large wheel I plan to use on it. It is 11" diameter, and has a 2" face. It came with a 5/8" bore so I had it machined out at a friends machine shop to 3/4" so it will go on the shaft materials I have. I plan to cover it with leather.

Friday, April 14, 2006

I worked on the grinder a few nights this week. Last night Deb came out and helped as well. We ended up working on it till after 10 PM before we realized how late it was. The first thing I had to do was grind out the welds of the arm again. I didn't think I had it set just right, so I took the motor out and also switched the bearings to the inside of the angle iron they are connect to so that I could get a square against the shaft close enough to the arm to tell what was going on. I ended up putting the 11" wheel on the drive shaft just so I would have a good, square to the shaft, base to clamp my straight edge to. Once I did, I knew I was out still. I finally got it set straight, and actually welded it completely along both sides. I hope I got it right, because grinding that weld out will be a bear.

While I was fixing the square ness of it, I also made another slight change. I realized after tacking it yesterday that it probably wasn't a good idea to have put the angle iron base up the center of the tube arm. I wanted to be able to attach the upright along that edge as well, so I re-set it along one side. It will make sense in the pictures below I think.

After getting the tube where I wanted it, I started in on the platen. I kind of blew it by just eyeballing the cut out for the two guide wheels. Defiantly not my best work, but I think it will function ok. The platen is still 5 inches wide because I don't want to cut it down until I have the belts mounted and running. Once I get that going I will cut it down nicely, and I think it will look much better. I also need to get some better shim stock for the wheels to get them square before trying to run it.

This shows what it looks like now with the arm moved over and the platen done.
Here you can see the oops again, and how I used the level clamped to the wheel to make sure it was straight.
Here you can really see my OA cutting goof. Once I cut the platen down I will decide what to do with it. I may build up some weld bead on the edge to make it square with the wheels.
Here is the future upright sitting pretty much in place. I don't want to set it permanently until I get the drive and idler wheels, so I know it will work.
Here is another shot from the outside. Somewhere on that C channel will be a pivot with and arm that holds the tensioner pulley.
This is the basic layout of what I hope to end up with. It will be two grinders with one motor. One will have the platen, and the other the large wheel. That's Deb in the back talking to Pugsly, our dog.

Saturday, April 15, 2006

I got the tensioner built today, and put a belt on for the first time. I am still waiting for the drive pulley, and permanent tensioner, but the stuff I used for mock up is the same diameter, so it should be fine. It's actually starting to look like a belt grinder now.

Here are pics of it mocked up. The upright is tacked pretty good and once I get the permanent pulleys installed and ensure everything works, I will finish welding it up.
Here is a pic showing the angle of the belt at the back where it comes off the drive pulley. It's 55 degrees. I'm not sure if that is ok or not. I'll know next week.

Wednesday, April 19th, 2006

The grinder lives. I got it going tonight. I had to build a tracking mechanism to really make it work right. I had tried to do it without one, but the belt was running half way off the wheels, so I broke down and made the tension wheel pivot for tracking. It is still just tack welded mostly, so now I need to go through and weld everything up permanently. I also got the pillow blocks I needed for the big wheel on the other side, so I will start on that side tomorrow most likely. Then, next payday I'll order a second drive wheel and tension wheel from Rob Fink at Beaumont Metal Works. I am very impressed with the quality of the two wheels I got so far.

You can see how it is tracking off to the side. It worked, but not right. You can also see that the end of the arm is empty here.
Here is the nut I built into the end of the arm. A bolt goes through the tracking arm to act as a pivot.
Here is the tracking pivot clamped up to figure out the spacing. I figured out that I had to take off the two nuts that were on the left of the wheel.
Here are a couple pics of the tension device. You can see where I took out the nuts between the inside of the wheel and what it attaches to. I had to get it closer. I let it run for about 15 minutes tonight while I fooled around on a knife project on it. So far is seems to work well.
This will open in Windows Media Player most likely. It is an AVI file.

Thursday, April 20, 2006

I got the large wheel for the other side mounted tonight. I also found that there seems to be some kind of wobble back on the other side now. I took another video of it tonight, and it is pretty noticeable. I had to pound on the drive wheel pretty hard last night trying to get things lined up, and I am wondering if I might have bent the shaft somehow. I don't think I did, but I'll check it out tomorrow and see what the deal is.

You can see in the pictures below of the large wheel that there is quite a bit of extra shaft still sticking out. I was thinking about trying to add a buffer wheel on that end maybe. But, on the other hand, things are getting a little busy on this grinder, and that may be just a little too much. I'll decide later.

I'm still working on some of the details. I cut the excess metal off the right side of the platen so the belt runs along the edge now. I will cut out part of the left side as well so I have better access with my knives. I have decided to wire it up for 220v power because every time I start it all the lights dim for a couple seconds. So far it has worked very well. I have actually done a couple of little things with it, even though I have not finished welding it all up yet. It is very smooth running, and I think it is going to work just fine for a long time. I'll be ordering the parts I need for the other side on Friday, and should have the second side working next week.

Here is a close up of how I mounted the wheel. I may try to do something with that extra bit of shaft sticking out.
Here are a couple of shots of it. I still need to add the upright for the tensioner on the far side.
I also plan to build adjustable work rests for both sides.
Here is a shot of the mounting plate that I welded the arm to. I decided to cut out the hole so that I could weld around it on both sides. I will also add some type of brace to the angle iron, because I don't think it will be stiff enough without it.


Wednesday, April 26th, 2006

I did quite a bit of work on the grinder today. I rewired it for 220 and added a switch. Before I was just using the switch on a cheap power strip to turn it on & off. I can really tell the difference between the 120 and 220 power. The lights don't dim when I turn it on, and I couldn't slow down the wheel when I laid into it with some scrap. I could have pressed harder, but will wait till it is all welded up solid before I do any real heavy duty grinding on it.

I also cut out the excess metal to the left of the belt on the platen, and then also set up the big wheel on the right side to see if it works. It worked real well, and I have put some video of it running the big wheel up so you can see it. I think I may end up keeping it on the right side. I'll decide for sure once all the parts are here and I can run it both ways.

Here is the platen cut out. I cleaned it up more after this was taken. I'll put up a better pic tomorrow night.
Here is a wide shot of it with the platen cut out. It's also in its permanent home now on the bench next to my welder.
I moved the big wheel over to the right side just to check out and see if it works. I was very pleased with how smooth it runs.

Wednesday, May 10th, 2006

The second drive wheel and tension wheel arrived on Monday. I ordered more steel yesterday, and it was delivered today. I used a thicker steel for the tension arm on this side. I don't really like the thin wall tubing I used on the first side. Today I used 1 1/2" square with 3/16" walls. It is very stout. I did several things differently on this side. The first being that I boxed in the C channel at the top of the upright. Now the bolt that it pivots on goes through two holes about 1 1/2" apart. I think this gives it a little more support than the way it was done on the right. I also put the nuts into the ends of the arms much differently as well. This time I used two pieces of 1" angle iron as spacers, and then placed a 1/2" nut in the center and welded it all in. I think it is a much cleaner look, and it also was much faster that the first one. It also helped quite a bit that I was able to use the belt grinder to clean up the ends.

I have discovered a few things I want to change already. The way the big wheel is set up now there is about 19 inches between the two grinders. It is workable, but I plan to move the wheel to the outside of the upright after I buy a new piece of 3/4" drive shaft next payday. Once that is done it should have about 26" or so of space between the two belts. This will give me just enough more elbow room to help ensure I don't grind my elbow while working on one side or the other. For now I will just be real careful, or remove the second belt when I'm not actually needing to have both on there.

I have found that I like leaving a 24grit belt on the platen all the time. I use it for all kinds of deburing jobs and sharpening things. It is very fast and easy to use.

Here it is laid out. I tack welded two corners while it was laid out like this, then put it upright in the vise to get a nice clean weld on it.
Here it is after welding. Be sure to put the bolt in there so that the threads don't get gunked up with weld splatter.
Here it is with the bolt removed. I then took it over to the belt grinder to clean up.
This is how it cleaned up after about 3 minutes on the grinder. The whole process was much cleaner and easier than the way I did it last time.
Here it is straight on. There is about 19" between the two belts. I still need to build rests on each one. All 3 of these pics were taken while it was running.
Here it is closer from the left. I will eventually move the big wheel to the right left of the upright, and move the tension arm to the right.
Here is a good shot of both grinders. Once it is all done I will bolt it down to the table I think.

Tuesday, June 13th, 2006

No pictures tonight, just a quick update. I have been using the grinder for the last month. Wow, I really love this thing. Currently I have it all torn apart for welding and painting. I am also doing a few design modifications and little things to make it easier to use. I'll be posting more pics of it when it's all done.

Wednesday, June 14th, 2006

The grinder is really starting to come together. I decided that I want to add some actual blacksmithing elements to it to spiffy it up a little. I think it will look very sharp when it is all done. I painted the main body today, and welded a handle to the tension arm for the platen side of the grinder. I was just grabbing the bolt that sticks up as the adjuster and using it to pull the arm down to switch belts. Now, it has a cool handle made from a piece that I twisted up a couple years ago and never got around to using anywhere. I also made several double ended scrolls that I am welding onto some all thread rod to use as tracking adjusters.

Here is the main body hanging from my engine puller. I used the left over blue from the power hammer project.
Here is that handle. The two bars are 1/2" twisted then tapered to make it a little longer. The braid is made from 1/4" square, and it's actually all twisted, not actually braided.
Here it is after I mounted the tracking adjuster in front of it. I'm not sure what color I will paint it. The black is actually a primer. I'll probably use the purple from the power hammer as an accent on it.
Here is a closer shot of the wing nut. I used 1/4" round bar and just drew a taper out on each side, then rolled it up with scrolling tongs. The hardest part was making two the same size. I had to make 4 to get 2.

Saterday, June 17th, 2006

I did a lot of painting on small stuff yesterday, and was able to get the platten put back together today. I also spent a lot of time building a rest for the platten. Unfortunatly, I didn't really make any kind of plan, I just started putting stuff together off the seat of my pants, and so I ended up make quite a few mistakes. I've labeled them with the pictures.

Here is what I started with. I changed the bolts for the platten to longer ones so I could attach to them on the far side. I only had one bolt that was long enough and had threads the full length, so I used a piece of all thread rod for the back one.
I installed the two pieces and tack welded them together while on the machine so I could drill them and then weld bolts to the bottom piece.
Here it is ready for a belt. I realized after I was all done that the two nuts on the far end will totally be in the way when grinding knives.
Here it is open so I can install the belt. I'm going to have to completely rework it so that those two nuts are not blocking things.
Here is a shot of another little oops. I set the hole too close to the corner.
When I first started it up the tracking wasn't set right and the belt rolled around the side of the platten and jammed against the stop.
Can you believe I got it perfectly square actually? Too bad I have to pull it apart tomorrow and fix it.
You can see that the tracking is still off some. The belt tracks perfect on the platten, but is hanging off the drive wheel and tension wheel.
Another shot of it closer. You can see that the belt is hanging off the two pullys. I have to make some adjustments tomorrow.
Here is how the whole thing looks now. I did a little quick grinding with it tonight, and I like having the rest there. It makes it much easier to control

Sunday, June 18th, 2006

I was able to get the platten rest rebuilt today. I am pretty pleased with how it has turned out. Next step is to rebuild the other side with the large wheel. The good news is that this side is completly up and running now. I will paint the rest tomorrow night, and that will be the last of it I think.

I starteed with the bracket from the first rest. I had to cut the two bolts off first. I planned to use the old rest and just add to it.
Unfortunatly, I screwed up right off the bat by cutting all the way across where the black like is marked. I should hav just cut the top, then at a right angle as marked by the red line.
I ended up tossing the old one and starting from scratch. Then, I made a minor error on this one too. I marked the 45degree cuts on the top, but the point was at the far side, not where the cut would actually stop.
Because of that, when I bent the angle iron I had a 1/4" gap, which is the thickness of the material. I should have marked it on the bottom side.
Here is is from the bottom ready for welding. I welded the nut to the bottom side to give me threads for the wing bolt.
Here it is from the top again. Good thing for me ai am good at filling in weld gaps.
Here it is all done. You can see that I filled the gap and ground it flat. I welded a wing onto the top of a standard bolt to lock it in place.
Here it is straight on. It is very sturdy when tightened down. I'm not sure if I am going to cut off the tail on the left or not. I think I will leave it for a while.
Just a 3/4 turn of that wing bolt and it will open to let me change belts or do long stuff.

Wednesday, June 21st, 2006

I finally got the left side of the grinder pretty much done. It is back together and working now. I ran into several unforseen problems once I moved the tension arm to the outside of the upright. The biggest problem was the distance from the bearing that supported the shaft to the pully was now about eight inches. Even when I reduced the spring tension to the point where the belt was too loose to be useful it still bent the shaft when putting the belt on. I decided that I needed to get the bearing coser to the pully if it was ever going to work. I grabbed a piece of six inch C channel that I had grabbed at the scrap yard last trip. (It just looked like something I would need sometime) You can see in the pictures below where I added it onto the back corner, extending the width by about an inch and a half. I drilled it for the shaft to pass through and the bearing to bolt on, then tack welded it in place. It totally solved the problem.

Next step is making another handle like the one on the right side and some final paint. I've included another video clip of it running as well. Click here to see it.

You can see here where I welded the edge of the C channel to the edge of the plate the grinder is built on.
Here is a shot from the outside. You can see where I welded it at the top to the upright. I had to jump about a 1/4" gap with the weld.
Here is a good shot from the rear. You can see the blue upright where the bearing used to be. There was a lot of shaft just hanging out in space unsupported.
Here is the rest for the platten installed tonight as well.
I scratched it up some grinding a knife on it to try it out. I expect I'll probably end up sanding or wearing the paint off the top of the rest.
Here is a good shot of the whole thing. I also added a buffer wheel to the end of the other shaft. I'm not so sure about that, but will leave it for now.



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