Sciencemadness Discussion Board

Help modifying a retail microwave for lab use

Stupid_Noob - 8-11-2014 at 06:04

I want to use the unit for MAEs, distillations, etc. I have ideas on how to go about cutting a hole in the top of it, but if anyone can assist, I sure would appreciate it.

Specs:
Sharp Carousel model R-520LK-T
1200W power
16" glass turntable
24"W x 13 3/8"H x 19 1/8"D

The thing is big and powerful. I dont want to fuck up a perfectly good microwave by just hacking a big hole in the top. I haven't taken it apart yet but I will soon. I'll get back to this in a few.

Stupid_Noob - 8-11-2014 at 06:31

Ok, so far I can't even get the metal housing off the damn thing. There are a pair of screws on the bottom of the unit that are some weird hex-type screw but the center of the screw head has a rounded protrusion that makes it so a normal allen won't fit it...

Ideas?

[Edited on 11-8-2014 by Stupid_Noob]

Chemosynthesis - 8-11-2014 at 06:33

areBest to use the search function and continue relevant threads.

http://www.sciencemadness.org/talk/viewthread.php?tid=4918
HTTPS available
https://www.sciencemadness.org/whisper/viewthread.php?tid=49...

There aare at least two others. Anyway, you probably need a tamper proof bit to mess around in the housing, if that's what you want to do.

[Edited on 8-11-2014 by Chemosynthesis]

Stupid_Noob - 8-11-2014 at 08:23

Yeah... TFSE is just about useless for me. I learned a couple things, like just hacking a hole in the top and jamming a column through it is a good way to microwave yourself.

From what I've read, it will be cheaper/safer/smarter to just use traditional heating methods.

aga - 8-11-2014 at 09:49

ISTR that the cavity is shielded (and tuned ?) to prevent the microwaves escaping.

The mesh in the glass door is of a specific size to act as a choke to the RF energy, preventing it leaving in significant quantity.

Hacking a big hole in the top may impact negatively on the design parameters ...

Why a Hole anyway ?

I thought that the idea with microwaves was to radically shorten the Time required for heating a reaction, and was done in bursts of say 30 seconds each time, between which you can open the door.

Stupid_Noob - 8-11-2014 at 12:50

Quote: Originally posted by aga  
ISTR that the cavity is shielded (and tuned ?) to prevent the microwaves escaping.

The mesh in the glass door is of a specific size to act as a choke to the RF energy, preventing it leaving in significant quantity.

Hacking a big hole in the top may impact negatively on the design parameters ...

Why a Hole anyway ?

I thought that the idea with microwaves was to radically shorten the Time required for heating a reaction, and was done in bursts of say 30 seconds each time, between which you can open the door.


I am not well versed in microwave chemistry... I was under the assumption that it could be modified so a vigreux or similar would fit through a hole in the top, connecting a distillation flask inside the chamber to the condenser outside... I figured that the microwave was then run at reduced power to offer a means of flame/spark-free heating.

Hey, it sounded good in my head.

aga - 8-11-2014 at 13:50

I think the idea is to whack energy into the reaction faster, so as to reduce reaction time.

(any expert on Microwave chemistry please jump in here with a proper explanation.)

For a Distillation with a Vigreux, a slower distillation will yield better product anyway, so microwave techniques would not be helpful.

Chemosynthesis - 8-11-2014 at 15:11

Quote: Originally posted by Stupid_Noob  
Yeah... TFSE is just about useless for me. I learned a couple things, like just hacking a hole in the top and jamming a column through it is a good way to microwave yourself.

From what I've read, it will be cheaper/safer/smarter to just use traditional heating methods.

There are a couple other threads, including one I commented on and more lit which answers some questions you seem to have, but the other issue is to post in existing threads so as not to clutter the forum and necessitate more searching... not just your edification:

https://www.sciencemadness.org/whisper/viewthread.php?tid=41...

https://www.sciencemadness.org/whisper/viewthread.php?tid=35...

What were you interested in refluxing? It might not require a long column or enclosure.
I'm assuming, since you are ignoring my post, that it's related to your L-PAC spoonfeeding request to synthesize ephedrine/pseudoephedrine, and ultimately methamphetamine from yeast.

[Edited on 9-11-2014 by Chemosynthesis]

Little_Ghost_again - 8-11-2014 at 15:24

If you go the microwave route I would vote you buy a cheap microwave leak detector, they dont cost much but could save you toasting parts you prefer to keep raw!
I know someone who uses a modified MWO and they put a bowl of water on top to absorb the leak they have, I really dont recommend it though. I mess with electronics a fair bit and have messed with the transformers from them, but the magnatron in a modern microwave isnt something to take risks with, it really dosnt take much to cook an eyeball with microwave radiation.
Please be careful with these things, the screws you mention can be undone with cheap security screwdriver sets from ebay, generally the harder the screw is to undo the more dangerous the equipment your messing with :D

Stupid_Noob - 8-11-2014 at 16:07

Quote: Originally posted by Little_Ghost_again  
If you go the microwave route I would vote you buy a cheap microwave leak detector, they dont cost much but could save you toasting parts you prefer to keep raw!
I know someone who uses a modified MWO and they put a bowl of water on top to absorb the leak they have, I really dont recommend it though. I mess with electronics a fair bit and have messed with the transformers from them, but the magnatron in a modern microwave isnt something to take risks with, it really dosnt take much to cook an eyeball with microwave radiation.
Please be careful with these things, the screws you mention can be undone with cheap security screwdriver sets from ebay, generally the harder the screw is to undo the more dangerous the equipment your messing with :D


Yeah I've abandoned this idea. There is a far greater chance of me seriously fucking myself up than ever benefiting enough to be worth the hassle/danger/cost. Ill stick with my crappy stirrer/hotplate.