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  #11  
Old 06-16-2015, 08:49 PM
SWT Racing SWT Racing is offline
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Interesting question Bluebeard. The HF from a TIG machine can do weird things to electronics. I've had 2 electronic key fobs for my truck reprogram themselves, and 2 outright quit working after TIG welding with them in my pocket. All from welding on AC. . .probably from continuous HF.
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  #12  
Old 06-18-2015, 11:12 PM
Oldnek Oldnek is offline
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Originally Posted by SWT Racing View Post
Interesting question Bluebeard. The HF from a TIG machine can do weird things to electronics. I've had 2 electronic key fobs for my truck reprogram themselves, and 2 outright quit working after TIG welding with them in my pocket. All from welding on AC. . .probably from continuous HF.
The same goes with Microwaves, they also have an effect on key fobs and Garage Door remotes. It took 2 lots before I realised, and then moved the key holder to another location in the Kitchen.
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  #13  
Old 06-19-2015, 09:34 AM
weldtoride weldtoride is offline
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Originally Posted by Norm Swenson View Post
.... To make a long story short, St Jude supplied a unit and programmed it to withstand limited outside interferance. I can weld (stick,MIG,Tig) up to 400 amps.... and ground must be close to the stinger.......

Norm
Norm, great to hear that you can still weld with your unit! My dad has worn a pacemaker for 2 years now, he is allowed to microwave with his, and does almost daily. However, he has no inclination to weld nowadays...

This is not meant as medical advice, just of possible interest.

Running the leads next to each other tends the emfs to cancel each other as the leads are conducting current in opposing directions (one out, other back). I assume that's why the Lincoln guide posted earlier suggests taping the leads together.

A teaching demo to illustrate the emf around a current carrying wire that I used to do in the electrical unit in my auto shop classes was to run long heavy battery charger leads out to a battery that was on the bench. I ran the leads close but not touching, and as parallel to each other as I could arrange, while still suspended in air from the charger several feet away. When the charger was switched on/off, the copper cables would move in relation to one other. How much depended on the charge rate, and the initial distance. This was a commercial charger capable of jump-starting, so the highest rate was on the north side of 200 amps. Copper cables obviously aren't magnetic, but the fields are.
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Last edited by weldtoride; 06-19-2015 at 09:53 AM.
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  #14  
Old 06-19-2015, 09:40 AM
bluebeard#1 bluebeard#1 is offline
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One of my friends sent me a link to a medical company which gives a run down on household goods as well as workshop machinery, it has 3 lists 1 is no concern or danger #2 was keep at least 6 inches to a foot away and 3 was a no go or dangerous list which included welders. But at the end of the what not to do it said if you keep the leads to one side, the earth as close to the welding point as possible and stay 2 feet from the stick or gun and if the unit is under 160 amps you can weld with some safety. It also said that wearing a shielding coat or such is a waste of time as it makes no difference to the emf. I have not heard back from St Jude medical yet but if I do will then ask about getting the thing adjusted for the outside interference and will let you guys know what they say.
Steve Andrew and John thanks for your replies.

Bluebeard.
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Old 07-07-2015, 03:33 AM
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It may work in your favor John if the welder gives you a bit of a charge up..... Some good info here.
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  #16  
Old 07-07-2015, 06:12 AM
bluebeard#1 bluebeard#1 is offline
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Hi Roy,
that might get me going again as I don't have a lot of get up and go yet but I might get addicted to it and become a power junkie.




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  #17  
Old 08-12-2015, 06:04 AM
bluebeard#1 bluebeard#1 is offline
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G'day to all who have been reading this, I have had my visit with the doctor who did the implant and he said the same as the message I got from St Jude medical [ the manufacturers of the defibrillator] the day before. I can use a welder as long as it is not 400 amp or larger, but there are stipulations to how I use it. #1 if doing tack welds make sure there is a 5 to 10 second gap between tacks as rapid consecutive welds simulate heart beat and set it off so using a spot welder and doing a fast run along a flanged edge would also do the same. #2 try not to do to long a run, keep it to a minimum. #3 keep the welder unit as far away as possible, keep both leads together and to one side.#4 have someone with you when you first start back welding in case it goes off which is like being punched very hard in the chest. #5 if you start to feel light headed or dissy turn off the welder and sit down for ten minutes. The rest where the usual common sense things we all know such as welding in the wet etc, so I will give it a bash in a couple of days when the shed is sorted out and room is available.
Thanks to all who put up there ideas and comments..
Bluebeard.
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  #18  
Old 08-14-2015, 10:42 PM
weldtoride weldtoride is offline
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Great news, John.

Getting old is inevitable. Giving up working in my garage is not a specter I want to face.
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Old 08-15-2015, 06:38 AM
bluebeard#1 bluebeard#1 is offline
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G'day Mark,
thank you for your time to answer and your comment, I have a mate who is in his late 80s, he was the Mick Dohan of motorbike racing over here in the late 40s to the late 60s . He is almost in a wheelchair these days but won't give in for anything and if looking for Ray just head to the shed and he will be building another bike or making something for a project but never sitting idle.With out his workshop he would not last a week. I have learnt a lot about perseverance from just watching and working with him. So as I have learnt from Ray don't give in.

Bluebeard.
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  #20  
Old 08-15-2015, 12:49 PM
kjc kjc is offline
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Interesting coincidence.

I worked for a start up company called Ventritex who designed implantible defibrillators from 85-97. I was the first of the engineering team and was responsible for the electronics (the "chip" design).
In 1997 we were acquired by St Jude medical who had no defibrillator technology. For about ten years after acquisition at least St Jude continued to use my electronics.

I'm just stating this to establish some form of credibility I guess.

Anyhow, you can be sure that no one at St Jude - or any other defibrillator manufacturer has tested their defibs alongside an arc welder.
Yes, when we design the electronics we do our best to suppress emi, but it's actually quite difficult for a number of reasons.

Clearly, what you don't want is for the device to inadvertently diagnose tachycardia, although its first response should be ATP (anti-tachycardia pacing) before it "ups the ante" to cardioversion or defibrillation. ATP is unlikely to bother you too much, but I would not want to receive an unnecessary defib shock. Again, these"tiered therapy" devices will shock at lower voltages first (after ATP), even so, best to avoid it.

I dunno, if it were me I would tend to stay away from the arc/tig welder. There's a lot of pleasure in becoming a good gas welder (not there myself but enjoying the journey), so why take the risk?

You'd also be surprised how many E.P. Docs know very little about the devices they implant - cardiac devices are hugely programmable with features and options but most devices get implanted at factory default settings! Your guy may be different, who knows?
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