Harbor freight sharpener

[daddo]

There is a reason dedicated sharpening services charge what they do. Good equipment costs money. There is a reason Forrest asks you to send blades back to them to be resharpened. Tooth angles and clearances are critical. I have yet to see any machine tool from HF that is worth the price of scrap metal.

  Yes and there is also a reason GM always says to only use genuine GM parts or their lubricants, though some aftermarket parts and lubricants can be even better. Guaranteed income.

 I would never advise anyone with a high dollar blade to risk sharpening it themselves if they don't feel competent doing so. My blades are not high dollar blades or with alternating angles.
  I choose to study the science behind tools because of curiosity, you could say I love knowledge and I love doing things myself, whether that makes me more independent or just crazy is up for opinion.
 I cut cutting tools for the lathe and mill and I've found it very enlightening learning the reason and purpose of angles- I have experimented with good success.
 Blades will have- "Tooth angle", "Rake (Or Hook)", "Anti-kick back shoulder" and the "Kerf"- some blades have alternate designed teeth to help flatten the final cut. No rocket science here- basically you need worry about the tooth angle and rake when touching the surface off for sharpening. Setting up a dial indicator will show you if the blade is out of round and a tooth is off.
 The diamond wheel removes very little material, so you would have a hard time messing up and removing too much at one time. (We are talking carbide blades here).
 I completely understand the way you feel. The unknown is scary and mysterious, but believe me, step over that barrier once in a while and you just might learn something. If it doesn't perform the way you like, then send it off and let a pro do it- no harm no foul.

  I seen a lot of people stub there noses up at HF tools, but I'll tell you now- They do have junk, but they also have very well functioning tools you don't know about because I'm sure you haven't tried them all.  A lot of their tools need modifying and afterwords function as well as tools costing many times more, but we will leave that to the shop guys with the skills to do such things they learned by doing.

[Jack01]

 I don't have any pictures and that would be the only way I could describe the mods in a way you would understand. When I get time, I'll do the pics and explaining.

Did you get time take some pictures.
I am curious on this improvement.

[daddo]

I had looked on the net for a sharpener of quality, but after running into the unknown cost of things, I figured spending $1,700.00 to $15,000.00 might be a waste of time, since a $50.00 - $100.00 blade lasts me many years and I may not get my money back, even if I started a blade sharpening business, it could take decades- and I don't have that much time left. I chose to experiment with the HF sharpener because it looked expendable after the sale and % off coupon, the wife wouldn't leave me and my stress level would remain just below the acceptable limit of the  zone where heart attacks are known to happen.
  The HF sharpener is the usual tool that sits on all their shelves- a "go" or "no-go" right out of the box, and the infamous "I can make it work to my liking".  "To my liking" is an opinion, a state of mind or expectations sometimes thwarted for monetary reasons.
 The first time I used it out of the box I hated it. But being in the "I can make it work" mode as I always am, I decided to fix it's worst and even obviously simple irritations- to a limit.

   The pic below shows what I had changed "To my liking" and made it acceptable.






A. There was too much play in the slides. I'll show that later.
B. I changed the existing bolt to a thumb screw for quicker adjustments.
C. There was a knob here that was too large and couldn't be tightened well enough to prevent slippage. I made the handle which works fine.
D. I added a heavy washer on top and in the track on the bottom. The bottom washer needs to be ground down to fit the track. This stiffens
     the shafts position quite a bit.
E.  I had to add lock washers here- the nuts kept coming loose when adjustments were made.
F.  The knob here was frustratingly slow to screw on and off and it would rotate out of position while turning the blade- This slip on makes it much faster
      and it keeps it's position.
G. The T-nut is easy and quicker for tightening/loosening.
H. Tack welded washers on head bolts means not having to find a wrench.
I.  This spring action mechanism was sloppy and would not position itself the same each time. I made a special thickness washer and polished it.



   Underneath the motor mounting bracket and slide plate thingy, there was too much slop allowing the motor to move easily while sharpening.
  The plate underneath had rough edges that would bind with the sliding rods if you attempted to tighten it to remove the slop. Cutting those sharp edges down and polishing them allowed the unit to slide much easier. Some playtime with this one- adjusting it and possibly changing the plates thickness or geometry may be needed. A friction nut is a must here.




Check all angles of the blades and write the specs down before starting.


The best way I have to check angled cuts.




Other stuff;





 I know the guard isn't on- I don't use it- that blade won't eat the fingers,  But I do ALWAYS wear a mask- Carbide is very dangerous to the lungs.

[Grandpa Dave]

 I don't have any pictures and that would be the only way I could describe the mods in a way you would understand. When I get time, I'll do the pics and explaining.

Thanks for taking your time to post pictures and the supporting text behind the mods. I've copied and saved both for future reference. I've had the same unit for some time but only out of the box initially to make sure everything was there and the motor operated. I expected it needed tweaking before providing a repeatable grind but like many other projects, still hunting for the round-tuit.

I've watched numerous You-tube videos of others mods or attempting to use NOB. Some with good results; others should have spent the money on a new blade. There seems to be a number of similar models with different branding. Most are much higher priced than the H-F.

I've acquired several HSS blades from 6-1/2" to 10" too which I'd like to refurbish especially the plywood blades; also have carbide blades in the $25-$100 range to touch up. I've also purchased several HSS & carbide blades from flea markets & yard sales for next to nothing. I figure those will work for my learning curve and worst case scenario will make good, one-time demolition blades.

Again, appreciate the post.

[daddo]

One note.

The diamond wheel should be used only on the carbide blades/tools- not HSS. The HSS will eat away (corrode and load) the carbon in the diamond and make the blade useless quickly. This goes for regular steel as well.

HSS can be sharpened using a regular grinding wheel or better yet a CBN wheel.

[Grandpa Dave]

One note.

The diamond wheel should be used only on the carbide blades/tools- not HSS. The HSS will eat away (corrode and load) the carbon in the diamond and make the blade useless quickly. This goes for regular steel as well.

HSS can be sharpened using a regular grinding wheel or better yet a CBN wheel.

Good points & reminder...mine (HF Blade Sharpener) came with wheels for both carbide & HSS/steel.
Thanks again for the great tips. Now just need a few round-tuits.

[daddo]

Good points & reminder...mine (HF Blade Sharpener) came with wheels for both carbide & HSS/steel.
Thanks again for the great tips. Now just need a few round-tuits.

  I forgot all about that super fine grinding wheel. I'll have to dig that out, it would be perfect to put a fine finish on some cutters.