[jumpinjackflash]

Being a bit of a scrounge and hoarder I have decided to make my own grinder. It all started with a Ryobi 14v battery powered saw with a missing battery and charger. Some parts from one of my other hobbies and a bit of milling machine time. I picked up some 280 grit diamond wheels off fleabay for a good deal last year. It was high time I made something useful from some of the parts { wife classifies as junk} I have on hand. I use a lot of the Meanwell brand power supply units...so one 12 volt - 50 amp unit was donated to this project. There is a potentiometer to adjust the voltage up to near 13.8 volts and it worked out great. Cant speak for any other battery powered saws...but this was pretty easy to work out. So far I have less than $55 in it and can duplicate my grinding every time on 1/16 tungstens quick and easy. Consistency was the goal..and a cool side project.
Pic shows the tungsten in flattening and sharpening blocks and positions. Dust cover coming soon as it does what I wanted it to do for me. Happy so far.

[jumpinjackflash]

This is the results. Same every time....only have to use a stop block after grinding the flat and then setting tungsten in a collet holder to get the flat the same size every time. One more of my issues to eliminate from the possible problem list. I think the DGP units are ground with a much finer wheel...maybe in the 400 or 500 grit range. I am looking out for a wheel that will help carry electrons smoother off the end...I was told it helps a lot at low amps and fine work. Hope all this might help someone else on tight funds this time of the year . I just need to learn to weld better and getting things that could go wrong out of the way is good time spent making a tool .

[Poland308]

Nice! Did you use the original arbor from the saw? And did you have to machine the diamond wheels to get them to fit or make some kind of adapter or spacer?

[jumpinjackflash]

Yes there was some pondering time on that. Couldn't crush diamonds into my lathe chuck. Plus the saw arbor off the gearbox has a "D" splined shaft for a big flat drive washer to keep the blade square with the shaft. So I decided to just machine a bushing to go inside the wheel to center it on the shaft with the retaining bolt so I could easily change wheels. Just have to make a bushing for the new wheels as I try them. Just tried to make use of what I had that was in the saw....thinking it may be something somebody else would want to try.
One thing I have forgot to mention...there was a set of rubber isolator bushings on the screws that hold the motor to the gearbox. I think it was in a free floating area inside the housing. Took the gearbox apart...done away with the bushings and rubber parts and it tightened up nice to the gearbox. Reassembled and was good to go. It turns at just the right speed it seems for a 2.5" wheel. That DC motor zings! Going to have to keep dust out - it moves a lot of air too.

[Poland308]

And this is why I need a mill and lathe !!