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Jerschmidt 2×72″ Belt Grinder (Completed)

Hands down, Jeremy Schmidt’s belt grinder is the best DIY belt grinder I have seen available on the Net.  His plans are well written and easy to follow and the finished product is rock solid (check out the washer vibration test below).

Jeremy Schmidt’s DIY videos are both entertaining and informative.  I had never welded before seeing Jeremy’s table saw fence with incremental positioning but it seemed reasonable for a first welding project. Let’s just say Jeremy made it look easier than it actually was but in the end, I was able to make my own.  Check out his 2×72″ belt grinder build.

Belt Grinder Washer Vibration Test

I tried to calculate how much raw material would be needed for this new build. This is around 55 kg (121 lbs) of steel.
The first modification to the original design was to use four (1cm x 5cm x 41cm) steel flat bars for the base frame. Having them extend over the edge of the solid square bar on all four sides allows the frame to come out square.
A close-up view. Notice there isn't a whole lot of real estate for welding the flat bars together.
For this reason, I built a simple jig to allow me to create a 45-degree chamfer on two opposing edges of each of the four flat bar.  This way I will get 4 nice v-grooves along the length of the frame for welding the tube together.
I simply ground the chamfer by placing the flat bar on the jig and moving it back and forth along the belt, making sure to apply pressure evenly.
Now there is a nice v-groove for the weld bead.
Using box cutter blades on all four sides gives a .030" space between the mounting bar and the base frame. The tricky part was getting the blades to stay in the center of the bar (on all four sides) while clamping. To achieve this, I placed the shims on the top and bottom of the frame first, then I clamped them in place.  I then rotated the frame (as pictured here) and added the shims to the two other sides, then clamped those in place. THIS IS VERY IMPORTANT, if you want your frame square and true.
The slight gap formed by the shims should be even on all sides.
I took my time to clamp the frame. The whole thing will need to be rotated in order to tack weld it together.
I removed the clamps while the frame tube was still warm because it's easier to knock the frame off the square bar.
Knocking the tube off against the edge of the bench-top was fairly easy, even with one hand.
Still square!
The solid square bar should be true to the tabletop also.
Shortening the square bar for the tilting frame.
Today I welded the two frames (but my phone died and I couldn't photograph the progress). Here is the base frame after welding and grinding flat. I hate grinding!!!
I used 5 discs in total to clean up the two frames...
and got dust everywhere.
I do like how they came out though.
Before moving on with the build, I decided to clean up the frames (otherwise I wouldn't do it later).
Before...
and after.
Scrubbing pads, before and after.
The two frames alone weigh 11.6 kg (25.5 lbs)... the goal is to keep the whole thing under 45 kg (but I have my doubts).
This afternoon I squared up the ends of the frames.
I haven't quite finished modifying my metal miter saw but I thought I would use it to get straighter cuts...
Instead of using aluminum oxide grain wheels (the same thing as those messy grinding wheels), I'm using an Irwin 14in, 80T circular saw blade.
I made the feet a little taller than in Jeremy's plans.
The cuts were slightly off... however, that can be fixed with a "belt grinder" 😉
I've attached a perpendicular guide to the grinder table in order to grind parts at 90 degrees.
That's more like it. The 1" x 2" x 3" Precision Steel Blocks are a must!
I did the same for the steel bars that will make up the base of the feet.
Chalking up the steel plate for placement of the feet.
I tightly secured the feet to the tabletop in preparation for welding.
OK, now this is my 5th welding project so I'm not sure if this is a "proper" bead...
but it is my best bead so far (hey, I'm still learning, Youtube style).
Hurray, it's level.
Yeah, I know, overkill!
I need to figure out how I'm going to weld the frame to the feet.
If I flip it upside down and placed the feet on the frame, I wouldn't know if it were level until I flipped it back around (due to the outside faces of the frame not being perfectly straight).
So here's an idea...
What's important is that the square bars (inside the frames) which the grinder table and platen attachments are attached to are level, square, true, parallel, etc. Therefore by clamping a Fireball Tool Monster Mini Square to the square bar and tabletop, it insures that the frame is in the correct position for tack welding from underneath.
A close up to give a better idea of the idea.
Here is the end of the frame, the square bar is also parallel and perpendicular to the tabletop (as it should be). 
I'm taking a break from this build to make my DIY electromagnet drill press table. BBS...
Well, here it is... my DIY electromagnet drill press station.
Ready to start drilling!
I cut out a jig template, using the CNC, for the 5cm pieces. The pieces fit tightly in the slot and absolutely no movement while drilling (and no need for clamps).
I'm drilling holes into the frame (call me paranoid) in order to fill them up with weld (to strengthen the joints).
With the 1cm template in place, I was able to drill the holes exactly 1cm from the edge.
 
It came out better than before (ok, paranoia is gone).
Before welding the frame to the feet, I needed to tap a hole in the side.
8mm tap.
This will become the knob that tightens the table attachment.
This would have been a HUGE MISTAKE... I almost welded the frame the wrong way. The tapped hole needs to be on the other side.
It was difficult to tack weld the feet from underneath, there wasn't enough clearance so I couldn't get the arc in the right place. In any case, I was able to tack weld it enough to flip it over and finish the job.
I made this simple jig to raise the tilting frame 94mm from the tabletop and about 14mm from the other frame (i.e. the correct location for the hinges).
The space between the two square bars is the same in the front...
as in the back (let's see what happens after welding the hinges).
Hinges go on next...
I couldn't take the angle grinder dust anymore... I went out and picked up this mini metal band saw.
It cuts amazingly straight and NO DUST getting everywhere!
What is wrong with this picture?
Don't do what I just did! The gap between the table and the belt should have been narrower than the thickness of the piece I was grinding. I thought I would quickly clean up the pieces and I ended up grinding off about a third of my thumbnail. The belt grabbed the piece so quick in a downward motion and pitched my thumb up against the grinder before I knew what happened. It didn't really hurt at the time but I'm not planning on doing that again.
Notice the space now, I should have known better.
The bottom of these 3 hinges needs to be straight across and perpendicular. The top isn't that critical as they will be shaped using the radius jig.
I'm using the 1.25" template to drill an 8mm hole in the same location of all three hinge pieces. After shaping them with the radius attachment, I will then re-drill them with a 12mm bit.
I still need to make the pegs that secure the pieces to the radius jig... but in the meantime, an 8mm dowel works just fine (this is the reason for not drilling them 12mm at first).
I had to put on some gloves, these little pieces get HOT!!!
Finished with half the hinges... tomorrow I will start the other (more difficult) half.
Go figure! My new mini band saw was too small to cut these pieces. Back to the angle grinder 🙁
(BTW, that photo was taken blind and with one hand)
 
I had to use a hack saw to complete the cut.
One down, two to go. Same process.
Out of the whole build, this guy requires the most time.
A lot of the work had to be done with a hack saw.
Next step is to finish these with 120 grit on the belt grinder.
Sweeeeeeeeeet!... Now you know why I say. "You really do need a belt grinder to make a belt grinder!"
I didn't have time today to complete the other two parts of the left hinge.
This photo got me thinking... can a belt grinder be made out of stainless steel? You gotta love that look!
Since the motor is 6000 miles away, I made this template to help with the correct placement.
I didn't realize what a beast it is; it's huge!
The radius jig is amazing.
This piece took the longest time to make. Soooooo much filing. There has to be an easier way!
7 out of 8 pieces came out good... one was too short.
I will have to redo this piece.
This simple jig places the hinges in the center of the tilting frame? The tilting frame is 40mm across. The bar going through all the hinges is 12mm in diameter. The piece of wood is 14 mm thick. So by placing the bar against the piece of wood it insures the hinges are centered.
Frames are done. Moving on to the motor mount.
I'm using a simple jig (i.e. 5 pieces of wood) to help place the motor mount in the correct location and position.
By placing 2 pieces of wood under the tilting frame (exactly the same height from the table top to the bottom of the tilting frame) and 1 piece slightly taller, I will be able to weld the motor mount a lot easier (and perpendicular to the frame).
By placing the end piece on the taller jig piece, I can clamp it tightly to the end of the titling frame. It is equally spaced between the top and bottom of the titling frame and parallel to the table top. I placed the lower bracket support on the 2 piece of wood that run under the tilting frame.
On the lower bracket support, I placed another two pieces of wood (3.5 cm wide) on which the top bracket support will sit.
Now I'm ready to tack weld.
 
Making sure it can tilt.
Welded solid on top, side and bottom to make sure it can hold that big motor.
I drilled 7mm holes in the motor mounting plate in order to tap 8mm holes.
SHOP TIP: I find it a lot easier to use the drill press to get the beginning of the tap started. Taps are always perpendicular and straight. I ended up just turning the bit by hand (instead of with the pliers). You don't need to tap the hole all the way through (too difficult). The point is to get the threads started and then finish them with the tapping tool.
Since I don't have the motor with me, I made this template to help with its placement.
With the template centered across the top of the tilting frame, I can now weld it in place.
I will need to make a 21cm high stand in order for the grinder to rotate properly.
Welded and cleaned up.
Next is the tensioner post...
When drilling larger holes I normally start with a smaller drill bit (about half the actual hole size) but here I drilled the 12mm hole in one go.
Here I deviated from Jeremy's plan with regards to the motor mount. I made it a little bit wider so that I could weld the tensioner post to the front edge of the motor mount. The reason being twofold; ascetics and strength.
Time to move on to the tensioner.
I tacked welded (then grinded off) the tensioner three times before getting it in the right position...
the bolt that hinges the tensioner glides in like butter. 🙂
The tortion spring was made out of 1/4" piano wire (with 6 coils)... perfect tension!
Tensioner was completed today.
Close up view.
Here's yet another jig, this one is for making the platen attachment...
I deviated from Jeremy's plans slightly as far as the look of the pieces. It will become more apparent when I mount it to the steel tube.
Welding the pieces together was pretty straightforward and simple. Note: I had to make sure the 1-2-3 block was touching at least one of the pieces when I was welding (since the jig is non-conductive).
Another modification is that I made the platen attachment fixed to the steel tube.
The platen will sit on this brick.
 
I will need to position the platen attachment in the correct location using clamps, mini monster square and the 1-2-3 blocks.
 
Need to make sure it sits true.  Very important for the belt to track correctly.
Once I was comfortable with the position, I started welding in place.
Tapping the 1/2 holes...
again I use my drill press to get the tap started.  This insures the thread are started at 90 degrees (and are straight).
Then I finish by hand.
Now on to the table attachment 🙂
Well today I got back on the build, after 11 days, but my MIG welder is acting funny.  Sounds a bit different and bead wasn't "flowing".  I ended up grinding this down and redid it.
I'm so glad I bought this mini metal band saw, I use it more than I expected I would.
Can some experienced welder tell me what's wrong with this weld.  The MIG is still "spitting" the bead out.
 
 
 
 
 
 
 
 
 

Equipment/Materials/Tools Used in Project:

I’m surprised how many people inquired about the JerSchmidt decals I put on my belt grinder.  Click on this link to download the PDF: JerSchmidt_Decals.pdf (837 downloads)

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Steve A.

Thanks for sharing. I like the video and the progress of your build but if you already have one, why are you building another one? I was just curious.

MadeinAmman

Thanks Steve. I normally wouldn’t since I still need to finish setting up my shop but its for someone else.

B.B.

I love your photos. I feel I’m there to watch the progress. Keep it up.

MadeinAmman

Thanks for the comment B.B.