Glass Carboy as a Conical Fermentor...

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iBeer

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So I was listening to Basic Brewing Radio last night in the car and they were discussing conical fermentors, and it got me wanting to get one, but I just don't have that kind of money to throw at something that will just save me from sanitizing extra carboys and racking canes. So it got me thinking about ways to MacGyver one at home.
Basically, if you take a glass carboy and turn it upside down, you've got a conical fermentor (in a basic form). The only problem is that you've got no opennings on the top. Well, it just so happens that I just recently bought a 3/4" diamond-tip glass cutter for a bathroom reno project, which would be perfect to drill out a hole in the top to insert a pipe for getting wort in, and blow-off tube for letting CO2 out.
The only problem is that, in the bathroom reno project, the glass counter top that I was drilling exploded, and I'm not entirely sure why (I was going very gently, with a drill press, in a slow up and down motion, and was using a small pool of water as a lubricant - it took me ~ 30 minutes to get through 1/4 inch when it exploded). So short end of it is I don't really understand glass cutting. Has anyone ever drilled a hole in a carboy? If so, how did it go? Do you have any advice? Where did you cut?
Thanks!
 
Aigh.... the glass they use in carboys has never struck me as being especially high-quality. Very cheap glass, it seems. I'd REALLY hesitate to use glass, I would also wonder if you would seriously impact the structural integrity of the carboy by putting a hole in it. DANGER - LOST BEER AND SEVERED ARTERIES!

BUT - what about investing $20 on a Better Bottle?

FWIW, there are some devices that you can buy to convert a carboy into a quasi-conical - but from all accounts, they're complete wastes of money. I would explore those and get some input from people who have used them in designing one of your own.
 
There's always the V-Vessel or the MiniBrew plastic conicals which I've heard some good things about.

The only concern I would have with some of the large MiniBrew's is that with that much volume the yeasties might start to cook themselves if you don't have good temperature controls.
 
Thanks for the advice!
I do really agree with the whole structural integrity of the glass as well. That's why I put up the posting. I never thought drilling a hole into a glass counter top would be a problem! (whoops!)
I'm just hoping that maybe somebody out there has tried something similar and has some tips on what I should, or shouldn't do, based on their experience.
And thanks for the links to the plastic conicals. Those are a lot cheaper than I thought! I would prefer to leave plastics behind and move to an all glass/SS setup, but the cost of those is really tempting!
 
The taper in a carboy isn't steep enough to work as a conical, the whole point of which is to be able to collect the yeast at the bottom and then dump it out of the valve. In a carboy it'll just sit on the sides and not come out when you empty it. There are plastic conicals on ebay that are very affordable.
 
mward said:
The taper in a carboy isn't steep enough to work as a conical, the whole point of which is to be able to collect the yeast at the bottom and then dump it out of the valve. In a carboy it'll just sit on the sides and not come out when you empty it. There are plastic conicals on ebay that are very affordable.

This is true, the angle of the glass is not steep enough and the yeast will not fall to the bottom. You will get some yeast but most will jus stick to the sides.

You are not the first to thing of this, sombody has been selling a kit to flip a carboy upside down for years but people quickly found out it doesn't work very well
 
Thanks again. I agree with what you guys are saying. It's great to have a sounding board to throw ideas at!
 
Next time you try drilling glass, get some of that kid's plasticine clay. Build a dam around the area, that way it will hold more water. My guess is that you it exploded when you broke through, due to the up-and-down motion. Hey, a coat of the plasticine on the bottom also would hold water while you finished drilling, insteasd of all the water running out as soon as you get a little bit of penetration.
 
On your question about the glass tile. Don't hold me to this, but I think your problem is probably in the speed you were drilling. Glass may be different, but when we used diamond core bits to dril 3-6" holes in concrete, the drills we used had very slow rotation. Using a regular drill press probably had too high a speed.
 
I made a conical from the USplastics noted above.The 15 gal version.It works prefect and is nice for 10 gal batches. Hardware from lowes and some bulk head fittings i added a rotating racking port also.
Mully
 
mully911 said:
I made a conical from the USplastics noted above.The 15 gal version.It works prefect and is nice for 10 gal batches. Hardware from lowes and some bulk head fittings i added a rotating racking port also.
Mully

Pictures man, we want to see lots of pictures of this!!:D:D
 
mully911 said:
I made a conical from the USplastics noted above.The 15 gal version.It works prefect and is nice for 10 gal batches. Hardware from lowes and some bulk head fittings i added a rotating racking port also.
Mully

Yes, please show us some pictures, and maybe even a build list. I'd love to have a 15 gal fermenter.
 
If you're using a conical, and you bottle, can you also use the conical as a bottling bucket by adding sugar into the conical? That could make everything sooo much easier. Instead of sterilizing three buckets/carboys, you'd only do one.
 
casebrew/neckbone,
When I was drilling the glass counter top, I built a dam using plumbers putty, just under 1/4" high, and dropped the speed of my drill press to 600 RPM, and with the up down motion, it was very rythmic and the pressure I excerted was just enough so that there would be a nice 'zhinnggg' sound - really very gentle. I compared it to scratching a hole into the glass.
 
I know B3 puts a kit together to turn a carboy into a conical. I havent used it but I would bet you can call them and find out how well it works. then ask them if they use it themselves I do know they brew alot of beer.
JJ
 
Going back to the original poster....your glass either shattered because A. it was tempered or B. because it got too hot. Someone else stated that you need to build a damn around the area you are drilling and fill it with water to cool it. Another option is to get an assistant with a spray bottle who constantly spray the area as your drill. Of course, everyone should be wearing safety eye gear! :D

Before I got into homebrewing, I was into saltwater aquariums. I would routinely drill and help drill holes in various aquariums (non tempered glass) so that people could add certain types of plumbing...I wont get into specifics. We drilled the holes with a dremel, believe it or not. You need two bits...one to make the initial pilot hole and then another to make the cut. It can be done and if done correctly you should not have a failure...especially if you keep your holes on the small size.

But FWIW, plastic would be much easier to work with and then you dont have the fear of it smashing if you didnt cut a nice clean hole. I know the angle on the carboys is not steep enough but I did have a simple idea to possibly fix that and if this isnt highjacking the thread too much, I would like some feedback.

There is a simple little piece of gear you use in aquariums to clean the inside of the glass...a cleaning magnet. One half goes inside, the other stays outside. There are various sizes depending on the thickness of the glass. The magnets are covered in a plastic/epoxy housing and are safe...they dont leach anything back into the water. What if you had something similar to this on the inside of an inverted plastic carboy? Every couple of days you would gently work it around the angle of the neck towards the mouth. That way you could get all the yeast/trub down to the valve for easy harvesting.

I might have to grab a better bottle and try this out.

Bill
 
Billpa,
No worries about highjacking the thread. I put up the post because I'm looking for ideas, and yours is fantastic! I have a couple of those magnets at home, and I'll have to see how well it works. My only concern is that they are made to clean flat surfaces and I wonder how it will work on the curved surface. Do they sell different shapes ... I've only ever seen the long straight ones that are roughly 1.5 inches wide and 4 inches long.
And for the glass expoding - I did use a dam made of plumbers putty so it wasn't the heat. I was being very gentle with it as well. I was told that it could be because it was tempered, same as you. Here's a question back at you, how would you know it was tempered? It shattered in a really wild spiders web pattern that instantly filled the ENTIRE counter top. Could this be the result of tempering, whereas if it wasn't, the glass may have just shattered or cracked in the region that I was drilling?
Also, does anybody know if glass carboys are tempered? Or is it possible to retemper a glass carboy after you cut it?
 
That sounds like your glass was tempered iBeer. I dont believe carboys are tempered. Retempering is not possible nor necessary IMHO. Tempering is more or less used to strengthen thinner glass.

In regards to your question about the magnet...yes they are only straight but it still might work. Best case scenario would be to custom make the magnet so that you can take into account the curve.

Bill
 
To drill glass without break thru or it shattering you need to fill the carboy with wet sand.. to act as support from the interior. Ive done this numerious times on smaller projects and it works fine.. and as well get constant lube and dont go too fast. good luck.

Cheers
 
How did this end up for the OP?
Did the plastic conical construction photos ever get posted?
 
+1 for the glass being tempered especially if it spiderwebbed like that.

As for the magnet I know exactly what you are talking about. (I have a 90 gal FOWLR). I think if you put the part that is supposed to be on the outside, the side with the felt, on the inside and added more felt to make it into a curve that it should work. Just my 2 cents though.
 
Neckbone- FWIW The speed on diamond core bits for concrete has to do with the slurry glazing over the diamonds. Not sure if there is the same issue in cutting glass.
 
So chaps,

I have been racking my brain about how to use my old glass (acid) carboy which i use as a fv, upside down to make the most of the conical shape...
I have been going through the same thought process as yerselves about how to make the hole on the bottom for the airlock etc.
Ive been searching forums etc and i came across this thread describing exactly the same issue. So last night after i read the thread, it came to me.
You dont actually need to make any additional holes!!

All that you need is two pipes to go in the normal opening and sealed with a bung. One of the pipes is very short and has a tap, the other is long and goes all the way to the bottom of the carboy.
You fill the carboy as normal, pitch the yeast, put your two pipes in and seal them shut, then turn upside down. A small amount of wort will leak out of the longer pipe but as soon as its upside down, thats it, No more will leak. All you need is a length of soft pipe to attach to it and an airlock or simply immerse in a pot of water. Physics will do the rest....

I have a perfectly shaped carboy which serves me fine, upside down it will be even better and a few hundred quid cheaper than a ss conical!

Time to brew a golden summer ale to celebrate, me thinks.

Cheers fellas

Small edit: i just saw the date on this thread!! (Red face)
 
On your question about the glass tile. Don't hold me to this, but I think your problem is probably in the speed you were drilling. Glass may be different, but when we used diamond core bits to dril 3-6" holes in concrete, the drills we used had very slow rotation. Using a regular drill press probably had too high a speed.
That's my understanding about drilling glass or even ceremic tile -- I had to buy a (get this...) *hand cranked* drill press. Electric drills are too fast and even with water coolant generate too much heat. Hence explosion, is my guess.
 
Also might add here that this site

https://morewinemaking.com/category/glass-plastic-carboys.html
has glass carboys with spigots about 1-2" up from the bottom. (This so annoys me in standard drink dispensers -- you can never get the last bit of punch out!) Not as nifty as a conical carboy but basically the same functionality: use the spigot to rack or bottle off what you'll want to drink, and what's left you can capture or dispose of as you choose. Just not as easy to capture what's left after you've spigoted-off the tasty stuff, but still do-able.

LOL...in the end I went with the glass "Little Big Mouth Bubbler" with spigot:

https://www.northernbrewer.com/prod...ubbler-glass-fermenter?variant=30946904473705
 
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