The Vespiary

The Hive => Chemicals & Equipment => Topic started by: procule on December 22, 2002, 07:34:00 PM

Title: Trying to repair glassware at home
Post by: procule on December 22, 2002, 07:34:00 PM
I recently broke a distilling glassware (flask + fittings to condensor all in glassware)  :(

The bottom of the flask has broken and now i'm considering replacing the flask to save the fittings. I've spotted a product, JB-WELD. I've already patched some stuffs with it and it is really impressive. I've even built a ghetto still to make homemade alcohol glueing the pieces together with it.
It's a very resistent "resin epoxy".
Here's some quotes from the manufacturer:

We call our resin epoxy steel because it contains fine particles of ironand steel.
Adhesiveweld has a tensile strength of 278.4kg/cm2.
Adhesiveweld resists temperatures of 300oC and often higher.
Because the cured Adhesiveweld can be treated like metal and drilled,tapped, machined, polished and painted it can be used for a whole variety of applications apart from bonding surfaces/substrates together.
When cured Adhesiveweld is completely resistant to water, oil, petrol,diesel and most aggressive chemicals such as battery acid. It is also non corrosive and non conductive. This means you can use it as a circuit-breakeror where corrosive chemicals are present or in a hard climatic environment.
Adhesiveweld has a shelf life of 20 years, even after tubes are opened.

So what I want to do is to "weld" the two glasswares (the flask and the fittings) with JB-Weld. I'm sure it will work for the welding but will it resist/alter the distilled products ?
They claim it is totally unreactive to *most* products.

Does anyone have any info on JB-WELDing glasswares and his reactivity ?

Here's the URL to the manufacturer's website:

http://www.jbweld.co.uk/files/prodb.html#Feature (http://www.jbweld.co.uk/files/prodb.html#Feature)



Thanks !

The French Canadian Bee
Title: Jb epoxy weld is the shit.
Post by: pickler on December 23, 2002, 03:36:00 AM
Jb epoxy weld is the shit. Swim broke a 300 dollar condenser nipple off and the epoxy saved the day. It might be mostly non reactive but swim wouldn't risk it. It's a general statement from the manfacture. Just get some new glassware.

I went into the business for the money, and the art grew out of it.-Charlie Chaplin

Title: I've made some tests using lye and HCl solution ...
Post by: procule on December 23, 2002, 10:23:00 AM
I've made some tests using lye and HCl solution (muriatic).
"fresh" jb weld reacts violently with HCl but not with NaOH.
On the other hand, "very dry" jb weld seems to be unaffected by HCl even for a long period of time (1 hour).

I know I need to buy new glasswares but I was thinking saving this one maybe for limited uses and use it until I have money to buy the new materials.


The French Canadian Bee
Title: I take my broken glassware to glassblower and get ...
Post by: raffike on December 23, 2002, 10:55:00 AM
I take my broken glassware to glassblower and get it fixed cheaper than you buy that Glue. :)

For those about to synth,we salute you
Title: Bee careful. A technical data sheet for a similar ...
Post by: rydalmere on December 23, 2002, 02:39:00 PM
Bee careful.
A technical data sheet for a similar steel filled epoxy states that the maximum "wet" temperature resistance is 80 degrees C.
The epoxy would probably fail at the bond to glass first.
You would not want this to happen when working with precious substances.
Rhodium's site has information on scientific glassware that I'm sure has information on repair techniques.

The Pot stole my Wit
Title: Ok, I've looked to the MSDS of the JB Weld ...
Post by: procule on December 23, 2002, 03:39:00 PM
Ok, I've looked to the MSDS of the JB Weld product. Here are the components and their quantity in the mix:
(hardener)
- Calcium Carbonate (35-40%)
- Barium Sulphate (20-30%)
- Magnesium Silicate (2-7%)
- Titanium dioxide (1-6%)
- Furfuryl alcohol (1-5%)
- Polyamide resin (15-25%)
- Aminophenol (1-5%)
(iron resin)
- Calcium carbonate (40-50%)
- Iron powder (10-20%)
- Epoxy resin (30-40%)

It may help to determine the reactivity and incompatibility of the final DRY product.



The French Canadian Bee
Title: Why don't you buy a new flask?
Post by: yellium on December 23, 2002, 04:08:00 PM
Why don't you buy a new flask?


Hardcore libertarians consider the idea of a Libertarian Party dangerously socialist.
Title: Like as said, I will need a new flask.
Post by: procule on December 23, 2002, 05:04:00 PM
Like as said, I will need a new flask. But I was going to throw away the fittings that were totally intacts. So I want to save them, that's it.

Btw, i'm currently testing some distillations.
I've successfully distilled methanol, ethanol and DCM.
The welding is intact.
Next test is toluene which has a quite high B.P. for a solvent.


The French Canadian Bee
Title: Even glassblowers keep the fittings only if it is ...
Post by: yellium on December 24, 2002, 03:44:00 AM
Even glassblowers keep the fittings only if it is easily separable; standard mass-fabricated glassware such as three-necked flasks are thrown away if they're beyond a quick repair. Think of the price of labour. In your case, I would also include the cost of lost product, or 'my lab is on fire'.


Hardcore libertarians consider the idea of a Libertarian Party dangerously socialist.
Title: It's also more an experiment.
Post by: procule on December 24, 2002, 07:16:00 AM
It's also more an experiment. It took me about 10 minutes to glue it using jb weld and I waited overnight. I've baked it for 1 hour at ~175F. So it was not that hard and if I can save some materials, why not ? It also can give bees infos about easily repairing glasswares since they are quite expensive. A repaired glassware sure doesn't worth a brand new one but if it can still do works, it worths to repair it.

The French Canadian Bee
Title: Thanks. With idjits like you the gov'mnt doesn't ...
Post by: yellium on December 24, 2002, 11:35:00 AM
Thanks. With idjits like you the gov'mnt doesn't need to fake stories about meth cooks blowing up their mobile home.


Hardcore libertarians consider the idea of a Libertarian Party dangerously socialist.
Title: I don't really understand your point.
Post by: procule on December 24, 2002, 06:51:00 PM
I don't really understand your point. I'm not trying to voluntary make stupid things. I'm trying to save some glasswares. I sure wouldn't use a distillation apparatus repaired with jb weld to do a vaccuum distillation or the reflux needed to cook meth.
But hey, if I can get a broken glassware working to do some basics things like reducing the volume of a solvent without throwing some nastys in the air or things like that, why throw it away ?
I don't think every bees as the money to throw any glasswares that have been cracked to the garbage. I don't think either that every bees have access to a glassblower.
I'm just trying to suggest/test another option. ;)

The French Canadian Bee
Title: Chemists don't repair their glassware.
Post by: Rhodium on December 26, 2002, 09:56:00 AM
Repairing your own glassware is dangerous, and sooner or later you will either cut yourself (best scenario), or if not so lucky you will possibly set your lab on fire due to your cheapness, burning yourself and getting chemical pneumonia from the fumes while you see several grand worth of chemicals/product go up in smoke, all this while the police and fire brigade are on their way to rescue you and transport you to the local jail...

Now, were those $25 for a new flask really worth it?
Title: Calcium Carbonate
Post by: rydalmere on December 27, 2002, 12:27:00 AM
40% Calcium Carbonate (20% in final mix if 50:50)
Don't use acids in the flask.

The Pot stole my Wit