surface grinder for making folders

[Ray Rogers]

One last question. Someone above mentioned that the difference between +- .0001 and +- .0002 is huge for folder work. I'm not one to argue accuracy around here, but is that really going to make a big difference on my 4 inch long liners?

No, that's not huge. Even .001 is not huge. All this talk about surface grinders is mostly applicable to the blade. The rear of the blade needs to be flat, smooth, and parallel from every dimension. The Grizzly and HF surface grinders which many of us use usually will provide .001 variance across that area of the blade and, believe me, your knife will not notice it.

Getting the blade that close on a surface plate can be very challenging and the better the plate is, the easier that may be. For years before I got a surface grinder I used a surface plate from HF that cost about $20. I'm sure it isn't any better than the Enco product but it was adequate for the task and helped me make many successful folders. It's the same as with any other piece of equipment. Drill presses, mills, lathes etc all have some amount of 'slop' in them and yet we still use them to make these highly accurate devices - it's about the maker, not the machine. You'll be able to use whatever surface plate you have.

Like some of these other guys though, I'd sell my soul before I'd let go of my surface grinder now.....

[Kevin Wilkins]

Originally posted by offbyone


One last question. Someone above mentioned that the difference between +- .0001 and +- .0002 is huge for folder work. I'm not one to argue accuracy around here, but is that really going to make a big difference on my 4 inch long liners?

Well, since here in cyberspace it's tough to know who one is talking to, I'd say first, how many years experience and or training as a tool maker or machinist do you have? How many knives have you made? What type of other tools and equipement are at your disposal?

If you are able to achieve flatness to 0.001" then you are in the Ron Lake catagory, and I doubt you'd be asking questions here!

If you are just starting out, you might want to go over to Amazon.com and order the book "Machine Tool Operations" by Krar Oswald and St. Amand. It's an excellent, basic reference to: ta dam! Machine Tool Operations!

[offbyone]

thanks for the book recomendation, and to everyone for all the explanation.

It would be great if someone could validate that my plans for using the surface plate are reasonable:
I mainly plan to use it to ensure things are flat (liners, scales, etc) and (if this is practical) to reduce my blade by the width of my washers, since I plan to cut the spine out of my precision ground bladestock. .

I hope this makes sense and is a feasable approach.

My tools and materials are starting to arrive so I can soon get to work and stop bugging everyone here. Anyway, thanks once again for all the help so far.

(edited to correct stupid reversal)

[Jeff Higgins]

Originally posted by offbyone
It would be great if someone could validate that my plans for using the surface plate are reasonable:
I mainly plan to use it to ensure things are flat (liners, scales, etc) and (if this is practical) to reduce my blade by the width of my washers, since I plan to cut the spine out of my precision ground bladestock.

Offby, I suggest buying Peter Atwood's knifemaking video. He has a very good way to flatten his knifemaking materials, and its just generally a darn good all-around video to watch about how to make a liner-lock folder. (Peter, if you read this - that's a granite counter-top, right?).

I have an SG at my f/t work shop, but for my folders at home I use a 18x24 granite surface plate I bought from Grizzly. It was something like $50 and has served me well. Without getting extremely technical, and like was mentioned previously in this thread, extreme tolerances really aren't needed - just smooth action and attention to detail. My surface plate is as accurate as anyone would ever need to make knives with.

But do get Peter's vid. His method works really well, and the video itself is actually one of the more entertaining ones out there too.

[Brett Schaller]

I have two of the Enco $15 surface plates, and they've worked out great. I waited for one of their "free shipping" specials to order them.

[zerogee]

offbyone - I wasn't implying that 0.0001" versus 0.0002" accuracy in the flatness of the surface plate would affect your folder making. Simply that the claimed accuracy figures can be deceptive (the "precision" equipment industry has far more than it's share of weasel phrases and techniques used to sell you a piece of garbage as a precision device). If you're going to pay for top quality, then you better be sure you're getting it -- otherwise, just get the cheapest you can find and hope it works out for you.

I tend to be obsessive about having and using equipment of true and verified accuracy -- the old engineer coming out in me I guess -- but I can also relax and concentrate on doing my work and know that when things don't work out that it wasn't the equipment that's the problem.

Remember that all the finest examples of folders made by the great old Sheffield cutlers pre-1890 (many still unequaled) never went thru a surface grinder - not even so much as a power drill in most cases.

-- Dwight

[Webster]

Offbyone,
It really depends on what you personally like. I know it's hard to decide, but everyone has there own way of doing things. I simply use a piece of 4x12 steel that has been surface ground. It is 1/2 thick and I mounted a steel bar on the bottom that allows me to mount it in my vise. I then spray 3m 77 and place sand paper on top, it's super flat and the sand paper stays put.

I have a toolmaker friend that allows me to use his surface grinder on the weekends. Without such a friend I would have to buy a surface grinder, it makes life much easier. Good Luck.

Bob Cannon

[Frank Niro]

I notice there has been a lot of conversation about the tools and their accuracy ratings, etc. I have found that in many cases the accurady and skill of the maker has often had a lot more to do with the quality of work done. Frank

[Kevin Wilkins]

If you're using the granite plate with a micrometer and stand or a digital height gauge, the the limit of your accuracy is the flatness of your plate... but why would you do that for folders? If you have a holder for the micrometer, then you can check using that.

If you're spray mounting a piece of sandpaper on the granite and sanding away per hand, then it doesnt make a ####e what you use. You can use a plate of glass, a piece of granite from tile service or a flat ground steel plate. The thickness of your glue and the elasticity of the paper and glue render a machinist granite surface mute.

[Webster]

As I said before, you will find out what you like to use and everyone does it a little different. The bottom line is, the way I do things works for me, if it doesn,t work for you that's ok( I am simply sharing some of my methods). It's is nice to have options and ideas from other makers. My folders are precision made and they sell.
Good luck.

Bob Cannon

[offbyone]

Anyway, so i ordered the $15 9x12 Grade B surface plate. Perhaps I could have used something cheaper (?) like a piece of glass since my main use of it will be for sanding, however I do like having a surface that is (supposedly) a certain level of flatness and I have no doubt that I will find it of use for other applications.

I also learned a whole lot from this thread. Hopefully someday I'll get a surface grinder but for now I will work without it. While some of you find them indispensable, I am confident that I can get by with my simple piece of granite.