Be Excellent To Each Other

Hello chums,

I want to run something by you, and would appreciate any thoughts and input...

I was recently given the opportunity to try out a new type of knitting needle. (OOoooooooh!), I know.

Anyhoo... Knitting needles come in many types, sizes and materials. I have used: nickel plate, brushed steel, bamboo, wood (of different types including rosewood and laminated birch) and plastic.

These new needles are unlike any of the above. They are a type of clear acrylic, butthey are very different to other acrylic needles I have tried. They are very flexible and light compared to every other needle I have tried, they are also rather 'grabby' in knitter's lingo, which means that stitches do not slide along the needle very readily - this is a bonus in some types of knitting like lace and small objects where your stitches have a habit of just slipping of the needle when you make a cup of tea.



Now... I seem to be experiencing a strange sensation when I knit. The needle in my left hand, which holds al of the stitches, seems to be vibrating at a high frequency as I knit. I think this may be caused as the stitches shuffle continuously up the needle the friction caused b the 'grabbiness' is making the needle vibrate. I have never, ever heard of this happening before - it has certianly neer happened to me with any other needles.

Now, after about 10 minutes knitting my hand and lower part of my left arm experiences a feeling like mild pins and needles, then goes numb, then starts to ache... Then I feel nauseus. Now - I tried knitting with them last night, and wondered if i was just feeling a little off-colour and imagining it - but I tried again today and it has happened again.

So, do you think what I think is happening is plausible? I know that every object has a natural frequency which it will vibrate at under certain circumstances, but do you think it is possible that it is this that is leading to the numbness and then nausea? (It is the nausea that I am most confused about... Is that a likely thing to happen?)

Am I just imagining it? My hand still feels numb now

Wow!

Err, static electricity maybe? Van-de-Graaf generators use acrylic collectors and a belt made of silk or something like that.

Lupus.

The bends.

Oh no.

Could be whitefinger, but I don't think that explains the nausea.

It sounds like the sort of thing Doc Gaywood will explain with his science. He will no doubt need to probe further.

Chemicals on the knitting needle. I would advise you to consult a PI lawyer, then a doctor.

Do you have a Ravelry account? It strikes me that people there might be useful to ask.

FWIW, Mrs Parm knits and has never described such symptoms - or at least, has never ascribed such symptoms to knitting...

Does it happen with other needles?

Hi parm!

I got nothing right now. I need a differential diagnosis team featuring at least one attractive young lady, and a walking cane. Stat.

Ooh, our bitter rivals. I think we pwn them on science though.

*fetches wig*

Hi palm!

It wasn't that good a question...! Ohhh.

To rule that out, try carrying the needle around for a bit without knitting, and see if you still get the symptoms.

Or to rule out static, try linking the ends of the needles together with a piece of wire.

And as Bobby says, it'd be worth ruling out that it's anything to do with the needles at all (and not a migraine or something) by trying with other needles for a while.

If you hold them out in front of you, can you find water?

I've clearly got some history to catch up on.

Hi, everyone! I'm new! Ignore me whilst I stumble around saying inappropriate things to everyone and spilling drinks on your cat. Normal service may be resumed at some point, but normal service may still include inappropriate remarks and spilt drinks.

It's probably aliens.

No worries there.

Where are you from parm? Are you pals with a BeeXer already or did you google search for 'Best 50 games of all time?'

UGVM, I think? Am I right?

The vibration of the needle is at a frequency which is affecting your middle ear after a long enough of an exposure you are feeling sick in the same way you would if you were on a boat and the small sacks that dangle in your middle ear were aggravated by the motion of the boat.

The numbness in your arm is caused by the vibration and is unrelated.

You're not a real doctor are you Nemmie?

Perhaps you just need some sugar before knitting? It's hard working keeping them vibrators needles under control

We need to distill Essence of Vibration, then dilute it a millionfold.

We have. It's myp singing.

Needs to be a double-blind experiment, so pick up two different kinds of needles in each hand with your eyes closed

Or identical twin Mimis with blindfolds on.

This is serious science here, keep your fantasies to yourself.

You are right, indeed. Been meaning to wander of here for a while to see what's going on. Apparently, it's knitting, and science. Which seems ok.

I think Nemmie has got to be the closest here, vibrations can cause numbness, but as to what's causing the vibrations, could it be that the fabric on the needle is "dampning" the resonant frequency of the needle to the exact frequency that Mimi knits?

Mimi, what happens if you speed up or slow down your knitting action?

Malc

The scarf gets made faster, or slower.

Hi Mimi, quick input from me sweetie as I’m still in ‘sulking flounce mode’ being the immature buffoon that I am, however this is a clear health issue which does rather take precedence!

In short, please stop using these needles immediately. Whilst I am unclear as to the actual vibration-inducing mechanism that’s at work here (probably a combination of low needle stiffness as you describe = low resonant frequency, lack of needle damping and slip-stick friction at the needle tips, combined with your particular needle grip, speed and the type of materials being used), what is clear from the symptoms you describe is that it’s not going to do you any favours in the long term.

The symptoms you describe (pins and needles, numbness, aching – finger blanching and coldness would be next) are classical early onset ‘vibration white finger’. Whilst it should be no problem if you stop now and shouldn’t be anything to worry about at this stage IMO, you don’t want to continue exposing yourself to this ‘occupational vibration’.

Here’s a linky for you:

http://en.wikipedia.org/wiki/Vibration_white_finger

Take care.


Cavey

Stand down Doc. It's Cavey time.

But how would the vibration in the hands be causing nausea?



If that was the case, then adding a weight to the needle (like a lump of plasticine on the end) should de-tune it.

We like games too, honest!

I already suggested that. But it is very unlikely with such a small level of vibration and without any history of that (i.e. due to chainsaw or jackhammer use). And it doesn't cause nausea.

Stand back Cavey. It's Kalmar time!

You mean Mimi's not a lumberjack?

When I've used hammer drills before, and had my shoulder effected by the vibrations, it made me feel quite sick too. could not the vibrations travel?

Also, I said closest and not spot on!

Malc

She's still ok, though.

Whilst I accept that the symptoms are worrying, can it really be VWF, Cavey? The energy associated with a knitting needle, even one being driven perfectly at some resonant frequency, is going to be tiny. VWF comes from using industrial machinery like jackhammers.

Also, what kalmar typed after me but before I was interrupted by work.

Disagree. How do we know it's 'such a small level of vibration'? If Mimi can clearly feel significant vibration as she describes, I don't agree with that analysis at all. Besides, the pins and needles and numbness are classical early symptoms of neural stress and as you should know, an individual's susceptibility to occupational vibration varies enormously.

Seems pretty clear cut to me; why risk continuing to use these needles when there's a reasonable possibility of harm being done? I wanted to make sure Mimi was forwarned with this information as a possibility, from someone who's reasonably informed on the subject, for her own wellbeing - I am not trying to score points. So, mission accomplished then.

My understanding of resonance is that it's not the size of the force, it's the persistancy that causes the effect.

Mal

Mimi, yesterday:

Nobody is suggesting she should. What we are trying to do, is to find out what is actually the source of the problem, in a measured way, without jumping to conclusions or recommending solutions without being in possession of all the facts.

Well I've carried out numerous triaxial vibration measurements of a wide variety of tools Doc; you'd be surprised. Of course, jackhammers, angle grinders and kango drills etc. are extreme examples - these invariably produce massively significant HAV levels. However, seemingly innocuous tools can certainly produce some HAV also, and people's susceptibility to it does vary very widely indeed.

I must admit it's indeed surpising that the needles produce this vibration, but Mimi's account seems pretty clear to me, I see no reason to doubt the veracity of it - the vibration is clearly present as she's described. And that being the case, taking the symptoms she's describing, a 'safety first' approach of stopping their use as I describe seems reasonable enough to me? It's her call though of course.

Could it be the "grabbiness" of the two needles rubbing up against each other causing vibration? Could the thread/wool type also be causing this with this type of needle?

mmm where is Iron Side when you need him...

Also consider how easily Mimi is affected by alcohol, she may simply have a low tolerance to physics and science. Or she may be pissed.

True enough.

http://hither-n-yarn.blogspot.com/2007/04/its-all-in-fingers.html is interesting.

Hi! Welcome to the Internet. I take it you are new here?