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DrT
-3rd June 2003, 08:04
What's the best way of putting a gentle, permanent curve into a blade? I have real trouble getting anything more than a tiny bend in it!

I've heard I shouldn't try to do this by just bending it in my hands but I see a lot of people doing this. What's the secret?!

Gav
-3rd June 2003, 08:11
There is no secret. I bet you'll get loads of advice about this. From my point of view, and I've only broken one blade in the last 3 years - touch wood, the best way to break it in is to run it under your foot moving the blade in and out and increasing the bend slightly till it has a minimum curve that you're happy with. After that the blade seems to take on more and more of a shape that I am happy with over time as you use it. I wouldn't recommend using a new blade against a beginner though. All it takes is one bad lunge/fleche to put a really nasty kink in it. You'll be ruing using it for ages afterwards [that happened with my last blade].

Muso440
-3rd June 2003, 08:11
Stupid newbie question: why would you want to?

Hudson
-3rd June 2003, 09:07
some people bend the blade to help them get round the guard/ deffence of their opponent. Or to help with flicks.

pinkelephant
-3rd June 2003, 09:38
It helps to make sure the blend always bends the right way when you hit. However, you need to bear in mind the maximum bend:

1cm at epee
2cm at foil
4cm at sabre

The bend is measured by placing the blade on a table and measuring the maximum distance from the flat surface to the blade (without any downward pressure).

Interestingly, the rules say that the bend for foil and epee has to be "in the vertical plane" - it can therefore be either downwards or upwards.

Rdb811
-3rd June 2003, 09:44
Originally posted by Muso440
Stupid newbie question: why would you want to?

So that it bends in a consistent manner - if it's straight then a hit that bends it up, followed by one that bends it down can lead to a 's-shaped blade' - which then has a weak spoy where it could snap.

An upward bent blade is dangerou as it could get under the bib of the mask.

Rdb811
-3rd June 2003, 09:46
Originally posted by DrT
What's the best way of putting a gentle, permanent curve into a blade? I have real trouble getting anything more than a tiny bend in it!



Either stand on the top of the blade and pull it under your foot using the FRICTION to bend it. Or rub the blade vigously witha towel (e.g. an old bar towel) and then held on the blade bent for a bit.

hokers
-3rd June 2003, 10:44
Be very careful though, I've seen people snap blades when bending them back to shape in their hands, very dangerous. Under the foot is the recommended method.

Doesnt the maximum bend at sabre have to be with the weight on the end? Hence all the S2000 blades?

hokers

Rdb811
-3rd June 2003, 10:55
The blade bend (4cm) and flexibility are two separate critria - the flexibility test is :
The force is 200 gms 1 cm from the point, the
blade clamped 70 cm from the tip - the flexibility is 4-7 cm
I know all this as we had a query at the club a few years ago - basically the
second generation Allstar S2000 blades are slightly more flexible and *appear* to be within the higher end
of the range (the test wasn't too scientific as I used the top off a test
weight) - the orginal Uhlmann/Allstar S2000 ("the club cudgel" that all four
of us once in a match) appears to be on the stiff side.

Easy way to test - clamp the blade (all epeeists have clamps for re-wiring
the damn things) stick a 200 gm weight in a plastic bag and put it on the
end or weigh out 200 gm of sugar etc into the bag and use books to hold the
blade in place).

(if that's a bit garbled it's because I'm re-using an old post of mine).

Rdb811
-3rd June 2003, 10:56
Originally posted by hokers

Doesnt the maximum bend at sabre have to be with the weight on the end? Hence all the S2000 blades?

hokers


The range for sabre was 7-12cm, it was cahnaged to 4-7 cm.

pinkelephant
-3rd June 2003, 10:56
Originally posted by hokers
Be very careful though, I've seen people snap blades when bending them back to shape in their hands, very dangerous. Under the foot is the recommended method.

Doesnt the maximum bend at sabre have to be with the weight on the end? Hence all the S2000 blades?

hokers

No - you're confusing the bend itself with the flexibility test, which is indeed done with a weight on the end.

The Second Muse
-3rd June 2003, 20:35
try a large wrench (http://www.vccc.com/images/wrench.gif) , stick the blade in, and twist. The force will bend it. Best done before you put the wire in:dizzy:

Rdb811
-3rd June 2003, 21:02
Originally posted by The Second Muse
try a large wrench (http://www.vccc.com/images/wrench.gif) , stick the blade in, and twist. The force will bend it. Best done before you put the wire in:dizzy:

Not an approach I'd take.

The Second Muse
-3rd June 2003, 23:36
This is for getting a bend in the blade before setting the wire, so you have slack in the wire when it bends later.

Rdb811
-3rd June 2003, 23:40
Doesn't sound very good for the blade - I'd at least get the balde warm beforehand. Any I wire the blades by overbending them when putting the wire on.

The Second Muse
-4th June 2003, 20:26
Originally posted by Rdb811
Any I wire the blades by overbending them when putting the wire on.

It's only bending the blade...how can it damage it? And overbending while wiring is what is being done here.

neevel
-4th June 2003, 21:22
Originally posted by The Second Muse
try a large wrench (http://www.vccc.com/images/wrench.gif) , stick the blade in, and twist. The force will bend it. Best done before you put the wire in:dizzy:

He's referring to my preferred approach to getting a curve set in the blade, which if done right will be more precise and reliable than just running it under your foot.

You want to take the eyeloop of a large wrench (I have a 18" long combo-wrench with which I use the loop socket). Place the blade through the loop, sliding it down to where you want to start training the curve in (typically 1/3-1/2 the way up from the tang). Holding the wrench and the blade in one hand, squeeze them together. Release, slide the wrench about 1-2 " along the blade, and squeeze again. Keep sliding the wrench up along the blade and repeating. This will produce a smooth, gradual curve along the length of the blade. For more pronounced bends, you may have to do this whole process more than once. One you get the feel of it, you'll be able to gradually put in as much of a curve as you want. Since you're only making a small amount of bend at each point where you position the wrench-loop, you're not a risk of breaking the blade. Believe me, this method is more gentle on the blade than pulling it under the foot.

As has been mentioned, the chief reason for curving a blade is to pre-train it so it will bend smoothly and evenly when you deliver a touch, with less chance of it taking a sharp kink.

Now, this is not related to why you bend the blade while wiring. You really should train the curve in before wiring. Then, when wiring, you hold the blade flexed in a jig (but this time you're not going past the elastic limit to set a permanent bend) as a way of both keeping the wire snug in the groove for glueing, and to pre-tension the wire so that it's less likely to break (especially at the solder joint between the wire and contact up in the point) when the blade flexes with a touch.

A handy way to check the curve on blades is to cut a 1 cm x 2 cm x 4 cm wood block. With the blade laid out on a table so that the tang (or guard, for an assembled weapon) is over the edge, if you can slide the block under the curvature with any headroom the curve is too great.

The other place where it's a good idea to put a bend in the blade is at the tang. You want to bend the tang downwards and inwards (i.e., over to the left if you're right-handed, over to the right if your left-handed) so the handle will sit easily in the folds of the palm. Downward cant in the tang also lets you keep your wrist in a more neutral position, rather than having it extended downwards as a fully straight tang forces you to do. There is a limit to the amount of cant you can put in, defined by the requirement that the assembled weapon must be able to pass vertically though a 15 cm-long cylindrical gauge (12-cm diameter for foil, 13.5 cm for epee). As a practical matter, though, you'll never see the guage tests done except at a World Championships or the Olympics.

-Dave

Rdb811
-5th June 2003, 00:13
I was going to ask how to put the ofst in (which isn't really a bend) - the wrench strikes me a s a bit crude and liable to cause a wek point and no-one I know uses one for that purpose) - but if enough of you say it works then there must be something in it.

neevel
-5th June 2003, 19:10
Except for the occasional Russian/Ukranian blades from about a decade ago, blade tangs are annealed so that you won't be harming them putting a bend in. Any method you use to put a bend in the tang is likely going to seem crude (wrench, pipe, or just clamping the tang in a vise and bending by hand)-- bending a piece of metal that thick is inevitably going to require some force.

BTW, for those who don't know me from Fencing.net, I'm one of the US Fencing Associations national armorers (i.e. the people who work armory at national and international tournaments held in the US, and who accompany US teams abroad).

-Dave

Rdb811
-6th June 2003, 00:32
I would't have a problem with a wrench for puttinng the offset on the tang - it was using it for the curve of the blade that I was having a problem with . But I'm happy to be corrected.

It's bit hard to work out who people are on here

Many thanks.