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tronica
01-05-2012, 12:23 PM
Im pondering building the surface grinder from the May/June HSM 06. One question i have is the author doesn't specify motor requirments. Does anyone have any insight on the requirements for the motor? Thanks

J Tiers
01-05-2012, 11:11 PM
Hah.......

No particular info on motor OR bearings was findable on a quick but reasonably careful skim through all 3 installments.....

Since the motor is apparently directly connected to the spindle, with the motor shaft located concentrically within the spindle and set-screw attached, you would want a low vibration motor. If it had some form of compliant coupling, one might get away with more vibration. I don't know that I am "in love with" that drive system.

Some information seems to have been left out, or else it is buried in the text and I missed it.... no "see text" note in the bill of material though. bearings don't seem to be specified, and the motor is barely mentioned other than dimensions in installment 2.

Looks like a lot of work to build, if you expect to get decent performance out of it..... makes one wonder if maybe the ones Griz etc sell can be that bad.... or that much more expensive!

tronica
01-07-2012, 09:07 AM
Thanks for the reply, yeah i guess im mainly after HP, rpm, i know just by the design it physically can't be to big.

PixMan
01-07-2012, 09:34 AM
Just out of curiosity how much does it cost to build one, assuming home shop time being free? I see used manual surface grinders showing up on Craigslist around here for anywhere between a low of about $300 up to $1200.

Occasionally there's a more expensive one, but most are fairly cheap. Sure, some are really worn out pieces of scrap, but many ragged-looking ones can still grind pretty nice.

tronica
01-07-2012, 10:06 AM
I haven't really figured cost, as I've come up with everything i need with scrap and stuff i have lying around.

Lew Hartswick
01-07-2012, 10:12 AM
It seems to me a "home built SURFACE GRINDER" is on the order of
a self taught brain or heart surgeon. :-)
...lew...

strokersix
01-07-2012, 10:36 AM
Well it depends on your objectives.

If one of your objectives is to learn something building a challenging project then building your own surface grinder might make perfect sense.

I do lots of things that might not make sense in terms of time or dollars. For example, decking an inline six cylinder block on an 8x36 mill. Many would say that's not possible or a bad idea but I've done it quite successfully.

A project I've been considering for years is building a line boring setup to fix main bores on 454 chevy blocks. Makes very little sense to save damaged OEM 454 blocks from time standpoint but perfect sense in terms of learning and satisfaction.

Kind of like the guys at car shows that pay to have their cars built and like to sit around and BS. Nothing wrong with that, just not for me. The project itself and figuring out how to do everything myself is what I enjoy. Don't have much use for BS.

J Tiers
01-07-2012, 10:38 AM
Oh, a person COULD build a nice one.... especially if they had access to a good surface grinder........

Or if they were proficient at scraping ans had a well-equipped shop.

What, you don't suppose Lane could build a good one? Yah.....;)


The real question is what way gets a better grinder? (Unless you like building machines, of course.)

1) build from scratch

2) buy used and refurbish.

3) Buy griz etc....

I'd bet that 2 or 3 is going to win..... "2" is like "1", except that you get all the parts and only have to do the finishing (you "add the accuracy")

Doing "3" means you plug in and use. All teh other stuff is done.

Mcgyver
01-07-2012, 01:36 PM
Im pondering building the surface grinder from the May/June HSM 06. One question i have is the author doesn't specify motor requirments. Does anyone have any insight on the requirements for the motor? Thanks

Even if belt driven, the motor still should be balanced. Surface finish is usually considered important with surface grinding and you will have to work hard to chase out vibration from every source for good to great finishes.

As to pondering, there is zero doubt in my mind this is just not worth it. DIY surface grinder ideas might have been compelling when the small Norton was 8 or 10 grand, but if they're $1000 with the chuck why bother? Work evenings at McDonalds if you don't have the 1000....and you'll get a better grinder in 1/10 the time. Cripes even at 2000 that probably holds true.

look at how massive the small Norton is its just sufficient to get good results. And it has a super smooth roller table, large precision spindle, precise down feed mechanism etc etc.

dp
01-07-2012, 02:30 PM
I hesitate to bring this up again because of the derisive response it received the first time round by the narrower minded, but I modified slightly a radial arm saw to function as a "poor man's surface grinder". My intention was to improve on the finish I was getting from a belt sander, not to create precision dimensioned parts with a surface flat to an angstrom. It works very well, in fact. I simply placed an x-y table on the RAS, put a balanced grinding wheel on the motor shaft, and I had two options to grind: Using the x-y table, motorized with an electric drill, or using the RAS over-arm to rough things in. Despite all the crap I got for it, it works exceptionally well, and far better than a belt sander for non-precision final finish work. Fast, too, and I didn't have to give up any rare floor space as I already have two RAS in the shop.

I also used that same RAS to create a surface planer for wood working using a belt sander belt and that works so well I should patent it. I wanted a way to mill wood to make ukulele sound boards, sides, and backs. RASs are like shapers - no end to the ways they can be used.

tronica
01-07-2012, 02:49 PM
Thanks dp for the reply, the thought of using a radial arm has crossed my mind a few times.

alanganes
01-07-2012, 03:12 PM
Im pondering building the surface grinder from the May/June HSM 06. One question i have is the author doesn't specify motor requirments. Does anyone have any insight on the requirements for the motor? Thanks

I do not recall the details of the grinder in that article, but if you are interested in building a grinder, and are interested, I may have spindle you could base it on. This is a "real" highspeed grinder spindle (rated for ~10K rpm, IIRC) that I picked up some;place along the way. I even have the filter/mist lube unit that goes with it. You don't say where you are located, but if you by some chance are anywhere in the vicinity of NE Massachusetts (USA) you can have the thing. It is currently in the "toss-to-scrap" pile as I am sick of tripping over it. A pic and more info here:
http://smg.photobucket.com/albums/v479/alanganes/for%20sale/kurt/?action=view&current=IMG_3857.jpg

Free to take if you care to pick it up. It's heavy and somewhat large and would be a bit pricey to ship, I suspect.

taydin
01-07-2012, 03:48 PM
I am following this topic with great interest!

Here is a reason for wanting to build a surface grinder instead of buying one. In my country, you can't buy small shop type surface grinders. The cheapest to be found is more than $10,000 and weighs more than 4 tons.

One question about the motor coupling. Instead of trying to get a low vibration motor, isn't it easier to place the shaft into precision bearings and drive it with a belt? The thinking is that the belt will mostly absorb the motor vibrations.

tronica
01-07-2012, 04:00 PM
Thanks alan for the offer, but im in Missouri, that might be a bit of a drive :P, But i do appreciate the offer. And thanks for the reply.

tdmidget
01-08-2012, 12:52 AM
I do not recall the details of the grinder in that article, but if you are interested in building a grinder, and are interested, I may have spindle you could base it on. This is a "real" highspeed grinder spindle (rated for ~10K rpm, IIRC) that I picked up some;place along the way. I even have the filter/mist lube unit that goes with it. You don't say where you are located, but if you by some chance are anywhere in the vicinity of NE Massachusetts (USA) you can have the thing. It is currently in the "toss-to-scrap" pile as I am sick of tripping over it. A pic and more info here:
http://smg.photobucket.com/albums/v479/alanganes/for%20sale/kurt/?action=view&current=IMG_3857.jpg

Free to take if you care to pick it up. It's heavy and somewhat large and would be a bit pricey to ship, I suspect.
Surface grinders do not turn 10,000 RPM. This could only be for an ID grinder.

jackary
01-08-2012, 07:04 AM
Here is one I made.
http://i107.photobucket.com/albums/m287/jackary2003/th_P1010546-1.jpg (http://s107.photobucket.com/albums/m287/jackary2003/?action=view&current=P1010546-1.jpg)

http://i107.photobucket.com/albums/m287/jackary2003/th_P1010545.jpg (http://s107.photobucket.com/albums/m287/jackary2003/?action=view&current=P1010545.jpg)

Alan

Peter N
01-08-2012, 09:15 AM
This chap made one, and very interesting it was too:
http://www.youtube.com/watch?v=3K3Vo2s-uYk&feature=channel


We also had quit an 'interesting' discussion about it on here some 4 years ago :D
http://bbs.homeshopmachinist.net/showthread.php?t=31710

justanengineer
01-08-2012, 09:20 AM
[QUOTE=J
The real question is what way gets a better grinder? (Unless you like building machines, of course.)

1) build from scratch

2) buy used and refurbish.

3) Buy griz etc....

[/QUOTE]

Your point that I deleted is very well taken, but you forgot

4. Buy a used machine that you dont need to refurbish.

Ive seen many shops that have had really nice grinders which were rarely used but well maintained and accurate for that occasional job.

I also recently placed a "joke" bid on a Doall 618, one of the best small grinders IMHO, that had been professionally rebuilt/painted for the military yet was actually never stored outside. Governmentliquidation.com sold it for ~$180 in what could be considered perfect condition. I kicked myself thoroughly when I realized I missed the closing of that auction by a few hours.

sasquatch
01-08-2012, 09:27 AM
Impressive projects, thanks for posting those!!

alanganes
01-08-2012, 10:01 AM
Surface grinders do not turn 10,00 RPM. This could only be for an ID grinder.

True enough, but of course it does not "have" to be spun that fast, that is just what it is rated for. This was likely used for a diamond dicing saw used cutting glass or silicon wafers. The wheel end is 1.25" diameter so would be a bit large for an ID grinder. I only tossed the offer out as it would offer someone building a grinder of any sort a set of very nice bearings as a base for starting a build. Just a thought.

J Tiers
01-08-2012, 10:26 AM
Your point that I deleted is very well taken, but you forgot

4. Buy a used machine that you dont need to refurbish.


Not applicable.....:D

If it was still good they would keep using it!

There is ALWAYS some problem, the key is knowing if it's a big one or a little one.

PixMan
01-08-2012, 11:18 AM
Commercial shops don't always sell off machines just because they've worn it out. Probably more-often it's a case of they need the room and don't use it much, or needed a bigger/more-productive machine.

jugs
01-08-2012, 11:26 AM
Not applicable.....:D

If it was still good they would keep using it!

There is ALWAYS some problem, the key is knowing if it's a big one or a little one.

Not true,
I've seen plenty of perfect machines go for peanuts because some idiot in a suit made a dumb decision

J Tiers
01-08-2012, 12:34 PM
Not true,
I've seen plenty of perfect machines go for peanuts because some idiot in a suit made a dumb decision

hah....

Suits SCRAP good unused tools and machines, because it is easier to take the tax writeoff than try to sell them.

Mebbe YOU got a goodie from a corporate source..... I'd bet a good deal of money that out of 100 available items "out there", maybe 2 or 3 of them at most fit your description..... the rest have "something" wrong with them.

BTW, "suits" are idiots, in general.... agree 100% with that as regards business decisions. As regards decisions on how THEY are gonna run off with all the money, well, they do quite a bit better at that part.


Commercial shops don't always sell off machines just because they've worn it out. Probably more-often it's a case of they need the room and don't use it much, or needed a bigger/more-productive machine.

Yeah, but WHICH one they get rid of is usually the one that works the worst..... they don't usually keep worn-out and sell the best.