Thanatops1s - 10-8-2013 at 15:27
Anyone know of a decent price on cork rings? Or have any to sell? The prices seem ridiculous for them.
smaerd - 10-8-2013 at 15:29
Could always buy a sheet of cork board and cut some yourself. Might not be as pretty but I'm sure they would work fine. Two layers of concentric
circles tacked together with a small furniture nail would probably do great.
Any excess might still be useful in a lab. Could thumbtack procedures and notes on it out of chemical spill range 
. I use a dry erase board for a similar purpose.
[Edited on 10-8-2013 by smaerd]
plante1999 - 10-8-2013 at 15:49
Buy handicapped people moving machine small tire, remove them and use them as rubber ring.
hyfalcon - 10-8-2013 at 16:24
Plumbing supply has rubber caps that fit over 4" and 6" schedule 40 PVC. They seem to work nicely for me.
Same thing I use on my ball mill to close it up.
[Edited on 11-8-2013 by hyfalcon]
ElizabethGreene - 10-8-2013 at 19:56
Hardware Stores (Home Depot, Lowes, Ace et al.) sell thick manila rope very cheaply. I've found that uncoiling the strands and recoiling them into
rings works well in lieu of proper cork rings.
Would you like me to make a video on the construction process?
Hexavalent - 11-8-2013 at 01:11
Yes please
Thanatops1s - 11-8-2013 at 05:47
Yes, I'd like to see that as well.
I'll have to check Lowes for those rubber pvc caps too.
Praxichys - 11-8-2013 at 06:39
- Empty tape rolls
- Slices of pipe (PVC, cardboard carpet tube, PVC couplers)
- Disposable polypropylene single-serving food containers (gladware, etc.)
- Mason jar lid rings
- A bunched-up towel
- Short food cans (tuna, chicken breast, salmon, water chestnuts, mushrooms, etc.)
Just a short list of all the crap I've used over the years. I usually default to the tape rolls on the lab bench and a towel in the storage cabinet. I
buy super cheap masking tape to label glass with but not much comes on a roll so I use them up constantly. Check your local dollar store.
S.C. Wack - 11-8-2013 at 08:41
Manton cork rings don't seem that expensive. When one attends lab auctions where things are sold by the box, a side benefit is that one tends to get
several of these for next to nothing, along with the other misc. whatnot. The cheap camping-style pans are handy for certain sizes, they can be filled
in for more support and heated for a mantle, and it's cool to have a flask with a handle.
Sheet is the best option, but how best to nicely cut out the cork? IDK if the X-Acto Compass Cutter is up to thick cork or if a typical hole saw (now
these I question why they're so expensive) would give a clean cut. And then there's the bevel...
bfesser - 11-8-2013 at 09:23
Cutting sheet-style cork is a pain in the ass. In my experience, hole saws won't do it (they just tear it to shreds), and an X-Acto® blade
doesn't fare much better. I'd recommend you use one of the substitutes recommended above. However, if we're hell bent on a do-it-yourself solution,
I'll provide a few pointers from experience. First, find a good quality cork sheet. This will be the most difficult part; you'll likely have to test
several before you find one that can be tooled. Second, try sanding rather than cutting or boring. I imagine that a Dremmel® on a high speed
setting with a suitable sanding drum would work quite nicely for this. Perhaps mount the tool in a holder and the laminated cork to a rotating plate
('Lazy Susan' + double-sided tape?) so that you'll get a nice circular shape. You could start with a coarse abrasive drum, but you'll want to work
toward a finer grit for a smooth surface. Third, use a Shop-Vac® for dust control, or do this outside! I have some cork lying around, and am
planning a trip to the surplus shop this afternoon. I have the necessary tools, so I'll try this out and report back.
A side note: <a href="http://en.wikipedia.org/wiki/Cork_(material)" target="_blank">cork</a> <img src="../scipics/_wiki.png" /> is
expensive, regardless of the form. It's soft, springy, non-slip, <em>relatively</em> chemically inert, and thermally insulating (won't
break your flask through thermal shock)—all making for a highly desirable material. Look for cork boards ('bulletin') at office supply
shops, and for cork discs at flower shops (pots are placed on top of them for unknown reasons).
Acidum - 12-8-2013 at 07:11
Friend of mine took hard cardboard cylindrical box of some whiskey, and cut it in several "rings" of about 3 cm, signed them for several of us
colleagues, and we used it extensively during our final years of studies.
Come to think about it, now I must find where did I put it away...
PS
Cardboard maybe sounds terrible for chem lab, but you get to practice not to let contents of your RBF drip all around your work area. And it is quite
resiliant!
Praxichys - 12-8-2013 at 19:49
I found these at the Home Depot today and thought of you.
Thanatops1s - 13-8-2013 at 08:13
^^^^^
Wow, those look absolutely perfect. I'll definitely be going to Home Depot later in the week. Thanks a lot.
95ยข Cork Rings at Ax-Man Surplus
bfesser - 12-9-2013 at 14:47
For anyone in the Twin Cities area; <a href="http://ax-man.com/whereweare/ax1map.html" target="_blank">Ax-Man Surplus on University
Ave.</a> currently has cork rings for 95¢ each! They're the size that holds a 100 mL RBF perfectly (hold 50-250 mL RBFs). Of course,
with the <em>Ax-Man Dozen</em>, you can buy twelve and get the thirteenth free. I don't know if these or perhaps other sizes are
available at the other locations. <em>I'm sharing this knowledge in good faith; don't be greedy! If I find out that any of you buy out the
entire stock, I'll be very angry.</em>
For members not in the Twin Cities, I'd be willing to purchase these on your behalf and ship them to you at cost + shipping + bus fare (2.50 USD per
trip). If anyone's interested, just reply here or PM me with a desired quantity and an approximate address and I'll give an estimate.
[edit] <a href="http://www.ebay.com/sch/Business-Industrial-/12576/i.html?_sac=1&_from=R40&_nkw=cork+ring" target="_blank">Compare
prices</a>, even with shipping and bus fare, this is economical.
[Edited on 12.9.13 by bfesser]
dontasker - 12-9-2013 at 15:47
What? I was there yesterday and I didn't notice them. That's what I get for going there with specific items in mind, but I didn't want to spend
another $100 on random glass, electronics, and doll parts.
Are they in a bin or in the show case thing at the front end of that isle? I won't be able to get back there this week 
bfesser - 12-9-2013 at 17:12
If I recall correctly, they were in a bin, bottom shelf, on the right side of the best <u>a</u>isle (<u>A</u>isle 2? the
glassware <u>a</u>isle), about half-way down, as viewed from the front of the store. I purchased six, and estimate that there were at
least fifty remaining.
If you were there yesterday, we may have passed each other unknowingly. We should really develop a system for SM members to <a
href="https://www.youtube.com/watch?v=ddM7kJ9xQfA" target="_blank">identify each other</a> <img src="../scipics/_yt.png" /> in public.
I've met two other SM members in person, and bumped into one of them again at Ax-Man.
[edit] Knowing that there are at least four of us in the area, perhaps we could set up the first <a
href="http://en.wikipedia.org/wiki/Hackerspace" target="_blank">chemspace</a> <img src="../scipics/_wiki.png" />.
[Edited on 13.9.13 by bfesser]
Finnnicus - 12-9-2013 at 20:26
OT: We need a SCM salute! (/Hand gesture/T-Shirt)
Actually, anyone with a chemistry T-shirt should be approached, and asked if their a SCM member. Very nerdy 
[Edited on 13-9-2013 by Finnnicus]
Variscite - 12-9-2013 at 20:43
Ooh, the idea of a chemspace is extremely appealing to me. The thought of members on SCM collaborating together in real life is cool. I had never
heard of hackerspaces before I read that wiki article, maybe a chemspace could be a thing?
Mailinmypocket - 13-9-2013 at 05:06
Biocurious.org is the closest I can find to a chemistry-space, I'm not nuts about biology but would like to visit the place!
bfesser - 13-9-2013 at 06:14
The hackerspace discussion can be continued <a href="viewthread.php?tid=26163">here</a>.