idbruce um i need to agree with the microwaves is bad, crowd as a former hobby playing with MW they are funny, unpredictable, and dangerous.
water vibrates when exposed to MW thats what mostly heats the food.
and used right MW can even chill. but, unless you are prepared for the microwave to go skyhigh please don't try it.
I have seen a few people get a trip to the ER over trying to use MW in other ways.
one of them put an object with a metal rod in and the rod focused the MWs out and he actually cooked his own chest! serious where the rod pointed at was killed about 2 inches deep.
marble may explode, refocus the MWs or if the crystal structures on the stone is right it could act like a ceramic capacitor inducting the MWs into a stored voltage and when you get close ZAP like a bug.
just plz believe me on this, MWs = danger be careful.
Also, microwave ovens can be damaged by running them with an incorrect load like an empty glass.
I forgot all about that.
One thing that I am learning the hard way is that if you apply a specified temperature to a target and you want that target to be the same temperature, the heating process is very slow.
I think the ideal process is to crank up the heat to a specified value, and turn it down, but so far, I have not come up with an economical way or feasible way to make it easy on everyone.
Perhaps two pieces of inlaid floor tile (instead of glass) with 500 watt halogens under them just to get the temperature up quickly and then dim it to maintain the temperature.
This will probably get shot down too, but what if.... Submerse a temp sensor ?IN CONTACT? with the bottom of the "dish" and heat as it rocks. http://youtu.be/bD9_Ev3G08s
Worth a laugh, but this next one seems the easiest to me. http://youtu.be/SxT1Xjo-91M
That's how I make mine. I've got one of those bubble-etch tanks but never use it; it uses too much etchant, it takes ages to heat up, and it's too slow.
What heat source do you use? I though about a heat gun, quartz elements, even a clothes iron. I've seen many variations of the agitator, but the first post was probably the most simple design I've ever seen. Heating plastic to temp necessary might be bad and glass will be way heavier. There was a mention of using pens underneath the container, maybe small metal rollers? Think something like the hotdog warmers at convenience stores? Just much smaller and closer together?
I've mentioned it a couple of times. I put the etchant (FeCl3) in a small plastic container which is placed in an old washing up bowl with about 2" of just boiled water in it. The etchant container is rocked by hand. Etching takes well under 5 minutes.
Sorry, I've been a bit distracted while skimming the post. Sometimes the KISS method IS the best.
In my opinion, the is no simple method, with the exception of a hot plate and a temperature probe. The boiling water method might work well for the etchant, but the developer must be in the 100 to 110 degree fahrenheit range. I do not see how adding boing water to a dish is going to make the developer fit that range.
I really should not be posting on this since I have no real experience. I was just spit-balling ideas to heat stuff up. Hot plate and temperature probe sounds good, but developing and etching need agitation. This can be done manually, or something like the simple mechanical "dragging" agitator could do this as well. Not sure how well it would work on the hot plate though. The experiments I did with toaster ovens and reflow work taught me controlling the temp is one of the most difficult things. I actually ended up using a convection oven I bought at a thrift store, controlled by the BS2. It was very minimal on / off controlled through a relay. As far as I know the boards still work, even though I was skeptical at first.
I will allow you guys to decide if I'm spewing nonsense. Boiling water sounds simple if we can keep it in temp. This may be easier said than done. My thought is, if I'm etching a board I don't want to baby-sit it. The few boards I did etch *hand drawn RS boards* came out ok, but not something I was be proud of. The phone rang and well we know how that goes...
Some years ago the ARRL Handbook had a section on making PCBs at home. They recommended the use of that sort of lamp over the etchant container, with a small geared electric motor and an eccentric cam for rocking it. That arrangement could be used to keep developer at the requisite temperature. Adjusting the temperature is easy by moving the lamp towards and away from the container.
Instead of surrounding the tray with hot water, I am now thinking of building a heat chamber, where the tray would be surrounded by hot air. The air could be heated with a 500 watt halogen lamp.
I am not talking about ruining a perfectly good table. I am thinking more along the lines of a small table top custom made for making PCBs. For example, 2' X 4' piece of plywood with two small squares cut out by a jig saw. On the bottom of the table, install a boot for adapting 6" or 8" ducting, then istall a small section of duct, place the lamp inside the duct and fire it up.
Ahhh forget the duct and boots, just place the lamps under the trays. That way when the lamps go off there is no additional transfer of heat, except from the tray to the chemicals.
Better yet, I have a very cheap folding table that I bought from K-mart. The top is approximately a 1/4" thick and it is vinyl coated. It is the perfect table for the proposed solution, and heat lamps are cheap.
Take this table for example, only $29.99, cut out two squares for the trays, place heat lamps underneath, and I still have plenty of room on the top for my exposure box/cylinder. Now we are talking about a solution,
I was thinking about something like that, but I would end up with the same situation that I had with the coffee maker hot plate. The liquid temperature would continue to climb after shutting off the hot plate. I am sure it could work well if a person would develop some electronics and programming to back it up.
The toaster oven example I stated earlier was a perfect example of this. I had to turn the element off just before I hit temp and back on just before low temp limit. The trick was to write some software in javya *because this was what I was comfortable with on pc at the time* to calibrate the system by starting with a full temp limit. Then back off a bit until it was within tolerance. Not too hard to do. The hotplate SHOULD work, but the built in thermostat is worthless. Need a nice temp sensor. Found a fluke temp meter @ the pawn shop and hacked it in. Did I mention I was a dumb kid?? LOL
I just got back from the hardware store, where I purchased a 125 watt heat lamp and a lamp holder with a reflective shroud and spring clamp (total cost $10). I will now cut a square hole in a piece of 1/4" plywood for supporting a square tupperware bowl, place the bowl within the cutout, and fill it with a little bit of water. I will then place the heat lamp assembly under the bowl and heat it until the water reaches 104 degrees fahrenheit, at which point I will turn off the lamp and continue to watch the temperature.
If this experiment goes really well, I will then begin to lay out the holes in my cheap table and cut them out for a semi-final solution. I will then additionally make provisions for recessing half of my exposure box/cylinder into the table.
Talk about a nice setup. This will be a very slick setup, IF this next experiment goes well. I like the thought of it.
With the bulb approximately 3" from the bottom of the tray, it took 8 minutes to heat the water up from 95 degrees fahrenheit to 104 degrees fahrenheit. When I turned the bulb off, the temperature did not continue to go up. And it took approximately 3-1/2 minutes for the water temperature to drop below 100 degrees fahrenheit, which is definitely enough time to develop the board. However, with a couple of relays, thermocouplers, and a microcontroller, I am sure the temperature could be controlled to remain fairly stable, as would be necessary for the etching process.
At this point, I have come to the conclusion, that I will disassemble my flourescent UV exposure unit to remove the microcontroller, AC relay, and timer assembly, and apply them to something much better. Very soon, I will have a very nice exposing, developing, and etching table for making PCBs.
Bruce
EDIT: And I am certain, that I could reduce warm up time, by moving the bulb closer to the bottom of the tray.
Oh and I just came up with another fantastic idea. I will also make a couple of more holes in the table to allow for recessing a couple of small rinse buckets. Almost everything I need will be recessed into a small and cheap table.
I'm not familiar with your exposure hardware, but would it be possible to INCORPORATE it too? On table to rule all would be cool!
Please refer to Post #84 where I said:
I will then additionally make provisions for recessing half of my exposure box/cylinder into the table.
My exposure box/cylinder is a small unit for doing double-sided exposures, and the bottom half of the unit should easily recess into the table. For more information pertaining to my exposure unit, please refer to this thread:
Missed that little part. Once again, fingers moving quicker than my brain. I've been skimming through your recent posts and I'm quite excited. Especially now that it is one table. Way easier to justify to the wife. I'd still be working in the dirt though.:(
Additionally, I just thought of something else. I recently purchased a box of 100 nitrile rubber gloves from Walmart, and I will be making a holder under the table for this box of gloves, with an access opening on the table top to easily grab a glove when I need it.
As for the trash can, I think I will leave that on the floor
Comments
water vibrates when exposed to MW thats what mostly heats the food.
and used right MW can even chill. but, unless you are prepared for the microwave to go skyhigh please don't try it.
I have seen a few people get a trip to the ER over trying to use MW in other ways.
one of them put an object with a metal rod in and the rod focused the MWs out and he actually cooked his own chest! serious where the rod pointed at was killed about 2 inches deep.
marble may explode, refocus the MWs or if the crystal structures on the stone is right it could act like a ceramic capacitor inducting the MWs into a stored voltage and when you get close ZAP like a bug.
just plz believe me on this, MWs = danger be careful.
http://en.wikipedia.org/wiki/Microwave_oven
Glass and stone can even melt!
I forgot all about that.
One thing that I am learning the hard way is that if you apply a specified temperature to a target and you want that target to be the same temperature, the heating process is very slow.
I think the ideal process is to crank up the heat to a specified value, and turn it down, but so far, I have not come up with an economical way or feasible way to make it easy on everyone.
Perhaps two pieces of inlaid floor tile (instead of glass) with 500 watt halogens under them just to get the temperature up quickly and then dim it to maintain the temperature.
http://youtu.be/bD9_Ev3G08s
Worth a laugh, but this next one seems the easiest to me.
http://youtu.be/SxT1Xjo-91M
In my opinion, the is no simple method, with the exception of a hot plate and a temperature probe. The boiling water method might work well for the etchant, but the developer must be in the 100 to 110 degree fahrenheit range. I do not see how adding boing water to a dish is going to make the developer fit that range.
Bruce
I will allow you guys to decide if I'm spewing nonsense. Boiling water sounds simple if we can keep it in temp. This may be easier said than done. My thought is, if I'm etching a board I don't want to baby-sit it. The few boards I did etch *hand drawn RS boards* came out ok, but not something I was be proud of. The phone rang and well we know how that goes...
It has a thermostat, a fairly large surface and costs ca 35 bucks. And no lamps to replace.
Although I would dedicate it to heating the tray with etchant.
I was thinking about something like that, but I would end up with the same situation that I had with the coffee maker hot plate. The liquid temperature would continue to climb after shutting off the hot plate. I am sure it could work well if a person would develop some electronics and programming to back it up.
Bruce
I just got back from the hardware store, where I purchased a 125 watt heat lamp and a lamp holder with a reflective shroud and spring clamp (total cost $10). I will now cut a square hole in a piece of 1/4" plywood for supporting a square tupperware bowl, place the bowl within the cutout, and fill it with a little bit of water. I will then place the heat lamp assembly under the bowl and heat it until the water reaches 104 degrees fahrenheit, at which point I will turn off the lamp and continue to watch the temperature.
If this experiment goes really well, I will then begin to lay out the holes in my cheap table and cut them out for a semi-final solution. I will then additionally make provisions for recessing half of my exposure box/cylinder into the table.
Talk about a nice setup. This will be a very slick setup, IF this next experiment goes well. I like the thought of it.
Bruce
With the bulb approximately 3" from the bottom of the tray, it took 8 minutes to heat the water up from 95 degrees fahrenheit to 104 degrees fahrenheit. When I turned the bulb off, the temperature did not continue to go up. And it took approximately 3-1/2 minutes for the water temperature to drop below 100 degrees fahrenheit, which is definitely enough time to develop the board. However, with a couple of relays, thermocouplers, and a microcontroller, I am sure the temperature could be controlled to remain fairly stable, as would be necessary for the etching process.
At this point, I have come to the conclusion, that I will disassemble my flourescent UV exposure unit to remove the microcontroller, AC relay, and timer assembly, and apply them to something much better. Very soon, I will have a very nice exposing, developing, and etching table for making PCBs.
Bruce
EDIT: And I am certain, that I could reduce warm up time, by moving the bulb closer to the bottom of the tray.
Please refer to Post #84 where I said:
My exposure box/cylinder is a small unit for doing double-sided exposures, and the bottom half of the unit should easily recess into the table. For more information pertaining to my exposure unit, please refer to this thread:
Bruce
As for the trash can, I think I will leave that on the floor
Bruce