Romain
Hazard to Self
Posts: 63
Registered: 23-12-2013
Member Is Offline
Mood: Crystallized
|
|
Investing in lab equipment; what to buy?
Hi everybody,
For now my "lab" consists of 5 beakers (2x100 ml, 600 ml, 1l, 2l) and a 500 ml RBF.
I have a budget of about 700 $ to buy some more labware but I don't know what pieces of equipment I should invest in. I mainly
perform small-to-medium scale experiments. (all my reactions fit in a 50ml to 1l flask/beaker/...)
I have a few ideas...
- A set of beakers, erlenmeyers, RBFs, say 50, 100, 250, 500ml and 1l each of each type. Also a 2 and or 3 neck-RBF would be handy. And a few
stoppers...
I'm almost certain I will invest in these.
- A simple distillation setup would be quite useful, to get better purity reagents (for ex. 100% ethanol), and basically everything.
The size would probably be 29/32 because it's the most common size. It would cost about 200 $ for good quality glassware (not Chinese
crap).
- A soxhlet extractor and an Allihn condenser would be useful too but less so than the distillation setup. Still a very nice piece of equipment to
have though. Which size should I pick if I do pick one? I was thinking 100 ml because I would never use more than that amount of solvent in one
reaction and one smaller than that would not be very efficient. That would cost about 200$ for both the condenser and the extractor.
- A vacuum filtration system that would consist of a fritted funnel and a vacuum pump. The problem with this one is that I still need the vacuum pump.
I'll probably scavenge the compressor from an old fridge someday though... it would cost about 70 $ for the funnel and probably add
more than 150 $ for a vacuum pump if I have to buy one.
- A hot plate stirrer. I have a kitchen 1500 W hot plate but you can't regulate the temperature on it and it doesn't stir... I wonder if I should buy
a new IKA hot plate (C-MAG HS7, around 600$ new), or a used one from ebay, or one from another brand?
IKA has a very good reputation and their products are apparently meant to last a long time but they are also very expensive. Is it worth it to invest
in a new hotplate?
If I buy the IKA hotplate new, I won't have much money left (100 $, enough to buy a few beakers and erlenmeyers)
- Maybe a heating mantle?
So what do you think, what is worth spending on and what isn't? If I could, I would buy everything that I mentioned, but here the hot plate is worth
almost all of my budget so I can't afford it plus the rest.
|
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
Some of the bare necessities:
1. A decent 0.01g (or better) scale. You can't do much if you can't weigh anything out!
2. Graduated cylinders. For the same reason as #1.
3. A device for heating and stirring - essential for solution preparation. Even a $20 Walmart hotplate (with temperature control!), and a glass rod
for stirring will be fine to start. Magnetic stirring and a set of various bars is really nice if you have the cash.
4. The containers mentioned in #3. A lot of great packs of beakers and Erlenmeyer flasks can be found online. It is good to get a variety of sizes,
but double up on the ones in the 300-600ml range since you will probably use these the most. Get Erlenmeyer flasks with stoppers for oxidation
sensitive things or stinky solvents.
5. A 1ml class A pasteur pipette and bulb. This is the best $5 you will ever spend. Coupled with the scale, it is an incredibly useful analytical tool
for taking the density of liquid solutions, assessing gravimetrically the solubility of compounds, etc.
6. A partial immersion thermometer, and some closed-end capillaries to go with it. Melting point is also critical in assessing what you have and how
pure it is. You can get a thiele tube if you want but a well-stirred oil or water bath works just as well.
7. A decently-sized (~100mm) porcelain buchner funnel, filter flask, and water aspirator. Waiting hours for things to fall through coffee filters is
annoying, and will ruin compounds that you want to prepare anhydrous, or those that react with oxygen (which there are a surprising number of).
Sometimes you can get the vacuum tap on the funnel and use a regular erlenmeyer to catch the filtrate. Don't bother with a hand pump for vacuum. They
suck.
8. Storage. I started with cheap canning jars. Freund Container and Specialty Bottle are great places to get lots of containers for both solids and
liquids.
You will find that there will be lots more incidental things you need to make your life easier - spatulas, funnels, a mortar and pestle, a torch, pH
paper, a burette, wash bottles, a sep funnel, syringes, pipettes and droppers, test tubes, etc. I would suggest buying these as you see fit. Skip the
expensive stuff to start - I still use plastic spoons from the grocery store and funnels from the auto parts store even though I have glass ones...
simply because glass is expensive, fragile, and not always necessary. If you buy the stuff as you need it, you will eventually end up with a
well-stocked lab.
You may have all of that already though. The next step starts getting expensive, and that is the distillation stuff. This level gets ugly on the
budget really fast.
The best way to start is to pick up a kit. Cheap Chinese distillation kits are worth it. You will break things. Everyone tells themselves that they
are not like the others and they will be very careful, all the time... me included. I still have a glassware graveyard full of newbie mistakes. I
would be much more angry if the broken crap wasn't cheapie glass from China! Shatter your glass, not your bank account. The worst part about Chinaware
is that it takes like 15 days to ship.
I currently have all 24/40 stuff. 24/29 is also common in Chinese glass. I started with 19/22 because I was being cheap... I ended up selling it
shortly thereafter because the stuff was just too small to be useful for anything involving large amounts of solvents or purifying OTC chems, and
19/22 was hard to find apparatus for.
Get a kit corresponding to what your budget allows. A simple 500ml distillation kit with a 300mm leibig will suffice for most purposes. Keep in mind
that if you break just one piece, the whole thing is unusable until you get the replacement part - hence the beauty of bigger kits where you get
multiple condensers, extra flasks, and extra adapters. This is also why it is nice to go with Chinese glass to start. Getting one with a Vigreux
column enables you to fractionate better and you will be able to do a lot more with your kit. Again, get the biggest one that still fits your budget
with some wiggle room for incidentals. I would also suggest picking up at least one multi-neck flask.
Keep in mind that you need to figure out:
1. A heating system for the boiling flask. You can use a hotplate/oil bath/water bath heating system for the flask (which suck!), with a lab jack (or
wood blocks, as I used to do...) so you can remove it from heating if you need to. You will be unable to stir unless the hotplate has a magnetic
stirrer. A heating mantle is better, but you will also need a variac to control the temperature. A 1000mL heating/stirring mantle is ideal for amateur
scale stuff; I have two of them. Unfortunately they are also very expensive.
2. You will need the ability to circulate water through the condenser - It can be a hose on a water tap or a pump in a bucket. Keep this in mind when
you make your budget list. A pump is a lot more expensive than 10 feet of vinyl tubing from the hardware store.
3. Invest in good quality clamps and stands (which are annoyingly expensive!) or you will be like me and break a bunch of glass trying to use homemade
ones.
4. Finally, consider building a fume hood. You may have been able to get away with it up until this point, but boiling stuff inherently involves fumes
- potentially unhealthy, flammable, etc. Now is the time to invest in something that could save your life/house or prevent you from working outside
all the time.
And then there is the miscellaneous junk like joint grease, boiling chips, keck clips, thermometer O-rings, storage flasks with stoppers, addition
funnels, flask brushes, claisen and thermometer adapters, extra stoppers, etc. I won't even get started on chroma columns, microscopes, gas washing,
etc.
I do have a lot of ace/wilmad/kimble/kontes/kimax/pyrex/chemglass stuff but almost all of it is used and was purchased on ebay. I am just now getting
to the point where I can justify the purchase of expensive stuff because I am dealing with some pretty nasty chems, airless chemistry, etc. I wouldn't
worry about glass quality since it's all 3.3 boro glass, Chinese or not, and almost every Chinese place I have bought from will refund for any defect
or breakage in shipping.
Anyway, on top of all of that are the chemicals. If you need OTC sources for chems, I can definitely point you in the right direction.
eBay is the greatest place to get stuff, and Amazon after that. I can point you toward my favorite sellers if you're interested.
I realize that was a bit of a ramble, but I hope it helps a little. If you have any questions about something specific, I will be glad to help!
[Edited on 11-11-2014 by Praxichys]
|
|
|
aga
Forum Drunkard
Posts: 7030
Registered: 25-3-2014
Member Is Offline
|
|
Chinese 'crap' is actually pretty good (usually).
Basically lose that misconception and your $ will go further.
No matter how much you pay for glass, or how great quality it is, it still smashes when you drop it.
If you buy a really expensive hotplate/stirrer, 99.9% likely that the electronics will be Made in China.
First thing is to decide on the Scale you want.
Personally i use 250ml to 500ml vessels mostly, so most of my quickfit joints are 24/29 fittings.
Obviously you can't mix the fitting sizes without adapters, so having them all the same size is convenient.
Essentials :-
1. test tubes + rack
2. Hotplate/Stirrer
3. Stir bars for same
4. 6+ 250ml beakers. All other sizes tend to be empty, all 250ml beakers tend to be in use or dirty
5. Glass stirring rods
6. An excellent glass funnel or two for filtering/general funnelling
7. Distillation rig (Liebig 200 or 300ml condenser, stillhead, rbf)
8. Vac adapter for same (useful even without using vacuum)
9. Water Pump + tubing for same
10. Thermometer
11. Vac pump if you're going to do vac distillations
12. May as well get a buchner filtering setup if you got a vac pump
13. Retort Stand & clamps
14 + 15. If you're into organics, get more RBFs/FBFs and an Allhin condenser too.
Of that lot, 1, 5, 4, 10, 6, 7 are absolutely Essential (in that order).
You can do without, or work around lack of the other items.
e.g. hotplate/stirrer = candles & you stirring a lot.
|
|
|
Loptr
International Hazard
Posts: 1348
Registered: 20-5-2014
Location: USA
Member Is Offline
Mood: Grateful
|
|
I currently have all 19/22 and am a big fan of these guys: http://www.aliexpress.com/store/223140
They sell Synthware brand glassware, and I must say it is very high quality glassware. It is also somewhat easy on the bank account, with the
exception being the shipping.
They have a pretty good selection, too!
|
|
|
Amos
International Hazard
Posts: 1406
Registered: 25-3-2014
Location: Yes
Member Is Offline
Mood: No
|
|
I've gotten pretty much all of my glass from chinese suppliers and have been impressed from the start. Highly-rated stores are rated well for a
reason; people like their products. Instead of paying $200 for a Soxhlet extractor/condenser, why don't you buy a full distillation kit and a soxhlet
extractor from good chinese suppliers (always check for borosilicate 3.3), and have loads of money to spare?
|
|
|
Romain
Hazard to Self
Posts: 63
Registered: 23-12-2013
Member Is Offline
Mood: Crystallized
|
|
Well, thanks for the detailed answers!
I'll probably order the basic glassware first then. I already have test tubes, stands, pipettes, bulbs, a stirring rod, a thermometer, a scale (0.01g)
and a funnel so the next thing to get is a distillation setup (and thus a stand and clamps), more beakers and erlens, graduated glassware and some
storage bottles.
What I meant when I said "Chinese crap" is that my glassware supplier has good quality glassware. I shouldn't have said Chinese, because now that I
think of it, I don't have any examples of bad glassware that is Chinese. I meant to say it wasn't Bomex glassware (which has a bad reputation, though
I haven't tested myself).
One more question, about the hot plate, should I buy a new one or a used one? Have you had good experiences with used lab equipment?
|
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
I have a used Thermolyne Type 1000 heater/stirrer that I got on eBay for $80. The only issue is that the power cord was frayed in one spot, so the
school it belonged to was selling it rather than repairing it.
Of course, that was a very simple fix and it works great.
|
|
|
Dr.Bob
International Hazard
Posts: 2736
Registered: 26-1-2011
Location: USA - NC
Member Is Offline
Mood: No Mood
|
|
As to new or used hotplate, I would not buy a new one from IKA or another big name. While they are great hotplates, you can find good used ones in
good brand names for a fraction of the price, and they will work just as well.
I have both bought and sold (not in the same time periods) used ones for $100 that have worked for years. I will say that good ones last for many
years, but the cheap ones will also, and for $100 you can afford the slight risk that one will break.
But the main issues I have had are cords getting damaged (solvent, heat, and cuts from the sash being closed on them) and for the IKA ones, they seem
to have odd failures (I have seen several give errs that are not trivial to fix), which are not easy to fix. Sometimes the Corning ones don't stir as
well, and often that is due to dirt on the speed sensor. But anyone can fix a Corning , the IKA are more complex. Unless you need really fancy
digital controls, they are much more expensive and harder to fix. I worked for 20 years in chemistry without a single digital hotplate, although I
do like them now, as I have gotten lazier and do more complex chemistry.
|
|
|
greenlight
National Hazard
Posts: 741
Registered: 3-11-2014
Member Is Offline
Mood: Energetic
|
|
Don`t buy a cheap new hotplate, I brought a cheaper chinese model 1000ml RB heating mantle from ebay and it doesnt have low heat after using it four
times, it's either at 100 degrees or off. After the 100 degree mark you can slowly bring up the heat.
Even though its not a heating device, I also brought a used vacuum pump online and have had absolutely no problem with it and it is used fairly often.
I think secondhand is okay as long as it's not a real cheap "never-heard-of-the-name" brand.
[Edited on 13-11-2014 by greenlight]
|
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
@ Greenlight - I had the same thing happen! For some reason, the heat is off until the knob is at about 75%, and then it's basically full blast. I
returned it and they sent me another, which had the same problem. I ended up buying a little temperature controller that I can plug the mantle into. I
leave the mantle on 100% and use the external controller to set the temperature. So far this has worked, but it was a little extra money.
Did you have this one? http://www.cynmar.com/ProductDetail/33049486_Heating-Mantles...
|
|
|
greenlight
National Hazard
Posts: 741
Registered: 3-11-2014
Member Is Offline
Mood: Energetic
|
|
Praxichys, I have the exact same heating mantle as the link you have posted and it does does the same thing you describe. They all must end up having
the same problem from the factory after being used for a while.
An external temperature controller is a good idea and if it means the temperature can be controlled properly again I don't mind spending extra money.
Did you just purchase yours off ebay or buy in a shop.
[Edited on 13-11-2014 by greenlight]
|
|
|
Romain
Hazard to Self
Posts: 63
Registered: 23-12-2013
Member Is Offline
Mood: Crystallized
|
|
Ok then, I'll buy an used IKA (or similar good brand) hotplate!
|
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
I got it at an auction at work for $5. It seems pretty old and I can't seem to find the model online. I believe it is just a wave-chopping type dimmer
switch, rated for 15A.
Basically, like this: http://www.altex.com/AC-Plug-In-Dimmer-Switch-SPST-On-Off-30... except mine has the safety ground.
You could probably make one cheaply with a 2-gang junction box, an old appliance cord, a duplex plug, and a dimmer switch from the hardware store.
|
|
|
Romain
Hazard to Self
Posts: 63
Registered: 23-12-2013
Member Is Offline
Mood: Crystallized
|
|
Praxichys: That's a very good idea, but you still need the stirring and most kitchen hot plates are made of steel, so you can't add a motor and a
magnet to them unfortunately.
Though for a heating mantle, that's perfect and you do not need an expensive variac (which would be a bit overkill)!
|
|
|
Praxichys
International Hazard
Posts: 1063
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline
Mood: Coprecipitated
|
|
Yeah, but when you are just getting started, stirring by hand with a glass rod can save you a lot of money. You could spend the money on other, more
useful apparatus and reagents.
|
|
|
Metacelsus
International Hazard
Posts: 2539
Registered: 26-12-2012
Location: Boston, MA
Member Is Offline
Mood: Double, double, toil and trouble
|
|
You can't stir by hand when distilling, which is a big drawback.
|
|
|
greenlight
National Hazard
Posts: 741
Registered: 3-11-2014
Member Is Offline
Mood: Energetic
|
|
Thanks Praxichys, I will definately buy one of those plug in dimmers.
Did you also notice that during the first few uses the white fibre basket that heats up and holds the round bottom smoked and burnt a bit and turned
brown then stopped after a while.
Just wondering if this is just because its new and a normal thing or another problem.
|
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
