View Full Version : Not bad for a evenings work
Roving Rich
24-08-2004, 09:15
Inspired by the meetup and all the wonderful knives on show, and Peters (Espy) forging demo. I decided to attack the piece of 01 steel i bought a while ago and make myself a knife. So last night after work i got the hacksaw out and set to :
http://www.bushcraftuk.net/photopost/data/500/152KNIFEBLANK.jpg
http://www.bushcraftuk.net/photopost/data/500/152Knifeblank2.jpg
A few flat spots but basically its there shape wise.
Got to put a bevel on it some how, sounds like i score a centre line to work to, but no idea how I set 30 degrees ?
For an interrupted evenings work I'm well chuffed :-P
Thanks for the inspiration guys
Rich
Use trig, Rich. Sorry...
Maths break:
You know the width of the steel. Divide it by 2. Call it "o".
You know the angle you want as an included angle - 15 degrees per side (for 30 degrees total).
You want to know the height of the line to file to from the edge - call it "a"
You may or may not recall that the tangent of an angle is equal to the opposite/the adjacent? Therefore, to calculate the height of the grind, you use
a=o/tan 15
So for 4mm steel => o=2; you want a grind height of 7.5ish mm. Take the grind height to about 11mm, and you have an included angle of about 20 degrees (and so on and so forth).
Alternatively, just get it hot and hit it :D
Oh yes - and I like to use masking tape to cover the areas I don't want to file. You'll scuff that before you do in the steel, but replace it as soon as you do scuff it (unless of course, you're up against some sort of insane self-imposed deadline...)
HTH
Triganom . triganam .... . oh bugger ... use the force :wink: .
are you wanting 30 degrees either side? . seems a bit steep ...half the thickness of the steel multiplied by 3 away from the edge,
or inclusive; full thickness of the steel x 3 away from the edge and take the grind to the middle, possibly a bit thin
single side bevel; full thickness x 3 on one side only take the grind to the opposite side of the edge
Right angle is 90 so 1 over 3 gives you 30 degrees
oh and a nice graceful shape Rich :biggthump
I like the shape a lot. If I ever get round to getting my design done it will be pritty much that shape with though a bit bigger as a like chubby handles
well done rich, it looks like its coming along nicley
Buckshot
24-08-2004, 11:49
Very prity rich
Cheers
Mark
If you can get such a great shape, I'm sure you will grind in that edge more than perfect.
Nice work!
-Emile
bushwacker bob
24-08-2004, 17:49
At this point Rich I ought to warn you that you have now embarked on a very time consuming and compulsive hobby. :super:
Squidders
24-08-2004, 20:21
It looks like a really nice shape and size. It'd be great if you could run a series of your progress so we can see it develop and your thoughts and decisions.
On a side note, in a few knives time, I may be badgering you for a commission :naughty:
The General
24-08-2004, 21:51
Nice! Give me a call if you want an edge on that! :wink:
had another peek, Rich . and been wondering what kind of transition you are thinking of using from ricasso to bevel ... the flow of the blade looks like it would be good with a nice radiused transition
If you make the width of the bevel twice the thickness of the blade then you will have an angle of 30deg, eg for 5m thick steel the bevel should be 10mm wide. 30deg will give you a strong and sharp skandi grind, although you can make this angle smaller if you wish to improve cutting performance at the expense of weakening the blade.
Pay attention to What Chris said ... ignore completely what i said ... my maths sucks ..... that's why I use the force :wink: .. if you asked me what any of the angles are on my knives ... i wouldn't have a clue .. and would probably reply ... the "right" angle :o):
Roving Rich
25-08-2004, 15:57
Thanks guys i will try and keep you posted on progress.
Thats a great tip on the bevel angle Narsil, makes life a lot easier.
The intention is to make 2 identical blades and put a different bevel on them to compare how they work and which i prefer.
General - They can certainly come your way for sharpening and your opinion. After all you were one of the folks that inspired me to make em at the meetup. - Long way off yet tho.
Mushi - I dunno what the ricasso is but a radius sounds good ? :oops: is it like the choil
Cheers
Rich
Rich ... go in to British Blades and ask Harvey :o):
ok joking aside, the ricasso is the flat of the blade before the bevel begins, a radiused transition looks like this, top one, obviously ;)
http://www.britishblades.com/forums/attachment.php?attachmentid=87 3
rounded where it begins the bevel instead of a straight plunge. As your edge begins with a rounded shape, I feel that a radiused transition would compliment it
Roving Rich
25-08-2004, 17:37
Right thought that that might be what you ment, i'll see what i can do :biggthump
Rich
Roving Rich
26-08-2004, 11:40
Nearrrrrly identical...
http://img.photobucket.com/albums/v285/ROVINGRICH2/knifeBlanks3JPG.jpg
Keep the faith brothers and sisters the force is strong in this one.
This is the use the force grind as prescibed by Mushi 1 Kanobi, the force being bench grinder and file, a little to much force me finks. But all will be well
It did prove that idon't want to do the precise single bevel that way, and how nice those becels in Mushi's pic are. :roll:
Onwards
Rich
Technique;
OK this takes a bit of practice and a little help from a simple jig to set the bevel angle.
but the transition is formed by careful adjustment of the tracking on my belt grinder so that the belt is running about 1/4 " off the platen and plunging the blade down where the transition is, right on that unsupported bit of belt, then dragging through to the point .. finishing was done with a piece of copper pipe or dowel wrapped in silicon carbide paper going progressively down in grit, although the latest technique now uses a bit of flat oak board with a radius routed on one side.
Roving Rich
26-08-2004, 12:02
:yikes: what have i gotten into
Rich
a rather addictive and time consuming hobby :o):
a rather addictive and time consuming hobby :o):
NO
A VERY addictive and time consuming hobby :wink:
Roving Rich
26-08-2004, 12:21
not another one !
So i better set up the belt sander, sounds a bit tricky to me.
Would a nice slow watercooled grind stone work ?
And should i drill the handle now before hardening?
better buy some new files aswell....
Rich
I'd definitely recommend drilling before hardening .. some tangs are very difficult to anneal again after hardening :naughty:
what kind of belt sander have you got?
I rarely use files, setting shoulders and detailed work perhaps, on the whole I prefer to use Wet'n'Dry wrapped around pieces of hard wood
I'd definitely recommend drilling before hardening .. some tangs are very difficult to anneal again after hardening :naughty:
Especially tangs attached to knives made with the help of a couple of "glamorous assistants" (whose names escape me...)
I'd definitely recommend drilling before hardening .. some tangs are very difficult to anneal again after hardening :naughty:
I should have heated the tongs to red heat too - use them as additional thermal mass for slower cooling.
Live & learn.
Roving Rich
30-08-2004, 12:17
Onwards -
http://img.photobucket.com/albums/v285/ROVINGRICH2/DSC_0974.jpg
not 100% happy with em, a bit more fine shaping to do - does it ever end ?
lost the tip off the single bevel, over ground one side over the centre line,then lost the tip grinding the other bevel. The convex grind was exactly that and looked real nice :-) till i reground/filed it to get a sharp edge for a fire steel :roll:
still, they are gettin there.
So how do i go about hardening them ? :o):
Rich
WOW they are really coming along fast
definitely getting there ..... you'll find the fine shaping to be the most tedious .. but I find going in to a trance like state helps :shock:
So how do i go about hardening them ? :o):
well i notice you've been hovering around BB . there's lots of info if you want to do it yourself
you can go the charcoal way ... you don't need a grand piano .. hairdryer will do ... or a plumbers torch inside an insulated steel tube ... get the O1 to just over non magnetic (780 - 820 Celsius) bring it out and let it cool down a bit in air, repeat 2 - 3 times . then get to non magnetic again and quench in some warm veg oil or variant.
this gives a bit more info
http://www.ghcook.com/crp01new.htm
alternatively ... send it to one of us at BB and we can do it for you :wink: .. might even put a hamon on it :lol:
Pretty much anything will do for an air source. I've been playing with using an airbed pump over the weekend - gives a small draught, but perfectly adequate. Vacuum cleaners (eg shop vacs) with an exhaust work well too.
Or you could build a grand piano and pretend it is a box bellows :D
Roving Rich
31-08-2004, 15:16
so i need to build a hammond ? wasn't that the one with the spinning speaker.....
oh a hamon ? wots one of them then ? does it come in a box ?
Built a forge when i were a lad, used the bottom of a 40 gallon drum, and a hoover. Fun, but a bit overkill ? how does this pipe or firebrick and a blowtorch work then, surely i cant just lay the blade in on the floor....
Urrr that link has really confused me, can anyone translate ?
And how did you know i'd been a BB ? :shock: is somebody watching me ? tis conspiricy tis true tis true...... :spider:
Rich
The 1 brick forge is nice and easy:
Take a soft firebrick. Bore a hole end to end. Bore another hole in the side to stick a blowtorch into. Keep the blade moving back & forth to even out the heat.
that wavy line with speckles along the edge is a hamon
http://forums.dfoggknives.com/iB_html/uploads/post-2-41069-diddy_hamon.jpg
it's created by insulating part of the blade from the sudden temperature change in quenching so you have a hard edge but softer body of the blade in the traditional japanese forging method .. it supposedly gives the blade the shock resisting properties of softer steel with the hard edge for good prolonged cutting with edge retention ..... no it doesn't come in a box :nana: :o):
fundementally.. get the blade hot a couple of times and let it air cool .. when I say hot . almost red hot ... around non magnetic ..... then get it up to non magnetic and catch it right at the point it changes, slip it in the heat for another 5 seconds to be sure ..... and then take it out and plunge it in the oil till it is hand warm .. then run to your oven and put it in the oven at 200 degrees C for an hour ... you now have a hardened and tempered blade
and your name was in the list at the bottom of the page on BB, not exactly spying, just observant :nana:
Roving Rich
31-08-2004, 17:22
:o): :o): :o):
Sounds straight forward, can't wait :hyper:
How do i find the point of change, put it next to a compass or try and pick it up with a magnet ?
I suppose there is no need to harden the tang so i can hold that to pass it in and out of the heat....
I caught an episode of "ultimate weapons" at the weekend on satellite, all about the Samurai Sword, showing how they make em, how they put the Hamon on with using a thin layer of clay. They were using the box bellows or grand piano, exactly like Peter had at the meetup. But not in the sand , on the floor in one of those Japanese paper houses !!! :shock:
Those bellows are great. propel air in both pumping directions. That is how the Chinese has Steel 1500 Years before we did in the west ! :notworthy
I've still got some more work to do on the knives before hardening - thats what BB does :shock: Kind of puts my amateur efforts to shame.
Thanks for your advice
Rich
That is how the Chinese has Steel 1500 Years before we did in the west !
Actually, the Saxons had steel 2000 years ago - they just couldn't make it in any quantity, which made it insanely expensive. So steel production was left alone untill the middle ages, when advances in smelting technology made it a viable economic option.
The General
01-09-2004, 03:48
Historically the Welsh it seems, were working with Steel before anyone else.
How do i find the point of change, put it next to a compass or try and pick it up with a magnet ?
I use those magnetic pickup tools - Maplin sell them IIRC. Don't put it back in your pocket until you are sure it has cooled... :yikes:
I suppose there is no need to harden the tang so i can hold that to pass it in and out of the heat....
Hmph ;)
I caught an episode of "ultimate weapons" at the weekend on satellite, all about the Samurai Sword, showing how they make em, how they put the Hamon on with using a thin layer of clay. They were using the box bellows or grand piano, exactly like Peter had at the meetup. But not in the sand , on the floor in one of those Japanese paper houses !!! :shock:
Not that I'm jealous or anything - I'm still sweeping sand out of the 110! Don't suppose anyone has a copy of that in a format I can read?
Those bellows are great. propel air in both pumping directions. That is how the Chinese has Steel 1500 Years before we did in the west ! :notworthy
And the valving is so simple, but works incredibly well. The volume of air that you can shove through the tuyere is incredible - don't remember if you saw the chunk of scaffold tube after I dismantled the forge, but it had melted...
I've still got some more work to do on the knives before hardening - thats what BB does :shock: Kind of puts my amateur efforts to shame.
Amateur = not getting paid for it :-)
I use those magnetic pickup tools - Maplin sell them IIRC. Don't put it back in your pocket until you are sure it has cooled... :yikes:
Got one of these stuck to the frame of my forge
http://www.screwfix.com/sfd/i/cat/08/p1185108_l.jpg
but used to use one of the magnets out of a heavy duty magnetic cupboard latch .. kind you can get in B&Q etc.
http://www.screwfix.com/sfd/i/cat/04/p1746604_l.jpg
I suppose there is no need to harden the tang so i can hold that to pass it in and out of the heat....
Hmph ;)
:wink: :o):