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pcarpenter
01-13-2010, 03:00 PM
This is really off topic, but does fall under that heading of being independent enough to fix rather than replace stuff.

We have a Braun coffee maker that makes pretty good coffee. I probably got my money's worth out of it before it started leaking last week, but I think I can fix it.

I can see where inside the water reservoir they appear to have maybe thermally welded the bottom to the sides and a thin line opened up...coincidentally just after we cleaned it with vinegar and water. I wondered about using some silicone sealant to close this gap and make the coffeemaker usable again. The water only sits in this reservoir for a few minutes while the coffee perks.

Is it safe?

Paul

Boucher
01-13-2010, 03:16 PM
Silicone lubricant was the approved lube for O-rings in Water treating equipment like Water softners and R O units. We used it on O-rings in Sch 80 PVC unions in potable water systems. I think you are safe but I have been out of things for a while now.

Fasttrack
01-13-2010, 03:22 PM
My Dad fixed his coffee pot with silicone caulk. He hasn't had any major health issues ... yet ;) :D

Rookie machinist
01-13-2010, 03:30 PM
There are silicons that are FDA approved. I would check with the maker of the silicon first, but it should work.

Evan
01-13-2010, 03:32 PM
It shouldn't pose a problem. There isn't enough to be concerned about and once it is cured it isn't mobile. It doesn't kill fish and fish are many times more sensitive than humans.

That said, one should try to minimized exposure to materials that contain silicone oils. There is a double blind, double controlled study that shows a high correlation between leaking silicone oil breast implants and the incidence of fibromyalgia. As an anecdotal report I have fibromyalgia and I worked with large quantities (gallons at a time) of silicone oil for over two decades during which time my fibromyalgia symptoms gradually appeared and worsened.

rockrat
01-13-2010, 03:38 PM
Evan beat me to it. I have used silicone to fix the fish tank many times. And I have been told that fish are the first to show signs of issues before the water can hurt humans when consumed. All my fish are still good to go.

I would let it dry, off-gas and then clean it to eliminate any taste issues.

rock~

cuslog
01-13-2010, 03:41 PM
I used to keep tropical fish.
IIRC fish don't like the common hardware store silicone.
I think there's one made specificly for aquarium use (sealing the glass panels). Maybe that's the one to use ??

Evan
01-13-2010, 03:44 PM
The regular caulking silicone contains a fungicide that you don't want to drink. Get the type for aquariums and it will be fine. I should have mentioned that. Thanks Cuslog.

pcarpenter
01-13-2010, 04:06 PM
I appreciate all the advice and I figured by and large that it would be OK, but I was potentially transposing some logic in the process:

While I was pretty sure that some of the sealants off-gassed formaldehyde compounds in the process of curing, there are all sorts of direct-food-contact silicone bakeware which lead me to conclude that at least some silicone products were inert after curing. My wife has a nifty silicone rubber muffin pan that works nice for popping out the muffins unharmed (for example).

I was going to use some black (RTV type) gasket sealant, but I think I will go with the (hopefully more pure) stuff as mentioned.

Paul

Michael Hall
01-13-2010, 05:05 PM
If it is coming in contact with food I would look for the NSF marking to ensure it is food grade quality.

This explains the NSF marking:
http://www.nsf.org/

Michael

Ernie
01-13-2010, 05:13 PM
My brother used to maintain a lot of fish tanks, doing his own repairs. All the glass panels were sealed with silicon caulk. He said that since fish, especially tropical fish, were so sensitive and easily killed, to make sure you only use the CLEAR sealant so as to not have any pigment of any kind in contact with the water. For your purpose, it should be just fine.

Ernie

SpyGuy
01-13-2010, 05:13 PM
If it is coming in contact with food I would look for the NSF marking to ensure it is food grade quality.

Agreed. And you should keep the coffee maker out of service until the caulk fully cures.

rockrat
01-13-2010, 06:07 PM
Yup, I jumped in on this a little quick myself. The stuff for my aquarium did carry a NSF label. Glad you didnt rush out a purchase a tube for front door seals or something similar.


rock~

Evan
01-13-2010, 08:12 PM
The odour that comes off silicone sealer is nothing to worry about. It's vinegar. Acetic acid is the active agent that catalyses the reaction so no worries about formaldehyde.

andy_b
01-13-2010, 09:11 PM
The regular caulking silicone contains a fungicide that you don't want to drink. Get the type for aquariums and it will be fine. I should have mentioned that. Thanks Cuslog.

That is exactly what I was going to say. Don't get the stuff from Home Depot, get it from an aquarium store and you'll be good to go.

andy b.

spope14
01-13-2010, 09:14 PM
Fish stores sell aquarium caulk/silicon. For the purpose, this should work very well. I had a tube that I used, still have 1/2 of it somewhere, it lasts quite a while.

darryl
01-13-2010, 09:44 PM
Don't know if it applies, but the talk about silicone reminds me of the lack of curing issue. I've had some silicone myself that wouldn't cure- I think the reasons for that came to light a couple years ago. Maybe check the expiry date and if it's old, do a test before committing to the project.

jugs
01-14-2010, 03:29 AM
It shouldn't pose a problem. There isn't enough to be concerned about and once it is cured it isn't mobile. It doesn't kill fish and fish are many times more sensitive than humans.

That said, one should try to minimized exposure to materials that contain silicone oils. There is a double blind, double controlled study that shows a high correlation between leaking silicone oil breast implants and the incidence of fibromyalgia. As an anecdotal report I have fibromyalgia and I worked with large quantities (gallons at a time) of silicone oil for over two decades during which time my fibromyalgia symptoms gradually appeared and worsened.

Did you have big implants ?? :eek:

Fibromyalgia Info @ - http://www.ei-resource.org/illness-information/environmental-illnesses/fibromyalgia-(fms)/

macona
01-14-2010, 05:04 AM
My brother used to maintain a lot of fish tanks, doing his own repairs. All the glass panels were sealed with silicon caulk. He said that since fish, especially tropical fish, were so sensitive and easily killed, to make sure you only use the CLEAR sealant so as to not have any pigment of any kind in contact with the water. For your purpose, it should be just fine.

Ernie


They make tanks with black sealant as well. Its probably just carbon black mixed in anyway.

Get any true RTV Silicone like the GE Silicone II. Most caulking is a acrylic silicone that is water soluble for clean up and dosnt last in the long term.

Evan
01-14-2010, 05:46 AM
A warning about the GE Silicone II product: It has a limited shelf life even if not opened. This isn't clearly stated but as the product ages it takes longer to set up. Eventually it will not cure at all and presents a truly nasty clean up job. This occurs within a couple of years or even faster depending on storage temperature.

GE Silicone I is still available and does not have this problem. As it ages the reverse is true, it eventually hardens in the tube.

whitis
01-14-2010, 11:01 AM
Pure RTV has good biological compatability and some forms are used in surgical implants, etc. However, there are many additives. Dyes, Anti-microbial, thixotropic additives, paintability additives, etc. Platinum vs tin cure makes a difference; platinum cure is preferred for prolonged skin contact. Caulks tend use acetic acid (vinegar) or hydrogen peroxide, neither of which should be a problem for humans though the acetic acid one may contribute to corrosion (it can for electrical wiring).

If you look closely, the FDA approval may be for INCIDENTAL food contact.
Immersing in boiling water and then drinking the water and doing so on a repeated basis is hardly incidental. Various silicones have different maximum temperatures. Some can take quite a bit, others aren't that far from boiling water. If your pot runs dry, will you exceed them and create decomposition products before the thermal override kicks in.

Yes, fish are more sensitive to a lot of things than we are. But is the water in their tank boiling? Are they sensitive to everything we are? The fish test may be an excellent way to provide a sensitive early warning for some subset of adverse reactions but they are not a good human analog.

On the other hand, there are silicone baking pans and other things which have direct sustained food contact at high temperatures. But you may have a hard time getting that formulation in small quantities. There are solar water heater collectors that are designed for potable water that use some sort of silicone for seals. There are probably silicones used in applications that involve simultaneous heat and direct food contact in food process plants.

I think there are silicones that will probably work in that application, but many that will not work. Even a crappy silicone is probably safer than many other commonly used substances in many applications involving human exposure. But this particular application is probably one of the least forgiving. Do you want to drink additive tea? There are many formulations out there and it is actually hard to get most of them in small quantity. There are almost certainly some formulations that would be suitable for this application but there is a good chance that the out of pocket expense would not be justified to save a pot that has already corroded through and probably will again.

I am a bit skeptical of the silicone oil fibromyalgia link, especially considering the past history of blaming silicone oil for medical conditions it did not actually cause. Here is a page by someone who has implants and fibromyalgia (which predates the implants) and seems to be making an effort to stay grounded in facts that is also skeptical but also points out that there are some other effects (as there can be with any foreign body) and that injecting it is not a good idea.
http://www.yestheyrefake.net/liquid_silicone_risks.htm

Evan
01-14-2010, 12:57 PM
I am a bit skeptical of the silicone oil fibromyalgia link...

There is now a simple blood test called the Anti Polymer antibody Assay (APA) that is in trials. It tests for a seropositive reaction to the presence of antibodies specific to silicone products and has excellent predictive value with a very low false positive rate. 68% of patients with severe fibromyalgia and breast implants test positive with the assay whereas patients with Lupus which has similar symptoms present only a 3% positive rate. Even without the breast implants fibromyalgia patients test positive at a much higher rate than patients with other chronic pain disorders.

From the company developing the test:

http://www.autoimmune.com/APASciSum.pdf

Rich Carlstedt
01-14-2010, 10:55 PM
I must be old guys, because I remember the warning from years ago

http://books.google.com/books?id=CeQDAAAAMBAJ&pg=PA28&lpg=PA28&dq=dishwashers+silicone+repair+arsenic&source=bl&ots=zdTsgocpVp&sig=9m3nSx-MwCL6E-bMgJrZg3oNlwI&hl=en&ei=TeZPS46UBY-LlAeYwb2oCg&sa=X&oi=book_result&ct=result&resnum=5&ved=0CBgQ6AEwBA#v=onepage&q=&f=false

Some Silicones have Arsenic in them
Better be careful

Rich