Homemade Sawmill Band Saw Blade Grinder/Sharpener -No Welding. Spencers-Mountain Off-Grid

*Full List of Parts below*
If you have a sawmill, you need sharp blades. You can buy a lot of blades for the cost of a blade sharpener. But there can be five or more re-sharps in a blade getting more for your investment. Sending blades out to sharpen is not cheap and takes time. If you build a homemade DIY sharpener, that option achieves quicker payback and becomes very attractive. Here is one way to build a low cost sawmill blade sharpener with purchased parts (but scrounging, used parts and repurposing is highly encouraged). No welding and can be done with hand tools and a drill.
#71 I built my sharpener for 12v operation to run off solar or sawmill battery making the best of our Mountain off-grid self-reliance. Being able to make a dull blade cut again can be important when the supply chain is broken, or a sudden need arises.
Specs on mini 2/3 CIM grinder motor 217-3317:
Battery In: 12V DC
Outputs: Shaft size - 8mm (0.314in) with 2mm keyway
Free Speed: 5,840 rpm (+/- 10%)
Free Current: 3A
Maximum Power: 215 W
Stall Torque: 1.4 N-m [12.4 in-lbs]
Stall Current: 89A
Mounting Holes: (4) #10-32 tapped holes on a 2" bolt circle
**Parts List **
*As an Amazon Associate I earn from qualifying purchases*
1) Bud Industries aluminum enclosure: approx.: 8-5/8"x5-58"x3 -1/4" amzn.to/3K4O2iU
1)Gear Motor: 12v 16rpm 750kg/cm amzn.to/3JCSZPW
1) Oregon Chainsaw Sharpener grinding wheel amzn.to/3I8zWfX
1) 8mm Flange Coupler: amzn.to/3LXJVqW
1) Grinder Motor: Mini CIM 12v DC
2) Motor Switches: 12v DC SPST Toggle: amzn.to/3BOP7J7
2) Motor Switches Boots: amzn.to/3I9bFXk
2) Inline Fuse Holders: amzn.to/33ztgbI
1) Battery clip: amzn.to/3v85ajE
2) #10-32 threaded rod (height and pusher adjusters) amzn.to/35btW7A
1) 3/16" Spherical Rod End amzn.to/3BxYcWs
2) #10-32 Brass Thumb Nuts
1) 10-32 acorn nut
1) 1/4"-20 x 3" Countersunk Screw (blade guide attachment)
3) 1/4" -20 x 1-1/2" fully threaded screws (blade guide)
Misc 1/4-20 nuts, washers, fender washers and screws as needed.
1/4" ball bearings (lift arm and push lever) amzn.to/3I9cob0
8mm ball bearings (Grinder mast pivot) amzn.to/3s1Ol8b
special tools--
drill bits and 10-32 tap amzn.to/3p3L2LH
drill bit and 1/4-20 tap amzn.to/3H41e5V

[@charliesaul729]

Your builds are second to none. Tremendous creativity, skill and finishes. Great teacher and adult education. Finest example of the power of KZbin to inspire good work, even if largely unrelated.

[@SpencersMountain]

Wow! Thanks! Glad you enjoyed the video. I truly believe people are capable of anything they set their mind to accomplish. Thank you for giving your time to watch my video.

[@rexhavoc2982]

Place a magnetic parts dish behind the grinding wheel and catch all the chaf. The more chaff the better it works.

[@SpencersMountain]

Great idea. Could benefit a lot of viewers including myself. Appreciate your support!

[@pedrodelgado3879]

Nice! Now go out and mass produce this baby!!! I'd buy one.

[@SpencersMountain]

There are companies making sharpeners. Savings comes from building your own. Thanks for watching!!

[@jameskemp1717]

Would u make me saw blade sharpener

[@SpencersMountain]

Thank you for the confidence. Unfortunately, we are so buried in projects, there is no chance to do other work. There are many commercial sharpeners available to choose from that provide product support and parts. If you can justify the cost, sharpeners can be the best path. Thank you for watching.

[@northcountrytrapper5607]

Some people’s brains just work better than most!!

[@matthewprestine1974]

Nice build. I created a spread sheet that can automatically calculate that cam profile base on grind depth and tooth pitch. This way you can just print it off to scale and laminate it over the stock to cut it out. I can put a link to it here if you dont mind.

[@SpencersMountain]

Thank you. The spreadsheet is a cool idea. I use CAD for my designs but CAD is not for everyone. You can post the link to aid other people. Thanks for watching.

[@daveb8598]

That is awesome, I'd appreciate the link if you could post it or send to me!

[@SpencersMountain]

@@daveb8598 I am sorry, which link were you looking for?

[@ljfleetwood9035]

Please share your cad drawings if possible...

[@SpencersMountain]

@@ljfleetwood9035 I put the drawings in the video. These were dirty drawings and not much good by themselves. Just wanted to share the basic idea and let others make up their own machine. Thanks for watching!

[@jamiep5660]

Any chance you can make the shaft adaptor go a 1/2 in arbor 3/8 wide stone? Cost?

[@SpencersMountain]

Sorry. I am not able to make parts as we are often where the machine tools are not.

[@sent6XC]

Was the motor you used strong enough? I am planning to build one but was thinking of upgrading to the Vexpro #217-2000 to add a bit more power. Thanks!

[@SpencersMountain]

I was concerned about the power of the grinder motor initially, but in use, I have not seen any problems. The way the grinder cycles, the motor gets back up to full speed. Ultimately, you are only removing a few thousands of an inch at a time and you do not want to overheat the blade and change the hardness of the blade. I have not noticed any discoloration on my blades where the grinder has sharpened the blade. Can't say I have even noticed warmth in the blade near the grinder. I think the Oregon 60 grit grinding wheel has a lot to do with that. Cheaper wheels tend to dull quickly and rub more than grind. Nothing wrong with going bigger is you have the power to run the motor. I went small partly due to the weight the gear motor has to lift. The gear motor seems powerful enough...just don't know how durable that motor will be in the long run. Thank you for watching our video.

[@sent6XC]

@@SpencersMountain Great! Thank you for the reply.

[@natsusalamander2303]

you do a professional job,, thx for all the draws. can you do a draw of cam that drive the mecanism

[@SpencersMountain]

The cam is specific to your saw blade. You still have to go through the process I showed to make your cam suit your saw blade. Wish there was a better answer, but I have not found a better way yet. Thank you for your comment and thanks for watching.

[@oby-1607]

If you can make a blade sharpener(which any sawyer needs if cutting wood), you can make a bark cleaner. Its really just a spring loaded small circular saw that is ahead of the blade and makes a cut line thru the bark so the blade doesn't encounter the sand in the bark. Maybe a future project. Thanks for sharing.

[@SpencersMountain]

Guess I have another project! Thanks for watching!!

[@KnowArt]

damn, what a build! great job

[@SpencersMountain]

Thank you. It is fun to build useful things. This machine is mesmerizing to watch run. Thanks for watching.

[@RAYAR54]

That's a nice build. The corners of the teeth would likely have the most wear and touching off the back of the tooth also would bring back that full width cutting edge in likely one pass.

[@Jesusis]

Congratulations on a fabulous build video…I am tempted to build this sharpener despite the fact I have no saw mill…or need to sharpen a band saw blade of this size. 😂😂😂 your work on mill was also very comprehensive…thoroughly enjoyed watching all from my arm chair. Best wishes.

[@SpencersMountain]

Thank you! Sometimes it is just fun to make things. This kind of machine is nearly hypnotic when running. Good luck with your projects. Hope you produce a video. Love to see the results. Thank you for watching.

[@Jesusis]

@@SpencersMountain I happened to find a mandrel on Amazon with a 8mm hole and a threaded end matching an angle grinder with 7/8 hole flange and nut to affix a Oregon grinding disk to a CIM motor…so machining an adapter is not necessary. It’s under M10 mandrel adapter. This would greatly enhance people using your site to duplicate the grinder. Wish I could send you a photo of page on Amazon…I just don’t know how. Best wishes, thanks for the reply. 👍👍👍

[@SpencersMountain]

@@Jesusis thank you for providing solutions for other people. I can make nearly anything I want, but want to share ideas that others can reproduce without special machining or welding when possible. This should help out others that take the time to search the comments.

[@timeubank6228]

Always amazed by what you do .. great video as always . You have inspired me to build my own saw mill and now I’m inspired to try this blade sharpening device… thank you for the videos

[@SpencersMountain]

It is awesome to hear from a repeat viewer! I am so happy you found inspiration in our videos. Best of luck on your projects and be sure to share. You will be the next inspiration. And, thanks for watching!

[@jerodlyford10]

Rough estimate but 2000.00 in labor. 100.00 in parts. 700.00 to buy one. That being said, you still built a great sharpener that looks professional and precision. Love it.

[@SpencersMountain]

Wow, great wages! Seriously, not that many built time hours. Even harder to put a price on making something by yourself. For the guy making money cutting wood, buying a sharpener is a good choice. For the guy that just enjoys making things, priceless. Appreciate the comment and thanks for watching.

[@nightflight2112]

You should have2.23 million subscribers. This is the most detailed video I have seen on an auto blade sharpener. Kudos Sir, keep on keeping on.

[@SpencersMountain]

Thank you for the kind comment. I learn from others videos. Only seems fair to pay forward. Thank you for watching!

[@daveb8598]

This is awesome. I love the compact size compared to other setups. I wonder if you add a few return springs to take gravity out of the equation, if you could sharpen blades right on the saw, might need a stop, but I think the little gear motor could spin the blade if the blade is free spinning

[@SpencersMountain]

It is possible to sharpen a blade on the saw. In my research, I recall a Dremel tool based on-the-saw grinder, but they warned it was more of a temporary / emergency device. The spring idea could work, A counterweight might also have a similar function (weight on rod to hold grinder head against cam. Ultimately, it is not a huge deal to change blades, as you will have to at some point anyway, and save dulled blades to sharpen in one run. Still an interesting idea. Thanks for watching.

[@PaulWhitedWoodStoneIron]

Nice job. Another well explained video. Great job. Thank you.

[@SpencersMountain]

Thank You! Hope it helps give others inspiration to try building their own things.

[@rickymeadows5176]

Absolutely AWESOME build ! Thank yo so much !

[@SpencersMountain]

Thank you. Thanks for the comment and thank you for watching.

[@MrSplee1b]

Is there a way or place I could find a digital copy of your prints? I would like to attempt to rebuild your blade sharpener, with your approval of course. Great job on the video and explanation of how to do everything. One last question, do you just run the blade one full rotation, or multiple?

[@SpencersMountain]

I included the drawings and some dimensions in the video to avoid providing some sort of download. The drawings I used were not proper drawings but have adequate information when used with my descriptions in the video. The number of passes on a blade grind depends on the condition of the blade. You can only remove a certain amount of metal from the blade before grinding heat may impact the hardness of the blade. It is best to take small amounts until the teeth are sharp again. That may be accomplished in one pass or could be several passes. Thank you for the questions and thanks for watching.

[@MrSplee1b]

@@SpencersMountain Thank you for the response.

[@toddwheeler1526]

Beautiful work sir. Thank you.

[@SpencersMountain]

Thank you and thank you for watching!!

[@mariopratte374]

how much rpm are the cim motor??

[@SpencersMountain]

Battery In: 12V DC Outputs: Shaft size - 8mm (0.314in) with 2mm keyway Free Speed: 5,840 rpm (+/- 10%) Free Current: 3A Maximum Power: 215 W Stall Torque: 1.4 N-m [12.4 in-lbs] Stall Current: 89A Mounting Holes: (4) #10-32 tapped holes on a 2" bolt circle

[@АлександрПолосьмак-е4м]

Вы молодец! Мастер! Здоровья и удачи!

[@SpencersMountain]

Спасибо за теплые комментарии. Спасибо за просмотр!

[@SteveBowers-h5p]

Hi. Great job on the build. Im wondering...does your lifter arm pivot threw the blade guide mounting hole? Also, what diameter do you rough out your cam blank to? Again, great job and well thought out. Your mill is awesome too.

[@SpencersMountain]

Thanks! The lifter arm is behind the blade guide and is held with a countersunk screw through the blade guide on the left side of the guide flat bar. The plastic cam blanks are 3-7/8” rough diameter. The mill has been a satisfying project. Currently we are trimming glue-lam beams for our house project. Thank you for watching!

[@SteveBowers-h5p]

Thank you. I am confused as to whether or not it's infront/behind?? Of the blade guide mount hole. Don't see it in the drawings. Thanks again.

[@SpencersMountain]

@@SteveBowers-h5p edited the previous post as I was thinking of the advancing arm. The lift arm pivots on a countersunk 1/4” machine screw. You can see the countersunk hole in the left end of the blade guide flat bar. Behind that guide is a plastic spacer then the lift arm another spacer then the case. There is a 1/2” bar through the case for the countersunk screw to thread into. That countersunk screw mounts the guide and provides the pivot for the lift arm. The lift arm has two 1/4” bearings pressed in for the pivot.

[@sweb7680]

Brilliant…

[@SpencersMountain]

Thank you. Thank you for watching!

[@olitomesek9677]

No metric?

[@SpencersMountain]

Sorry, I am an old school American SAE type. I can see things in .001” but mm just confuse me. But there are lots of online converters and even most smart phone calculator apps. Thanks for watching.