Thread: Norton roughness, chips, edge shredding, micro chipping

Let's talk about the Norton embedded grit problem (aka Norton roughness, chips, edge shredding, microchipping, grit, grittiness, edge damage, etc)



Here's a copy of my email to Norton:

This is regarding a new Norton 4000/8000 waterstone... which I was advised is currently the benchmark in waterstones. The stone gets embedded with coarse grit from lapping (or the stone contains a coarse grit). The grit is far coarser than 4000 or 8000 and causes severe damage when using the stone. The embedded grit is not completely removable. I have spent m-a-n-y hours thoroughly, systematically and methodically eliminating other potential causes... it is unequivocally and without question the Norton stone. This stone has cost me many hours in restoring damage that it has caused (i.e.: chipping to precision edges, as viewed under a microscope). A replacement would be appreciated as I've heard that the symptom I'm experiencing is not an isolated incident. Thanks for your help.



Here are some historical threads on SRP regarding the Norton problem:

"Norton Roughness" by rustyblade
http://straightrazorpalace.com/showt...rton+roughness

"Pitted Norton 4000 water stone" by Oo.Mark.oO
http://straightrazorpalace.com/showt...ghlight=pitted

"Pockmarked Norton 4000" by smythe
http://straightrazorpalace.com/showthread.php?t=16072

"'feel' of the Norton 8k" by Bruno
http://straightrazorpalace.com/showt...shredding+edge

"Norton's shredding my edge" by JoshEarl
http://straightrazorpalace.com/showt...shredding+edge

"My Norton saga continues" by JoshEarl
http://straightrazorpalace.com/showt...highlight=pits

"Norton 8000... has this happened to any of you guys?" by coully
http://straightrazorpalace.com/showthread.php?t=6843



Some techniques I've used to eliminate the Norton as cause of the embedded grit symptom: L-o-t-s of water, 3m sandpaper, Norton sandpaper, 320 grit, 400 grit, 600 grit, 1500 grit, changing sandpaper frequently, light pressure, no pressure, lapping figure 8s, lapping circles, scotchbrite scrubbing, finger rubbing (until bleeding I might add), more rinsing with lots of water, frequent microscoping of edge when honing, grit picking, clearing stone of grit with backhoning, lapping with Kitayama, reading just about every post on SRP regarding this problem, watching Lynn's dvd repeatedly, using the Kitayama as the comparison stone throughout testing (as a 'control'), and last but not least... this post.

I have not used the Norton lapping stone - but the fact that the Kitayama tolerates sandpaper lapping without issue suggests the Norton should too.

I will post as Norton replies... until (or if) this is resolved I'll backhone with 1500 wet sandpaper on a marble tile and then final hone on a 12k Kitayama waterstone (which works quite well).

I wonder what true percentage of the Norton stones demonstrate this symptom... either way - please vote on this poll.

The main problem I has was little tiny bits of grit in the 4k sides (and very occasionnaly onthe 8k side) - all of this was remedies by rubbing the stone with my hand under water after I finished lapping it.

Mark

I don't know if this has ever been talked about- and it's just an idea mind you- but maybe sandpaper should NOT be used to lap a synthetic stone such as the Nortons? I use a DMT and have not had any problems whatsoever. Even particals from honing have not harmed my work. The stone definitely gets colored, even after rinsing, but I still haven't had problems. I'm guessing Norton would not recommend sandpaper, but that could just be to push their own product. Just a thought!

I use the Norton lapping stone...so???

Mark

Mark (Milton Man),

Am I to understand that you have experienced the Norton embedded grit problem from using a Norton lapping stone?

Precisely - it somehow left either small grit or just very rough. Either way, rubbing the palm of my hand over the stone under running water eliminated the problem all together.

Mark

I have a Norton 220/1k, 4k/8k and the Norton Lapping stone.. I guess I'm just lucky, but I have had absolutly no problems with grit, after lapping, I just wipe the stones with my hand, under running water, and BAM on to honing... Like Lynn I lap every session but I definatly do not have as many sessions as he does I average 5 razors between lapping, and maybe I'm wearing out the stone early, I don't know only time will tell.....