Po' Boy's Blanchard Grinder

[Crusty]

Not having the coins for a surface grinder, I tried this affordable alternative today and I'm happy to say "That'll do, pig".

I bought a Dewalt cup grinding wheel and made an arbor for it to mount in my mill and it works.

I spent a little time surfacing this piece of mild steel and while it doesn't look like a high dollar surface grind finish (it's a Blanchard grinder after all and they never do) it did produce a surface that's as flat and smooth as I could hope for and it will work just fine when I need things to slide over each other smoothly and accurately. It's a better surface that I've ever milled with my carbide surfacing cutter.

Everything on the mill must be covered to catch as much grit as possible but plan on spending some time afterwards with an air nozzle and a brush, and make double certain that all of your covers will stay in place as the table travels and watch them closely anyway. I had a bit of trouble getting my cooling mist completely under the wheel's surface and so had a couple of spots that are heat discolored but I think I can solve that issue with more practice using it.

That test piece (which has had only soap and water cleaning after grinding) is absolutely smooth and flat as I run my finger nail across it so I know it will work for my purposes. All in I think I've got less than $30 in this experiment and I've added another tool to my repertoire. If you need a surface grinder and can't afford one, this technique is worth trying.

[DIYer]

Thanks Crusty! We've added your Blanchard Grinder to our Grinding category,
as well as to your builder page: Crusty's Homemade Tools. Your receipt:

Blanchard Grinder by Crusty

tags: grinding, mill

[jdurand]

And for people who don't know, don't blow any air AT any sliding joint or bearing. You'll just embed grit in the joint. Only use a brush or vacuum around the ways or the old tool maker will appear to slap you with the air hose.

[Crusty]

I remembered after the first surface that I hadn't dressed the wheel face true so I clamped my diamond point in the vise and made the wheel perfectly flat and tried it again on the opposing face and I discovered why Dewalt made the wheel with the face angled a slight bit. With the stone face exactly parallel there's no clearance for dislodged grit and the wheel jammed frequently on it, so I'm going to have to put a relief angle back into that stone's face. I was able to solve the heating problem with lots more coolant (but it didn't wash the grit out of the grinding area).

[Frank S]

Years ago I made an anvil out of 2 " thick plates then hard surfaced the face of it with 5/32" Stoody 35 electrodes after I used a 5" cup rock to grind it flat I clamped it on the table of an old 3horse power bench mill that wasn't really much good for much any more. The table had more hole in it than a 2x6 wood block you might find on a drill press but the spindle was still solid. After about 5 passes I had a nice flat face on the anvil

[Crusty]

I've got some 1" plate that I'm thinking of welding to some rr rail to make myself an anvil. I might use my cup wheel on it to surface it afterwards.

[old_toolmaker]

Crusty,

This is one way to grind a surface and it looks like it worked.
Be very careful using compressed air when cleaning machines. The air can and will drive grit into everything and that can and will cause increased wear on sliding parts.

[Crusty]

I only use air to clean out my table grooves, everything else gets brushed out and wiped off. If I remember to wipe everything down before I start so loose grit doesn't stick to anything then my shop vac does a pretty good job. I'm also gonna cut up an old shower curtain for a drape so that no grit can get through it.

It makes really flat surfaces but since I can't rotate the work too like an actual Blanchard the surface doesn't look very uniform but maybe that's a good thing because it should hold oil better than a slick surface.

My little mill is a vertical/horizontal combination mill so I'm going to find a wheel that will go onto the horizontal arbor and try some actual surface grinding. It'll be slow but I'm not on any clock. It'll probably be a while before I go down that road though because the VFD and ¾ hp 3 phase motor that I bought will get here first and I'm rarin' to get on to that project and give my mill some low rpm balls.

[suther51]

What kind of rpm's are you turning. Just wondering as my mill turns 2200 max. Not realy shure what would be a minimum rpm for grinding this way. Suppose I could make a holder for my die grinder.
Thanks for the post

[Crusty]

I want low rpm torque for milling with larger end mills - tired of picking steel splinters out of my hands for three weeks because I have to run the rpms faster than it should be and making clouds of tiny needles. I think right now with the anemic ½ hp universal motor I top out around 2000 rpm.

I made a holder for my Foredom hand carver on my lathe toolpost and it works fine as long as I take shallow cuts since it's hp limited but a die grinder mounted on the tool post could be a poor boy's toolpost grinder. A die grinder mounted to the quill on a mill is an interesting concept for grinding but I generally prefer to run my mill at low rpm and take out bigish chips with end mills.

Actually I'm not really sure why I'm thinking about trying surface grinding because planing in horizontal mode leaves a beautiful flat finish (here's two 1" thick triangles pinned and planed together) and it's a lot faster than grinding. To speed things up I ganged two cutters onto the arbor for the roughing cuts and then finished with a single cutter to level the surface. It's certainly flat enough for anything I might make.