Old Burco with exposed element

[firewater]

Hi has anyone used an old burco with the exposed element its a 3kw I have wired it so it doesnt cut out its my first experiment will it be too hot this way. Ihave ran it with water and it works fine with the condenser I built also any ideas on sealing the lid. Regards Firewater

[YHB]

I use an old Burco with an exposed element all the time - it works fine.

There are various type of lids for Burcos with different "lips" some lids have flat lips, I was lucky enough to get one with a semi circular lip.

I filled the lip with a silicone mastic that was free from preservatives and fungicides, used petroleum jelly as a release agent on the boiler mating surface, left the seal to cure for two weeks and Bob's your uncle, it has sealed every time since.

Here is another alternative viewtopic.php?f=15&t=1398

[John51]

With using the silicone baking sheet, it doesn't matter much what metal the lid is made from.

The clips I got from here, 3 packs of 8 x 32mm:

http://www.ebay.co.uk/itm/321021126851? ... 1439.l2649

[firewater]

Hi YHB thank you for your reply do you happen to know the name of the silicone.I have done a run and it was great but I had to keep turning the boiler on and off so it didn't get too hot. How do you control the temperature. I used a washing machine door seal it worked fine but a little awkward. Thanks to all who replied

[YHB]

Firewater,

You do not want to control the temperature; the boiler will get as hot as the boiling liquid inside. If you are boiling water it will be 100 deg C if you are boiling a wash it will be lower, the more alcohol the lower the boiling point.

The more power you apply the more violent the boil and the more vapour will be produced but the temperature will not increase. When you have your power controller installed you will be able to dial in maximum power to give maximum vapour for a stripping run and reduced power for a gentle rolling boil for a spirit run.

The washing machine door seal sounds ingenious, but do you know what it is made of There are many forms of rubber and plastic but most are not safe to use, many forms of rubber / plastic will leach harmful chemicals into the still. Silicone sealer is a good example, there are many varieties available and most have additives for specific purposes, ie to reduce mould many companies introduce chemicals that are poisonous to the mould and unfortunately humans as well.

Unfortunately I cannot recall the name of the silicone sealer that I used; I did buy it from a dealer selling Koi Carp and all the paraphernalia that goes along with them. These dealers sell a sealer without additives for making aquariums. Silicone appears to be inert and suitable for our purposes once cured, but releases chemicals during the curing period.

Please be sure that whatever seal you use is inert and fully resistant to alcohol and is fully cured. If in the slightest doubt about the suitability of a sealer then either use flour and water paste, or alternatively, wrap a cardboard gasket with a couple of layers of PTFE tape.

[John51]

This should do:

http://www.ebay.co.uk/itm/150732854187? ... 1439.l2649


There are instructions on the page for making gaskets.

[Almanac]

STOP!!!!!

The product HA6 RTV Marine Silicone refered to in that link is NOT suitable for use with products to be consumed by people - like food or drink.

The product MSDS Sheet clearly states:
"...S1/2 - Keep locked up and out of the reach of children.
S13 - Keep away from food, drink and animal feedingstuffs."

That'll be a NO for use with a still.

Look for "EPDM Gaskets" - many suppliers and manufacturers out there who will gladly make what you need for little money.

Be careful out there

AM

[chill]

Good catch Aidan!

People: you need to be REALLY CAREFUL with what the ethanol comes into contact with. Especially hot ethanol. A hangover can be the least of your worries.


Chuck

[John51]

Wow, if I hadn't posted that link, Aidan wouldn't have caught it and at some point I'd have used it.

Thanks Aidan.

I'm sure that I've read about aquarium grade silicone being ok, obviously not all of them.

[YHB]

The silicone is very similar to the one that I used, the datasheet is very similar to the one with the one that was supplied with "my sealer".

I checked with the manufacturer of "mine" before I used it and have called the technical department of the stuff linked here today and the response was the same in both cases.

The warnings apply to the product "as sold" and not when it has cured and is in use.

The warning - "keep out of reach of small children" applies to a very strong glue and is intended to prevent the little B****s sticking themselves to the glass.

Similarly the bit about keeping it out of the food / drink of animals etc, is to prevent them eating raw glue that will stick their inards together.

As I said, based on the talks with the technical department I left the silicone cure for over two weeks, during which time it lost all the smells and and stickyness and felt just as other silicone gasket materials.

It is up to every individual to decide for themselves, but having talked to the technical departments of two companies marketing this product, I am happy to keep using it.

The company I talked to today is currently updating the data sheets and have promised to address this issue and when they have completed the exercise will send me a copy, which of course I will pass on.

Toodlepip

[firewater]

Hi YHB thanks again for your reply the washing machine seal does not come in contact with the inside of the still it seals on the outside i will post a pic might help someone. I was going to use silicone but was persuaded not too and i had the same idea for the Vaseline so as the saying goes great minds think alike. I had 17 ltrs of wash produced by grape and a small amount of apple but I listened to my son who is an expert on brewing beer and did not put enough sugar so I only got 3 ltrs but it tastes great really smooth. What is the best way to test its strength

[Phantom]

Just for info, the seal material, if it were dangerous etc, doesnt have to come into contact with the inside or even the liquid.....

To be an issue, it only has to come into contact with the hot vapour.... so with something as pervasive as ethanol, if its likely to have even the tiniest bead of silicone between the 2 metal surfaces of the side and lid there will be potential to contaminate.

Being of a cautious nature I'd point out that there's always the old fall backof flour and water paste.......

Though I'd have no problem with cured pure silicone as they do make bungs and other stuff considered food grade from it.....

[John51]

After further reading, I've gone off the idea of having silicone covering the lid of the Burco.

As I'm hoping to be getting 95% spirit from the reflux I'm playing safe and it's going to be cardboard/ptfe gaskets for the tank connector and steam vents.

The airstill will be stripping the wash so the reflux will only get used about 30 times a year, flour paste to seal the lid won't be too much of a hassle.

[Almanac]

Let me backtrack just a little and qualify what I meant in relation to the product in question.

First, I'm not a Chemist. For this reason, when it comes to deciding whether a product is safe to use with ethanol or not I tend to err on the very cautious side because I think it's the safest thing to do and because there are alternative products available that I know are safe. .

The MSDS for HA6 RTV Marine Silicone says "Keep away from food, drink and animal feedstuffs". It doesn't say this applies in the raw state or that it doesn't apply when it's cured or that it only applies on Sundays so, personally, I'd simply look for an alternative product.

That said, I have to reiterate I'm not a Chemist and I could be and may well be technically wrong on this one and if there were no alternatives I'd probably have to reconsider but there are alternatives - loads of them.

It's not my intention to step on anyone's toes here but what I posted was in the interest of safety. I don't care about being right or wrong but I'd rather be safe than sorry

AM

[Phantom]

Let me backtrack just a little and qualify what I meant in relation to the product in question.

First, I'm not a Chemist. For this reason, when it comes to deciding whether a product is safe to use with ethanol or not I tend to err on the very cautious side because I think it's the safest thing to do and because there are alternative products available that I know are safe. .

The MSDS for HA6 RTV Marine Silicone says "Keep away from food, drink and animal feedstuffs". It doesn't say this applies in the raw state or that it doesn't apply when it's cured or that it only applies on Sundays so, personally, I'd simply look for an alternative product.

That said, I have to reiterate I'm not a Chemist and I could be and may well be technically wrong on this one and if there were no alternatives I'd probably have to reconsider but there are alternatives - loads of them.

It's not my intention to step on anyone's toes here but what I posted was in the interest of safety. I don't care about being right or wrong but I'd rather be safe than sorry

AM

No Aidan, you're like the rest of us, an amateur chemist, exploiting the chemical property of ethyl alcohol and helping it on its way in parting company with its friend, the water......

I'm also an amateur gynaecologist, as I work with a bunch of c.....