Stop that cast iron table from rusting

[Robert Lee]

I would like to get some feedback on a device I have been working on. I have a long history in electronics and have been recently testing on my cast iron table tops a device I have designed which uses a sacraficial anode and impressed current to keep your cast iron tops rust free. A piece of zinc (sacraficial anode) is connected to the underside of your cast iron table top. An electronic circuit impresses a low DC voltage and current through the table top and the anode. Without getting into to much depth, the theory behind this is that the anode will corrode and not the cast iron. I removed any wax which I was previously using to keep the rust off, and have had this device on my table saw since october and have no rust or even a haze of rust as of yet. I live in michigan and the winters are terrible on my tools with cast iron table tops. The device seems to work great for condensation and humidity (no rust), but when water is directly splashed on the table, the device seems to slow down the corrosion process but not totally stop it. Is there a market for a device like this out there? Just want some feedback.

[tod evans]

robert, most folks will be waxing their cast iron for lubrication anyway so i would look at this device as an unneeded gizmo...02 tod

[John Shuk]

There are alot of people who live near the coast. Might help there.

[Brian Hale]

Wax is a no brainer for me. A fresh coat every few weeks and no rust. If i lived in a very humid area and traveled extensively, i might have some interest but the cost would need to be low to get me to buy in.

I'm Not trying to discourage you! Just my initial thought. I appreciate the effort and engineering involved in any product venture so don't give up!!

Brian :)

[Kirk (KC) Constable]

Personally, I think this is a good idea...but even if it were a useless gizmo, which I don't think is, if you could sell it for less than $50, it would probably take two people to buy one and start gloating on a forum...and then you'd be covered up in orders.

KC

[David Fried]

In an unheated shop condensation is the killer for me. If I can still wax things and this helps, really helps, I might be your first customer.

Dave Fried

[Marc Kohlbauer]

My garage/shop could use several of those. Not just the table saw, but the bandsaw, jointer, drill press and moriser too. If you could keep the price low enough, I would be interested!

:)

[Lou Morrissette]

I live about 3/4 mile from the Atlantic and rust is a major problem. Up until now, faithful applications of wax are the norm. If this system works and is in a reasonable price range, it could be attractive in this area. As has already been said, I would still use wax as a lubricant on the flat surfaces. Would this system still work?

good luck

Lou

[Kent Parker]

Robert,

Your system appears to be both a passive system and an active system and I must say confusing to me to say the least:confused:

In basic corrosion theory if you can reverse a metals natural potential (voltage) approximately 200 ma it will stop corroding.

To achive this in a passive system, it is common to attach a Mil. Spec. zinc anode (or Magnesium or Aluminum anode) to supply electrons to the cathode (the metal you choose to protect). Additionally, the anode and cathode need to be in the same electrolyte in order for an exchange of ions to take place.

An active system or impressed current system requires a direct current source. With this type of system an anode is attached to one side of the current source and the cathode to the other. The quantity of electrons flow is usually measured against a reference electrode (typically a zinc or silver-silver cloride cell) and the power source is regulated to allow the correct amount of protection. Lack of regulation can be hazardous. As with the passive system, an electrolyte is needed.

You appear to have electrical experience so please tell me, why do you think your system (s) are working?

BTW, wax is really easy.

Cheers,

Kent

[Rob Blaustein]

Interesting idea-sounds like what's in our hot water heaters. Sounds like you and Kent will have an interesting discussion. Whatever mechanism you invoke, I would ask that you please avoid:

1. violating the first law of thermodynamics
2. invoking "cold fusion"

[Allen Bookout]

Twenty years or so ago I was looking into building a steel sailboat and they were working on a system that sounds like that it might be simular to what you are working on. I do not know how effective it was or what ever happened to the project. I think that Steve Dashue (sp) used some sort of this type of system on the aluminum sailboats that he built.

If you could make it work effectively and produce it for a reasonable cost it might be a winner. I live right on the salt water and am able to control the rust effectively with T9 and wax but it would not hurt to have some insurance. Could eliminate the T9 and just some occasional wax would be great.

I do not know what kind of a market you would have but since it is not my money, give it a shot. Easy for me to say.

Allen

[Chris Barton]

Your idea certainly works well on outboard motors, boats and hot water heaters. Just don't try it on a Sawstop table saw...

[Norman Hitt]

Well, for me, the old remedies, ie; wax, T-9, etc work adequately, EXCEPT......that I REALLY need someone to invent something that will instantly neutralize "SWEAT Droplets". I seem to be able to flood all my CI surfaces with them in the spring/summer/fall, here in the HOT Southwest, and they will eat through any of the above mentioned protections in minutes if not simmediately noticed and neutralized. They will then start eating and turning the CI black within the hour, creating deep, black pits overnight if overlooked. (I can't even imagine how bad it would be if I lived in Phoenix or Tucson where it gets even hotter). Sometimes I have gotten so frustrated that I considered painting all the CI surfaces with a hard Epoxy Paint to see if it would eliminate the problem.

[Dave Cavner]

This is not an uncommon topic over at http://www.owwm.com

There are even two articles on the FAQs page regarding rust removal. I think the fellows on that discussion list might be a target market.

[Allen Bookout]

Norman hit my bigest problem here in Southwest Florida, sweat drops. Drives me crazy. Allen

[Tom Jones III]

I'm interested in something like that. I live near the gulf coast and I swear on some days I can actually watch my TS rusting! Two problems I see,
1. what is the power source? I don't want to spend either a lot of time or recurring money here i.e. I don't want to buy batteries every week or have to think about it.

2. I'll need a minimum of 4 and could use more. The cost of wax really "shines" here as there is no incremental cost. However, if I wanted to use your system I would have to buy 4-6 units and I would still have to wax. If I have to wax anyway, I would wonder why I should have to pay for your system simply from preventing me from waxing one more machine.

There is one thing you can count on however, early adopters - those gizmo guys will always buy something like this. If you can keep your investment low I'll bet you sell quite a few.

[bill walton]

There is a similar product available for vehicles that helps to prevent corrosion. I don't recall the manufacturer but I saw it on the car show "2 guys garage" or something like that last Fall.

[Rob Will]

Well, for me, the old remedies, ie; wax, T-9, etc work adequately, EXCEPT......that I REALLY need someone to invent something that will instantly neutralize "SWEAT Droplets". I seem to be able to flood all my CI surfaces with them in the spring/summer/fall, here in the HOT Southwest, and they will eat through any of the above mentioned protections in minutes if not simmediately noticed and neutralized. They will then start eating and turning the CI black within the hour, creating deep, black pits overnight if overlooked. (I can't even imagine how bad it would be if I lived in Phoenix or Tucson where it gets even hotter). Sometimes I have gotten so frustrated that I considered painting all the CI surfaces with a hard Epoxy Paint to see if it would eliminate the problem.

Is air conditioning out of the question? A lot of pros that I know say they must have the A/C going. However, it sounds like they are required to clean out the A-coil every year or so in a production shop.

Rob

[Robert Lee]

What I have made and am testing at this point costed me a total of about $15 to make. But I am at no way sure that it is even working the way I hope as of yet. What this device is doing (in therory) is forcing the zinc to give up its over abundance of free electrons and supply them to the cast iron table top which is loosing its few free electrons (causing rust)to the impurities in the steel itself. I have regulated the current, and kept the voltage down to an amount which cannot be felt when you touch the table.
This really isnt new technology at all. This type of cathodic and impressed current protection have been used on watercraft and pipelines for years. In those instances an electrolyte is needed such as water or dirt. I do not have that here in my wood shop, but I am relying on humidity and wood dust(which contains moisture) to be the catalyst along with the impressed current. Anyway I'm having fun just tinkering with the idea.

[Norman Hitt]

Is air conditioning out of the question? A lot of pros that I know say they must have the A/C going. However, it sounds like they are required to clean out the A-coil every year or so in a production shop.

Rob

Rob, I would LOVE to have AC in the shop, Buuuuut.......with the price of Electricity here today, if I ran a Shop AC, I couldn't afford to run the power tools. Kinda puts one between the proverbial Rock and a Hard Place. With the latest increase in Elec. prices here our bills are astronomical even without running any tools.

[Per Swenson]

This sounds like a great Idea.

I wish you well.

For now we have a lot of Iron around here,

and a Sawstop,

and will continue to wax and make duct tape booties

for the Felines who love to perch themselves on the machines.

( It is their shop after all)

(Authors note), No, that is not a Cat Hat in the avatar.


Per

[Dave Mcintire]

Kents got it right - you need one or the other, not both, but I'm not sure either work in air (no electrolite). Most cathodic protection systems are for burried or submersed steel where the dirt or water contains enough electrolite to let current flow.

Also, I found if you use the machine a lot the top will not rust!

[Mac Lyle]

I would like to get some feedback on a device I have been working on. I have a long history in electronics and have been recently testing on my cast iron table tops a device I have designed which uses a sacraficial anode and impressed current to keep your cast iron tops rust free. A piece of zinc (sacraficial anode) is connected to the underside of your cast iron table top. An electronic circuit impresses a low DC voltage and current through the table top and the anode. Without getting into to much depth, the theory behind this is that the anode will corrode and not the cast iron. I removed any wax which I was previously using to keep the rust off, and have had this device on my table saw since october and have no rust or even a haze of rust as of yet. I live in michigan and the winters are terrible on my tools with cast iron table tops. The device seems to work great for condensation and humidity (no rust), but when water is directly splashed on the table, the device seems to slow down the corrosion process but not totally stop it. Is there a market for a device like this out there? Just want some feedback.

I'd be interested in how your empirical test is going with your device. I'm an EE with a little experience with Cathodic Protection, which is what you're describing, but all the systems I know require the electric circuit to be completed through some type of electrolyte or brine. I have doubts that your system would work with only the sacrificial anode in free air (which even if saturated with humidity, probably will not provide the electrolyte solution for the reaction with the anode).

[Rich Engelhardt]

Well Mac - first off, welcome to SMC!

2nd, the original post is a bit over 8 years old & as far as I know, there hasn't been anything yet to hit the market that resembles it - so - I'd say the idea was a bust.

[David Hawxhurst]

there is a company called CounterAct Electronic Rust Protection. not sure its a true cathodic protection but seems very similar.

[Andy Pratt]

I would imagine that if this device worked as described, retailed for $40 or less, plugged into a normal outlet and required less regular maintenance & recurring cost than wax, you would get a lot of people to buy it. Fail any one of those and I'm guessing it is in the fringe gizmo category. If the thing really worked well (let's say it even stopped water spot rust) maybe you could get manufacturers to include it on the machine, wired right into the existing wiring.