Hand sanding final grits

I

Ian Fifelski

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Oct 4, 2017
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I have been hand sanding a blade for a while and got it up to perpendicular 1000 grit and then did length-ways sanding with 1500 grit. I got all of the perpendicular scratches out and started doing only pull strokes. I used a whole redline sheet trying to get the back-and-forths out without any luck. All this took some hours.

My question is, am I doing something wrong? Is there a trick or technique to get the back-and-forths out? I have hand sanded a couple other blades and it took a good amount of time but not nearly this long to sand to an even finish.
 
There are probably several ways to proceed, but I would suggest, Once you get done with your perpendicular 1000 grit, cotinue lengthwise with the 1000 grit using pull only. Once all signs of the perpindicular are gone go to the 1500 and repeat pull only. If you find you are leaving fish hooks when you set the paper down, try using WD40. It has a tendency to float the paper until a slight pressure is applied. If you are using a stick make sure you pull evenly with both hands.
Jim A.
 
sounds like you are still fighting 400 grit scratches with 1500 grit paper. if you switch the direction of your sanding every time you change grit, you lessen the possibility of missing earlier scratches. i sand at a 45 degree angle to the upper left, and on the next grit 45 degrees to the upper right, then back to the left.
 
john april said:
sounds like you are still fighting 400 grit scratches with 1500 grit paper. if you switch the direction of your sanding every time you change grit, you lessen the possibility of missing earlier scratches. i sand at a 45 degree angle to the upper left, and on the next grit 45 degrees to the upper right, then back to the left.
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Yeah, this is what I have done. Every grit the perpendicular to the last.
 
DAMNENG said:
There are probably several ways to proceed, but I would suggest, Once you get done with your perpendicular 1000 grit, cotinue lengthwise with the 1000 grit using pull only. Once all signs of the perpindicular are gone go to the 1500 and repeat pull only. If you find you are leaving fish hooks when you set the paper down, try using WD40. It has a tendency to float the paper until a slight pressure is applied. If you are using a stick make sure you pull evenly with both hands.
Jim A.
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I will give this a try. Thanks:thumbsup:
 
Angle your tip down in the vise or whatever you’re using to hold the knife.
I also do pulls dry on the final stages.
 
It sounds like you might not be changing your paper enough! Sandpaper is cheap; time is not.

Windex or WD40 and softer backing for the final pulls can also make a big difference.
 
in your original post, when you say "back and forths" are you talking about the marks the current paper makes when you change directions, or the direction changing marks from the last grit ? i am assuming for the final pulls you are not stopping or changing direction anywhere on the blade.
 
HIGHLY recommend EDM stones.
Also a disc grinder with sandpaper glued to it not only makes it flat but gives a nice finish before you start hand sanding
 
john april said:
in your original post, when you say "back and forths" are you talking about the marks the current paper makes when you change directions, or the direction changing marks from the last grit ? i am assuming for the final pulls you are not stopping or changing direction anywhere on the blade.
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Yeah, I am talking about scuff marks the current grit (1500) made when I was sanding back and forth when starting with the grit.
And yes I am doing only pull strokes.
 
in my experience, those direction change marks always seem to be deeper than the rest of the scratches and seem to take 3x longer to remove :( i cannot find an explanation for it, but i am guessing you are not doing anything wrong. those sanding blocks seem worth a try.
 
E.Carlson said:
When I can't get my final finish right I put it down, go to sleep and try again in the morning. Works every time!
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I did just this and things are looking good. I also found and using the sanding stick at an angle when at the plunge and slowly angling it down to flat reduced making more back-n-forths.

Thanks for the tips all!
 
Seriously watch the Wheeler video and do just that. No that I know of does it better than him!
 
john april said:
in my experience, those direction change marks always seem to be deeper than the rest of the scratches and seem to take 3x longer to remove :( i cannot find an explanation for it, but i am guessing you are not doing anything wrong. those sanding blocks seem worth a try.
Click to expand...

My guess as to the reason for this (coming from a physical therapist/biomechanics point of view) is that when switching directions you are changing muscles from extensors (pushers) to flexors (pullers), and the flexors will try to pull your hands off the blade, so you can tend to use more force to keep the block and paper in contact with the blade. Also, when switching from puller to pushers, we tend to initiate the push with a little more pressure than necessary. One possible way to avoid this problem is to slow down a little, especially when switching directions.
 
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