sourcing a sight glass and another Q

[trial&error]

as the title says, how are you sourcing or building a sight glass to add to the condenser and column.


ever add "heating chips" like in a chemistry lab. they add ceramic chip/bar/ pellets in the liquid for....not sure.... to help even out the heat?

[mrhooch]

Heating chips are used to give a place where bubbles form when you are boiling a wash. They give a more even stream of vapour bubbles rather than a couple of big ones.

I built my own sight glass after I saw the price of new ones.

I took a 3/4 union, use the side where the nut screws on to. File or grind the pipe fitting side flatter as it has a flared or angled end for a better seal. Cut a round piece of glass, to fit inside the nut part, make two rubber gaskets, Homeless depot sells large rubber washers, I used a large hole punch to make the center hole, and assemble it. If you want a larger one, you can use of of those slip couplings in copper you use for drainage and do the same thing.

Hooch.

[rad14701]

mrhooch, don't you see rubber gaskets as a problem with high temperature high %ABV alcohol...??? Is this a "special rubber" or just "plain old rubber"...??? Neat idea, aside from the "rubber"...

[mrhooch]

Well my sight glass was for my coffee maker still and isn't in the high ABV path. If I was going to put it at the top of my still, then I would have to rethink the gasket material, perhaps an o ring of viton or some food grade material that is meant to handle very nasty chemicals.

Hooch.

[rad14701]

Ahh... Yes, a wash level sightglass is another story altogether... However, trial&error is looking for a product sightglass which falls within my original concern...

[Whitedog]

There are 5 grades of Viton and I cannot find where any of them are rated for high temp, high ABV....

[mrhooch]

I whole heartedly agre with avoiding plastics and in fact most materials in the vapour section of your still head. Wierd stuff happens, and then you don't know what you are really drinking.

I didn't research viton seals for this application, it is a material that we always specified for o-rings and such that were intended for higher temps and severe usage, rather than neoprene. There may be something else that may be more appropriate.

Perhaps teflon? I know you can get it in a variety of shapes and sizes. In sheet form, you could cut a gasket from it.

My only concern would be that the co-efficients of thermal expansion of copper and glass are sufficiently different that it might cause the glass to break. In the vapour path, a nicely lapped surface could have enough of a seal to use glass right against the copper.

But it all depends on how big a sight glass he wants.

Hooch.

[trial&error]

humm
well i had i few ideas, get a threaded cap (brass or copper) drill/mill out the middle, cut 2 cork board gaskets, and sandwich the glass and put in the cap then thread on....
looking at different pieces of copper to make one and found these
http://www.aircomparts-air-compressors. ... nucolumn=7
$7-13
http://www.flowfitonline.com/acatalog/ ... ="nofollow

TF050101AV
http://www.jackssmallengines.com/camp_aircomp_hp.cfm

[Dnderhead]

I have one with cork,never bothers unless it sits idle for a month or so then it tends to dry out.

[olddog]

How do you manage to cut the glass discs so small

OD

[rednose]

circle glass cutter:

[rednose]

This is a draft of a commercial sight glass:

This is an universal 2" SS joint (the part that will be replaced by 6mm glass is on the left side), do you see what I mean?:

You can make some rounds on the glass edge with cheap teflon tape or use this excellent material:
http://www.chesterton.com/ENU/Products/ ... odelID=185" onclick="window.open(this.href);return false;" rel="nofollow

BTW: That are homemade Solar panels where the fitting is sitting on.

[olddog]

Did you cut the glasses yourself with that glass cutter Joe?

OD

[rednose]

No OD, I use a diamond cup cutter which has inside excactly the diameter I need.

But you can do it, a friend of mine has a glass shop and he use this thing for small diameters.

[olddog]

No OD, I use a diamond cup cutter which has inside excactly the diameter I need.

You mean like this

80.jpg (1.9 KiB) Viewed 6741 times

OD

[rednose]

Yep, but bigger size.

No OD, I use a diamond cup cutter which has inside excactly the diameter I need.

You mean like this

80.jpg

OD

[rednose]

This is how it's loking after machining it.

Took me two hours including to have a beer with my friend who owns the metal mechanic.

A good mechanik can do it in less than an hour (and better) I guess.

[ozone39]

I run a sight glass tube for my gin still. I used a 5/8" O.D sight glass tube for a water level tube on a steam boiler. This tube fits perfectly into a brass 5/8" compression 90 (or tee). Pull the brass ferule out slide it over the tube and wrap it with 4 to 5 wraps of teflon tape. Install tube into fitting and snug tighten the compression nut. Work great...

[trial&error]

can i use regular window glass for the a sight glass?

[rednose]

I asked glassman in a PM and he secured me that it is ok to use normal window glass (he uses 4mm) but it don't have to touch metal nowhere.

So that's what I use but I didn't run (test drive) it till now.

can i use regular window glass for the a sight glass?

[trial&error]

humm.... i had a house window break and saved a huge piece of glass for a sight class....

[rednose]

I'm using 6mm glass but my sight glass is 3" wide, like to be on the secure side.

Anyhow I'll test drive it with water which are harder conditions than with alcohol.

Also will give it a bad time while testing, like spraying cold water on it etc.

Once that I see it survives all bad treatment I'll give it a real run.

humm.... i had a house window break and saved a huge piece of glass for a sight class....

[Whitedog]

Rednose,
Here is how they temper or toughen glass... dont know if you have a means to do this but it would help ensure you glass will "cut the mustard".

Tempered glass is about four times stronger than "ordinary," or annealed, glass.Toughened or tempered glass is used when strength, thermal resistance and safety are important considerations. And unlike annealed glass, which can shatter into jagged shards when broken, tempered glass fractures into small, relatively harmless pieces. As a result, tempered glass is used in those environments where human safety is an issue. Applications include side and rear windows in vehicles, entrance doors, shower and tub enclosures, racquetball courts, patio furniture, microwave ovens and skylights.

To prepare glass for the tempering process, it must first be cut to the desired size. (Strength reductions or product failure can occur if any fabrication operations, such as etching or edging, take place after heat treatment or annealing.) The glass is then examined for imperfections that could cause breakage at any step during tempering. An abrasive, such as sandpaper, takes sharp edges off the glass, which is subsequently washed.

Next, the glass begins a heat treatment process in which it travels through a tempering oven, either in a batch or continuous feed. The oven heats the glass to a temperature of more than 600 degrees Celsius. (The industry standard is 620 degrees Celsius.) The glass then undergoes a high-pressure cooling procedure called "quenching." During this process, which lasts just seconds, high-pressure air blasts the surface of the glass from an array of nozzles in varying positions. Quenching cools the outer surfaces of the glass much more quickly than the center. As the center of the glass cools, it tries to pull back from the outer surfaces. As a result, the center remains in tension, and the outer surfaces go into compression, which gives tempered glass its strength.

Hope this helps... WD

[rednose]

Thanks for the info whitedog

That will be the last option if normal 6mm glass doesn't resist but here are companies who temper and it's very cheap so DIY efforts with the risk that it'll not work is out of question for me.

Joe

[ozone39]

how about installing a piece of pyrex pipe in there somehow???

[rednose]

I don't get you ozone, what you want to do with a pipe there?

It's a window to observe the actions inside the column.

Pyrex would be fine as a material but I hadn't have the luck to find a plane pyrex glass.

how about installing a piece of pyrex pipe in there somehow???

[olddog]

how about something like this.
http://cgi.ebay.com.au/10-x-LG1175-70mm ... 35a70cc901" onclick="window.open(this.href);return false;" rel="nofollow

They have various sizes available


OD

[ozone39]

I was thinking a guy could put a piece of pirex pipe (glass pipe) in the column, and be utilized as a 360 degree visible sight glass. Just thinking outside the box a little....Or you can just go to St.Patricks.com and get one of these:

[rednose]

No way, read what stpats say:

Max temperature 150° F
Much too risky

....Or you can just go to St.Patricks.com and get one of these:

[Ayay]

I tried to cut a sheet of glass that was the bed of a scanner. Scored a line and tried to break it over the edge of a table. Pushed harder and harder...really tough, it flexed a lot, then POW the whole sheet exploded into a million crumbs!

After reading WD's earlier post I now know it was tempered glass