Turning, buffing and cochlear implants......

[Ken Fitzgerald]

I hadn't turned for a couple years.

2 weeks ago, a neighbor asked me to turn a spindle for a chair he was restoring for his FIL. I enjoyed copying the spindle for him.

On FB, a friend challenged me to display 5 of my turnings in 5 days. I posted some of my old turnings which resulted in another friend asking me to do some turning for him. The 3 grandkids under the age of 5 we have been babysitting left this morning. This afternoon, I chucked up a piece of wood and made a minor turning and practiced a couple different finishing techniques on it.

As I was buffing it on the lathe, I leaned near the tool rest which was positioned out of the way and began drawing arcs through my t-shirt. I have a cochlear implant which provides my hearing. CIs, like most electronics, are sensitive to static electricity discharges. They can damage it even to the point of rendering it unusable.

As a field engineer installing and maintaining MR and CT scanners, I carried and used an electrostatic discharge kit. I will be wearing the conductive wristband and be wired to ground from now on when I am buffing!

[John Coloccia]

Curious, Ken...have you talked to your doctor about that yet? I'm just curious because to actually be damaging, you'd need to actually do something on the device itself. Things liks FETs (JFets, MOSFETS) can be pretty sensitive to static, for example, but it's really only because you're changing the potential of one part of the device (the gate, for example) relative the the rest of the device, and that can cause damage. If taking a hat on and off isn't enough to fry it, I would be very surprised if a shock on your body somewhere would do anything to it.

Anyhow, I'm just curious how it all works.

[Ken Fitzgerald]

John,

The manufacturer provides literature stating static electricity is damaging and I cannot have surgery that utilizes mono-polar electro-cautery.

There are two types of electro-cautery, mono-polar and bi-polar. Bi-polar uses tweezer like devices and the current passes from one element to the other to cauterize tissue.

In mono-polar, typically a lead is attached to the patients body or the patient is placed on a conductive mat to which a lead is attached and current passes from the surgical tool through the body to the other lead.

I can't have an MRI without a minor surgical operation because the implant has a rare earth magnet that works in conjunction with a rare earth magnet in the antenna to hold the antenna of the sound processor to the scalp over the implant. If I would need an MRI, they can perform a minor surgical procedure to remove the rare earth magnet from the implant, perform the MRI scan and reinsurt the magnet into the implant.

One reason I couldn't return to work as an FE is that the microphones are sensitive to x-rays and can be damaged. Thus I could no longer work with x-ray and CT scanners. I could no longer work on MRs because I can't be in the magnetic field as the sound processor is magnetic and the magnet in the implant itself.

I wear a medical alert necklace at my surgeon's recommendation stating my name, cochlear implant, no MRI, no mono-polar cautery.

[Ken Fitzgerald]

BTW, the implant itself contains a lot of circuitry and active components including a computer processor and other active components. But think about this. There is no battery powering it. It takes the RF signal from the sound processor, transmitted through the scalp, rectifies it and produces the DC voltage needed to power the electronics within the implant itself.

[Fred Belknap]

This time of the year I get shocked buffing on the lathe. I fine if I take my shoe off and put my foot on the leg of the lathe it pretty much controls the bite.

[John Coloccia]

Thanks for the explanation, Ken!