24" X 1" Belt Grinder

Made small 24" x 1" belt grinder for my little workshop.

https://www.youtube.com/watch?v=UxfG2OZYlr8

As my workshop is only 3 x 2 meters (6 square meters) and already have lathe, milling/drilling machine, 2 benches, etc inside, there is no much room left for big machines. Actually I don't need 72" x 2" belt grinder at all. This small one is all I need.

Materials used:
mild steel, 304 and 316 st. steel, 6061 aluminum, angle grinder.

Unfortunately cordless grinder died. The only 2 good things about this cordless grinder were: 1. cordless, which is good as you don't need extension cables when moving it out of workshop and 2. several speeds for various materials and various grits belts. All the rest wasn't so good. No enough power for this task to start with, spindle lock button, etc... Lidl brand Parkside came with 3 years warranty, so I returned it to them.

Either drive wheel or tracking wheel must be crowned (barrel shaped), not the contact wheels. As drive wheel is perfectly fabricated and well balanced, I crowned tracking wheel. This is the blue one, which I ordered from aliexpress. They call it chain roller tensioner. I bought 3 of them as they were very cheap and I was too lazy to make them.
Later I just replaced them with ball bearings (62200 - 2RS1, 10 x 30 x 14 mm)

3 drawings attached and the rest can be seen in the video clip.

Cheers
LMMasterMariner

Thanks for the video and drawings! Good craftsmanship again!
One of these days I'll get myself together and wing something of the like together,
that'll give me some use of a mixed full bag of 533 x 75 (21 x 3") belts of different grades...
Guess I'll be so cheap as to cut them along the centre for a 1,5" wide belt in a smallish DIY grinder.

Tip for a pretty good load of very different kinds of royalty-free music: https://freemusicarchive.org/
Perhaps you'll find something to your liking that'll complement your excellent videos!

Cheers,
Johan

PS: This is a given tune for, say a 4 min disassembly/ assembly time-lapse?:
https://freemusicarchive.org/music/B..._Zeppelin_1908

Thanks for royalty free music tips. I used one from my previous posts (acoustic blues). I am currently uploading new post (24" x 1" Belt Grinder). Once uploaded will delete this one (24" x 1" Belt Sander). I am also cheap. I am cutting 610 x 75mm belts in 3 pieces. 533 would be little bit too small, I think. I wanted to have at least 100 mm platen. It will be shorter with 533mm belts.

New video posted. Hope you like the music.

Cheers
LMMasterMariner

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Thanks LMMasterMariner! We've added your Belt Grinder to our Grinding category,
as well as to your builder page: LMMasterMariner's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="https://www.homemadetools.net/homemade-belt-grinder-130"> <img src="/uploads/249211/homemade-belt-grinder-130.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="https://www.homemadetools.net/homemade-belt-grinder-130">Belt Grinder</a> <span> by <a href="https://www.homemadetools.net/builder/LMMasterMariner">LMMasterMariner</a></span> </div> <div class="tags">tags: <a href='https://www.homemadetools.net/tag/belt-grinder'>belt grinder</a> </div> </div> </div> </div>
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It is also possible to install contact wheel 112mm dia. 2 new drawings are here.


Cheers
LMMasterMariner

LMMasterMariner,
Very nice work on your 24”x1” belt grinder.

Thanks for the Mk II 112mm wheel upgrade, LMMasterMariner.

-Do you change the crowned wheel (I guess it originally sits right above the platen?) over to the tensioner arm as well?
If so, how do you adjust the belt tracking?

Just curious

Johan

Quote:

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Originally Posted by DIYSwede

Thanks for the Mk II 112mm wheel upgrade, LMMasterMariner.

-Do you change the crowned wheel (I guess it originally sits right above the platen?) over to the tensioner arm as well?
If so, how do you adjust the belt tracking?

Just curious

Johan

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I didn't remove tracking wheel. it's the blue one on the tension arm, so tracking should be good.
And there is no need to remove upper contact wheel (top left) and spark arrestor. They are not in the way of the belt.

Cheers
LMMasterMariner

Thanks for clarifying!
From my (too) quick glance at the drawings I thought the crowned wheel was on the top front position,
now I realize I was wrong, again! :)

I guess shoulda gone through your eminent drawings more carefully - not jumping to conclusions... Ah, well.

ATB
Johan

Quote:

---

Originally Posted by DIYSwede

Thanks for clarifying!
From my (too) quick glance at the drawings I thought the crowned wheel was on the top front position,
now I realize I was wrong, again! :)

I guess shoulda gone through your eminent drawings more carefully - not jumping to conclusions... Ah, well.

ATB
Johan

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Thanks for the word 'eminent' when describing my drawings, which are all made by MS Paint. PhotoFiltre is used to rotate parts and gears are designed with GearDXF. Never had patience to start learning and using any CAD program.

Cheers
LMMasterMariner

Quick question: -Anybody having problems overrevving ball bearings?

For instance, given the 12 000 rpm angle grinder and a 60 mm OD drive wheel,
the suggested 62200 2RS1 (with 17000 max rpm) would get up to 24 k rpm...

(A 43 mm OD drive wheel would keep the revs down, but still provide 60 mph belt speed)

Any risk and/ or damage assessments out there?

Just asking, and better safe than sorry...

Johan

Several years ago I had a high rpm air powered hand grinder. I had two of these totally blow apart where the ball bearings simply disintegrate. Pieces flew everywhere. I think it hade something to do with not having dry air. I should have had a better air lube system as well.

OTOH: Given the 17000 max rpm of a 10 mm OD inner axle,
would perhaps allow the 30 mm outer race a max (theoretical) rpm of 25 500 rpm
(given an assumed ball cage max rpm of 8500 rpm)?

https://en.wikipedia.org/wiki/DN_Factor

I still remember my engineering teacher in 1977 dissing rotating outer races rather than inner axles.
BAD engineering practice...

Or, am I mistaken (again)?

Johan

Unless I am mistaken, I would think the outer race would rotate at would rotate at a slower speed than the inner race. But I am not an engineer.
I am still interested in what you find. Maybe the manufacturer could shed some light on this.

Quote:

---

Originally Posted by DIYSwede

Quick question: -Anybody having problems overrevving ball bearings?

For instance, given the 12 000 rpm angle grinder and a 60 mm OD drive wheel,
the suggested 62200 2RS1 (with 17000 max rpm) would get up to 24 k rpm...

(A 43 mm OD drive wheel would keep the revs down, but still provide 60 mph belt speed)

Any risk and/ or damage assessments out there?

Just asking, and better safe than sorry...

Johan

---

Yes. You are right. Thanks for pointing this out.
It's better to put 3 bearings 6200 2Z (limiting speed 24000 rpm) than 2 bearings 62200 2RS1.
When I was ordering bearings, I ordered 6 pcs 62200 2 RS1 and 9 pcs 6200 2Z, but decided to keep these 6200 2Z for some other projects.
Will replace them once I come back home.

Cheers LMMasterMariner

No big deal - I was just bothering my brain with this.

Hypothesis: When an axle in an inner race rotate @ 17000 rpm,
hence the cage should rotate with half that rpm (as the outer race is fixed) 8500 rpm, Right?
This is where I was mistaken:
In wrongly assuming the outer race could turn faster than twice the given ball cage max speed.

Thanks for pitching in, you guys!
Johan

PS:"Nobody can fool me as effectively and easily as I can"

Quote:

---

Originally Posted by DIYSwede

...PS:"Nobody can fool me as effectively and easily as I can"

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The first principle is that you must not fool yourself - and you are the easiest person to fool. - Richard Feynman

You're in good company. It's a darn hard thing to learn. DAMHIKT.