Watch Glass Size question.

[jack_burton]

What size watch glass is most suitable for 5000ml low form beaker?

 

[niteliteone]

I usually measure the size of the beaker and buy one that is larger than the measured beaker.

Tom C.

 

[jack_burton]

The problem with that for me being I'm ordering online and don't have access to the beaker at the moment.

 

[niteliteone]

Usually when I buy glassware online the seller lists the sizes of the glassware.

What brand and model number are you looking to buy?
I'll try to find out the sizes if I can.

Tom C.

Edit to add:
found this one which would use a 200mm (20cm) watchglass
Size: 28cm x 18cm (10.75 x 7.25")
Capacity: 5000ml or 176oz
http://www.lotioncrafter.com/borosilicate-beaker-5000ml.html

 

[jeneje]

What is a watch glass? and what is it used for? I have heard the term mentioned here before but i have not seen one.
Ken

 

[jack_burton]

Thank Tom, the 200mm basically answered my question.

Ken- watch glass covers the top of a beaker while you are heating liquid within. Keeps excess vapor from escaping and funnels condensation back into the beaker. Here's a link to a picture of various sized ones:
https://www.avogadro-lab-supply.com/item_images/Watch%20Glass.jpg

 

[niteliteone]

JB,
I looked at several different manufactures and they were all about the same size. The 200mm will work fine and I bought all of mine from avogadro lab supply. Very nice, no imperfections and nice flame polished edges. Good price too.

Glad to help
Tom C.

 

[jeneje]

Thank Tom, the 200mm basically answered my question.

Ken- watch glass covers the top of a beaker while you are heating liquid within. Keeps excess vapor from escaping and funnels condensation back into the beaker. Here's a link to a picture of various sized ones:
https://www.avogadro-lab-supply.com/item_images/Watch%20Glass.jpg

Thanks Jack, I will need some of those when i heat AR for my nect project, MCC's
Ken

 

[goldenchild]

You could use a normal glass saucer if you wanted.

 

[Palladium]

This guy here seems to be having a fire sale on watch glasses.
http://www.ebay.com/sch/Healthcare-Lab-Life-Science-/11815/i.html?_catref=1&_ssn=mikesnewandused1&_trksid=p3911.c0.m1538

 

[Harold_V]

You could use a normal glass saucer if you wanted.

Two obvious problems. One is a saucer may not be tolerant of being heated. The other problem is density. A heavy glass saucer is likley to break a beaker if there's any bumping.

Watch glasses aren't cheap, but they're much cheaper than losing values or expensive lab ware.

Harold

 

[The Refiner49er]

Hi All-

I can't resist posting here, simply as information to save GRF members some of their hard earned money. I have been using tupperware bowl containers with the rounded or tapered bottoms in various sizes for several years that fit well over (or rather into) the beakers as covers, they seem to be effective and I often fill these partially with water or ice to encourage condensation on the inner surface when this effect is desired.

Being made of HDPE, they are acid resistant but do have a lifespan in which they become brittle, but no real loss as they are very cheap if purchased at a thrift store; sometimes the lids work equally as well upside down, so one set= two covers.

Also, thanks for any links for buying watch glass covers, especially the better deals!

 

[Palladium]

I bought 1 dozen 6" watch glasses for $13 including shipping.
http://www.ebay.com/itm/220948962603?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 

[Barren Realms 007]

I bought 1 dozen 6" watch glasses for $13 including shipping.
http://www.ebay.com/itm/220948962603?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I bought some of his 3", 4" & 6" they arrived very fast and in good shape, he did a good job of packing them.

 

[Palladium]

I bought 1 dozen 6" watch glasses for $13 including shipping.
http://www.ebay.com/itm/220948962603?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I bought some of his 3", 4" & 6" they arrived very fast and in good shape, he did a good job of packing them.

Got mine today. Fast shipping and they were in the box packed between two pieces of polystyrene and wrapped with bubble wrap.