Alas my friend, you are half right also...
You are talking about the old method of photo plotting. They now use lasers to expose film. Perhaps you should also read the "DVD Laser Diode And Optical Block (Future Laser Photoplotter)" thread to gain a little more insight
Err ? - I believe I already said that. It is now more widely called Dry Film imaging.
XY tables and classic photo-plotters for Gerber files, you will not find in commercial operation, which I thought was the line of your original question ?
Well it took quite some time to get motivated. However throughout the day, I did a little here and there to get everything ready for some serious testing. As a final step, I checked the fit of everything. When I attempted to fit the smaller photo mask to the exposure plate, the two layers of the photo mask seperated, because it was a fairly snug fit and it broke the glue seam apart. It definitely was not as durable as I initially thought. From this point, I will either crazy glue the seams together or fuse them together electronically somehow. Additionally, I am reevaluating a couple other minor problems, for potential solutions.
Refering to my last post, concerning the durability of the photo mask and the other minor problems that I was having, here is what I decided to do and what not to do.
Initially I considered trimming the photo masks with resistance wire, which would have permanently bonded the two layers of the photo mask together, but I came to the conclusion that most people would not bother with this method, and I am seeking a good solution for everyone. However, many of you who may be reading this, probably have a much different exposure system than me. Considering that I am also attempting a commercial venture, much of my solution will also coincide with my exposure box/cylinder system. If interested, you can find more information about that system here:
For the most part, I was very happy with the double layered mask, with the exception of it coming apart at the seems. These masks had very nice registration alignment, and they were very close to being completely opaque. However, due to the tight tolerances of my exposure box system, the Elmers glue just did not hold up. To overcome this problem, I have decided upon two things:
I will be modifying the design of my exposure plate to readily adapt to a modified two layer mask, which is as follows.
Instead of making the masks to the exact size of the desired PCB, all masks will now be constructed to a size of 4" X 5". Along the outer perimeter of each mask, I will provide a series of registration marks, which will be spaced approximately 1/4" apart from each other.
So how does this help to solve the durability problem of a double layered mask? Read on to hear my proposed solution.
When I print my masks, I will also print the outer perimeter of the mask, which will allow each mask to easily be trimmed to the appropriate size. After trimming the masks to the appropriate size, I will then align the duplicate layers for each mask according to the forementioned registration marks. Once the duplicate masks have been properly aligned, I will then pierce each registration with a hot sewing needle or sharpened piece of metal rod, which should sufficiently bond the duplicate masks together. In reality, I will probably sharpen a piece of 1/8" metal rod and use this as compared to a sewing needle, just to obtain a better grip. Bonding the two layers together, probably shouldn't take more than a couple minutes. After bonding the two layers together, I will lightly sand the bonding locations with some very fine sand paper just to remove any raised edges.
Although I have not created any masks with this method yet, I have taken the time to pierce two sheets of transparent film with a red hot needle and the results look promising.
That would probably be a perfect solution for most people, depending on their exposure setup.
In my current exposure setup, it would not work, because the boards and masks are cut to actual size before exposure. However, as I stated, I am going to make an alternate design, in which all masks will be 4 X 5. In this type of setup, it might work, but in the past, I have had problems with adhesives oozing because the exposure plate is close to exposure bulb.
Thanks for the suggestion, I am sure someone will find it useful.
After quite a bit of deliberation and a little bit of experimentation, I believe I have come up with the very best solution for a low cost, fairly high quality, and durable photomask. Of course it won't compare to a purchased laser photo plot, but how many DIYers is going to order one of those?
Referring to an earlier post, due to my special circumstances concerning my exposure plate design, I was contemplating altering my exposure plate to make double layered transparency photo masks more adaptable, but I wanted to try one more experiment before making any alterations, which resulted in a solution for me.
Creating an opaque photo mask by doubling up laser printed transparencies is nothing new, and there are plenty of examples on the internet. However, in my case, due to the design of my exposure plate, the mask must be the exact same size as the final board. This requirement previously caused me problems due to seperation of the two transparency layers, because the glue did not hold, and tape was definitely out of the question, because it would extend into the exposure area.
So here is my solution for low cost, fairly high quality, and durable photomasks.
Tools, Materials, And Equipment Required:
A good work area with adequate lighting
Magnifying glass
Scratch awl
Minimum of a 600 DPI laser printer
Utility knife
Thin metal ruler
Clean sheet of glass for mask alignment, or a light table
Clean sheet of metal plate (size is dependant upon the size of the mask
Premium laser transparency film
Propane or MAPP gas with torch tip
Bastard file
Acrylic Krylon Crystal Clear Satin spray paint
Clean piece of cardboard
Directions:
[LIST=1|INDENT=1]
[*]When designing the mask, include an outline of the board.
[*]Provide several registration marks around the perimeter of the board outline, with the center of the registration marks being approximately 1/2 an inch from the edge of the board.
[*]Print two copies of each mask at the highest possible density and DPI settings.
[*]Place the masks onto the cardboard and spray the masks with a fine even coat of the Crystal Clear Satin. This will blend and darken the toner from the printer. Give them sufficient time to dry.
[*]Place two of the duplicate masks onto the glass, with one side of regristration marks barely overhanging the edge of the glass, and align the registration marks using the magnifying glass.
[*]Light up the torch and heat the tip of the awl to red hot, and then pierce both layers of transpancies through the registration marks that are overhanging the glass. Repeat this procedure until all registration marks have been pierced. Do not go to deep when piercing, just enough to bond the two sheets.
[*]Align the metal ruler at a predetermined trim location. Heat the tip of the utility knife with the torch until it is red hot. While firmly holding down the metal ruler, run the hot utiility blade of along the edge of the ruler. The goal is to remove the excess mask material through a melting process, not a cutting process. It may take a couple of passes to completely remove the excess with a red hot tip. Continue this process until all excess material has been removed. At this point, both layers should be bonded together.
[*]Turn off the torch and put it in a safe location to cool down.
[*]Move the bonded masks to the metal plate and align one of the trimmed edges of the mask with the edge of the metal plate. Now take the file and gently remove any high points from the mask that resulted from trimming with the hot utility knife. Repeat this process until all burrs have been removed from the mask.
[*]Remove any dust or debris that may have accumulated on the mask. I would imagine that with enough Crystal Clear Satin coating, it might even be safe to wash them.
[/LIST]Well there you have it folks
Or, just use a suitable inkjet printer and save yourself a lot of trouble.
As we all know, Leon is a firm believer in inkjet printers And I must admit that his inkjet does put out a nice mask, however I do not have a 1200 DPI inkjet printer, and after looking at the result printouts of both his printer and mine, I still prefer the laser printer due to it's line definition. However once again, his inkjet does have better line seperation for fine lines.
In my opinion, as established by comparisons, there are pros and cons to both types of printers, which are as follows:
Ink Jet
Pros:
For lines smaller than 10 mil there is much better line seperation
Printouts from an inkjet appear to be more opaque than a laser printout
Cons:
Poor line definition
Laser
Pros:
Good line definition
Cons:
For lines smaller than 10 mil there is poor line seperation
Printouts from a laser are more translucent than an inkjet printout.
If you need trace widths smaller than 10 mil, I highly suggest using an inkjet printer, but if you prefer better line definition on traces larger that 10 mil, I would go with a laser printer.
Whatever printer you may decide to use, you want the positive/negative image (photo mask) to be as opaque as possible. Even though Leon may not admit it, doubling up inkjet tranparency printouts may also produce better results for your PCBs.
In my opinion, the most difficult part of making your own PCBs is the exposure process. The exposure time of the PCB will be directly related to the quality and opacity of the photo mask. An opaque mask can be exposed for a longer period of time as compared to one that is slightly translucent, which will result in a much better breakdown of the photo resist film in the transparent areas of the mask, and the opaque areas of the mask will still have good photo resist, which will result in easier developing and etching.
Use you own judgement, but I can tell you that my biggest problem has always been the opacity of the photo mask and fine line seperation.
As a side note, referring to Post #39, it is a little bit of a pain working with the torch to trim the masks, so I have decided to try two more experiments:
I am going to attempt to trim the masks with a soldering iron.
If the soldering iron fails to do the job, I will create a little handheld pen with a small piece of nichrome wire (resistance wire) installed at the tip which can be plugged into a wall wart
Referring to my previous post, I have decided to design, expose, and etch a simple two trace circuit board which will contain provisions for a wall wart plug and a 2 position screw clamp. The wall wart will plug into the wall wart plug, and the resistance wire will be attached to the 2 position screw clamp. This should enable me to bond and trim the masks quickly and easily.
Hopefully I will have a wall wart without too much current. I am hoping I can achieve this without the need for more resistance in the circuitry.
When I get it all figured out, I will be able to produce some very nice DOUBLE-SIDED PCBs very quickly.
Experimentation is a good thing. There is an old saying.... "If you continue to do what you have always done, you will continue to get what you have always gotten."
I have made double-sided boards, it wasn't difficult. I stuck the top and bottom transparencies together with masking tape ensuring that they were properly aligned, inserted the double-sided board, and exposed the two sides in turn.
I haven't found many people who can equal them, let alone get better results.
I've supplied home-made boards when designing systems for people, to save time, intending to replace them with professionally-made boards later. In some cases, they are still using my boards, many years later.
I further challenge you to make the PCB for this board http://www.st.com/internet/evalboard/product/152186.jsp for which all the gerbers can be found at that link under the tab design support. To make it even more difficult, add four mounting holes to the board. At which point, we can both upload photos and let the forum members judge our endeavors and declare the winner.
Bruce
EDIT: No drilling required, just the etched board, considering I don't have my driller built just yet
I thought it would only be fair to mention that this is a quality challenge and not a race, so please take your time. I currently have more pressing issues than this challenge, however, I would imagine that I should have a PCB and photos within a weeks time.
Here is my recipe for my second attempt at making a film cutter/fuser. This one appears to work pretty well.
CAUTION: Please do not attempt this project if you are unfamiliar with higher voltages and safe wiring practices.
CAUTION: Please be aware that this device has the abiltity to burn plastic. If you decide to make this device, you must avoid burning plastic with this device. Burning plastics contain a high level of toxins, one of which is cyanide.
CAUTION: Please be aware that this device uses a red hot wire to melt plastic and may cause serious burns if accidently applied to your skin. While the tool is energized and the cutting blade is red hot, please take the appropriate precautions to prevent accidental burns.
FILM CUTTER/FUSER
Purpose:
The purpose of this project is to create a tool to join two identical layers of laser printed transparencies in order to create a more opaque photo mask that can be used to make your own printed circuit boards.
Difficulty Level And Time Required
Providing that a person is familiar with residential electrical devices, this project is very easy to complete and should take no longer than an hour to complete once all the material and equipment have been gathered.
Tools, Materials, And Equipment Required:
0.047" 0.032" music wire
12-Position European-Style Mini Terminal Strip (Radio Shack #274-680)
Electrical tape
12 Gauge zip cord
Small flat blade screw driver
Drill press
Sanding drum
Needle nose pliers
Dimmer switch
Receptacle outlet
4 X 4 electrical box
Ground screw
Two gang raised electrical cover to match the dimmer and receptacle outlet
14/3 SO cord or similar
Some type of electrical fitting to adapt the cord to the electrical box
Male plug end
Battery charger 2 amps @ 12 volts
Some means to temporarily attach zip cord ends to the aligator clamps of charger
Heavy duty diagonal cutters
Wire strippers
Directions:
Do not attempt this if you are unfamiliar with working on higher voltages and safe wiring practices.
Wire up the dimmer to the receptacle using these materials: 14/3 cord, electrical fitting, electrical box, raised cover, ground screw, raised cover, male plug end, dimmer, and receptacle.
Using needle nose pliers, bend a piece of music wire into a U-shape, with the center of the legs being equal to the center distance between two terminals on the terminal strip. Then cut the legs to a length of 5/8". EDIT: The previously mentioned U-shape is comprised of two ninety degree angles, instead of two legs with a semi-cirlce.
Sharpen the bottom of the U-shaped piece with a sanding drum and drill press. Sharpen the cutting blade. Through experimentation, I have determined that the film cutter/fuser works best when the leading ninety degree angle has been ground thin for approximately 3/16 of an inch in both directions, and with the bottom corner edge beveled on both sides, similar to a razor blade or utility blade. Additionally, this entire ninety degree angle should have a pointed corner. Make it thin and it cuts like butter, but apply current very, very slowly, when you get to that point.
Install the U-shaped wire into the last two positions of the terminal strip and tighten the terminal screws.
On the opposite side of the terminal, apply a conductor from the zip cord to each leg of the U-shape piece, and tighten the terminal screws. The forementioned terminal strip is only rated for 16 gauge, but the 12 gauge wire will fit.
Fold the zip cord back along the terminal strip and secure with electrical tape.
By whatever means available, attach the other end of the zip cord to the aligator clips of the battery charger.
Place the dimmer switch into the off position.
Plug the charger into the receptacle outlet.
Plug the previously made electrical assembly in an availabe outlet.
Slowly turn the dimmer on. If you apply to much current, the U-shaped piece will burn in two or it will be too hot to properly cut and fuse the plastic film. Only use in a well ventilated area and avoid breathing any fumes if the film melts too quickly.
IMPORTANT NOTE: It works much better making several passes with a lower temperature at the cutting blade, then making one pass with the blade at a higher temperature.
Who needs glue or tape
Bruce
EDIT: If you decide to make one of these, please take the time to make some spare blades. While I was happily cutting along, the sound of the charger changed from a rough hum to a mild hum and the red tip had turned black. At first I thought I overheated the charger, so I let it sit for a few minutes and tried again, but still no juice. Still hoping it was overheated, I let it set for an hour and tried again, but once again, still no juice. I thought I had burned up my charger and started to dispair And just when I was about to pay my last respects, I noticed a crack in the blade. Keep this in mind if you lose power. Check for cracks before deep sixing your power supply, because the crack was very hard to see. All is good
I just made my first double layered positive with a tool as described above and I must say it turned out pretty nice. However, I think the blade needs just a little tweaking because of plastic build up. But I suppose the blade could also be too hot or too cold. I need to experiment just a little more to get the feel for it.
I now have the film cutter/fuser down to a science. Successful operation of the film cutter/fuser is all dependant upon how the blade is sharpened and how much current is applied. I am now able to cut and fuse two layers of transparencies together with very little melted plastic buildup. Please refer to Post #58 and item #4 in the Directions section for an update to properly sharpen the cutting blade.
Comments
Err ? - I believe I already said that. It is now more widely called Dry Film imaging.
XY tables and classic photo-plotters for Gerber files, you will not find in commercial operation, which I thought was the line of your original question ?
Well it took quite some time to get motivated. However throughout the day, I did a little here and there to get everything ready for some serious testing. As a final step, I checked the fit of everything. When I attempted to fit the smaller photo mask to the exposure plate, the two layers of the photo mask seperated, because it was a fairly snug fit and it broke the glue seam apart. It definitely was not as durable as I initially thought. From this point, I will either crazy glue the seams together or fuse them together electronically somehow. Additionally, I am reevaluating a couple other minor problems, for potential solutions.
I will keep you posted on the photo masks.
Bruce
Refering to my last post, concerning the durability of the photo mask and the other minor problems that I was having, here is what I decided to do and what not to do.
Initially I considered trimming the photo masks with resistance wire, which would have permanently bonded the two layers of the photo mask together, but I came to the conclusion that most people would not bother with this method, and I am seeking a good solution for everyone. However, many of you who may be reading this, probably have a much different exposure system than me. Considering that I am also attempting a commercial venture, much of my solution will also coincide with my exposure box/cylinder system. If interested, you can find more information about that system here:
- I will be modifying the design of my exposure plate to readily adapt to a modified two layer mask, which is as follows.
- Instead of making the masks to the exact size of the desired PCB, all masks will now be constructed to a size of 4" X 5". Along the outer perimeter of each mask, I will provide a series of registration marks, which will be spaced approximately 1/4" apart from each other.
So how does this help to solve the durability problem of a double layered mask? Read on to hear my proposed solution.When I print my masks, I will also print the outer perimeter of the mask, which will allow each mask to easily be trimmed to the appropriate size. After trimming the masks to the appropriate size, I will then align the duplicate layers for each mask according to the forementioned registration marks. Once the duplicate masks have been properly aligned, I will then pierce each registration with a hot sewing needle or sharpened piece of metal rod, which should sufficiently bond the duplicate masks together. In reality, I will probably sharpen a piece of 1/8" metal rod and use this as compared to a sewing needle, just to obtain a better grip. Bonding the two layers together, probably shouldn't take more than a couple minutes. After bonding the two layers together, I will lightly sand the bonding locations with some very fine sand paper just to remove any raised edges.
Although I have not created any masks with this method yet, I have taken the time to pierce two sheets of transparent film with a red hot needle and the results look promising.
Bruce
Ideally they would be outside the PCB clamp area, so even their thickness does not affect the film-pcb clamping.
I think there are also glue-only dots, but they tend to have more wastage, and can pollute things
That would probably be a perfect solution for most people, depending on their exposure setup.
In my current exposure setup, it would not work, because the boards and masks are cut to actual size before exposure. However, as I stated, I am going to make an alternate design, in which all masks will be 4 X 5. In this type of setup, it might work, but in the past, I have had problems with adhesives oozing because the exposure plate is close to exposure bulb.
Thanks for the suggestion, I am sure someone will find it useful.
Bruce
After quite a bit of deliberation and a little bit of experimentation, I believe I have come up with the very best solution for a low cost, fairly high quality, and durable photomask. Of course it won't compare to a purchased laser photo plot, but how many DIYers is going to order one of those?
Referring to an earlier post, due to my special circumstances concerning my exposure plate design, I was contemplating altering my exposure plate to make double layered transparency photo masks more adaptable, but I wanted to try one more experiment before making any alterations, which resulted in a solution for me.
Creating an opaque photo mask by doubling up laser printed transparencies is nothing new, and there are plenty of examples on the internet. However, in my case, due to the design of my exposure plate, the mask must be the exact same size as the final board. This requirement previously caused me problems due to seperation of the two transparency layers, because the glue did not hold, and tape was definitely out of the question, because it would extend into the exposure area.
So here is my solution for low cost, fairly high quality, and durable photomasks.
[*]When designing the mask, include an outline of the board.
[*]Provide several registration marks around the perimeter of the board outline, with the center of the registration marks being approximately 1/2 an inch from the edge of the board.
[*]Print two copies of each mask at the highest possible density and DPI settings.
[*]Place the masks onto the cardboard and spray the masks with a fine even coat of the Crystal Clear Satin. This will blend and darken the toner from the printer. Give them sufficient time to dry.
[*]Place two of the duplicate masks onto the glass, with one side of regristration marks barely overhanging the edge of the glass, and align the registration marks using the magnifying glass.
[*]Light up the torch and heat the tip of the awl to red hot, and then pierce both layers of transpancies through the registration marks that are overhanging the glass. Repeat this procedure until all registration marks have been pierced. Do not go to deep when piercing, just enough to bond the two sheets.
[*]Align the metal ruler at a predetermined trim location. Heat the tip of the utility knife with the torch until it is red hot. While firmly holding down the metal ruler, run the hot utiility blade of along the edge of the ruler. The goal is to remove the excess mask material through a melting process, not a cutting process. It may take a couple of passes to completely remove the excess with a red hot tip. Continue this process until all excess material has been removed. At this point, both layers should be bonded together.
[*]Turn off the torch and put it in a safe location to cool down.
[*]Move the bonded masks to the metal plate and align one of the trimmed edges of the mask with the edge of the metal plate. Now take the file and gently remove any high points from the mask that resulted from trimming with the hot utility knife. Repeat this process until all burrs have been removed from the mask.
[*]Remove any dust or debris that may have accumulated on the mask. I would imagine that with enough Crystal Clear Satin coating, it might even be safe to wash them.
[/LIST]Well there you have it folks
Bruce
As we all know, Leon is a firm believer in inkjet printers
In my opinion, as established by comparisons, there are pros and cons to both types of printers, which are as follows:
- For lines smaller than 10 mil there is poor line seperation
- Printouts from a laser are more translucent than an inkjet printout.
If you need trace widths smaller than 10 mil, I highly suggest using an inkjet printer, but if you prefer better line definition on traces larger that 10 mil, I would go with a laser printer.Whatever printer you may decide to use, you want the positive/negative image (photo mask) to be as opaque as possible. Even though Leon may not admit it, doubling up inkjet tranparency printouts may also produce better results for your PCBs.
In my opinion, the most difficult part of making your own PCBs is the exposure process. The exposure time of the PCB will be directly related to the quality and opacity of the photo mask. An opaque mask can be exposed for a longer period of time as compared to one that is slightly translucent, which will result in a much better breakdown of the photo resist film in the transparent areas of the mask, and the opaque areas of the mask will still have good photo resist, which will result in easier developing and etching.
Use you own judgement, but I can tell you that my biggest problem has always been the opacity of the photo mask and fine line seperation.
Bruce
My line definition (on the actual PCB) with an inkjet is just as good as that delivered by a laser printer.
Hopefully I will have a wall wart without too much current. I am hoping I can achieve this without the need for more resistance in the circuitry.
All I got to say is this....
When I get it all figured out, I will be able to produce some very nice DOUBLE-SIDED PCBs very quickly.
Experimentation is a good thing. There is an old saying.... "If you continue to do what you have always done, you will continue to get what you have always gotten."
Bruce
I've supplied home-made boards when designing systems for people, to save time, intending to replace them with professionally-made boards later. In some cases, they are still using my boards, many years later.
I may have lost the pattern challenge, but you never accepted my challenge, referring to Post #152 at http://forums.parallax.com/showthread.php?135950-ATTN-PCBers-SUBJECT-New-website-and-exposure-box-design-for-your-creative-needs&p=1073035&viewfull=1#post1073035
If you need Gerbers instead of a board file, I can supply it.
Bruce
And if you decide to accept the challenge, please include the quarter in your photos
If you are really ambitous....
I further challenge you to make the PCB for this board http://www.st.com/internet/evalboard/product/152186.jsp for which all the gerbers can be found at that link under the tab design support. To make it even more difficult, add four mounting holes to the board. At which point, we can both upload photos and let the forum members judge our endeavors and declare the winner.
Bruce
EDIT: No drilling required, just the etched board, considering I don't have my driller built just yet
I'll have a go at it!
I thought it would only be fair to mention that this is a quality challenge and not a race, so please take your time. I currently have more pressing issues than this challenge, however, I would imagine that I should have a PCB and photos within a weeks time.
Bruce
Was I correct about the top and bottom layers? I imported the Gerbers into Pulsonix.
Something digital with 8/8 mil tracks would be more meaningful.
Here is my recipe for my second attempt at making a film cutter/fuser. This one appears to work pretty well.
CAUTION: Please do not attempt this project if you are unfamiliar with higher voltages and safe wiring practices.
CAUTION: Please be aware that this device has the abiltity to burn plastic. If you decide to make this device, you must avoid burning plastic with this device. Burning plastics contain a high level of toxins, one of which is cyanide.
CAUTION: Please be aware that this device uses a red hot wire to melt plastic and may cause serious burns if accidently applied to your skin. While the tool is energized and the cutting blade is red hot, please take the appropriate precautions to prevent accidental burns.
FILM CUTTER/FUSER
- Do not attempt this if you are unfamiliar with working on higher voltages and safe wiring practices.
- Wire up the dimmer to the receptacle using these materials: 14/3 cord, electrical fitting, electrical box, raised cover, ground screw, raised cover, male plug end, dimmer, and receptacle.
- Using needle nose pliers, bend a piece of music wire into a U-shape, with the center of the legs being equal to the center distance between two terminals on the terminal strip. Then cut the legs to a length of 5/8". EDIT: The previously mentioned U-shape is comprised of two ninety degree angles, instead of two legs with a semi-cirlce.
- Sharpen the bottom of the U-shaped piece with a sanding drum and drill press. Sharpen the cutting blade. Through experimentation, I have determined that the film cutter/fuser works best when the leading ninety degree angle has been ground thin for approximately 3/16 of an inch in both directions, and with the bottom corner edge beveled on both sides, similar to a razor blade or utility blade. Additionally, this entire ninety degree angle should have a pointed corner. Make it thin and it cuts like butter, but apply current very, very slowly, when you get to that point.
- Install the U-shaped wire into the last two positions of the terminal strip and tighten the terminal screws.
- On the opposite side of the terminal, apply a conductor from the zip cord to each leg of the U-shape piece, and tighten the terminal screws. The forementioned terminal strip is only rated for 16 gauge, but the 12 gauge wire will fit.
- Fold the zip cord back along the terminal strip and secure with electrical tape.
- By whatever means available, attach the other end of the zip cord to the aligator clips of the battery charger.
- Place the dimmer switch into the off position.
- Plug the charger into the receptacle outlet.
- Plug the previously made electrical assembly in an availabe outlet.
- Slowly turn the dimmer on. If you apply to much current, the U-shaped piece will burn in two or it will be too hot to properly cut and fuse the plastic film. Only use in a well ventilated area and avoid breathing any fumes if the film melts too quickly.
IMPORTANT NOTE: It works much better making several passes with a lower temperature at the cutting blade, then making one pass with the blade at a higher temperature.Who needs glue or tape
Bruce
EDIT: If you decide to make one of these, please take the time to make some spare blades. While I was happily cutting along, the sound of the charger changed from a rough hum to a mild hum and the red tip had turned black. At first I thought I overheated the charger, so I let it sit for a few minutes and tried again, but still no juice. Still hoping it was overheated, I let it set for an hour and tried again, but once again, still no juice. I thought I had burned up my charger and started to dispair
Bruce
I now have the film cutter/fuser down to a science. Successful operation of the film cutter/fuser is all dependant upon how the blade is sharpened and how much current is applied. I am now able to cut and fuse two layers of transparencies together with very little melted plastic buildup. Please refer to Post #58 and item #4 in the Directions section for an update to properly sharpen the cutting blade.
Bruce
Got pictures?
Jim