Help in using a belt grinder

Alarion

Alarion

Joined
Nov 26, 2001
Messages
1,375
My work of transforming pounds over pounds of fine steel into useless dust continues...
Ok, I'm exaggerating... I just tried to grind two knives: one started as a tanto-style about 8" long and is now miniature-size (and still wrong). The other is a bit better, but has the edge mis-centered and the spine all wrong, perfect on one side, wobbly and overground on the other.
I know it's not much as an experience, but I feel I have a definite problem and that I can't progress with it.
I can't get a decent hollow grind. It seems I can't maintain straight pluge cuts or a constant height of the spine...
I followed Hrisoulas' advices without any result. In the end It seems to me that I have a problem with the pressure I exert against the wheel. I'm using a 10" wheel, 2.5" wide.
I start with a 80 grit, then go to 100, then 200 and 400.
I try to get the shape as good as possible with the 80 and then to refine it with the finer grits, but I always mess everything up.
When you grind do you press firmly the steel against the wheel?
Do you keep a very light touch, the steel lightly touching the belt?
Does pressure vary with grit?
Any trick to have more constant, true to the belt pressure on the blade?
Please help me... don't let me destroy other fine steel...
I warn you! I have hostages! I have two bars of syntherized ATS34! I'll grind them! I'll do it!!! :D :p :D
Thanks for any tips. :)
 
sharp belts, the best possilbe, the finer the grit the slower the speed for the best cutting, i went throught alot more than two bars before i started to feel the touch. also buy the best belts possilbe.there are no bargain belts that cut worth a sh@#.
 
Laurence said it all pretty much. One thing about pressure though. Most new builders put too much pressure on the belt. If the belt stops cutting, replace it. The rest of it is feel and the only way you will develope it is by grinding. I would suggest getting about 20 feet to low carbon 1/4 X 2" steel. Create some dust. Otherwise you are going to ruin a lot of good steel getting the hang of it.

It's impossible to tell you how to keep your grinds even. Every knife maker I know does it differently. Again, practise and develope your own style. After you've done that you will start to pick up on the little tricks that make it easier.
 
Hi,
Mark Center with 2 lines. Run VS at 1/2 -3/4 speed until you get a better feel for it. Bevel the edge at 45degree angle. Keep those elbows against your sides! Rock body from side to side. Start the actual grind with mild to moderate pressure. When first groove started, widen it gradually with each pass. Keep those elbows against your sides! Just touch but don't obliterate your center mark. Smile, you are about to A. make a knife. B. burn your fingers. C. sand your knuckles D. all the above.
Great fun, Enjoy, Ken
PS: Until you get used to it, Keep those elbows tucked into your sides!!!
 
You will need several things to do the grind properly.First,have a drink.Second, have another drink.Third, get the blood of a young white hen.Fourth, take foot a hen and dip in blood.Fifth,sling blood at grinder in an x pattern while hopping on one foot while singing "girls just want to have fun".Repeat this process before grinding each time until you improve or are arrested and sent to the boobie hatch.:D


Or you can do what Peter said and just practice with some scrap steel. The only problem though is that with the mild steel you will end up with an absolutely perfect grind and be mad that you didnt use good steel.

Mark
 
I think that thing about keeping your elbows stuck to your sides is pretty valuable indeed...
I'll grind and grind :)
Sooner or later I'll get a good knife :D
I think also some sacrifice to the steel-grinder gods will be useful, even if I won't go so far to kill hens...I think I'll stop to the "have a drink" step :D
 
Alarion, what I do is start with 36 grit, grind fairly lightly (elbows tucked like Ken said) until I establish the 'groove' and then I lean into it to remove most of the metal. Then I shift to 60-120-220-400 with lighter pressure (generally) as the grit gets finer. I also slow down the variable speed moving to finer grits. Leaning into a 400 grit is silly; do your work with the larger grits and refine the finish with the finer. Fresh belts give control, shiny belts cause trouble. Just my 2c, I'm still learning.

I spend at least $15-20 per knife on belts. At the end of the year I'll do a two-year average of belt usage to determine how many belts I use per overall inch of knife and offer that for comparison here; I'd sure like to hear ways to use fewer belts.

Dave
 
Sounds like you need to develop an "organic" tool rest like Darrel and I have:)
Use your body, not your arms, for control and movement.
 
I don't know if this will help, but I take masking tape and tape off the area of the blade that I don't want to grind into. Of course the tape will not keep you from grinding in those areas, but it will give you a good guide for your lines.

-chris
 
As I am a rank beginner myself and still trying to learn all this stuff myself I have just one piece of advice to give. Comfort. the more comfortable position your body is in the steadier you will be. I'm thinking of making a combination barkalounger-grinder for this very reason.:p Well ok maybe not quite that far, but still either a good barstool if working at standing hight or a decent chair on casters so you can just push yourself around your shop. Well that's my .5 cents
 
Alarion, On your first post you say you are using a 10 x 2.5 inch wheel , i assume you are using 2.5 inch belts? Nobody has mention grinding on wood it cheap,and shows up mistakes fast. When i started i marked my intended grind profile on the side of the blade and worked my grinds up to these lines.good luck.
 
So Kit, with that organic tool rest of yours how do you grind with your back to the grinder? Darrel wears his in front, but yours always seems to be strapped on backwards... :)

I think one of the biggest problems people have who are inclined to say "if that Hossom idiot can do it so can I" (which btw is true), is that the Hossom idiot took a very long time wasting a lot of steel before he made a decent knife. You'll also need to waste some steel but I'm sure you'll learn it a lot faster than I did.

I can't emphasize enough that starting with a small, simple blade (maybe 4" max), and grinding that same blade time after time until you get it pretty close to right twice in row, will get you there a lot faster than if you try for the ultimate tactical bowie, then a hawksbill, oh and how about a tanto, then a whatever. Doing that doesn't allow your hands to become educated at any task. I recommend profiling the same simple 4" blade three times, and grinding all of them together at each grit, randomizing the order with each belt change. What will likely happen is you will trash one right away, have one that you will probably trash next week because you've gotten better, and the third one will look pretty good. At every belt change you are reeducating your hands at the task and feel of the belt, so the first blade you grind at each step is always shakier than the other two. Once you do that simple 4" blade well enough to put a sh*t eating grin on your face you're ready to try something else, but do three of the next one too. Steel is cheap, your first nicely ground blade is priceless.

We all went through the same frustrations and sense that there must be some magic secret that would manifest itself if we just asked the right person the right question. There are no secrets, just practice. And remember this, if that Hossom idiot can do it, anyone can. :)
 
How do you get to carnigie hall?

When starting a hollow grind groove to follow, I have to lock my arms to my sides and swivel more from the hips than anything. After that, I can stroke the groove more using my arms but they are still held quite closely to my sides. I start with a 36, 50 or 60 grit, depending on what I have but almost always it is roughed out with a 36 or 50. Use lot's of dykem bluing with scribed lines to follow and grind to. I measure the grind lines on both sides to the spine often to keep them the same. Mentally insist that each grit has to have straight lines where you want them. If you wait to a higher grit to straighten them out, it's a royal PITA and slows everything down. Use fresh belts for each knife. It will be cheaper than a divorce when you come in all pissed off after a grinding session.

When straightening a grind line, I'll move the blade across the wheel much quicker than when I'm trying to move the line, almost 2 to 3 times as fast. I'll move it back and forth quickly with lighter pressure.

My 8" wheel groove is much easier to follow than my 14" wheel groove.

Have fun. Wait till you start stressing out about your plunge cuts...
 
Originally posted by Alarion
perfect on one side, wobbly and
overground on the other.
Click to expand...

All the other advice here is great and should help you
but
I see you answered your own question here.
It helps very much to be ambidextrous.
if your not you will have to work on
it a lot, I think everyone has a
better side to do that seems easier
to do. you'll need to learn to
use both sides the same.
once you get a grove started at about 80 grit or even
100 grit
go to a higher grit and slow
down, spend the time straightening your
lines out light cuts
putting pressure where you need it just
like the good side your doing,
then when you get good at it then go to
_60 grit and put out some blades
 
Whats this hollow grind thing you guys keep talking about? :D I cant give you any advice about it cause I flat grind everything but I needed to needle the hollow grinders out there :)
 
Hey Art try it
it's like the frosting on the cake.:D Sweeet
I flat grind too but Hollowing just fills a place in my heart.:)
 
My mentor is a guild member.
He cut out half a dozen pieces of wood in the shape of various blades gave me a new fresh belt about 45 or 60 gritt and away I went. You vae to be light with wood to feel the bevel as you go it was a good lesson on feel. I am still learning but all the locals I have spoken too all agree one side is easier in the begining it is just practice

Try writting with your opposite hand. Your dominant side will always be easier to sart with. I now find it easier to hollow than flat grind.

stick with it.
 
Thanks evrybody, guys!
It's a helluva lot of fine advice I got here!
Well, now I suppose it's just practice, practice, and, for when I'm tired with practice, some practice just to make a change :D
 
Jerry,
You are gonna have to explain that one about the tool rest. It went right over my head:(
 
"...will get you there a lot faster than if you try for the ultimate tactical bowie, then a hawksbill, oh and how about a tanto, then a whatever"

I resemble that remark!! :D :p

"Smile, you are about to A. make a knife. B. burn your fingers. C. sand your knuckles D. all the above"

I love that! :D I want it as my sig line please :)
 
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