# Why and why not? Grinding/ polishing questions.



## toek (Dec 13, 2013)

Why are most beltgrinders for knife making 2" and not more? is it for monetary reasons or just that there are more belts in that dimension or is it for some technical reason? 
Why not use a oscillating discsander or deltasander with wet/dry papers in progressive grits like from 120 - 4000 for surface polishing the blades?


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## Delbert Ealy (Dec 13, 2013)

I have used wider belts and it seems to make it harder and not easier to grind blades of any size. Also with 2 inch you know that you are going to make full use of the abrasive, with wider belts on smaller blades you might wind up with some unused abrasive in the middle of the belt.
Changing belts is quick and easy, which is not always the case with discs. Cleanup goes much faster with belts even if you discount the time it takes to change discs.
It is certainly possible to use other than the standard tools to make knives, but for someone like me, doing this for a living I need to have efficiency in every place I can. 
I have made knives with just a file and some sandpaper as well, it's not as bad as you might think, but it's still faster with a belt sander.
Del


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## toek (Dec 13, 2013)

Beltgrinder question totaly satisfied with that answer makes sense.
Regarding the question about polishing with discsander, its often adviced to use sandpaper and micro mesh to polish by hand after thinning etc. If you were to use a discsander for that instead im thinking time saver and also less prone to leave scratches as it oscillates? Im thinking of a 5" handheld discsander the once all of us have in the garage :wink:


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## NO ChoP! (Dec 13, 2013)

I like a unidirectional scratch pattern. Even at higher grits, sanding leaves micro scratches. I would think an oscillating disc would leave a very random pattern.

I also like to use wet dry/ cloth backed paper when hand finishing, and use a little water. It seems to really help brighten the polish.

I have recently found using the slack on a simple belt grinder with cork or scothbright belts is super easy and effective. A HF 1x30 can be had for the same price as most orbital hand sanders.


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## Twistington (Dec 13, 2013)

Random orbital sanders leave a very messy surface on steel, alot of ridges that can bounce the light from all directions. Unidirection makes for a much better result, spray some wd40 or similar on the steel and sand until you have the surface at the finish you want. Tormek has a stropping paste that you can combine with the higher grit papers for pretty neat results.

Mirka sells some 5mm thick sanding pads that are nice aswell, they last really long...


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