Prototype build of LED ornament with dry film photoresist.
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- Опубликовано: 31 май 2017
- I designed this PCB to use for tests with using the dry film photoresist that is widely sold on eBay. I've never had much luck with it in the past, but was trying it with a technique where it is applied onto a film of moisture to help it slide and allow full removal of bubbles and ripples. I'll be doing some more tests with it, especially as it provided very good results with wide margins of exposure, developing and etching.
I also tried sodium persulfate as an etchant, but was not impressed. It's nice that it's clear, but it is slow and has a short shelf life as opposed to the traditional ferric chloride etchant which has near enough unlimited shelf life.
The design itself started off as a cluster of LEDs with two rows of resistors, but then I decided to put the resistors in a circle round the LED connections, and then added the channel name in an arc round the board too. 
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This is why I like bigclive. You start out by testing an etching photoresist, and then end up building a color-changing tree. And diagnosing a faulty lead. 10/10
Clive, you do understand and know that we love you and your videos. As simple as that.
I imagine bigclive giving directions to his friends to get to visit his house:
"Yeah, once you dock at the Island of Man, you'll see an eye blistering glowing orb from the distance, just get that light"
*Your problem with the Sodium persulfate is heat.* It doesn't do much at room temperature, but at 30°C you get an immediate reaction and at 40°C it is very quick. There's an upper limit where it starts to degrade on its own. I don't exactly know what it was but somewhere around 50°C. I usually heat the solution to a point where I can still put my fingers in without hurting (so I guess that's between 40 and 50°C). A halogen flood light works well for that ;) . Put it in a transparent container on top of that and you have the additional benefit of light shining through the board so you can easily tell if the small holes in the pads have been etched.
There's also no problem keeping the etchant around for month or even years if stored cool. Just don't store it in a completely gas tight container, because there's always a little bit of oxygen coming out of the solution. Having a used solution with a little bit of copper in it actually accelerates the etching process.
Over all it's much cleaner than ferric chloride and the results are sharper in my opinion (that also depends on the way of exposure of course).
exactly!
Yep, at work I use 70°C water out of the "Billi" water boiler (used for making tea & coffee).
Super result - The proportions look very tree-like, one of your best designs; probably my favourite to date. Well done.
Every time I look at it, I think it really does have the shape of a small tree.
every time i look your videos i think that there's something really wrong in England
Persona Gentile ... It sounds like someone needs a diaper change!
why? what's the purpose of that shit? what's that ugly thing? i mean really, this man needs help. What's the pupose of watching someone drawing schematics of the worstest shit from china?
What's worse? Us for watching something that we enjoy or you purposely coming onto a video of something you don't enjoy and berating strangers?
Get back to Minecraft and fidget spinners you sad little boy.
10:27 - for a second i thought that the clip on the bag broke - that would have been a mess.
It has started oozing very slightly at pinholes on the seam. I've just made a new bag up with a fresh length of heavy duty layflat tubing and some suitable bag seals.
Discussing the making of happy little LED trees in a soothing voice... Clive is the Bob Ross of electronics.
There are my favorite BigClive videos. PCB making stuff.
I like these little project videos you do every now & then, they're very 'Bob Ross'-esque.
Very good. Takes me back to when my dad used this technique on silk screens for his screen printing. Once the screen has the hardened gel on it, he could knock off hundreds of t-shirts or machine gauges. That all disappeared over the years with cheaper automation, but it was a skill to be admired.
That technique is still very common.
ok . im really having fun watching this process, clive your so cool with all these homade circut board videos! its like i havent even dented your library of old videos. Thank you so much for all of these.
Great result, nice to see you doing another little LED project. A very nice, easy and very pleasing design.
I love your enthusiasm for this stuff.
That bit about storing Ferric Chloride for 10 years and it still working is no joke. I have a bottle I purchased from radio shack in 2002 that's still about half full I use occasionally. It still works as good as the day I bought it. Now, you may ask why I still have a partial bottle of etchant from that long ago. The way i etch my boards, it takes very little etchant to do the job. I heat it up in the microwave until its luke warm, then soak a sponge. Then in a plastic container, wipe the board with it. When the sponge looses the etchant, soak it back up from the container and repeat until it's etched. Usually only takes 3-5 minutes to etch a 5x8 cm double-sided board. When done squeze the etchant out of the sponge into a "used etchant" container and reuse until it's expired. This method really saves a lot of etchant and makes a bottle last forever! Hope that's useful for someone.
That was just an excellent video. Really liked the PCB part with good clear explanations
This was very entertaining to watch. I work in the industrial field and remember learning how to do this in the late 80s/early 90s. Back then an industrial circuit board would cost sometimes $10k. So i had to learn how to trouble shoot and repair boards at the component level. I feel that this is now a lost art due to boards being pumped out from just about everywhere and also PLCs replaced a lot of dedicated circuit boards. So I had to learn to write PLC logic. I really enjoy your videos. Thanks.
I just cannot get over the etch-resist's color. That glorious blue-ish purple!
And then with the copper!
That just does a lot for me.
>>Look at this guy, fixating on colors. ;P
Your Videos are so therapeutic :)
Nice one, Clive. Looks good in colour.
Very nice project, good looking!
Your are the Bob Ross of electronics IMO, it looks awesome!
Fun to watch this project all the way through. The orange/black wire combination would be perfect around Halloween.
What a great project, will have to give it a go myself!
I do love your ornamental lights :)
I've been using Sodium Persulfate for years, it works very well if used properly. The key thing you were missing here is heat. They way I do is to use two old icecream containers or similar. Boil some water and pour a good amount into the first container, sit the other one inside and put about a tablespoon of the crystals in (depends on board size but for the board you made it would've been enough). Now add just enough water to cover the PCB and add a wee bit extra. Plop the board in and keep swirling the etchant around. The first few seconds it might look like nothing it happening but then it rapidly starts getting to work and in 2-5 minutes it's done.
The reason I use two containers like that is so I can use a small amount of etchant and still keep it at temperature so it works quickly. The small amount I use I then discard. You use so little of it and it's so cheap that it's silly to keep the solution around IMHO.
second. no-one called it.
interesting. have been toying with the idea of moving my solderless breadboard creations to circuit boards. this video will come in handy when the time comes :)
Fantastic! And Clive makes it look so easy!! :-)
You are the Bob Ross of circuitry!
Very cool. I've used that way of powering a project before (cheap eBay USB cable and slots in the PCB for a cable tie) - it's a fantastic way of powering things, especially for designing kits for school students. They're obviously unlikely to have a bench-top power supply or even a 12V wall-wart with the right connector, but pretty much guaranteed to have a USB charger or power bank!
excellent very enjoyable to watch as always
Thanks Clive
That was really cool, thanks for sharing.
Clive, back in the 70's when I first started toying with photo etching. I came across a spray on light sensitive material. It worked quite well as long as the copper was clean. I was able to paint a batch of boards and keep them for a couple of years with great results each time. Sorry that I have not kept track as to weather or not it is still available. Much easier than squeegees and laminating machines, I imagine.
Thanks, Clive. Careful use of a centre punch helps greatly if the holes are not etched out enough.
How handy, completely forgot you had made this video. I've bought some of that dry film, mine came on a cardboard roll so no creases (I hope, not tried it yet). Worked out that the film and standard boards works out nearly half the price of the ones with the film already on.
Just need to finish building the LED exposure box and have a go at my first PCB.
Wow ! Color changing LED's ??? Never seen before something like that. Cool and try friendly too ...
Sodium persulfate works well and fast, you just need to keep the solution at about 50°C the whole etching time...
This.
Sodium Percarbonate (Oxyclean products) works quite fast and well too.
BILLY MAYS HERE WITH ANOTHER FANTASTIC PRODUCT!
Agree, heating it works a treat and will etch fast
Yes it needs heat, bubbles also good, regarding aging I have used 2 year old solution with out trouble, great blessing is it doesn't stain like Ferric Chloride. Enjoyed the video!
Nice results, I'll have to give the dry film a go, photosensitive boards cost a fortune! Many thanks for the content sir!
I would love to buy this at the stage pre-drilling, looks so cool as a decorative item just even at that stage let alone e the amazing finished product! I just would love that flat, etched pattern to make into a Big Clive themed fridge magnet
Work of art mate.
I think your finger dexterity is, by far, the most impressive parts of your videos. :P
As for the drilling, ive found that what works better than etching the holes, is to take a sharp nail and use it as a centre punch - line it up into the middle of the pad, then give it a small tap with e.g. a pair of pliers. Works very well and stops the drill bit wandering off.
The color changing LEDs look really good, I would put white heatshrink around the LED base and the sockets to mask the connectors and create round bloby light sources
For those jobs, I don't use USB sockets anymore. I have just so much low-voltage dc stuff in my room that I got me a huge psu to deliver a trustable 12v rail. And I bought connectors and cables and every device I get gets the matching connector. Now, I have easy access to 12v every time.
For 5v devices, I did the same (smaller connectors), even soldered together a tiny portable 5v supply based on a replacement cellphone battery and a ots power bank circuit I both got on aliexpress.
I can really recommend that technique.
The voltage drop from 12v in the distance of under 5 meters is very acceptable, even my computer is running on 12v (or let me call it 11.5v) now.
I usually put a few drops of baby oil in between the transparency and the dry film and that helps reduce the exposure time because it modifies the refraction index and also it helps stick the two materials really close together
You mentioned soldering micro USBs. I'd love to see a video or get a tip on how to do that because all the ones I come across are surface mounted and seem impossible to replace by hand. Thanks for all the great videos. I have learned so much.
I used to use the green lacquer spray from RS, expose, develop and etch. Not done that for years and years though, I always buy boards with the UV sensitive stuff already on it.
I've actually used a toothbrush to scrub the unexposed film off the copper after developing. It takes quite a bit of work to even touch the cured film. Also: I think Persulfate based etchants require heating to etch in reasonable times: something like 50 degrees C or so (I've not used them).
Clive, I regularly etch my own boards and use yellow Laser PCB transfer paper from eBay and the Iron method, as long as you use some wet and dry paper on the copper surface to give a good key, it work's well and is loads cheaper and quicker than using photo resist film
very neat idea, funny how we made some pcb's at uni with that exact same process you used
I'd love to make one of these!
Wow! Actually really surprised with the result and does look quite like a tree!
If you made this just a bit bigger, it could be modified to take a small lithium battery and charger arrangement at the bottom so it could be operated as a stand-alone unit. The pre-fabricated lithium charge boards on ebay (I've seen them as low as 3 € for 10 pieces including shipping from China, which seems preposterous) usually already include a micro USB port, so you could save yourself the hassle of soldering those tiny little surface mount connections.
I agree, though those fleabay lithium battery stuff really tend to make me cringe.
I've prototyped 0.5mm pitch QFNs before using very fine wire. It's difficult, but not impossible to do!
Nice! Thanks for the video!
The resistors sort of look like roots.... very nice design indeed
It might be worth pointing out (for those new to making PCBs) that there are purpose-made drill bits for putting holes in PCB material (FR4, fiberglass, resin). They're very inexpensive these days, and it is critical to have sharp bits if you intend on making clean holes. FWIW, I use carbide bits in a Proxxon rotary tool & bench press.
This looks very good, I imagine a 'trunk' of about 50 of these with brown and green cables would look incredible. I wonder how long you get away with making the leads to enhance the effect.
Or you could go over the top like I did a long time ago.
www.bigclive.com/bonsai.htm
Well you've trumped anything in my imagination, that's truly amazing. I should make one for a friend who isn't able to keep real bonsai trees in the land of the living.
50 would definitely be worth sending out for manufacturing too.
I love mix of cold and warm light
Looks really nice! I like videos like this, please do more! I wonder if you could also take a look at some of those uv solder masks, see how they work out? Or anything else really to make those pcbs look better, I really liked the look of the white laminated pcbs.
The UV solder mask paint works very well, if you take your time and spread it evenly. Just expect green, sticky fingerprints on everything in your work area though.
It cleans up with alcohol when it's wet, but once it's exposed to UV light, I haven't found anything that will remove it.
Sweet build! Definitely prefer the RGB colour changing LEDs. Would love to see what the effect would be like inside one of those glass craquelar globes you get on Poundland solar garden stake lights.
I tried sodium persulfate myself some time ago.. and well, it doesnt work at all unless you heat it quite a bit. With FeCl i normally have a tray inside a larger tray which is filled with hot water from a boiled kettle, and that works fine. For the Sodium Persulfate i had to use an old roasting tray on a hot plate to get it to work!!
I believe they make a form of the dry-film stuff that has a sticky back with a peel-away plastic protector, so you don't have to worry about lamination or tape or anything like that.
I like that film - it's much better than the laser printer transfer process.
i would love one of them
glad to see that your choice of sponge is the pink one ! foxy would have chosen an orange one
take care using a sponge backed scouring pad. ive found that some brands put some sort of preservative on the sponge (to prevent new sponge funk im guessing) and that stuff can mess up adhesion. ive had issues with it with painting. the ones that are just scotch brite by themselves are fine as far as i know.
I've had good luck with the blue laser-printer sheets but tried the "print on magazine paper then iron on" and had that work OK (not very pretty though).
Toner is basically plastic so it is quite amenable to heat transfer.
Might have to buy some of this stuff.
CPC have a rather nice PCB holder for less than a fiver that you might be interested in under SD02126. The one supplied doesn't have a wingnut end on the spindle but other than than that it's a nice bit of kit. The base is three lengths of steel tube with rubber feet so it should stay put.
Got one of those, they're quite handy but a bit brutal when you have thinner and smaller boards, like .4-mm stuff, and when you have through-hole components right near the edge.
Would have like to see a close-up to see how accurate it is.
I use the Ebay waxy yellow paper with toner transfer, and it leaves holes in the centre of pads. I actually put 0.4mm vias on all pads so the it centres the drill more accurately, and they etch fine.
That opening up everything you buy must be contagious, I find myself doing it all the time now. So far it's all still worked afterwards, but what's life without taking a chance?
If you want a safe light source to use when working with photo resist there are low UV white lights designed for use in museums and art galleries. I used to work in the PCB industry. Back in the 90s we replaced the yellow lights in our clean rooms with low UV white TL tubes. These days LED lighting is probably an even better option.
I use a unit that is fitted with standard longwave blacklight style tubes, so the wavelength is not really hazardous.
Big Clivester is there any chance you could do a design and theory to an end result tutorial?
I have learnt so much already from you and I am also so grateful as I have my my lad wanting to do some with me and maybe he could be the next crazy lighting guru!
Add a photoswitch and standard switch in series on one terminal (probably negative here since it's on the edge of the board) to make that a toggleable nightlight. Could probably also add another switch to it to make it turn on/off on-demand as well
Pretty cool. I think green leds with a few red would look like apple tree. :D
I used a spray can of green photoresist and dried, exposed in sunlight then set in a weak caustic solution.
Simple ferric chloride solution worked well.
au.rs-online.com/web/p/processing-chemicals/1989651/
The good news is that after playing with the stuff for a while it gets very easy to use and is much more forgiving than traditional photosensitive PCBs. With the added benefit that if you do mess up you can clean off the photosensitive coating and put a new one on.
Happy little LEDs.
you need to heat the sodium persulfate solution to about 40 centigrades - then it etches about as fast as ferric chloride, but the solution stays always clear and you can see the board. The solution also does not degrade rapidly when cold again and you can store it at least for weeks and reuse it.
This is why I mill out my boards, no chemicals. Fun design though, cheers
If BigClive says something is frittery to solder then it's beyond the skill of ordinary men.
Very cool, perhaps you could send that pattern to one of the board makers in China where we could order them, and build these lights ourselves. I am really getting into these smaller project lights as I need things to decorate the dash board on our Class A Motor home that we live in over the winter months, when we run from the cold and snow of South Dakota to the wonderland desert of Arizona. I have been watching you for quite some time now, and take your advice on soldering and such. I began with buying solder online since all we can get locally here in the middle of the Dakota's is solder meant for either plumbing, or mending things around the farm, most of which is acid core, and nearly all of which is very thick, and lead less. So I began ordering small spools from China, and had fair luck with it, in fact I began to think I was getting better at it every project. Then this spring, I ran out of the little China spools, and decided to bite the bullet and order some made in the good old US of A. The brand name is American Solder, Rosin Core of course diameter 0.8mm and is marked "FOR INDUSTRIAL USE ONLY" Man is this stuff GREAT!! Suddenly my solder joints look a LOT like yours and I use your examples as the target to reach. What a difference the solder makes this also has TMI on the label and is banned in California according to the packaging because, of course, it contains Lead, and we all know that in California, unlike the rest of the world, one drop of lead means instant birth defects and sudden death! Another great thing about this spool, it is heavy, unlike the big spools from China that have perhaps four layers of cheap solder on them, this reel should last me for a year or better. Found it on Ebay, and i did pay a lot more for it, but it is well worth the extra few bucks to have projects that both look and work as if they were put together by a professional, and not some poor kid in China working for a dollar a week using a nail and candle to solder the joints.
I put the design into DirtyPCBs yesterday to see how well they come out. They offer a share function where others can get a small batch of the PCBs made up. If it's popular I may get a large batch done and add them to my online shop.
Cool, I will have to try and see if I can figure out how to order from them, I think you covered them, or perhaps one of the other electronic folk did at one time or another.
Been looking around their site, keeps sending me to Seeeds, perhaps they are relatives or something but I can't seem to find a place where I can even search for that board.
Yo boss, keep the videos coming
Could use green/brown duct tape or florist tape to wrap the "trunk" and limbs to cover the wires.
Mostly green LEDs for "leaves"with some color changing LEDs in the mix would probably look good too.
I like it leds just got some 10mm ones UV is pretty good
Have you ever tried the toner transfer method? Works a treat for me, even to make some flexible PCBs with copper clad Kapton.
Using ziplock baggies is a great tip for doing single-board runs.
Ferric Chloride, is nasty stuff. Stains everything it comes in contact with and when heated, the fumes will corrode any nearby medal. Had a few tools corrode just being half foot away from fumes alone. Later in time, moved in time to Muriatic Acid and Hydrogen Peroxide. Thanks for showing this method of etching. Which ever one used, heating the solution helps speed up etching. Not sure I would trust the bag seal method, as too easy for leaks and mess. In normal tank, a air aquarium bubbler is good to keep the solution moving about, especially in a taller, more narrow tank (vertical tank).
In addition, I seem to recall, if you have trouble finding Washing Soda, Baking Soda (bicarbonate of soda) can be put on a baking tray or dish, put in the oven for some time with some degree of heat, and converted to Washing Soda. This you will need to confirm as its was a late night reading and never personally tried.
Thanks BigClive for another fantastic video.
This fella agrees with Bicarbonate too: ruclips.net/video/2eRdbvGXkio/видео.html
Very impressive, I've been toying with the idea of that UV film - better than the Seno SN100 lacquer I assume?
I'm curious if it would look better with one LED in the center of the base. Could be nice with some light shining through the wires.
I've been taught the UV exposure technique in school and it always seemed like a tedious and annoying process so I've never actually used it at home. The toner transfer method is far superior to this. Easier to do, faster and needs less equipment. Get the PCB material, a piece of standard photo paper (or special toner transfer paper - but I've never used that one) and print your design onto it. Then just use a clothes iron to stick the toner to the PCB. Use water to remove the paper then etch away.
For etching I just use hydrochloric acid and hydrogen peroxide.
The transfer paper is nicer but more expensive. I suspect there may be a way to make transfer paper possibly involving transparency sheets and hairspray or one of the other common hack materials.
You should build these things with some local Scouts. I made some arduino RFID hike checkpoint things with some Scouts, then the Cubs used them on a hike. Scouts found they like soldering, Cubs found they like working out how to disable vibration sensors...
The center holes on the pads ?
This is due to too long exposure to the UV light. Been there, done that.
Try 60 second and an old tooth brush when developing. Works a treat. The exposed film is very tough when correctly exposed. I can also get traces as fine as 6mil with a 2 mil spacing if I time the exposure correctly. Too much exposure hits the edges of the film under the Negative and hardens it, making it difficult to develop and remove.
I use Ammonium Persulphate all the time. Cleaner and doesn't stink and stain like Ferric Chloride.
All you need to do is submerge the bag with the Ammonium Persulphate and Copper clad board into hot water (80 Deg C) and it would etch the board in 3 mins or 5 mins max if you agitate the solution and you just made the solution. By the time it's finished, the water bath might be down to 60 Deg C.
I use the same solution again and again (It turns Blue due to the copper) and I dispose of it after about 20 boards or if it takes more than 10 minutes to etch.
Shelf life ? I store the used solution in an empty plastic Coke bottle, squeeze out the air and cap it between use. I can go back to it in 1 year and it is as good as gold. I absolutely hate Ferric Chloride. Very dirty, smelly, staining etchant. It's the pits !
I love being able to see the copper fade away in front of my eyes and the second thing is you can keep an eye on 6 mil traces with 2 mil spacing and "See" the 2 mil gap appear. With Ferric Chloride, because you can see bugger all, you have a good chance of over etching fine traces under the tracks and actually dissolve fine traces or cause the "T" syndrome.
Give it a try. Once you have, you will never use that Worcestershire Sauce...Oops, sorry, Ferric Chloride again !
One could also use a sharp center punch to mark the hole centers.
dlock2k: but it couldn't be as precisely placed as a printed dot, i wouldn't think
In this case it's most probably due to Clive not removing the clear film layer and exposing through it - it's a small dot and light can go under it at an angle from every side.
I'm using proper photo films and they don't stick to the emulsion, Clive's film has a coating to accept ink I believe and this may be the cause.
You are not supposed to remove the top film until you are going to develop it.
I have worked with All types of films (Dupont, 3M, no name brands etc) for 30 years. You are meant to keep the 1 micron film covering the emulsion on to prevent the air affecting the emulsions capability to be removed cleanly. I used to work for a large PCB manufacturing house making PCB's for NEC telecomunications equipment. Up to 20 layer microwave transmitter boards. This is why it can stick to the negative or even pull off the toner when you use transparencies.
Never had an issue with pad holes right down to 5 mil home use unless exposed too long. 20 seconds either way can be too much or too little.
This Chinese film definitely isn't 1 micron. Perhaps Clive could cut his into pieces and measure say 30 of them with a micrometer or at least calipers.
No experience in professional PCB making, but 20 years of experience in printing industry and any film between the photofilm and the emulsion, be it on an offset printing plate, a silkscreen or a flexo photopolymer plaate is unheard of. Imaging is done under a vacuum press to ensure maximum contact between the photofilm and the emulsion, because even a tiny amount of distance results in a blurred image and consequently loss of detail.
I'd buy a kit to make that, very cool
Re the holes. With the way the light shines, it is probably getting around those small dots and exposing the resist underneath. If you make them a little bigger, it should compensate. If you could measure the other elements of your circuits, you'd probably find they were a little bit smaller than from the print also. There's a word for this but can't remember what it is. (It's "undercut"). It can also be caused by the print not being tight against the resist but could also be caused by the thickness of the resist itself and is definitely inherent in your exposure setup anyway (Not that I'm criticizing it. Well, I guess I am but hopefully in a constructive way). I don't do photo-etch PCBs but I do screenprint sometimes and the light source is several feet from the screen which gives a more parallel light exposure.
how do resistors respond to flock the green faux grass used in train sets cos that could be turned into a really really nice tree desk illumination
Just a thought - the outer rail needn't have so much copper removed (and the bigclivedotcom text could be in negative) - less precise drilling and it'll save on ferric chloride too ;-)
Funky build :o)
I used Ferric Chloride etchant once and I hated the stuff, makes a big mess and stains everything it touches. I now use Ammonium Persulfate and it works much better. It does slow down and turn blue as it gets loaded up with copper, and doesn't work very fast unless its heated in a bubble tank to about 40 C. Thank you for making the video, I've seen that same resist film on ebay and wondered how well it worked. What laminator did you use?
Your soldering 'design' Looks Very Aztecish, Nice! ~ So, Are you going to try a board displaying your new artful likeness, and 'highlight' your beard with a Fiber optic array?
what do you call the pins you crimp on the wires? i need to put a 3 pin fan header on a pc fan and i have a crimper but i cant find what those pins are that people dont want to charge a fortune for a little amount, cheers again mate and another brilliant video
When shipping the dry film I sell (locally in NZ), I send as cut sheets but each is allowed to roll itself naturally, and is sent in a box so it doesn't get crushed, a few years ago I tried sending as flat cut sheets, but that was such a hassle trying to get them flat and packed.
Then I tried rolling them around long lollypop sticks and thought I was onto a real winner there as they could be shipped in an envelope, bad idea because after a few days they were all wrinkly where the polymer had "flowed" and taken on something of a texture. So where was I, yes, I find it's best to let them assume their own natural rolled state, when first cut they end up about 15mm diameter and then over some days in the cool they naturally constict themselves down to about 6mm (18cm long sheets)
For applying it, I usually use a clothes iron actually rather than a laminator, the clothes iron set quite low gives more control I feel, although more it's just because I can't be bothered digging out the laminator. Recently also similarly to how you did it I've used the water application method, but my hot air gun to do the fixing, again only modestly hot, with the squeegee.
Anyway, here's my tips-and-tricks for what it's worth... sparks.gogo.co.nz/dry-film-tips.pdf
I was playing with the film last night and so far the easiest application was with a very slight misting of water, the felt tipped vinyl squeegee and a hair dryer to apply the heat while squeegeeing the film on. It was fast and easy with no laminator required. I also noticed that even with the ripples in the squashed gel it produced a perfect exposure and etch anyway.
Cool, I had been wondering if a hair-dryer would do the trick.