# Surface grinder?



## great white (Jul 1, 2022)

I refurb a fair bit of old equipment and do reasonably well with it.. It's mostly a budgetary thing more than a hobby thing. A lot of metal working machines are too expensive for me new, so I usually buy "unloved" stuff and rebuild it. Latest is a 5" B&S mill vice. 

I find myself having a need for a small surface grinder more and more. I'll never need to grind anything much longer than 6-8" at the most.

Used isn't an option around here, they just don't exist. Heck, it's hard to even find a used lathe here, Chinese import or otherwise and if you do happen to find something, people want a stupid amount of money for clapped out machines. Or the other thing that may show up used is HUGE industrial sized machines, which are simply not an option for me, both in cost, mains power, moving it and available shop space. 

New? Well...see above mentioned "budgetary" concerns. Just not an option and my price point (assuming I can even find one I can afford) would be so low the machine would likely be junk anyways.

So I'm thinking I might give making one a try. Looking at the image below, I just about have all of it. So financially it's not a big burden. Space isn't a big concern as I can make it as big or small as I want for the space I have available (which is to say not much space available).

Some googling turned up this image (among others):






Looks to be home built. I have a cast iron xy tslot table gathering dust and the upright on that one looks speciously
close to the Atlas Milling attachment hanging on my pegboard (have a mill , no longer need the attachment). Motors, pulleys, etc I've got hanging around. 

I know it will never be as accurate or as rigid as a purpose built unit, but given the choice of a diy surface grinder or none at all, it worth giving it a try?

For the milling attachment, I'd be using it without modifying it. I'll just build a plinth that the atlas piece will attach to like it does on the Atlas cross slide.

Mag chuck isn't in the cards in the near future either. I've seen a couple DIY permanent magnet one (rare earth) and that might be an option down the road.


If you feel it's not worthwhile or are "agast" at the thought of it, please be kind with your responses and try to be constructive with your criticisms.


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## jwmelvin (Jul 1, 2022)

I wouldn’t think that type of design is unworthy; the column looks a little flexible but that would be okay with light cuts. I have found that even a mist coolant, while helpful and better than dry grinding, is not nearly as good as flood coolant. You mention an x-y table; a grinder needs a fast longitudinal traverse, which a screw drive won’t satisfy.


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## extropic (Jul 1, 2022)

I would say that the machine pictured is setup as a tool and cutter grinder rather than a surface grinder. Not a lot of Z height there to fit a magnetic chuck/workpiece under the wheel. The table Y travel (out) clears the wheel by a lot (leaving room for a work head). Maybe not enough Y travel toward the wheel to cover the table or dress a mag chuck. The table yaw adjustment is typical of T&C grinders. Stiffness of a surface grinder is very important. I think the column in that picture looks way too wimpy along in the X plane.

I think a useable surface grinder can be homebuilt. I think you should find a more appropriate picture/design.

As the result of following a previous project, I have wondered if a common bench grinder could not be used as a motor/spindle for a homemade surface grinder. Maybe upgrade the bearings and balance everything to your best ability. The motor/spindle (MS) could be mounted on a hinge plate arrangement (like a sine plate) and short range (1"?), high resolution Z adjustment made by a screw pivoting the hinge. Simple blocks and plates could be stacked under the hinge plate to make major changes in wheel height. My thinking is that the bench grinder approach breaks the project into two phases. One being the MS I've described and the other phase is the construction of the base and table. A 'better' MS could be added later if desired. Food for thought.


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## great white (Jul 1, 2022)

jwmelvin said:


> I wouldn’t think that type of design is unworthy; the column looks a little flexible but that would be okay with light cuts. I have found that even a mist coolant, while helpful and better than dry grinding, is not nearly as good as flood coolant. You mention an x-y table; a grinder needs a fast longitudinal traverse, which a screw drive won’t satisfy.


Seems an easy fix it to just remove the screw drive and slide by hand?


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## jwmelvin (Jul 1, 2022)

great white said:


> Seems an easy fix it to just remove the screw drive and slide by hand?



I don’t know what the cutting forces are like but I’d want a rack and pinion or belt drive.


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## great white (Jul 1, 2022)

jwmelvin said:


> I don’t know what the cutting forces are like but I’d want a rack and pinion or belt drive.


was actually thinking rack and pinion after I hit "send".....


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## pontiac428 (Jul 1, 2022)

If the price is right, that would make a good start towards a tool and cutter grinder.  Hustle up a work head and a spindexer attachment and you'll be in business.  You will have to clear another spot in your shop for  a surface grinder, but you'll be ahead of the game when it comes to sharpening your tooling.


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## jwmelvin (Jul 1, 2022)

great white said:


> was actually thinking rack and pinion after I hit "send".....



I imagine a cable and pulley would work too. The advantage of that or a belt is less effect transverse to the drive direction. I feel like the rack can impart some notchiness; but it hasn’t really been an issue with my Toolmaker grinder.


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## wrat (Jul 1, 2022)

"Aghast"?
I LOVE it when people repurpose, or upcycle, any kind of machine.  It's where the true ingenuity resides.
Surface grinder.... let's see.....
Goes to and fro?  Check
Stays true to flat/plumb/level?  Check
Spins the wheel?  Check
What's not to like?  
Every grinder has feed limitations.  I just had some grind work done (hired out) and he wouldn't take more than a full thou cut and a half-thou finish.  That was his max on a 6" wide wheel that was over 2 feet in diameter!  On an 8 foot bed grinder!
You'll do great.


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## C-Bag (Jul 2, 2022)

I guarantee you’ll learn a lot. For ease of incorporation I’d go with a cog belt for the x over rack and pinion. It won’t have the inherent problem with play and will be smoother and easier to adjust. I got a complete cog belt setup with a HD treadmill I got for $30 off CL. This was from like a health club and was off the incline drive. Lots of other HD goodies I’m waiting to repurpose.
Another design idea is the little Barker PM. They are typically used as a horizontal mill but I’ve seen them set up as a surface grinder.


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## Ischgl99 (Jul 3, 2022)

This company has plans to build one from scratch if that is something you are capable of.  I don’t know how good the plans are, but for $50, sounds like it would be worth the risk.



			https://www.machineryplans.com/product/acto-250-surface-grinder/


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## Dabbler (Jul 3, 2022)

@great white I wish you were closer to Calgary - I Know of 2 SGs that you could get for cheap cheap.


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## C-Bag (Jul 3, 2022)

Dabbler said:


> @great white I wish you were closer to Calgary - I Know of 2 SGs that you could get for cheap cheap.


Road trip?


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## Dabbler (Jul 3, 2022)

C-Bag said:


> Road trip?


3000 MILES (4700Km) *each way* -- the gas would buy a nice surface grinder by itself.


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## great white (Jul 3, 2022)

Dabbler said:


> @great white I wish you were closer to Calgary - I Know of 2 SGs that you could get for cheap cheap.


just a wee bit of a haul.....might as well be on Vancouver island.....


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## Gnpenning (Jul 3, 2022)

Dabbler said:


> @great white I wish you were closer to Calgary - I Know of 2 SGs that you could get for cheap cheap.


How cheap?


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## Dabbler (Jul 3, 2022)

Harig 900 canukistan bucks with some tooling. the other one nearly free, but not one I'd take.


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## C-Bag (Jul 3, 2022)

Dabbler said:


> 3000 MILES (4700Km) *each way* -- the gas would buy a nice surface grinder by itself.


Oops, thought you were closer


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## Toolmaker51 (Jul 3, 2022)

Doubling up on drive mechanisms, a pure rack and pinion isn't a smooth reciprocating transmission of rotary motion to linear, due backlash in perfecting gear engagement vs table overhang, unless pinion is centered within the table travel. Even so, notchiness can still occur.
A cable wound around a drum, tied to an extension spring is simple zero backlash method; _"good enough" _for many commercial brands. The drum diameter isn't large, 1" is 3.14" travel per revolution, somewhat larger eases regulating feedrate.


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## Gnpenning (Jul 3, 2022)

Dabbler said:


> Harig 900 canukistan bucks with some tooling. the other one nearly free, but not one I'd take.


Have a buddy in Fort McLeod I'll pass it along to.

Thanks.


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## great white (Jul 4, 2022)

Heres a questiin thats probably been answer a at least a dozen times:

Do I really need a surface grinder if I have a vertical mill?

Obviously, no hardened metals on the mill (I only have hss tooling), but can I get acceptable results (for a home shop) using end mills and/or fly cutters?


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## C-Bag (Jul 4, 2022)

great white said:


> Do I really need a surface grinder if I have a vertical mill?


This is such a broad question because of application it is all dependent on the project at hand. Are you talking surface finish, precision, or both? Over how big an area? What kind of machines are you fixing up? 

There is a lot that can be done with a vertical mill and if it’s all about precision hand scraping from there can be as good as it gets. As far as surface finish I was lucky to find an old Atlas shaper that can put out a finish as close to ground as you can get. The place a surface grinder really shines is the ability to use a mag chuck as often a mill vise can’t hold small thin stuff without warping it etc.


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## matthewsx (Jul 4, 2022)

great white said:


> Heres a questiin thats probably been answer a at least a dozen times:
> 
> Do I really need a surface grinder if I have a vertical mill?
> 
> Obviously, no hardened metals on the mill (I only have hss tooling), but can I get acceptable results (for a home shop) using end mills and/or fly cutters?


Building accurate tools is fiendishly difficult. Surface grinders are high precision machines for doing close tolerance work on already hardened parts. 

Unless you have a furnace and need to produce such hardened and accurate parts I think a surface grinder would just be taking up space in your shop.

I just picked up a furnace and will soon be trying my hand at hardening steel but a surface grinder is still far into the future.

As with any tool purchase the first thing to ask is what projects will I do with it.

John


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## extropic (Jul 4, 2022)

great white said:


> Heres a questiin thats probably been answer a at least a dozen times:
> 
> Do I really need a surface grinder if I have a vertical mill?
> 
> Obviously, no hardened metals on the mill (I only have hss tooling), but can I get *acceptable results* (for a home shop) using end mills and/or fly cutters?



The answer to your question depends on your (emphasis on YOUR) definition of "acceptable results".


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## Dabbler (Jul 4, 2022)

great white said:


> Do I really need a surface grinder if I have a vertical mill?


No.  Yes.  well, maybe.  It depends.

If you want to learn new cool skills, go for it.  

But if what you need to do is done very well with your VM, then no.  Definitely not.  Just like the mill, as SG, requires a lot of tooling to do a wide range of tasks.  Tooling costs money.  More than the acquisition price in many cases.  I just bought 200$ worth of hubs for my SG, because I could get them at 1/10 of retail.  My Suburban magnetic sin plate can cost 5000$ new, but I got mine for *very cheap*.  The list goes on.


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