Homemade surface grinder/motion ideas

Hey all,

I'm making a cheap/janky surface grinder out of a cheap bench grinder, lathe cross slide, and some steel tubing. I have the mounting method for the bench grinder and the magnetic chuck figured out, but I don't know a good way to raise and lower the cross slide. I was thinking of using a cheap 32mm cross slide from amazon, link below, but how should I make it travel that vertical distance? It's only a little more than an inch of height in travel, what would be a good way to do it? Obviously trying to keep the cost as low as possible, I'm a pretty novice machinist and this is really the first "tool" I've designed. I have access to an South Bend 9a lathe, a small horizontal mill, bench grinder, and a whole bunch of hand tools. I also have a fair amount of collected scrap material/raw stock.

What are everyone's suggestions?

https://www.amazon.com/gp/product/B08F2M6R3D/ref=ox_sc_act_title_2?smid=A1RXNZT4AK0KHN&psc=1

Fatt Miner said:

Hey all,

I'm making a cheap/janky surface grinder out of a cheap bench grinder, lathe cross slide, and some steel tubing. I have the mounting method for the bench grinder and the magnetic chuck figured out, but I don't know a good way to raise and lower the cross slide. I was thinking of using a cheap 32mm cross slide from amazon, link below, but how should I make it travel that vertical distance? It's only a little more than an inch of height in travel, what would be a good way to do it? Obviously trying to keep the cost as low as possible, I'm a pretty novice machinist and this is really the first "tool" I've designed. I have access to an South Bend 9a lathe, a small horizontal mill, bench grinder, and a whole bunch of hand tools. I also have a fair amount of collected scrap material/raw stock.

What are everyone's suggestions?

https://www.amazon.com/gp/product/B08F2M6R3D/ref=ox_sc_act_title_2?smid=A1RXNZT4AK0KHN&psc=1

Click to expand...

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Fatt Miner said:

Hey all,

I'm making a cheap/janky surface grinder out of a cheap bench grinder, lathe cross slide, and some steel tubing. I have the mounting method for the bench grinder and the magnetic chuck figured out, but I don't know a good way to raise and lower the cross slide. I was thinking of using a cheap 32mm cross slide from amazon, link below, but how should I make it travel that vertical distance? It's only a little more than an inch of height in travel, what would be a good way to do it? Obviously trying to keep the cost as low as possible, I'm a pretty novice machinist and this is really the first "tool" I've designed. I have access to an South Bend 9a lathe, a small horizontal mill, bench grinder, and a whole bunch of hand tools. I also have a fair amount of collected scrap material/raw stock.

What are everyone's suggestions?

https://www.amazon.com/gp/product/B08F2M6R3D/ref=ox_sc_act_title_2?smid=A1RXNZT4AK0KHN&psc=1

Click to expand...

since you are a cheapskate how about this?

https://www.amazon.com/Lukcase-Mult...605554185&sprefix=cross+slide+,aps,156&sr=8-8

just remember aluminum will wear like hell with grinding dust

dee
;-D

Lol, fair enough, I'm actually using something really similar as the cross slide that's left over from an old project. My question is how can I move that up and down?

Functional surface grinders can be had for $500 or less.....

Note this is the is the Manufacturing Forum, not the home shop machinist forum.

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^^^^^^This is the very first rule of this forum^^^^^^^^

However, Just out of curiosity/Amusement, before this thread gets locked, What are you trying to accomplish from a bench grinder? Those cheap 6204 or equivalent dust filled bearings in a motor mounted on a stamped metal plate would leave a finish resembling corrugated roofing.

As AJ said, a decent manual surface grinder will run under 500 at auction.

You don't raise and lower the cross slide. You raise and lower the grinding head.

A cross slide generally has too much friction for the longitudinal travel. IF I were to attempt to craft a DIY grinder I would use the slide for infeed and use a table on linear ways (such as those by Thompson) mounted atop the slide and with a lathe milling attachment (and removable riser blocks) to mount the grinding spindle. The longitudinal axis needs to move smoothly and quickly, actuated by a rack or chain/timing belt setup.

Such a device could also be the basis for a light-duty tool and cutter grinder.

AJ H said:

Functional surface grinders can be had for $500 or less.....

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Good lord, a quick look on ebay and it is flooded with them. Almost got the itch to buy one they are so cheap, then I remembered I have one and almost all I use it for is relieving endmill necks with a diamond wheel

Whoopsie, sorry, didn't realize I posted in the wrong area, but it's more of a space thing. I want to make something that is really small, and I already have a bunch of the parts I would use.

Fatt Miner said:

Whoopsie, sorry, didn't realize I posted in the wrong area, but it's more of a space thing. I want to make something that is really small, and I already have a bunch of the parts I would use.

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Now doo you see what I mean when I suggested ?
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Contrary to some around here, I wasn't being mean, simply pointing out a better place to ask the questions.

digger doug said:

Now doo you see what I mean when I suggested ?
Projects and Articles on Our Forum! | The Hobby-Machinist

Contrary to some around here, I wasn't being mean, simply pointing out a better place to ask the questions.

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No no, I didn't take it as being mean, I'm usually a lone guy that just reads and watches a lot of stuff. I really appreciate the direction.

then I remembered I have one and almost all I use it for is relieving endmill necks with a diamond wheel

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Same here, that little Phase 2 spindexer and Borazon wheel probably hasn't came of in 5 years.

Suggest the OP look locally for a DoAll 6x12 or a Taft Pierce 5x12 or even a little Sanford surface grinder. Can purchase for pennies on the dollar and voila, you have a real surface grinder. Even better if you get the mag chuck and some wheels...

L7

Fatt Miner said:

Whoopsie, sorry, didn't realize I posted in the wrong area, but it's more of a space thing. I want to make something that is really small, and I already have a bunch of the parts I would use.

Click to expand...

The "part" you can get better results with, cheaply, is a hunk of marble door or window sill to serve as a "backing", and an assortment of dry and "wet" abrasive paper.

Eyeball the marble - or granite - they make the stuff pretty damned flat because it has to LOOK optically flat... and is easier to make it flat than to NOT do.

Learn "the motion". "Gravity" is your vertical feed. Reliable stuff, gravity is.

Add Mark One "elbow grease".

Not a lot of space nor money required.

"Skill" .. and how to assess the need, plan the tasking, and check progress.. or LACK thereof... you should learn in any case.

Some 8020, some steppers from a junked printer, and mach 3....Whoopee !

i made a surface grinder by taking an already existing 7 foot long box beam weighing 300 pounds, welding four inverted V pieces to the sides of the beam about 2 feet apart by 1 feet apart, and then laying 2, 1.5" diameter steel rods in the V's

then, by grinding and filing the V's out, the bars were made to be parallel in both axis.

on top of each of the bars sits a two pieces of angle iron with plastic pads that touch the iron round bars. the angle iron is bolted to the 56" long cast iron optical table of some sort, it has an inverted V and a flat about 7 inches apart, that was found to be very flat. its about 7 inches wide and 3 inches deep and 56 inches long with triangular ribbing so it has torsional stiffness. it might weigh 50 pounds.

on top of that i built a sled from a 9" wide 2 foot long piece of granite, gluing plastic pads for friction material and generous lubrication allows it to slide back and forth, with a sheet metal cover on both ends long enough to keep the coolant (garden hose) from washing the oil off the cast iron table.

to the side of the box beam was welded: more scrap square tubing, to that was bolted one of those cheap XY slides you can find on amazon or harbor freight. this is what held a treadmill motor with a grinding stone mounted on it.

due to resonances and vibration problems i couldn't run the stone at the rpm it should have been run at, so i got about a 1:1 ratio for grinding wheel lost compared to metal removal.

but the finish i was able to get, was about as good as what you can get on A36 mystery metal with 240 grit sandpaper.

i built it to grind the top of the T slot table i made for an experimental milling machine. the top of the T is mystery mild steel, the rest of the machine is granite.


what i would recommend if you need a surface grinder but can't get one, is pull everything off your lathe bed and build a sled to ride in the Flats between the inverted Vs. this won't wear out your lathe in any way and its probably flat enough for what you need. the inverted V's will naturally keep oil in the flat.

bolt the bed to a slab of concrete with shims for twist, and to the cement bolt your tower to hold the grinding motor.

when you are done you can put your headstock back on and nothing was damaged.

AJ H said:

Functional surface grinders can be had for $500 or less.....

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If funds are an issue, a collection of hand files can be amassed for even less. Hand filing, a good skill to learn.

I know the purists here will cringe but on occasion I've used a cup wheel on a drill press as a crude surface grinder. Nowhere near as precise or as nice a finish as a real surface grinder but it WILL reduce the thickness of too hard to machine parts and lapping with fine paper on a flat surface improves the finish.

I'm assuming the OP isn't expecting the same results as a large heavy real surface grinder.

Scottl said:

I know the purists here will cringe but on occasion I've used a cup wheel on a drill press as a crude surface grinder. Nowhere near as precise or as nice a finish as a real surface grinder but it WILL reduce the thickness of too hard to machine parts and lapping with fine paper on a flat surface improves the finish.

I'm assuming the OP isn't expecting the same results as a large heavy real surface grinder.

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You think you know someone....really know someone, by reading their post's all these years.....then POW !....

I have to admit a surface grinder would not be the first tool I would choose to make on my own. I suggest operating an actual surface grinder to do a real grinding operation and you will soon realize the problem: moving a large, heavy bed quickly and precisely back and forth.

A tool grinder on the other hand...