Need some advice ASAP!

Just a shot in the dark here, but is that on both sides of the blade or just one?? Couldnt tell from your photobucket...
 
I have seen this affect to some extent happen when you clean a blade with certain chemicals like hydrochloric acide and it is not fully rinsed before going into temper. Even water can do this to a blade to some extent if you put a wet blade into a hot kiln for temper. I am not for sure that this is what happened thow.
 
This was likely a piece of 1095 HTed like it was stainless steel... Way to hot and was air quenched
 
The spots are on both sides of the blade but not on the tang. The Buck guy said that the knife was too long for the container that he quenched it in, so the tang wasn't hardened all the way. I decided to go ahead and sand it all off. I am a little scarred to etch it. I think I'm going to just polish it and call it good, unless you guys think that the etch would be worth the risk. I would try it if the knife was for me but since I'm making it for somebody I'm a little hesitant to experiment.
Is there a special technique or something to get the scratches out from the courser grits? Even after sanding for hours my blades are always still full of scratches. I have been hand sanding because I don't know what else to do. The highest grit that I have for my belt sander is 120.

Here are some pics of where I have it at now:


 
Hankins is spot on with the overheating from being treated like stainless theory. With a simple hypereutechtiod like 1095, especially if it is 1095 from Admiral which typically has visible carbon precipitation banding, but to a lesser extent any simple hypereutechtoid without carbide formers like Chromium to bind with the precipitated leftover carbon, if you overheat it the carbon aggregates and you end up with little high concentration zones with 3-5 percent carbon which effectively make little areas of cast iron which liquify at much lower temperature than the steel and run out. That would explain the wet puddle effect on your surface if it was treated in an inert atmosphere oven so the little cast iron puddles didn't turn into little fountains of sparks

-Page
 
I think in order to get those "scratches" or bubbles off the blade, you'll need to go back and use your belt sander at a course grit then work back up to hand sanding. This (the close up picture in your post above) reminds me of when I clay harden a blade and how it looks after scraping the clay off then tempering right away. The blade almost has a topography from the oil spots from the quench that seems to cook onto the blade when in the oven tempering, becoming harder to get off, at least mb hand sanding.

I used to hand sand the blade in this bubbly state in the past starting with a cut off from a fresh 36 grit zirconia belt, and would end up taking days trying to sand it so that it looks decent, I was ignorant lol... well I was more scared of ruining my grind lines using a belt sander after HT. Now, I do go back to the grinder after HT-ing making sure of course to make sure the blade stays cool by dunking in water between each pass. I'll go to bout 400 grit then proceed onto hand sanding. Anyway that's just my 2 cents and all I can think of adding :)

That's a greating looking knife man, I like that profile for a chefs knife! good luck :)

Paul
 
Page, I think, you and Robert are spot on. Maybe someone forgot to change the setting on their furn And then it may be in the Admiral part of it.
Thurm if you have any more of this bar of steel, make a small necker and send it to Peters and see how it comes out.
Just my 1 cent [ I'm retired on ss, don't have 2 cents] Jerry
 
Patience is the only key to getting the scratches out. There are plenty of tutorials on Blafeforums with the proper technique. The only thing to remember is to remove all the scratches from the previous grit before moving to the next finer grit. If I were you I would start at about 120 tang to tip changing the paper when you feel the friction start to lessen. DO NOT GO TO A HIGHER GRIT UNTIL ALL SCRATCHES ARE CONSISTENT. (check out Nick Wheeler's video in the video section) Verify this at all angles and in all kinds of good lighting. Use a loop if you have one. On the next grit change the sanding direction by 45 degrees so that you can differentiate the scratches from that grit with the previous. Keep going like the previous steps until you finish with thte grit you want. I like 600 tang to tip (not back and forth). Use a small surface area for the last grit and careful placement/contact with the steel to avoid fish hooks. After that a quick FeCL dip and continue with the 600. If you don't like the way the etch came out, no harm as the 600 will remove the etch in a few minutes. My preference right now is to follow up the 600 with a 3000 grit polishing sponge to soften up the grit lines a little.
 
I got the same pattern while messing around with forge welding. WAY overheated. I agree that it was probably HT'd as stainless.

BTW... I still couldn't pattern weld to save my life.
 
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