Sciencemadness Discussion Board

Homemade and Repurposed Lab Gear

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j_sum1 - 13-9-2015 at 16:33

Not deliberately copying pinkhippo1: I also had this idea. I too have constructed a lab jack.
The jack itself was free from a wrecker's yard. I has the melamine shelving lying around (Although I intend at some stage to replace it with a 10mm thick polypropylene chopping board). There are some angle brackets keeping the top steady. Surprisingly, I didn't have anything suitable on my scrap pile. So, for a couple of bucks, plus bolts, I have a 220mm jack that extends from about 100mm to 400mm.

2015-09-13 16.42.31.jpg - 1.1MB

The Volatile Chemist - 14-9-2015 at 13:55

Very nice! Though the picture makes it look rather precarious...

j_sum1 - 10-10-2015 at 15:44

Dead graduated pipette -- chipped on the end and the markings faded off.
I also had a string of 3mm spherical neodymium magnets doing nothing.
Now I have a nice glass stir-bar retriever.

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NedsHead - 11-10-2015 at 00:04

I think we can all guess where this is going

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aga - 11-10-2015 at 00:08

Ball Mill !

Hmm.

That's probably the best way to 'activate' charcoal at low temperatures.

Definitely have to try that.

[Edited on 11-10-2015 by aga]

NedsHead - 11-10-2015 at 00:57

yep, I've wanted one for years and decided its time for action, I should have it finished in a few days, the old 1/4hp motor is a bit overkill but it'll do for now

aga - 11-10-2015 at 06:22

Well, i've been meaning to build one for ages too, and today's attempt at Tin Chloride was a disaster, so guess what i did instead ?

front.JPG - 152kB frame.JPG - 112kB
side.JPG - 166kB

The barrel is a pvc straight coupler with an end cap on one end and a screw cap on the other.

Inside is a straight piece that was cut from some PVC pipe and is held in place by slots cut into the flanges of the end caps, and PVC cement.

The motor is a windscreen wiper motor that is free-running. The wheel on top is from a kids' scooter. The output shaft of the motor had to be extended, so an 8mm thread was drilled/tapped into a 10mm bolt. It isn't perfectly stright & true, but good enough.

Here's a video of it working :

Attachment: working.mp4 (451kB)
This file has been downloaded 434 times

[Edited on 11-10-2015 by aga]

deltaH - 11-10-2015 at 06:30

Very nice!

aga - 11-10-2015 at 14:25

No Ball mill is complete without Balls right ?

To make Lead Balls, you need a Mould.

To make a Mould, you need a suitable material and a tool.

Small Al ingots smelted from scrap were available, so one of those was used.

Pb melts at 327 C, Al at 660 C, so no fear of the Al melting, and Al is so much easier to machine than Steel.

Speaking of Steel, a mild steel Washer is very very round isn't it ?

Also a lot harder than Aluminium, so a washer was welded to a bit of scrap threaded bar, then the edges were ground down with an angle grinder to create a cutting edge on each side.

This tool was used to drill a hemisphere into two parts of the Al ingot, which was then cut in half with a hacksaw.

tools.JPG - 163kB

The two mould halves were clamped together in a small vice and a hole was drilled in the top to allow access.

These were then guaged with a small drill bit poked through the access hole to 'feel' the edges and the halves were tapped into place, then clamped tightly.

Lead was melted in a 40ml porcelain cruicible and poured into the hole until the excess began running over the sides.

Amazingly quick and simple process with just a plumbers' butane blowtorch.

The lead ball can be removed from the mould almost instantly, it cools so fast in Al. .

Result : 5 lead balls ~25mm diameter each weighing 78g +/- 0.2g !!!

Astounding that they are so close in weight given the crude setup and no finishing processing done, apart from chopping off the 'sprue' where the lead went in and some bits where the mould leaks.

balls.JPG - 154kB

For Scale, here they are next to the SM standard reference :-

ballsnbadge.JPG - 170kB

Ball Mill : Done at Last !!

Many thanks to NedsHead for the inspiration.

(a 40ml porcelain cruicible and a pillar drill table were harmed in the making of these balls).

[Edited on 11-10-2015 by aga]

[Edited on 11-10-2015 by aga]

NedsHead - 11-10-2015 at 15:10

Nice work aga! Those mill balls are perfect, I've been racking my brain with what to do about grinding media and was considering buying an expensive length of round stock brass and cutting it up, seeing your success I think I'll give casting lead a go.


aga - 11-10-2015 at 15:18

Go for It !

It certainly works, as you can see.

Avoid using useful Labware for the Melt - use an empty tin can instead.

I need a new cruicible now as i did not heat the porcelain evenly (it broke).

The Mould does not need to be Precise either.

Some gaps just means that you have to (very easily) trim off any excess with wire cutters or scissors.

I wrecked my bench press drill table by over-tightening it when i tried to mill the Al surfaces to make them flatter for a better seal.

Edit:

You Made My Day.

It is very rarely that i can start and finish a project (=happiness) at all (due to the nature of the work i usually do).

Even rarer that a project can be done in 1 day (=Very happy).


[Edited on 11-10-2015 by aga]

j_sum1 - 11-10-2015 at 15:25

Hate to burst your bubble aga. But you didn't consider buying some round fishing sinkers?

aga - 11-10-2015 at 15:38

Entire thing done in 1 day with stuff i already had.

No Shopping (=1 hour round trip, at least. No Point on a Sunday as they are all closed).
No re-moulding pear-shaped sinkers into a more round shape.
No extracting the steel wire intended for nylon fishing line.
No Difficulties at all.

It proves that i can Do It Myself, whether the Shops are open or not.

Enjoyed it all and am happy with the result.

This Bubble is Unburstable.

j_sum1 - 11-10-2015 at 15:52

Yeah. I have a fishing shop five minutes walk away. Open seven days. Most of the lead I have came from there anyway. I may as well buy it spherical if I want spheres.

Not to mention I don't have a spare Al ingot or the ability to weld a washer onto a shaft.
Again an example of what works for one may not work for another.

Nice work btw. Happy milling.


NedsHead - 11-10-2015 at 16:13

Quote: Originally posted by aga  


This Bubble is Unburstable.


Spot on, what you have achieved in a day would have taken me all week!

I'll definitely give casting a try but my biggest problem is I don't have the tooling to make a mould but I have another idea, I can get polystyrene balls of all different sizes from a local arts and crafts shop,

if I were to bury some appropriate sized polystyrene balls in casting sand and bore a small hole leading to each one and pour the molten lead down the hole it should burn up the polystyrene and fill the void, what do you think?

[Edited on 12-10-2015 by NedsHead]

j_sum1 - 11-10-2015 at 16:20

Wax is typically used for investment casting. You can heat up your mould and pour it out. Then cast your metal and break the moulds to get your result. Fiddly, but there are fewer limits on the kinds of shapes that can be cast.

You could try polystyrene and try leaving it in there. Might be messy though. Do in a fume hood.

Oscilllator - 11-10-2015 at 16:31

NedsHead that sounds like a great idea. You've probably heard of it but that method of casting is known to work very well with aluminium (I myself have used it with great success) so I don't see any reason why it wouldn't work using lead.
If you can't find any polystyrene balls though, don't fret - misshapen lumps probably work just as well for the purposes of ball milling. You may even find that they become spherical with time due to wear.

aga - 11-10-2015 at 16:39

As it happens, i have some experience with Casting molten metal ...

If you can get a polystryene ball, just bury it in some sand and pour the lead in (obviously leave a little bit exposed).

Yes, it smells. Not too nasty outdoors, and very brief indeed.

Sand casting is great fun.

Use some talcum powder on the polystyrene ball to get a better finish.

NedsHead - 11-10-2015 at 16:41

My biggest concern is the expanding gasses from the polystyrene may damage the mould, using wax and then heating and pouring it out is a great idea

Edit: thanks aga, I'll try that first

Oscilllator, yeah I've seen this method used for casting aluminium, I hope it works with lead too
[Edited on 12-10-2015 by NedsHead]

[Edited on 12-10-2015 by NedsHead]

nux vomica - 11-10-2015 at 16:58

You could slways buy a sinker mold

download.jpg - 8kB

aga - 12-10-2015 at 00:08

Quote:
My biggest concern is the expanding gasses from the polystyrene may damage the mould


Using the least dense polystyrene ball you can find, the 'mould' is just the loose sand surrounding it.

I have not actually tried this 'investment casting' method with Lead, just Aluminium.

Quote:
You could slways buy a sinker mold


Could always just buy the Mill and the Balls ready made, just not on a Sunday ...

http://www.unitednuclear.com/index.php?main_page=index&c...

nux vomica - 12-10-2015 at 00:38

Just trying to help out aga nobody had mentioned sinker molds , I've made my own ball molds before and a sinker mold is less work to cast the balls,
I get bored after 20 casts and you need 40 to 50 balls at least for the average mill, the sinker mold cuts the time down a lot .
Gives you an excuse to go fishing as well with any extra balls you cast. :)

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[Edited on 12-10-2015 by nux vomica]

aga - 12-10-2015 at 01:21

I definitely need to make one of those.

NedsHead - 12-10-2015 at 04:21

Almost done! I just need to fit some legs underneath and some rubber feet. She isn't pretty but she spins

DSC_1930.jpg - 2.4MB

aga - 12-10-2015 at 08:11

Cool ! What you got for the Barrel ?

NedsHead - 12-10-2015 at 22:40

I found some water tight PVC end caps that have 6 screws and a rubber O ring, I do some reloading and they'll be perfect for wet tumbling dirty brass. This is 100mm PVC with an outside diameter of 150mm so I can also use 150mm PVC with end caps without having to change pulleys.

I also picked up a few packets of ceramic pie weights today from a homemaker shop to try in the mill

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aga - 13-10-2015 at 00:15

Nice work NedsHead !

Being able to use 100mm and 150mm barrels without changing anything is really smart.

Looks like a fairly large rig, judging by the familiar landmark ;)

I guess you could use shorter lengths of Barrel too, so doubly smart !

NedsHead - 13-10-2015 at 00:34

Thanks, I thought the aga scale was necessary;) I have 2 more 100mm end caps for that exact reason, to build a smaller drum for milling black powder and what not.

I'm really happy with how this project turned out

eesakiwi - 20-10-2015 at 22:19

For ball mill media, try ball bearings, roller bearings or used Tungsten carbide machine cutting tips. Like the sort thats used on Lathes and Milling machines.

Roller bearings are a good size and shape. You will find them in machine shop scrapmetal bins, ask first.
Boat builders workshops are great because of the large size bearings they use.

The Tungsten tips are small and very hard, good for grinding stuff apart and finely.

violet sin - 21-10-2015 at 00:28

I'm fairly certain tungsten carbide tips would also eat the barrel material. Early failure could be a bad thing. At the very least you would end up with plastic in you milled product. A rounded, or at least not sharply angular, media would be better in my opinion. Unless you had a liner in there.

One of my rock tumblers has a rubber liner, that protects the plastic from the much harder and often sharply irregular shape rocks come in. Just a thought. I have found steel slingshot ammo pretty affordable and available. Good for milling lump charcoal. Not so effective on other things I tried. Like pollucite.

The Volatile Chemist - 24-10-2015 at 12:36

Are mills ever used in chemistry to grind things? I recently saw a series of messages on a Usenet archive talking about grinding with blenders, but figured mills would be better...

BobD1001 - 24-10-2015 at 13:56

I used my ball mill back when I was involved in high powered rocketry and pyrotechnics. Since I've been more involved in chemistry, I haven't really used it much. However, for making small magnesium chips for the elemental potassium isolation I used my Bridgeport milling machine and a catch box filled with argon, and made a bunch of small passes. Ended up with a huge amount of nearly oxide free pure magnesium chips which worked perfectly for isolating potassium.

BobD1001 - 24-10-2015 at 13:57

Nedshead, are the ceramic pie weights aluminum oxide?

aga - 24-10-2015 at 14:04

My ball mill got built because NedsHead posted a photo.

I'd wanted to build one for ages, simply to grind charcoal and test to see if that made it 'activated' to any extent.

Still not ground any charcoal :(

Work, beer, Other Projects, beer, Life and beer all seem to get in the way of actually accomplishing anything.

[Edited on 24-10-2015 by aga]

JJay - 25-10-2015 at 00:11

Today I was looking around a thrift store for a large aluminum pot, and I noticed that they had several lightweight, folding music stands for sale. They fit my clamps and are sturdy and tall.

SteampunkScientist - 4-11-2015 at 05:19

That is a beautifully made roller, Mr. Head. I wonder though how fast that thing is going to spin with the motor and pulley assembly you have?

Also, I never knew what a "Pie Weight" was until you posted this - now I can ball mill and also make wonderful pastries...

BTW: This is my first post on the forum, so Hello to you all! - I have been a Mad Scientist for years, and have been told that I may actually be quite mad.... :P

[Edited on 4-11-2015 by SteampunkScientist]

NedsHead - 27-12-2015 at 22:55

Something simple today, sauce bottle to wash bottle.

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careysub - 7-1-2016 at 16:03

Quote: Originally posted by Oscilllator  
You've probably heard of it but that method of casting is known to work very well with aluminium (I myself have used it with great success) so I don't see any reason why it wouldn't work using lead.


The above referring to burying polystyrene in sand for an impromptu investment mold.

I predict that it would work less well with lead which is more than four times denser than aluminum. But sand casting is a venerable process, and some sand mold preparation to get firmer support it will work. Look up sand mold casting for details.

JJay - 7-1-2016 at 23:16

I've had luck with

- Dimmer switch instead of a variac - They work fine for most purposes, especially heating. I've found that they often work well with electric motors too.

- Electric drill instead of a mechanical stirrer - While not necessarily the recommended setup for working with flammable or corrosive mixtures, who doesn't have an electric drill?

- Immersion heaters - You'll want to get fairly high wattage ones if you go this route, but they can be used with hotplateless magnetic stirrers with an oil or water bath.

- Mason jars with plastic lids - They seem to be fairly airtight and work well for storing dry inorganic compounds and some solvents.

- 1/4 inch copper tubing - It's useful for connecting destructive distillation crucibles to regular glass condensers.

- Pyrex storage containers - While I don't like to compromise on glass, they work well as crystallization dishes.

- Aluminum pot - I use one to hold most of my heating and cooling baths.

- Music stands - I use them as lab stands. I think it would be easier to use regular retort stands, but they work ok.

- Cheap Walmart hotplate - At 1000 watts of power, it's strong enough for most purposes.

One thing I haven't found a good substitute for is lab clamps.

The Volatile Chemist - 12-1-2016 at 13:39

Arkoma uses wood for lab clamps, which seems a reasonable substitute as it can be cut and formatted easily and is cheap. Some good ideas there, though!

JJay - 13-1-2016 at 10:49

I don't like using wood for lab equipment since it is hard to clean and burns. Also, it is usually impractical to make adjustments to it to accommodate different types of apparatus.

The Volatile Chemist - 13-1-2016 at 14:20

Quote: Originally posted by JJay  
I don't like using wood for lab equipment since it is hard to clean and burns. Also, it is usually impractical to make adjustments to it to accommodate different types of apparatus.

Indeed, I suppose. I use ring stands, but only own two stands, two rings (3"), one screw adapter with nothing to screw into it, and a single-burette clamp.

Zephyr - 13-1-2016 at 14:44

Personally I don't mind using wood equipment, although I always try to varnish them to protect the wood. I find this one is very useful for holding funnels, and plan to varnish it in the next few weeks:

COpvlLq.jpg - 429kB

arkoma - 13-1-2016 at 17:16

Quote: Originally posted by aga  


Work, beer, Other Projects, beer, Life and beer all seem to get in the way of actually accomplishing anything.

[Edited on 24-10-2015 by aga]


Amen brother.

JJay - 13-1-2016 at 20:26

I would think that it should be possible to find suitable clamps and stands at the hardware store, but so far I haven't found any reasonable substitutes just sitting on the shelves.

Detonationology - 13-1-2016 at 21:17

Traditional lab stands have a rod diameter of 3/8" of 9.525mm. It would be fairly simple to pick up some at the hardware and drill into an old 5-10lb barbell weight to mount it along with a liberal amount of epoxy of some sort.

I notice on eBay that the "boss head" clamp holders are dirt cheap from China (~$2.20ea.w/ship.), whereas clamps usually run for ~$8.50ea.w/ship.

I have seen these metal clamps coated with a plastic sleeve of some sort and it resembles many lab clamps sold on the internet, but I have seen these for sale in places like Harbor Freight and Northern Tool for only $1. Perhaps with as simple modification of removing the plastic sleeve and instead use a heat resistant fabric of some sort. My tack welding skills are not the best, especially for small objects, but I'm sure it would be possible to attach a short length of 3/8" rod to the clamp in order to attach it to the boss head clamp holder.

Then, you have everything you need for a stand for nothing compared to what people are charging on the internet.

imgres.jpg - 5kB



[Edited on 1-14-2016 by Detonationology]

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[Edited on 1-14-2016 by Detonationology]

NedsHead - 14-1-2016 at 04:23

Those Chinese boss head clamps you pictured are awful, they're poor aluminium castings and the inside threads are the worst, my distillation kit came with 2, the threads are drilled and taped crooked and a sloppy fit, the aluminium is so soft when you clamp down it strips out the thread, you really do get what you pay for with these cheap Chinese clamps

Detonationology - 14-1-2016 at 04:30

Quote: Originally posted by NedsHead  
you really do get what you pay for with these cheap Chinese clamps.

Thanks for the heads up.

j_sum1 - 14-1-2016 at 04:42

Coming soon...

A stovetop espresso maker converted into a gas-solid reaction vessel to produce a reagent that is not easy to get hold of around here.
I'll leave you guessing. Just ordered a part I need on eBay and so I guess it will be a month before my idea comes to fruition.




Side-note
I have Chinese clamps that look similar to the one pictured. But they are not Al, cost slightly more than what you quoted, and thus far have been reasonable.

NedsHead - 14-1-2016 at 04:57

Very interesting j_sum1... I haven't got a clue what you could be making, I do love my stove top espresso first thing in the morning though

[Edited on 14-1-2016 by NedsHead]

Texium (zts16) - 14-1-2016 at 05:30

A cheap clamp once really put me in danger... I had been melting down some lead to cast an ingot. I had the stainless steel crucible held in a clamp that I thought was steel. Soon after the lead began to melt, I noticed with horror as the clamp bearing the heavy crucible of molten lead began to droop. I shut off the burner and frantically rushed to grab my crucible tongs, but it was too late. The clamp snapped off, and I was only narrowly able to jump out of the way to avoid getting splashed with molten lead. I was picking little bits of lead off the floor and everything else using tweezers for the rest of that day. It left a bumpy black burn mark on my formica lab bench too. Upon inspection of the broken clamp, I realized that it was just some crappy pot metal (likely a zinc alloy) plated with nickel.

Morgan - 14-1-2016 at 08:54

I often wish I had some decent clamps for holding hot things. There are these EMT pipe clamps that come in various sizes and they are certainly not the best/awkward but you can use them if you don't have anything else. By folding some strips of aluminum foil it makes a soft padding for the glassware so the glass isn't scratched up. I guess some silicone matting material would also do for moderately hot clamp padding. And glass cloth or high temperature gasket material could be used.
I got an old T-slot pole that was used for a library magazine rack to attach the EMT pipe clamps to but any T-slot will do. I suppose if given enough thought, you could come up with some sort of nice homemade clamp.
https://www.youtube.com/watch?v=20XcCHnynDY

http://www.pulse-jets.com/phpbb3/download/file.php?id=13716&...
http://www.pulse-jets.com/phpbb3/download/file.php?id=13715&...

Sulaiman - 14-1-2016 at 09:19

If you have the stock and equipment it may be fairly straightforward to fabricate stands and clamps
After two diy attempts I bought new stands and clamps
as the cost is less than buying materials,
if you count transportation / postage.

I bought two types of boss head,
the cheap chrome and blue plastic ones work but give me very little confidence of reliability or safety

The Volatile Chemist - 20-1-2016 at 16:33

Quote: Originally posted by zts16  
A cheap clamp once really put me in danger... I had been melting down some lead to cast an ingot. I had the stainless steel crucible held in a clamp that I thought was steel. Soon after the lead began to melt, I noticed with horror as the clamp bearing the heavy crucible of molten lead began to droop. I shut off the burner and frantically rushed to grab my crucible tongs, but it was too late. The clamp snapped off, and I was only narrowly able to jump out of the way to avoid getting splashed with molten lead. I was picking little bits of lead off the floor and everything else using tweezers for the rest of that day. It left a bumpy black burn mark on my formica lab bench too. Upon inspection of the broken clamp, I realized that it was just some crappy pot metal (likely a zinc alloy) plated with nickel.

That's terrible. I have a few old, nice, really light ring attachments, but my only clamp is from HST, and really low quality. It's impossible to make it stay upright, it always tilts to one side. Also, it's held together with a screw at the clamp part, so the clamp itself rotates side-to-side. I melted the rubber on the clamp, but that of course was my fault.

Morgan - 21-1-2016 at 08:42

Maybe this Turbo Roaster could be repurposed for something. Jam jars are ubiquitous and there're many sizes. And from what I gather it doesn't work as advertised so maybe you could come up with a better function.

https://www.youtube.com/watch?v=pJgT9VecfWw

http://www.ky3.com/news/local/try-before-you-buy-turbo-roast...

Thumbs down reviews
http://wnep.com/2013/11/28/turbo-roaster/

https://www.youtube.com/watch?v=krd1fsm9KHw


[Edited on 22-1-2016 by Morgan]

Detonationology - 3-2-2016 at 16:43

Confirmed:

Candy thermometers are chemistry friendly! As long as the it is completely encapsulated in glass, it is perfectly compatible with strong acids. And it has a very high temperature range.

I found mine in the back of a kitchen drawer, but apparently they are also sold at Wal-Mart. Scrape the glass to test ensure it is indeed completely encapsulated in glass and that the metal on the bottom is not exposed on the outside.

I believe mine had some lead melted into the bottom of the glass in order to give a good place to get temperature readings.



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[Edited on 2-4-2016 by Detonationology]

The Volatile Chemist - 3-2-2016 at 17:38

That's great! I had always wondered about that but never got around to testing the theory they did work well. Many non-scienc-y friends had suggested them when I complained about low thermometer temperatures. How high does that go?

Detonationology - 3-2-2016 at 18:05

200˚C is the max on mine. I also realized that the diameter of glass is narrow enough to fit snuggly in a 24/40 joint with a generous amount of PTFE tape.

JJay - 4-2-2016 at 11:04

I often use candy thermometers for monitoring bath temperatures but have never tried putting them into reagent mixtures.

The Volatile Chemist - 9-2-2016 at 08:42

Quote: Originally posted by JJay  
I often use candy thermometers for monitoring bath temperatures but have never tried putting them into reagent mixtures.

Well, that'd be what I'd use mine for. Perhaps also for the top of a still-head or maybe in a reaction vessel making citrazinic acid...

j_sum1 - 12-2-2016 at 18:18

Nothing that remarkable here but I thought I'd share anyway.

I just used some packing material and a plastic document holder to make a case for all of my thermometers, glass tubes and pipettes. Less chance of breaking them ow and they take up less space since I can stack things on top.
Note the candy thermometer. Idea courtesy of this thread. :)


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Morgan - 12-2-2016 at 18:41

I often use tiny funnels for pouring methanol and happened to notice when trimming the flange of a silicone baby bottle nipple and cutting the tip off that it would work fine as a funnel for some things. And there're probably a lot of other uses, even though the various shapes and sizes of nipples might seem an odd thing to adapt for chemistry or lab applications.
Also the silicone wine bottle stoppers that act as a one-way valve with a vacuum saver seal might be of some odd use. The one I have in front of me has a duckbill valve but there is another design with small holes in a circular pattern.


[Edited on 13-2-2016 by Morgan]

100PercentChemistry - 13-2-2016 at 06:02

Recommend you buy the cd of the golden book of chemistry experiments for 10 bucks. The first chapter is about this. I personally like the close hanger texture holder:D

Detonationology - 14-2-2016 at 07:04

My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of pressure build up.

image.jpeg - 1.1MB

Great - 14-2-2016 at 17:49

Quote: Originally posted by Detonationology  
My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of pressure build up.


The only (mercury) candy thermometers I've seen for sale around here are vintage and not recommended for use. How old is yours?

j_sum1 - 14-2-2016 at 18:00

Quote: Originally posted by 100PercentChemistry  
Recommend you buy the cd of the golden book of chemistry experiments for 10 bucks. The first chapter is about this. I personally like the close hanger texture holder:D

Forget the CD or ten bucks.
Here it is:
http://chemistry.about.com/library/goldenchem.pdf

And in the forum library
http://library.sciencemadness.org/library/books/Brent_GBC.pd...

Detonationology - 14-2-2016 at 18:17

Quote: Originally posted by Great  
Quote: Originally posted by Detonationology  
My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of pressure build up.


The only (mercury) candy thermometers I've seen for sale around here are vintage and not recommended for use. How old is yours?

Mercury? Good God, I couldn't possibly imagine it anywhere near food. Mine has a red liquid, likely alcohol or ethyl acetate, and has to be at least 20 years old.

violet sin - 14-2-2016 at 18:28

@ great: Pretty sure that is a weighted shot in the bottom, with a standard alcohol thermometer in/on it. I've seen a few that had little lead shot looking pellets at the tip, with a drop of wax/glue seating them. Guess it's steel shot from some quick reading from disgruntled brewers on Amazon.

Detonationology - 14-2-2016 at 18:40

Yeah, I think it is lead in the bottom. It was likely poured into the pre-heated glass tube, then the actual thermometer part was placed down into the molten lead to give a good, thermally conductive location to receive temperature readings.

The Volatile Chemist - 22-2-2016 at 15:47

Are there even mercury thermometers for sale now?

j_sum1 - 22-2-2016 at 16:29

I bought one recently.
(It's pretty useless since the graduations are so faint they can't be seen easily. I got a refund.)

Yay!! Free gram of mercury!

hyfalcon - 23-2-2016 at 06:09

Take a black marker and you can temporarily at least re-blacken your graduations.

nux vomica - 6-3-2016 at 15:48

If anyone is interested in a cheap and easy made flask heater I've been trying out a version that uses a 2000 watt heat gun as the heating source.

It's made out of off cuts from work , the main barrel is 4" s/s tube 3" high, the rest is to suit the gun and mount the support tube ,there is a perf s/s disc inside the barrel to support the flask when you are setting up and to diffuse the hot air.

I use a triac voltage controller to vary the fan speed and temperature and it will boil 250 mls of water in under 5 minutes
Cheers nux.

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[Edited on 7-3-2016 by nux vomica]

NedsHead - 11-3-2016 at 00:59

I was unable to find the type of rubber stopper used with wide mouth vacuum flasks (probably because I don't know what they are called) so I cut a hole in a rubber stopper for furniture legs I found in a hardware store, the fit is nice and tight, I can lift the whole apparatus by the buchner funnel, not that I will of course.

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gerarddekker - 11-3-2016 at 02:23

Setting up my own lab. Great ideas here. Thanks all.:cool:

arkoma - 11-3-2016 at 09:59

Quote: Originally posted by 100PercentChemistry  
Recommend you buy the cd of the golden book of chemistry experiments for 10 bucks. The first chapter is about this. I personally like the close hanger texture holder:D


The book is available in the SM Library (Kudos to Annaandherdad)


I forgot my camera today, but I am getting further use out of parts from the Bunn-O-Matic coffee maker my store owner friend gave me.

1) First off, I swapped the burners around and have a two burner warmer,

2) The stainless steel screen that the water used to get poured through powders cottonwood charcoal WONDERFULLY, and I make it with,

3) The hot water reservoir is stainless steel and about 16 inches tall and a paint can lid fits over the top nicely. I pack it with cottonwood twigs and wire paint can lid on and then toss whole assembly on a fire in my backyard--when smoke quits coming out I have wonderful softwood charcoal that makes EXCELLENT black powder.

4) The filter basket has three little plastic lugs on the bottom that allow it to sit on a counter--they also fit PERFECTLY the inside diameter of my 250ml beakers for painless gravity filtrations.

The Volatile Chemist - 13-3-2016 at 15:57

Gas bubbler from Vacuum filtration flask, Vacuum stopper, test-tube stopper with a hole, and a very long pipette - one of my favorite innovations in regards to glassware. Also, using a vacuum filtration flask as the receiving vessel for an otherwise sealed distillation rig, allowing for vacuum pump attachment to a non-ground-glass distillation set-up...

quantumcorespacealchemyst - 23-3-2016 at 10:05

Quote: Originally posted by nux vomica  
If anyone is interested in a cheap and easy made flask heater I've been trying out a version that uses a 2000 watt heat gun as the heating source.

It's made out of off cuts from work , the main barrel is 4" s/s tube 3" high, the rest is to suit the gun and mount the support tube ,there is a perf s/s disc inside the barrel to support the flask when you are setting up and to diffuse the hot air.

I use a triac voltage controller to vary the fan speed and temperature and it will boil 250 mls of water in under 5 minutes
Cheers nux.



[Edited on 7-3-2016 by nux vomica]


that's great! i also think you can use a toaster oven with the door turned vertical with a opening in the door. there's a black and decker 4 slice toaster oven/fits a 9'' pizza for like $30 at walmart. it seems like it can fit most 14/20 glass but for 24/40, maybe 19/22, and up perhaps a larger toaster oven is more appropriate.

the one i mentioned has two radiant heat tubes which are of the clear/translucent type, with no air flow. the larger types, like an oster oven, have some of those heating elements that look like carbon/graphite rods. i don't know which ones are more effective. the plus side of the oster oven i saw for around $60, i think, was that it had 4 elements so the flask would be surrounded by radiant heat, there was also a fan, so the air would circulate as well (only on one side though, so it would maybe heat one side of the flask unevenly). that could be modified though, probably. the plus side of a toaster oven seems to be the efficiency, and the temperature control. i got the black and decker one to try my hand at hacking a mantle together, before messing with microwaves, as it seems a better first step, with the microwave/electromagnetic wave shielding , and temperature control issues that could be encountered with it (although i guess that certain reactions depend on the microwaves themselves for reacting.). you can supposedly get up to 450degreesF (232.222degrees Celcius) with the pizza oven. i just saw that heat guns can get to like 800degrees Celcius, so i guess the heat guns are better, but not as efficient. i guess making a kiln oven/mantle with a temperature sensor/controller would be ideal.



also volatile chemist,
http://www.ebay.com/itm/Glass-Celsius-thermometer-0-500-degr...
to 500degrees Celcius!!!

and

http://www.ebay.com/itm/Glass-Celsius-thermometer-0-300-degr...

to 300degrees Celcius

Magpie - 24-3-2016 at 15:41

Here's a simple idea for cheap weigh boats. I grabbed these muffin papers when my wife wasn't looking::D



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CharlieA - 24-3-2016 at 17:57

That is the epitome of "Why didn't I think of that?"! Good show.

NedsHead - 24-3-2016 at 21:21

My wife had the same problem Magpie, now when she needs them she buys 2 packets, your wife will catch on too

brubei - 25-3-2016 at 01:08

filtration for less than 15€, no problem of corrosion or flammability.

20160325_100125 - Copie.jpg - 232kB

Sulaiman - 25-3-2016 at 07:10

Aspirator, flask and funnel for 15 euro ?
where ... I want one.

brubei - 25-3-2016 at 07:28

Sorry, I talked about the vaccum system :D instead the use of electric pump wich can be damaged by solvent or gaz


[Edited on 25-3-2016 by brubei]

Arbetarn - 30-3-2016 at 07:50

Anybody has an idea on how to make a solvent stillhead?

chemrox - 30-3-2016 at 13:58

What is a "close hanger?" Literacy issues annoy me. Anyway-new subject: I'm thinking of using a soxhlet for slow addition to a boiling solution. An alternative would be an addition funnel with glass wool at the outlet. Or wrapping the material (solid solution) in filter paper (thanks Bob). But the ideal apparatus would be a soxhlet modified so as to not siphon i.e. straight through. I have several soxhlets and one is about the right size. Here's the problem; I would have to collapse the siphon tube. I'm afraid of the delta-T cracking the apparatus.
edited to correct misspelling

[Edited on 30-3-2016 by chemrox]

j_sum1 - 31-3-2016 at 23:22

I just worked out that I can jury-rig an acceptable approximation to a Dean-Stark trap using the glassware I already have with the addition of a male-male ground glass adapter.

From the bottom:
Regular flask
Male-male connector
Claisen adapter (upside down, curved sidearm portion attached to previous part)
Reflux condenser (probably a liebig) again upside down

Lower straight through portion of claisen can have a regular straight through stopcock attached.

This setup has three joints orientated upside down so I would grease properly and use keck clips. But, hey, nice to know it can be done.

100PercentChemistry - 1-4-2016 at 07:06

The cd version(8 dollars on Amazon) of the golden book if chemsitry experiments has a section on homemade lab gear.

The Volatile Chemist - 9-4-2016 at 17:40

The Annotated Do It Yourself Science Laboratory is a pretty good resource too.

100PercentChemistry - 10-4-2016 at 12:55

A ring stand with a clamp can be a good camera holder if you don't have one.

battoussai114 - 10-4-2016 at 14:10

Quote: Originally posted by 100PercentChemistry  
A ring stand with a clamp can be a good camera holder if you don't have one.

Remember: there is no commutativity in lab gear, a camera holder can't be a good ring stand with clamp. :P

Imporvised Buchner Funnel

RogueRose - 3-5-2016 at 16:58

I need something I can use for vacuum filtration and a Buchner funnel the size I need is kind of pricey and I have a tendency to break things I need so I came up with an idea I want to run by you guys to see if it should work.

I took a 3" CPVC endcap (hole size is 3.5" actually) and drilled some holes in 1/16" ABS sheet that is cut to sit in the endcap. The endcap has a ledge about 1/8" from where the curvature starts on the end and the filter plate sits on this. I am not certain if I need to glue the plate to the cap but I suspect I will get better results should I do this.


Now the cap has no hole in the end ATM but I plan on drilling a hole and putting a plastic nipple on it sunk into the plastic. As the end is concave, a hole in the center, counter-sunk, should allow liquid to flow down the hole easily. A hose (4-12") will attach to the collection vessel which is an air-tight pipe with a port to connect the vacuum.


Now my biggest question is the capacity of the funnel. Curently there is about 300-350ml capacity using just the endcap. I can glue on a container to act as a larger holding resevoir but I'm not sure if that causes a problem with filtering solids (large mass blocking vacuum filtration..?)



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j_sum1 - 3-5-2016 at 17:11

Leaving it unglued makes for easier cleaning. I would leave it like that if it functions ok.
Looks like a good bit of gear. Drilling of all those holes looks tedious. I see no reason why your plan wouldn't work -- subject to the limitations of PVC as a material of course.

XeonTheMGPony - 3-5-2016 at 17:14

great idea. very nice work.

As to the depth theoretically there is no limit depending on how long and powerful the vacuum pump is, but for practicability I'd wager there is a formula for the bottom surface area per given height.

For simplicities sake, I'd leave it as is and divide the batches.

for your next one I'd keep the holes centered around the middle and leave more dead space around the outer edges say 5 to 10mm or so.

Ozone - 3-5-2016 at 17:33

Pretty cool. Avoid holes at the edges, though. These will allow for channeling of sample through a paper or celite pre-coat. I'd also watch the size of the holes. If they are too big, your paper will suck through them and break.

If you want to semi-temporarily seat your filter support (and seal those holes at the edges), some RTV silicone would work well (it's fairly inert when cured, stable at higher temperatures for hot-filtration, and can be cut loose with a blade).

O3

[Edited on 4-5-2016 by Ozone]

RogueRose - 3-5-2016 at 19:10

Thanks for the replies. I plan on filling in the outer holes with some glue of some type. I drilled them out before I knew the inner diameter of the circle so all in all, I stayed pretty well inside of the outer perimeter!

The holes took about 15 mins to drill with one of those electric screwdrivers with a chuck bit attached.

I'm thinking of adding an O-ring to either the plate or the bottom ring of the end cap. If I can make it perfectly flat I should be able to remove the plates yet allow them to seal well when in place.

[Edited on 4-5-2016 by RogueRose]

Daffodile - 3-5-2016 at 19:14

I did this with a cut off soda bottle and a yogurt container, the biggest problem is connecting the body with the 'sieve'. Leaks open constantly, epoxy is the shit.

Dr.Bob - 4-5-2016 at 03:59

That is a neat idea, and might be good for teachers who need lots of cheap simple apparatus. They will be fine with water but not many organic solvents, as even methanol will leach out the plasticizers from PVC.

They do sell plastic buchners, I have found a few over the years, but they are made of polypropylene or polyethylene, so those will stand up well to solvents, unlike PVC. It is always nice to make your own stuff, but for some things, there are already really inexpensive solutions. And real Buchner funnels are actually pretty inexpensive, especially used, but they are heavy and thus pricey to ship, and break if dropped.

CharlieA - 4-5-2016 at 13:39

Clever idea Rose! You might try to find a polypropylene or HDPE bottle to modify. For example, milk bottles are HDPE, although the wall thickness is small. The RTV silicone also sounds like a good idea. Let us know how your funnels work.

careysub - 4-5-2016 at 14:27

Quote: Originally posted by RogueRose  
I plan on filling in the outer holes with some glue of some type.


What you want to do, to fill in holes, is glue a piece of PVC over them with PVC cement, or else dissolve PVC into PVC cement until it won't dissolve any more, then fill the hole with that.

PVC, when cemented together, forms a single PVC piece as solid as if it came from a factory that way.

PVC is a low surface energy material (only twice that of Teflon) and glues hardly stick to it at all, unless you flame treat it (pass a propane flame over so that the shiny surface turns dull temporarily).

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