2018 Grinder Build

[bjansen]

I spent some time putting together a grinder build along.  I have built 9 grinders over the past 5 years and I have revised my plans a bit each time – I think I now have what I think is the perfect grinder.  I put together this build along so that others who may want a nice grinder could see that they can be built fairly easily with tools you likely already have. All in, anyone with a drill press, sander and some hand tools can build a top of the line variable speed 2x72” grinder for about $1,000 and a person can build one much cheaper if some of the metal/parts/motor, etc. are already in the garage.  I also drew up plans and a detailed parts list for this grinder – I am happy to share them and I can email them to you if you drop me a PM. 

Starting with the raw materials cut to size.  You can buy the items cut to rough size, or cut it yourself.


Cleaning up all the edges – I used my mill with a roughing end mill to do this, but you do not need a big mill to accomplish this step. 

You can use files, a random orbital sander or belt sander to get this done.  Take your time on this part to have a nice finished product.  Pictured below is the first belt grinder I made – I made this grinder entirely with woodworking tools and a drill press. I cleaned up and polished all the edges with a combination of files and a random orbital sander, followed by a buffer. It turned out very well – just took a bit more time.   


Time to start the build – first starting with the tracking assembly.  You will see many of the steps to follow are simply marking a hole, drilling a hole, using the drilled hole to mark another hole and tapping the second hole, then repeat.  Take one at a time and your build will be precise. 





You may need to countersink the material a bit to allow for the shoulder bolt to have proper depth in your tracking pivot piece.  Shown below is what I did.



Once your tracking assembly is bolted together, then mount it to the tracking arm.  Here I drilled all 4 holes and then transferred those to the tracking assembly.

[bjansen]

One hole and bolt at a time will guarantee a good fit up. As I mentioned, most of this grinder build is simply transferring holes, drilling & tapping…then repeat. 

Tapping the ½-13 hole for the tracking wheel bolt and then transferring that to the tracking arm to determine the exact location to drill for the 5/16” tracking adjustment screw. I will drill/tap the arm for a 5/16” threaded steel insert.



Mounting the handle

The completed arm unit

On to the arm mounting uprights.  Drill, tap and countersink for the 3/8” shoulder bolt.  Then cut your spacers to length, with .125 worth of washers and a 1” wide tracking arm – I cut my spacers to 1.125


On to the body – mark and drill your holes for the left side.  Notice, I also drilled and tapped the left side for threaded steel inserts for my tooling arm locking handles.

Then transfer those holes to the right side (one by one….or at least one by one until you get 3 or 4 holes, then you can knock the rest out all together)

Next is the hard part – or at least a time consuming part depending on what kind of tools you have.  You will need to make clearance for the face of the motor that extends beyond the c face.  This is not much material to take off and can be easily done with a mill.  If you do not have a mill, there are a couple options:
1.    You can use your drill press – just mark out all the material you need to remove, drill and then use a chisel to bust out the webbing. 
2.    You can use a 4.5” hole saw and just drill the whole 4.5” section out.  The diameter of this inset portion on a 56c and 145TC face are  4.5”
You could also probably just skip this step and bolt the motor up as is – you would only lose a couple hundred thousands of shaft length on the other side of the plate by not removing this material for a flush face mount.  The ring on most of the motors I have seen is flat and would mate just fine with a flat surface. 

[bjansen]

On to drilling the spacers.  I start with the top, line it up with the left side plate, mark the hole and drill it.  If you drill these holes one at a time, you will be successful and it will be a clean assembly.  After you mark and drill the first hole put the spacer back in place, use a screw to locate the first hole and then mark and drill the second hole……then reassemble put screws in both holes and then mark and drill hole no. 3. 


I will then put 2 pieces of tape on both sides of a 1.5” tooling arm and use that as a proper spacer when I mark the next piece.





Here is a tip:   when you are drilling your spacers, mark them on the top to identify the top and the order they go on. 

Next, lets mount the base. Drill some perimeter holes to bolt the unit down to a bench, then lets work on mounting the base to the unit.  I keep the base flush with the front and about 2 -2.5” of overhang on the belt side.  I use 4 screws to mount this.  I simply mark some rough locations for 4 holes, then mark the first (drill and tap), then repeat until I have all 4.







Now final assembly.  Use threadlock.  Notice the .020 spacers between the left side and the tooling arm spacers.


 
Sand the motor shaft and use this stuff to be able to get the drive wheel off in the future, if needed.

I usually mount the gas strut and the brackets once it is all together. Aim to keep the tracking arm just above level when the spring is fully extended – under load, with belt tension we are aiming for a level tracking arm which will provide the best tracking.   






Here are a few other examples of the finished project. 

[KSCATTRAPR]

Thats pretty sweet, thanks for taking the time to share all the info and pics!

[COknuckledragger]

Nice build! Thanks for your effort in documenting it! I've bookmarked the page for ideas for a future build! 😃

[Benjy]

Brad, I sent you a PM, I think!!!! I am interested in your plans, especially the motor and speed controller...

Thanks,
Benjy

[Bill Kissner]

Brad, your skills are unbelievable! Good job buddy!

[Cyclic-Rivers]

Brad, I envy your skill set.

[Devon]

Many thanks for the plans!  This was a fun build for sure.  It is a great grinder and will sharpen a mower blade in a blink of an eye.   If I can do it, anyone can.

[bjansen]

Nice clean build !!

[Benjy]

Wow, Very Nice! Great Job!