finishing, polishing, and sharpening an old restored knife.

TiSurvival

TiSurvival

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Jul 7, 2006
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I bought an old mora puukko that I somewhat restored. I have very limited knowledge making knives and working with steel.

I sanded the blank by hand by laying a piece of 200 grit paper on my drill press table, then I went to 400, I then went to 1000, and finally polished it with white compound. There are still some scratches or marks on the blade and I want to get it to a mirror finish. But here is the second part of the question.

The knife needs to be sharpened. So I was thinking about sharpening it the whole width of the blank, Im not sure if that should even be done, so thats why I am asking on here. I looked over a website that talked about finishing blades and it had some very useful info, but I still cant get the blade polished. I am not sure if its that I need to hit it with the heavier grit longer, or I need to hit it with the lighter grits longer, I dunno. Any help with this would be appreciated.

Also, when gluing the blank to the handle, would 60 min epoxy be the best choice?

The knife is by no means finished so Id like to get it looking sharp with your help

Here are some pictures:

morapuukkobefore.jpg


ghostgreeng-10knifeandsteel.jpg


bladescratches.jpg
 
As far as polishing goes tt looks to me like you still have scratches that are too big to remove with fine grit or polish. To remove them you want the coarser grit. 200# may not be coarse enough. You have to decide what grit to start with, but when using the coarsest grit you chose all the scratches bigger then the ones you are making with that grit need to come out before moving on to finer grit. If they don't come out in a reasonable time you need to back up and start with a coarser grit.

Again, you need to start with a high enough grit to remove any scratches or gouges bigger then those you are making with that grit. Anything bigger will not come out with progressively finer grits (or it will take a long time).

After that you are just removing the scratches from the previous coarser grit with each successive finer grit and your choice of grits and progressive jumps is reasonable. You might through one more finer sandpaper grit in there before the compound, like 1500 or 2000.

When you switch from flat sandpaper to a soft backed medium like a buffer wheel and compound you stop flattening the surface and start rounding the high spots in to the lows of the scratchs so it gets more shiny, but also more wavy and that can affect reflections and the mirror effect you are going after. Holding out with finer flat paper longer before going to a polish (assuming it is on a buffing wheel) will help. You can also lap the surfaces on a stone or other media like leather

What white compound is it, a wax bar on a buffer or a paste compound out of a can?

Gary
 
thanks for the help Gary. The white compound is one I got at harbor freight that comes with buffing wheels, its looks like a piece of chalk but its pastier and its wrapped in plastic. I also have a tube that's cardboard with red compound that I know is rougher. I will pick up a bunch of different sand paper and start again and see. Will keep you guys posted.
 
Go to lows and get one each of the compounds they have. No more sanding will be needed, just use each one and by the time you are done it will look like a mirror.
 
knifenut, when you use those compounds do you have to clean the wheel after you change compounds or do you need to change the wheel? If cleaning, how do you clean? what section of lowes can the compounds be found at?
 
thanks for the help I think I will give the compound a try how many different ones are there?
 
Never mix buffing compounds on a wheel. It is not possible to remove the heavier grits from a buffing wheel. Always use a wheel dedicated to a particular grit.
The blade should be sanded to at least 600 grit before buffing. Make sure all previous scratches are removed before going to the next grit.
 
Knifenut is probably correct about going right to buffing compounds now. I was considering the first picture which is quite rough. Now that you have it refined it with sandpaper it is probably ready for the buffing wheel. What I said about flatness still stands though. If you take too much off with a buffing wheel it will be wavy.

I agree with Bill. I wouldn't mix compounds on a wheel as a discerning user. I have done it, but you never get the coarser grits out. I would suggest a wheel for each grit.

60 minute epoxy would work for setting the handle. Generally, the slower it cures the more penetration you get into the pores, etc and the stronger it turns out.

Gary
 
The compounds from lows (if you have them all) will polish out a metal surface that has only been finished to 220 grit, trust me I've done it. If you have a spur using seperate wheels is not needed, though not 100% of the previous grit has been removed it does not effect the next grit if you have cleaned the wheel properly.
 
Knifenut
Please stop posting things you know nothing about.
Anyone who professionally uses buffers will tell you that you can not achieve a finer polish with ANY remnants of a coarser compound on a polishing wheel.
I have been polishing knives for about 40 years. How long have you been polishing them?
I'm telling the OP how to do it properly, and keep sharp edges.
 
Bill DeShivs said:
Knifenut
Please stop posting things you know nothing about.
Anyone who professionally uses buffers will tell you that you can not achieve a finer polish with ANY remnants of a coarser compound on a polishing wheel.
I have been polishing knives for about 40 years. How long have you been polishing them?
I'm telling the OP how to do it properly, and keep sharp edges.
Click to expand...


Well were not talking about the edge, were talking about the finish on the blade. I also have plenty of experience with polishing though not as much as you but still quite a bit. I have used one wheel and all the lows compounds to polish and as long as I used my spur I had no problems.

Having a wheel for every compound is ideal but by the time you get all the compounds and wheels needed you could have payed someone to do it for you for less. The OP may want to get enough wheels for every grit but I was just letting him know of a quick, cheap and easy way that does work.

I understand your points but lets try and not be insulting.
 
I'm not insulting, I'm telling the truth.
Never mix compounds on a wheel, unless you are going to a coarser grit-then the wheel is not useable for finer grits.
As far as sharp edges, I was referring to grind lines, not the blade edge.
Your way may "work" but the finish could not possibly be uniform. I try to tell people how to do things the right way. Sorry if you feel insulted.
 
I don't feel insulted just that you were trying to be insulting. I know its best to use a different wheel but I have used one wheel with different compounds and it worked fine, and yes the finish was very nice and uniform. I don't use it much so that may be the reason for my results, I could understand how if you do a lot of polishing it could be a problem.
 
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