Guindesigns
Well-Known Member
is there a surface grinder for a classic Kmg that doesn't cost over 1000 bucks?
surface grinder question.
- Thread starter Guindesigns
- Start date
EdCaffreyMS
"The Montana Bladesmith"
Not to my knowledge.
I know a lot of folks use those attachments, but frankly I don't care for them.
All of the ones I've worked with, are great for what I call "generally flat" but when it comes providing precision and consistency I've found them to be lacking. IE: Making folders that require precision flats.
Even one of the cheaper 6x12" surface grinders from Harbor Freight, provide more precision then the attachments do. And for about the same money in the used arena.
My advice is.... if you just want "sorta" flat and true, then get a surface grinder attachment. If you want precision flat, and the ability to do it consistently, then get an actual surface grinder...... particularly if the goal is to make folders/folder parts.
I know a lot of folks use those attachments, but frankly I don't care for them.
All of the ones I've worked with, are great for what I call "generally flat" but when it comes providing precision and consistency I've found them to be lacking. IE: Making folders that require precision flats.
Even one of the cheaper 6x12" surface grinders from Harbor Freight, provide more precision then the attachments do. And for about the same money in the used arena.
My advice is.... if you just want "sorta" flat and true, then get a surface grinder attachment. If you want precision flat, and the ability to do it consistently, then get an actual surface grinder...... particularly if the goal is to make folders/folder parts.
Daniel Macina
Well-Known Member
Harbor freight no longer has surface grinders I don’t believe.
bladegrinder
Well-Known Member
If you have the room for a dedicated surface grinder i would go that way. I can't speak for the ones you attach to a grinder because I never used one but like Ed said I think it would be impossible for one of those to hold a candle to a dedicated surface grinder.
used ones are all over ebay and occasionally on craigslist. the thing is some are beat boat anchors so you need to be familiar with them when you go look at one.
I searched for 3-4 years before I found a good deal on a smooth tight Harig 6-12 machine for $850.00
their heavy and kind of tricky to transport and move but once in place and connected to a VFD they are much more accurate than any bolt on gizmo you could attach to your grinder.
My advice, if you've got room, is save your money for a real surface grinder and start looking around.
used ones are all over ebay and occasionally on craigslist. the thing is some are beat boat anchors so you need to be familiar with them when you go look at one.
I searched for 3-4 years before I found a good deal on a smooth tight Harig 6-12 machine for $850.00
their heavy and kind of tricky to transport and move but once in place and connected to a VFD they are much more accurate than any bolt on gizmo you could attach to your grinder.
My advice, if you've got room, is save your money for a real surface grinder and start looking around.
EdCaffreyMS
"The Montana Bladesmith"
Well that's a bummer!
I've not even noticed. I purchased mine WAY back for $999.00 which included shipping. It really doesn't matter whether it's Harbor Freight or any other name brand. All imported 6x12 surface grinders are made in the same barge factory off the coast of China. They only thing different are paint colors, stickers, and sometimes different hand wheels, that are all applied once they reach the US. I did A LOT of research on 6x12 and 6x18 surface grinders.... and learned a great deal. I agree with Steve's input.... Educate yourself, take time, look, and make a wise choice..... you won't regret it.
Daniel Macina
Well-Known Member
Yes it is a bummer! The cheapest new 6x12 I can find now is $3,000Well that's a bummer!
I agree with Steve's input.... Educate yourself, take time, look, and make a wise choice..... you won't regret it.
REK Knives
Well-Known Member
I have a harig 618 dedicated surface grinder but am looking for a belt sg. The stone harig is SLOOOW and I need to speed up my work - even if it's just clean up on the belt then the last pass on the harig.
Also - if you use a metal wheel with the belt sg then you won't get run out at the edges of your piece, which is my main concern.
Also - if you use a metal wheel with the belt sg then you won't get run out at the edges of your piece, which is my main concern.
EdCaffreyMS
"The Montana Bladesmith"
I'm with you on SLOOOW. I used stones on my machine for a week..... and converted it to belts. Some hardcore machinists will argue that a stone is "better"..... but honestly, I can hold within the tolerances I demand for folders with the belts..... plus it increases the versatility of a SG tremendously. AND..... it uses 2x72" belts....so one less thing I have to order/pay for (stone wheels)
If your fabrication skill as decent, it's not difficult to build what you need to convert any SG to belts. The most important thing is getting/making/using a HARD contact wheel. I have a 100 durometer urethane wheel on mine. It came from Bertie Reveld out of South Africa, many moons ago... BUT, if you get with SunRay Corp, and ask them for the "hardest" urethane wheel they can build....it will work. There is also the option of using aluminum or even steel for a contact wheel with a belt conversion (as you obviously know).
Sunray builds wheels to order.... so make sure you have EVERY detail for dimension/measurement for the contact wheel. I've had folks order from Sunray before, based on my recommendation, and then call me raising a fuss because a feature or measurement wasn't what they wanted....and when I asked if they specifically stated they needed whatever it was to Sunray when ordering..... "No, but they should have know that!" NOT! Sunray is a military contractor....and as such, if you do not given them EVERY detail as to what you want....then you just are not going to get it. They're great folks, and make great products..... but don't expect it if you don't order it.
Here's some pics of mine that might give you some ideas for converting your machine....
JeremyBartlett
Well-Known Member
That is exactly what I'm wanting to do Ed...I found an old brown and sharpe #2 surface grinder for $500 and was wondering what my options would be to convert it to belt before I commit to buying it. Not sure how I'm gonna get it in my shop though...since it weights 1200lbs
Smallshop
KNIFE MAKER
Simple and clean Ed...very nice!
Here's the thing with surface grinders...often they are low miles in a machine shop as they will be used to make tooling, etc. unless there is a production job they are doing with it....and you can tell by lookin!
Buy used. I bought my Chevalier 6-18 for $750 20 years ago...with a coolant tank, plenty of wheels, no hydraulic feed (try to get one with as you can walk away and do something else while cleaning off scale! But not a deal breaker...)
Here's the thing with surface grinders...often they are low miles in a machine shop as they will be used to make tooling, etc. unless there is a production job they are doing with it....and you can tell by lookin!
Buy used. I bought my Chevalier 6-18 for $750 20 years ago...with a coolant tank, plenty of wheels, no hydraulic feed (try to get one with as you can walk away and do something else while cleaning off scale! But not a deal breaker...)
EdCaffreyMS
"The Montana Bladesmith"
Keep an eye out Ted! I've sorta/kinda/maybe been looking for a 6x18.... but I'm a picky bugger, in that I'd like to find a "low mileage" one, with a FINE POLE chuck.... and not have to drive to the east coast to get it (would be great if it was in/around MT.)
That's something I failed to mention in my previous post..... for knifemaking, and more to the point.... making folders/folder parts or other smallish parts, you need a GOOD FINE POLE chuck. I had to replace my finish shop door before I knew better, when I used a standard pole chuck. I was hogging with a 50 grit belt.... the chuck lost the part..... tore off that guard on the SG in the pics.... and the part went THROUGH the shop door! GRRRR! Stupid costs! And I was luck it didn't hurt too.
I duct taped up the hole in the shop door, until I could replace it. I have/use an OLD Magna-Lock fine pole on my SG, that I purchase second had off the net, but have always thought this one might be a good value for a fine pole..... https://www.grizzly.com/products/grizzly-6-x-12-dense-magnetic-chuck/t1229 These find pole chucks tend to get pretty spendy in the 6x18 size!
Smallshop
KNIFE MAKER
Will do Ed....
say...on thin small stuff a series of magnetic parallels will make the pull of a coarse chuck fine. some guys super glue them to the chuck and just leave 'em. Once they're glued/ground they are good sacrificial chuck surface. they will collect goobers in the cracks though, so keep 'em a popcicle stick thickness apart so you can get in there and clean...with a popcicle stick. for about $100 you can have enough surface for a pretty large knife.
Amazon link to parallels below
say...on thin small stuff a series of magnetic parallels will make the pull of a coarse chuck fine. some guys super glue them to the chuck and just leave 'em. Once they're glued/ground they are good sacrificial chuck surface. they will collect goobers in the cracks though, so keep 'em a popcicle stick thickness apart so you can get in there and clean...with a popcicle stick. for about $100 you can have enough surface for a pretty large knife.
Amazon link to parallels below
REK Knives
Well-Known Member
Great pics and info Ed!I'm with you on SLOOOW. I used stones on my machine for a week..... and converted it to belts. Some hardcore machinists will argue that a stone is "better"..... but honestly, I can hold within the tolerances I demand for folders with the belts..... plus it increases the versatility of a SG tremendously. AND..... it uses 2x72" belts....so one less thing I have to order/pay for (stone wheels)
If your fabrication skill as decent, it's not difficult to build what you need to convert any SG to belts. The most important thing is getting/making/using a HARD contact wheel. I have a 100 durometer urethane wheel on mine. It came from Bertie Reveld out of South Africa, many moons ago... BUT, if you get with SunRay Corp, and ask them for the "hardest" urethane wheel they can build....it will work. There is also the option of using aluminum or even steel for a contact wheel with a belt conversion (as you obviously know).
Sunray builds wheels to order.... so make sure you have EVERY detail for dimension/measurement for the contact wheel. I've had folks order from Sunray before, based on my recommendation, and then call me raising a fuss because a feature or measurement wasn't what they wanted....and when I asked if they specifically stated they needed whatever it was to Sunray when ordering..... "No, but they should have know that!" NOT! Sunray is a military contractor....and as such, if you do not given them EVERY detail as to what you want....then you just are not going to get it. They're great folks, and make great products..... but don't expect it if you don't order it.
Here's some pics of mine that might give you some ideas for converting your machine....
Regarding Sunray - I purchased a contact wheel (10") from usaknifemaker a while back which was made by Sunray. But I found that it was not true (several thou out of round on the face) and had side to side wobble. Sunray replaced it like 3 times and, while they had superb customer service, they could never get the issue right. I would like to find a machine shop that has the knowledge and capability to make me a steel wheel - I've heard aluminum can groove up or wear with frequent use. But the wheel would need to be true within a couple tenths ideally.
Regarding the belt conversion - I would like to have a dedicated sg for that and not so that with my harig. The reason being is because you would need a vfd on the motor, which means I would need to swap the motor out every time I wanted a stone wheel (and rewire). But it would be fantastic to have a belt converted sg, even over the surface grinder attachment, I agree. Unfortunately I'm limited in space in my shop
REK Knives
Well-Known Member
Also, I got a good import fine pile 6x18 chuck from ebay (brand is Shars) that works great... I just mounted and ground the surface before use.Keep an eye out Ted! I've sorta/kinda/maybe been looking for a 6x18.... but I'm a picky bugger, in that I'd like to find a "low mileage" one, with a FINE POLE chuck.... and not have to drive to the east coast to get it (would be great if it was in/around MT.)
That's something I failed to mention in my previous post..... for knifemaking, and more to the point.... making folders/folder parts or other smallish parts, you need a GOOD FINE POLE chuck. I had to replace my finish shop door before I knew better, when I used a standard pole chuck. I was hogging with a 50 grit belt.... the chuck lost the part..... tore off that guard on the SG in the pics.... and the part went THROUGH the shop door! GRRRR! Stupid costs! And I was luck it didn't hurt too.
I have/use an OLD Magna-Lock fine pole on my SG, that I purchase second had off the net, but have always thought this one might be a good value for a fine pole..... https://www.grizzly.com/products/grizzly-6-x-12-dense-magnetic-chuck/t1229 These find pole chucks tend to get pretty spendy in the 6x18 size!
EdCaffreyMS
"The Montana Bladesmith"
Standard pole chuck spacing is 1/4" or more between the like colored lines, and Fine Pole chucks are 1/8" OR LESS. Grizzly calls the one in the link I posted.... a "Dense Pole" chuck. If I ever need another, I think I'm going to give one of those a whirl.
Hey Ted... I need some educating..... teach me about those parallels... my brain can visualize how'd they be used......especially on very thin, small stuff. I'm obviously missing something, and am thinking this might just turn into a big "DUH!" moment.
Hey Ted... I need some educating..... teach me about those parallels... my brain can visualize how'd they be used......especially on very thin, small stuff. I'm obviously missing something, and am thinking this might just turn into a big "DUH!" moment.
Smallshop
KNIFE MAKER
You lay them down big surface down. The thin divisions bust up the magnetism from big broad waves to finer wave. Still not as good as a fine pole chuck with adjustable pull...but cheap and will tackle most things. You can actually glue enough down to cover the table...or put a row on the outer edge ...just gotta watch the wheel when going between the two chuck heights. Reason guys glue them is to keep grit getting underneath and changing height. Obviously you don't get them hot...if that happen something else went wrong first...lol.
I found a better chuck that I put on my 6-18...I took the other one and mounted some parallels to it and ran it in the cnc mill for thin jobs some shops wouldn't bid on...lol. Haven't used that setup in about 15 years...but it was a money maker. I doubt I could lift it in and out of the machine today...lol.
super glue works good but test with coolant first...some will loosen it up.
I found a better chuck that I put on my 6-18...I took the other one and mounted some parallels to it and ran it in the cnc mill for thin jobs some shops wouldn't bid on...lol. Haven't used that setup in about 15 years...but it was a money maker. I doubt I could lift it in and out of the machine today...lol.
super glue works good but test with coolant first...some will loosen it up.
EdCaffreyMS
"The Montana Bladesmith"
OK... Mr DenseHead has more questions!
So.... you place these on the magchuck...... and are the pieces/parts your grinding get placed on top the parallels? Or, do the parallels just need to be somewhere/strategically on the chuck to change the magnetics of the chuck? Is it obvious yet that I am totally lost?
Smallshop
KNIFE MAKER
The poles on the parallel, Iirc, work best oriented like the chuck itself.(in line with the cross feed). you lay them on the chuck and then dust them with the wheel...mag on of course. Then mag off...lay the parts on...mag back on...and begin grinding. The super glue make a less fussy setup clean-wise...but not absolutely necessary. If your chuck is flat you can take them on and off and just re-dust if you prefer not to glue. I always do a healthy deburr with a skotchbrite wheel before grinding....surface grinder cuts from parallels are miserable...a load of swarf right into the cut...a nice .03 rad or so minimizes that.OK... Mr DenseHead has more questions!
For removing bows/slight warpage from blades with a grinder you have to shim under the bow....otherwise you just suck it down and when the mag is released it springs right back into place. (Ed i know you know this...just stating it for newer guys that might think a surface grinder is a cure all...)