Looking for a short cut

wmhammond

Well-Known Member
I hand sand every blade I make, no shortcuts, no exceptions. After heat treat and tempering I begin my finish grind with a 3M 337DC A100 Trizact Gator Aluminum Oxide Abrasive Belt, then I go to an A65, then to an A45 and finally to an A30 (600 grit). I also have a glass platen on my 2 X 72 grinder. No matter how careful I am I still come off that 600 grit belt with scratches that are so deep that I have to start hand sanding with at least 220 grit paper. I'm looking for suggestions of other techniques or other products that would minimize these scratches.

On another note, I have seen a maker on You Tube use an Oscillating tool to "hand sand" with. Has anyone tried this and does it work well enough to justify purchasing one such tool. Thanks so much,

Wallace
 

tkroenlein

Well-Known Member
Try doing your post heat treat grinding starting at 120, then moving to an A160, then on with what you usually do.
 

tmr

Well-Known Member
I get good results with a rotary platen running slow.......also finish up with a 3m micron finishing belt 30 micron and then 15 micron......there is a huge difference between the trizact and the micron belts for finishing......i usually stop at 45 on the trizact and got to the micron then
 

Kev

Well-Known Member
I could be entirely off base here, but it sounds like you may not be getting all of the scratches left from the previous grit, before moving on.
one thing I’ve tried with varying degrees of success is to cost the blade with magic marker, and then run it across the belt. This will show low spots, or scratches. I know it sounds trivial, but after I started this process of removing every scratch left from the previous grit, I can move up to 609 grit in a heat treated blade and hand sand the entire blade in 10-15 minute tops. Most times I can start at 320, but I normally do 220 to start.
 

JeremyBartlett

KNIFE MAKER
I do similar, I go from 60, 120 in ceramic, to a45 and a30, then off to my disc sander at 600 grit. You wouldn't believe how "not" flat your bevels are until you hit them with a disc sand. I'll do 600 and 800 on the disc then go back to 600 hand sanding. Every since I started doing it this way my hand sanding time has been cut dramatically
 

Smallshop

KNIFE MAKER
Walmart's "hypertough" brand corner sander is about $20 if I recall...I bought one to try. 2 yrs later still using it ('course one of those years it sat...). I use mc master carr sanding triangles as they are bigger so I can go right into the plunge area...I also believe they are better quality than Wally's house brand. A cheap way to try before you buy a good one...
 

EdCaffreyMS

"The Montana Bladesmith"
YEP!! Every since I got sick, and my body has gone south on me, the oscillating tool has become my go to for "hand sanding". Personally, I use the 18V Makita variant, but all the battery tools in my shops are either Ridgid or Makita.

The key to making it work for finishing blades is the attachment you use..... ALL that I have found have a velcro face....and that just doesn't work. I like this particular attachment for sanding.... https://www.acehardware.com/departments/tools/power-tool-accessories/backing-pads/2201945 because it's MUCH heavier duty them most others. As soon as I take it out of the package, I take it to a 50 grit belt/flat platen, and gently grind off all the "hooks" on the velcro. Then use a low tack spray glue/adhesive to hold the sanding paper in place.

Speaking of sanding paper..... another key is using QUALITY sandpaper.... I use the same that I do for hand sanding... RhynoWet Redline. Using the attachment, I stack 5-8 sheets of paper, and trace on the back, and cut out all the sheets at once. It will seem like you go through a lot of paper when using an oscillating tool/sander....but you don't.

Once I get things to the grit finish I want, I go over it by hand, to make the scratch pattern run/follow the length of the blade.
 

Boatbuilder

Well-Known Member
I now go from 220 off the 2 x 72 grinder to the disc grinder. I start with 220 paper and go up from there. I find if I run my disc grinder at 20% speed it cuts better and the paper lasts longer. Good sandpaper is a must on the disc grinder. I use either rynowet or black ice. I cut my paper so it over hangs the disc by 1/8 approximately and this allows me to clean up the heavy scratches in the plunge area. My disc grinder has 1/8" cork backing on it and I use feather adhesive to keep paper on.
 

scherf68

Well-Known Member
Are you guys still using windex or water when utilizing oscillating sander? I have one but corded, just want to clarify before I attempt to kill myself.
 

EdCaffreyMS

"The Montana Bladesmith"
I don't use any lube.... it's more hassle than it's worth. Spray, sand, find a rag, wipe, look to see where your at, repeat. ;)
 

Kev

Well-Known Member
I tried the oscillating tool approach today, and I was pleased. I followed Ed’s directions and ground the Velcro off the pad. For me it was still too spongy and I felt like I was rounding over lines more than I’d like. To remedy the made a copy of the pad shape with some 1/4” plywood (on that note, I think Masonite or something similar would work better) and glued that on. For a first go I thought it worked great.
I already had the tool, so it wasn’t a huge leap. But for those buying a new one, the quick release type would be more convenient that the retaining screw that I have. For what it’s worth.
To test I ran the blade to 400 on my 2x72, then 400 on my disk. After that I used the oscillating tool starting at 220 up to 600. After that I straightened up the lines with 600 grit, no real need for any other hand sanding.
While I don’t necessarily think this is the magic pill, so to speak, it does a good job. I didn’t notice any appreciable savings in time, but it was my first go.
 

EdCaffreyMS

"The Montana Bladesmith"
You do have to be conscious/careful of varying planes of the blade your sanding...that meaning that you go up TO, but NO OVER the plunges and other lines...just like you wouldn't do that on a belt.

It can be tough to find the pad that "fits" you the best. I went through a few brands of sanding pad/attachments and finally settled on the Dremel brand.... it seemed to have the hardest "pad" after I'd ground off the "hooks" on the Velcro.

I was thinking of ordering a thin piece of hard urethane from McMaster-Carr, but that's likely more trouble then it's worth, since I found I like/got the Dremel pad to work well.

It's certainly not a huge time saver.... but with me having this stupid Lupus, and many days my body hurts so badly that hand sanding like I used to is VERY painful, it's a way for me to keep going, when I don't feel like it. :)
 

Taz575

Well-Known Member
I tried this once, but with the velcro pads, didn't work well at all! Completely missed about grinding the velcro stuff off and using feathering adhesive! I may have found a use for the multi tool finally! I tried it with blades for cutting metal to try to cut some mild steel and angle iron and it didn't work well at all.
 

EdCaffreyMS

"The Montana Bladesmith"
Based on my own experiences, I consider Oscillating tools are the "scalpels" of the saw world..... delicate, precision, and hard to reach are the best uses for sawing with one. I actually purchased mine because I was installing a dishwasher in my daughter's house....where she has 1940s cabinets.....meaning the were built into the home. Had to do some fairly intricate cutting, that any typical saw would have wrecked.

When it comes to sanding, it's the same thing, more a detail type sanding scenario, rather then removing material. When you consider that a single 9x11 sheet of sandpaper yields 10-11 pieces that fit the sanding pad..... If I can get through a single side, on a hunter sized blade with 5-6 of them..... that's as good, or better then I can do by hand/with a sanding stick.

I consider it just a way to work a bit smarter, versus harder. :)
 

Kev

Well-Known Member
It's certainly not a huge time saver.... but with me having this stupid Lupus, and many days my body hurts so badly that hand sanding like I used to is VERY painful, it's a way for me to keep going, when I don't feel like it. :)
I’m in the same boat (not Lupus but similar. I think that adding this little trick to my arsenal, is just one more thing to keep me going.
As far as the pad goes. I figured a little scrap wood and glue was worth a shot, it worked but I’ll keep experimenting.
 

EdCaffreyMS

"The Montana Bladesmith"
If you can find/apply a thin/hard rubber or urethane material, I think you'll find it works well. I did that prior to figuring out I liked grinding the hooks off the velcro.

I also think it's important to note that the oscillating sander works best with minimal pressure, and just more or less "guide" it around. I found that if I apply too much pressure, it doesn't sand as well, and it will eat up a battery on mine in short order (I have a Makita 18V).
 
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