How long to grind a blade?

FlaMtnBkr

FlaMtnBkr

Joined
Oct 20, 2004
Messages
4,704
Hi Everyone,
I am in the process of grinding my first blade. It is 1080 which is 1/8" thick about 1 1/4" wide and about 4" long (from plunge to tip). I am using a craftsman 2x42" sander and attempting a flat grind. At this rate its going to take 3-4 hours to grind it to the point of heat treat and probably another 2 hours after its hardened (I'm assuming...I should know better and multiply that by 2 or 3 since thats how things normally go). Does this sound right? The steel is soft and is really easy to drill, maybe I'm not using a coarse enough belt? I am using what it came with which is either an 80 or 120, should I go coarser? Also, all the production blades I have, have a 'mirco-bevel' where the last 1/16" or so next to the blade has a wider angle (more obtuse). Is this how everyone else makes there blade? Is this angle put on with a stone or is it done on the sander? Sorry for the newbie questions but any help is greatly appreciated!

Thanks, Ryan

PS On a side note, am I the only one that the search function only works about 10% of the time?
 
Hi Ryan,

You should be doing your rough grind with a belt of 40-60 grit. My first grinder was the same grinder you have. The belts that sears sells are cheap crap and way over priced. Try www.supergrit.com give them a call as they carry ceramic belts the size you need and have a good selection of other stuff also.
 
When you use those cheap belts, Throw them away as soon as you feel the belt stop cutting. They are totally worthless as soon as they get dull. If I am not mistaken, www.trugrit.com has them also.
 
I checked out the supergrit site and all I could find in the 2x42" size were aluminum zirconia belts and not ceramic. Are these ok? The ones I am talking about are here.

Any other tips or answers to the other questions? I am assuming from the replies about new belts that this is indeed taking longer than it should? For you makers, how long do you think it would take you to rough at this size blade? Also, what grit should you take it through on the sander before you hand rub it? Thanks again!

Ryan
 
For what its worth, When I start grinding a knife, say a small hunter or bird and trout it normally takes around 45 min to grind before HT. The time after HT all depends on the finish im looking for as I do most my sanding by hand after HT. The final edge your talking about (the cutting edge is put on with my grinder/kmg). Youll be suprised how good belts will make the job easier. Practice and experience will improve you time a lot also.

Good Luck !

Shane
 
The blue zircona work well. In order to get the ceramic you have to call and ask for them. Sometimes they do not have a paticular grit in ceramic. I normally got 60 and 120 in ceramic and 220 and 400 in silicon carbide.
 
I have the same grinder you have and am doing my second blade now, it's taking a while but the 80 grit belt should work pretty well, i have the blue ones from a craftsman store, they are okay, they don't last a real long time, its better than hand filing the whole thing

about the search function, I think 10% is a bit overrated, i am lucky if it works 1%, i don't know what the deal is though, sometimes its better to use google and it finds things in the archives pretty well
 
Thanks for the replies guys!

Now I am going to hijack my own thread...

Does anyone coat the edge and tip with clay during normalization to keep it from getting too hot? While sitting there grinding it popped into my head that it my be a good way to prevent decarborization...just a thought. Thanks!

Ryan
 
I wonder if those who have paid for a membership have easier access to the search function. I never seem to have a problem with it, and tend to readily find what I seek. :confused: Do you folks mean you have trouble accessing the function or difficulty finding information?
 
FlaMtnBkr said:
Hi Everyone,
I am in the process of grinding my first blade. It is 1080 which is 1/8" thick about 1 1/4" wide and about 4" long (from plunge to tip). I am using a craftsman 2x42" sander and attempting a flat grind. At this rate its going to take 3-4 hours to grind it to the point of heat treat and probably another 2 hours after its hardened (I'm assuming...I should know better and multiply that by 2 or 3 since thats how things normally go). Does this sound right? The steel is soft and is really easy to drill, maybe I'm not using a coarse enough belt? I am using what it came with which is either an 80 or 120, should I go coarser? Also, all the production blades I have, have a 'mirco-bevel' where the last 1/16" or so next to the blade has a wider angle (more obtuse). Is this how everyone else makes there blade? Is this angle put on with a stone or is it done on the sander? Sorry for the newbie questions but any help is greatly appreciated!

Thanks, Ryan
Click to expand...

I have a friend that can rough grind the hollows in a 3 1/2" blade in 5 min's
in ATS134 .
on a good day I'm about 10 min's.
clean up after heat treat about two min. then the finish depends on what type finish you want on it.

if you use a fine grit you'll have good control but it'll take forever to grind
that's where practice works for you..
 
Fitzo

I would say its a problem accessing the feature. If I put in something like 'edge quench' it doesnt do anything, but if I put in just 'quench' it will return results...sometimes. I dont know what the deal is.

It sure must be nice to spend 15 minutes grinding out a blade. I guess maybe the knifemaking grinders are worth it. Maybe one day...
 
Ryan, I got a "The page cannot be displayed" message when I tried to search on "edge quench" and "edge +quench" in both cases. I get pages of hits when I simply type in "quench".

Perhaps it doesn't use typical search strings or perhaps it simply does suck.....

Do you get the "advanced search" access when you click on "Search"?
 
I use advanced search and it always works for me.

I have the same frustrating Crasftsman grinder. It's a giant pain in the A to change belts on if you restore the workrest. The Sears belts suck, I too have found TRu-Grit. John and Linda are great folks. I'm lucky in that I travel So Cal for business and can sometimes squeeze in a lunch time stop at Tru-Grit. They often have other cool stuff like mosaic pins and damascus and stuff. Fun stop.

I've taken to just grinding without the rest, which could be hazardous if you get a finger caught between the bottom pulley and the belt. I don't recommend it, but I do it. I've gotten better results grinding freehand like that than using the rest anyway. This grinders other main faults are that the platen sucks and the belt is moving too fast for anything but roughing. All these things are solvable with some time, money and effort. I saw a post from one guy who found a variable speed drive/motor that was a bolt in replacement and it wouldn't be too hard to build a more solid platen to replace the flexi limp noodle platen that they come with. I have several ideas about how to really tweak mine out, but have put the energy into trying to make a 2x72 of my own.

The difference between the 2x42 Craftsman and a real knife grinder was really driven home this past weekend as I got to spend a good deal of Saturday with Steve Ryan in his shop and drool over his Hardcore and Burr King while he was kind enough to give me some pointers and let me look over his shoulder as he worked. It was an awesome time.

My wife is finally back to work and I'm starting to think it's time to throw in the towel and just buy a real knife grinder if I'm going to have any success making knives I'm happy with. Hey wait, it is my birthday in a couple weeks.

Hmmm.....
 
If you have your sander vertical, bolted down, and using 40-50 grit belt it should be completed in 5 - 20 minutes depending on experence level. I still use my 1 x 42 with belts from industrial supplies. buy 12 get 12 free. When they stop biting grab a new one. :)
If you need more help send me a message
 
The time it takes to grind a blade is entirely up to the person doing it. Its possible to knock them out very quickly with the right grinder and technique, but not everyone can do it, or wants to do it that way.
When I first started making knives it took forever to grind them out and do a good job. Now...for knives the size your making, I might take 20 minutes to have it ready for heat treat if I take my time and try to really get things right. If I leaned into it harder and started out with a 36 grit belt instead of 50, I could reduce that time a bunch. Quality might drop off, and that'd be one more kind of belt to buy though. I'm comfortable where I'm at, and the time spent grinding isn't what keeps me from getting caught up.

If I were you, I'd look into some better belts as suggested and just keep practicing. The belts will last longer, saving you money, and cut better making things much less frustrating. Don't get hung up on how long it takes you and how long it takes someone else. The end product is what matters.
 
jmxcpter said:
I use advanced search and it always works for me.
Click to expand...

Then try this for me, please: type in the words edge quench and see how it works for you. I'd be curious to see if your access is different then mine.
 
I have the same problems with the search function, mostly when I type in more than one word. This forum would be a hundred times more useful if I could use more specific searches.
 
You must log in or register to reply here.
Back
Top