Polishing D-2 Tool Steel Rollers? 2

[Vindicit]

I have some sheet metal rollers that are D-2 and hardened. These rollers are probably at least 20 years old and are in need of some maintenance. They are pitted and have scratches. What would you guys recommend for polishing hardened rollers? Would I have to get some kind of compound or would 400 grit sand paper and some lubricating oil while finishing it with some scotch brite work out?

 

[EdStainless]

If you need to remove the pits then they need to be turned or ground first.
If you just need to clean them I would start with 320g wet and work to finer as you get it cleaned up.

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P.E. Metallurgy, Plymouth Tube

 

[tbuelna]

I would have them re-ground to completely remove the pitting/scratches. First, re-grind the roller with the worst pitting to 100% clean-up, and then grind the other rollers to the same size. Simple OD grinding is not that expensive, and it will give a much better result than hand sanding. Spending 200 bucks or so every 20 years to keep these rollers in good shape seems fairly reasonable.

 

[Vindicit]

These rollers are precisely shaped rollers and removing even a few thousands can change the dimensions of the part that it forms so I don't know if I should go through with grinding/turning it. I can put the roller on a lathe to spin it and assist with the hand sanding.

 

[Tmoose]

How hard? Would a new file put a tiny flat on a corner/edge?

 

[Vindicit]

The hardness is probably on the softer side maybe low 50s HRC. Im just concerned with changing the shape by turning the roller with anything hard like a file or cutter.

 

[SwinnyGG]

If the shape of the rollers is that critical, you should be running away from hand finishing, not towards it.

'Machining' via sandpaper using your hands will not result in consistent final dimensions. Turning and machine polishing will.

 

[Vindicit]

I would think that with sand paper that taking off a few thousands of material is quite difficult if using a higher grit while using a file or cutter you could accidentally take off a chunk of material easily if you're not paying attention.

 

[EdStainless]

But with sandpaper you cannot apply even pressure and you will change the contours.
Pay to have them ground properly, like they were made in the first place.

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P.E. Metallurgy, Plymouth Tube

 

[Vindicit]

Ok Ill look into doing that. thanks

 

[sreid]

3M Diamond Lapping Film?

http://solutions.3m.com.hk/wps/port...rvices/products/abrasives/DiamondLappingFilm/

 

[John2025]

If you're going to sand them , I'd hit them with a fine file or a stone to take of the high spots that form beside nicks and dents first. In fact, I'd probably stop after taking off the high spots.

 

[Tmoose]

Yeah, using abrasive paper doesn't really remove the material raised adjacent to a dent/or divot. I just end up with in smoothly finished, possibly even shiny bump.