Surface grinder, mill, or lathe?

I would go for a good lathe, you can add a milling vice onto the toolpost to use the lathe like a rudimentary mill, but accurately enough for most things you would need to do in knife making. A surface grinder is useful but as mentioned you can lap most things in.
 
Info for the guys wanting to eventually make multi-blade slipjoints.

I have a knife on my bench right now that is a two blade jack. a master clip point blade and secondary pen blade. The pattern I am using, and this is common sizes in vintage slipjoints, has a master blade thickness of .130 and secondary thickness of .080. I am building this knife with CPM154cm. The stock thickness of my so-called 1/8 mill finished CPM154cm is .145 and my 3/32 stock is .103. Without a surface grinder it would be a pain to try and mill this stock to the required thickness, then try and lap a decent finish on it after milling. Some may say, use the stock as-is. Two things, not only is there a fair amount of surface pits that need to be cleaned up anyways, but believe me it makes a difference to me, my customers, and the finished knife if stock is not taken to the correct thicknesses.

I know everyone has a different way of doing things, and everyone is shooting for a different quality level in their knives. However, for making quality slipjoints, especially multi-blade patterns a surface grinder is a big plus in my book.

Besides my 6x26 knee mill I also just picked up a Unimat that I have been using for making bushings and turning pin stock on certain small slipjoints.
 
My wish list is a mill and a lathe, can't you use fly-cutters or end mills to flatten stock with a mill ? I've always wanted a lathe just for the fact you can make wheels with it , isn't it easier to do lathe stuff on a mill then mill stuff on a lathe. Or get a 5-axis CNC machine and let it make knives for you :) .I bought a cheap surface grinder $20 at home depot, a 12x12" granite plate and some sandpaper .
 
I am looking to get a small Sanford sg-2 surface grinder. It comes with a magnetic chuck but is missing the main circuit board. For knife sized objects would a permanent magnet chuck that I can pick off of eBay for fairly cheap price be a viable option as I fear fixing the electro magnetic chuck will be cost prohibitive for a while?
 
Jason,
Chad Cunningham over at Baird had a surface grinder for sale for a while. Not sure if he still has it, but if he does, I'm sure he'd sell it to you.
Jason
 
deloid said:
Page, who clearly knows his machines, mentions the Bridgeport for the mill, what SG would be considered to be the equivalent in quality?

Dean
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I've got a K O Lee, the phone number in aberdeen South Dakota is still the same as it was in 1964.
There's a number of quality S G's out there the trick is getting them at a decent price.
Ken.
 
I've got a Midas 3 in 1 Smithy and it works OK. I couldn't afford more at the time, but it's a decent machine for the size and does the job, you just have to take small cuts when milling or using the lathe. It's a couple steps above most harbor freight mini mills and such as well. I would love to have a larger unit, and if I had it to do over again knowing what I know now I'd probably buy there stand alone mill. That said for folders I use the mill 99% of the time as a precision drill press. I do have a bench and floor model drill press, but neither are as accurate as the mill for drilling and reaming holes. But it does come in handy for slotting guards as well. At one time I used a cup stone to surface grind folder blades, but it was slow going.
 
I have a mill and use it for tons of things other than just knifemaking...

A bridgeport would be very nice, but is arguably overkill for a knife shop and small home shop, particularly if you are just making folders.

duffy99 said:
can't you use fly-cutters or end mills to flatten stock with a mill ?
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Yes, if it's more than 1/8" thick. Thinner stuff ends up curling from the stress introduced by milling. Not sure why, but it's pretty frustrating.
 
You can surface grind with a mill using a cup stone and high speed on the mill. It's still slow though, and it's not a great idea to be putting abrasive powder on your mill. Best is to buy precision ground until you can get a surface grinder. I use my surface grinder(cheap harbor freight model with a belt conversion) all the time from everything from handle material to blade stock.
 
jkf96a said:
Jason,
Chad Cunningham over at Baird had a surface grinder for sale for a while. Not sure if he still has it, but if he does, I'm sure he'd sell it to you.
Jason
Click to expand...

Jason,
I've seen that and thought about it but not sure if I have the space for a large surface grinder. I'm thinking if I get one it might be Travis Wertz's SG attachment for my grinder. I saw one in action at the show in Ft. Worth and was very nice. Best of all it doesn't take up much space.
 
I have a 50$ drill press with vise grips for a handle a mini mill grizzly, and a kmg. Thats all you need to make a folder. Oh and a portaband saw is helpful.

Fancy equipment makes things more fun.

Of the three you mentioned a mill would be the most useful.
 
Will52100 said:
You can surface grind with a mill using a cup stone and high speed on the mill. It's still slow though, and it's not a great idea to be putting abrasive powder on your mill. Best is to buy precision ground until you can get a surface grinder. I use my surface grinder(cheap harbor freight model with a belt conversion) all the time from everything from handle material to blade stock.
Click to expand...

More details on this? I was supposed to get one of the Travis "poor man's" grinder attachment. The real SG's are too pricey for me at this time.
 
I say buy all three but I make a big variety of knives. For slip joints the surface grinder is more important than the mill but I couldn't do without either now. For years I wanted a surface grinder but some how got by without one. The lathe is third on the list.
 
For general machining and fab work, a mill is pretty much always going to win out.

However, for knife work, I use my surface grinder much more. And I'm not making folders right now... Yet darn near every piece of one of my knives goes on the surface grinder at one point or another. :)
 
I've been making folders for close to 20 years. A surface grinder is by far the more useful tool. I don't even need a mill or lathe for folders.

I use a Sherline mini mill to slot guards on fixed blade and little else. All fittings go to the surface grinder though.

I do make some screws and stuff on the lathe though, so it is handy, but by far the least used tool in my shop.
 
Don Hanson III said:
I've been making folders for close to 20 years. A surface grinder is by far the more useful tool. I don't even need a mill or lathe for folders.

I use a Sherline mini mill to slot guards on fixed blade and little else. All fittings go to the surface grinder though.

I do make some screws and stuff on the lathe though, so it is handy, but by far the least used tool in my shop.
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How do you relieve slipjoint liners without a mill? This is something I've been struggling with, and one of the reasons I want a mill.
 
Travis, I've been thinking about a possible solution to that question.

I THINK you could surface grind the spring and blade to the same thickness with your bushing in the blade so that it is also the same thickness as the blade/spring
Then you could grind the blade down another .005 on each side to compensate for .005 washers. You would end up with a blade plus two washers being the same thickness as the bushying and spring. That would give a good tight fit with no blade play and clearance to pivot.

If that is the case then you really wouldn't need a mill as long as your drill press is squared.

I've been thinking about this for a while and would love for someone to correct me if I am wrong so I can move on to think about something else.
 
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