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Actually, I tried a couple of others that people suggested, but ended up sticking with UGS for now, it's actually not all that bad taking everything into account. Maybe if I get motivated I will try some others at some point in the future.

Thanks for the comment! I am glad to hear the video might be of some help. Good luck with your rebuild!

Actually I use self-ground HSS but a lot, because they give a better finish and often better form factor. You can see them in use in some later videos. But, I still use those cheap carbide inserts too when I am being lazy, the finish is a compromise, but they are pretty convenient.

Never too late to learn if you have an interest.

Don't get me started.....

Unfortunately the yellow ABS I had would not print the center bit, so this is what you get. Thankfully I am the only person who uses this, and my human instincts just have me fist slamming the button in emergencies, I don't seem to have much time to check the colour in such cases.

Didn't notice I was going the wrong way, usually I am pretty careful about that. Thankfully it worked out ok.

Glad you liked it, and thanks for taking the time to leave a comment!

Thanks for watching and thanks for the nag! BTW: How did you find this video?

@@ForOurGood Hackaday of course! :)

@@youtubasoarus I never even knew... Thanks for letting me know!

I can pretty conclusively say that acceleration does not play a notable role when using this process. I was in fact worried about that given the CNC3018 with its cheap lead screw accelerates pretty slowly. Undoubtably there is minor affect, but it is not noticeable from my experience. The key issues about clearing the resin from the pads without burning them off the board, comes down to a very simple calculation. That is how much “heat over time” you inject into the pad, and how much “heat over time” the pad can dissipate. If you add far more heat than the pad can dissipate in a given timeframe, then that will result in enough heat build up to eventually burn the substrate (And on top of all that, of course you’ll always need enough laser power to clear the resin). The best solution I have found is to use active cooling, such as air-assist, by doing that you can stop the pad from building up too much heat, meaning you can get away with a much higher power level that allows you to clear all pads with a single power setting. If you do not have air-assist, then the only other option is to break up the pads into different groups/jobs, applying an appropriate power level, depending on how well you expect them to be able to dissipate/cope with heat. Naturally this requires experience and good judgement to get this right, that is why I recommend air-assist as demonstrated in this video. Thanks for your comment and I hope you enjoy the video.

​@@ForOurGoodif so then that's very different from my result. I got full blast of air assist on all the time but can still see very clearly that the corners will get burned much more than s straight line. There are some settings to help even out the laser power but then it will reduce the power by a lot and still somehow doesn't get that consistency. There is one more thing is that if I don't align the laser well enough and some how burn into the resin area beneath then 100% guarantee that the pads will peel off. Those got me so frustrated with the laser so I developed my own process using printed light mask to cure the solder mask. I've been having consistent results since then and much simpler process and less tedious. Hopefully I can share it some days but I'm quite lazy with making videos and busy with out projects also. But I'm very glad that you succeed with your process. I hope more people will get into this so someone will try to fix FlatCAM. 😅

@@TinNguyen-uu2tr If the acceleration is that slow, then there must be a problem with your settings of your CNC (mine is 500mm/sec/sec for all axis) Also, using good FlatCAM settings is pretty critical, and that's why I discussed in detail in this video. Finally, maintaining perfect alignment is also critical, which is why I came up with the new alignment method which is working very good (alignment pins just don't provide enough precision). Finally, you can't have the laser set too hot, there is a limit to how much air assist can help. In any case, I am glad you came up with a process that is working for you, I am very much looking forward to your video 👍😁

After seeing the great results of the silkscreen, I also had various ideas about how I could apply this for different purposes, maybe even trying to set the positive etch pattern with it. Setting the resin around the pads should also be plausible. Naturally, I would need to switch to the 10sec Mechanic resin for everything, and of course this is going to mean much much longer jobs (although it may be possible for it to be faster if the resin is not a couple of years old, like mine is). Then there is the question as to if the result would be cleaner using an expose method vs the burn method, and how reliable/consistent that might be given the expose method is a little more finicky, compared to burn method that just works and gives a consistent result every single time. For a silkscreen, +/- 10% thickness variation does not make a big difference, just as long as you can get it to stick, but a for a etch resist or pad clearing operation, this could be a real problem when working with small stuff. I also have other ideas about ways to clear the pads by laying something down in advance that could easily be removed later, along with any resin on top, but this has not progress beyond the thinking stage at this time, I generally think this might be a non-starter. For now, I am super happy with the results I am getting with the current process, and I probably make it look harder to do than it actually is, this is mainly because I had a lot of bad experiences before finally getting to the point where it actually works well. I still have a few improvements to my process in mind, but mostly minor tweaks to materials, tools and methods. Even so, I think at some point I will experiment with the resin expose method more, at least to test my assumptions, and see if this might actually be something practical/possible/worthwhile to do more with. As for the oven, I did actually think about doing something like that for this video, but in the end, I deemed it not a pressing concern, that old Panasonic clothes iron is doing what I need it to do for now. Maybe one day!

@@ForOurGood Cool, I figured you'd likely at least thought about it. Btw, what power is your laser? I've got a dinky little 5w laser that is essentially useless for anything other than marking things or exposing resin, and I really need to find a better one.

The laser I am using is a “LaserTree Gold 450nm 40W-Pro 12V 20mm Fixed Focus Laser”, apparently it puts out less than 10 watts of optical power in reality. I highly recommend getting one with an air assist nozzle.

@@ForOurGood Cheers, I'll have a look for a similar unit.

Hi Giovanni, I am sorry you have some trouble, that is a part of learning, but please be assurred that many other people have confirmed the menu works fine. I don't release the code intentionally, to increase the chance you will learn more by doing, and solving the problems yourself. I suggest you follow the video step by step, confirming that the results you are getting at each step exactly match what I am demonstrating, and if at any point it does not match, then focus on that area, and see if you can solve the problem. Writing code is not always fun, but it can be rewarding when you understand and get things to work as you expected. Good luck!

Just in case you are not taking the piss, and simply missed the section, I do talk about this at 2:24:30 Glad you liked the video! 😁 I am feeling pretty buggered after making that one.

@ForOurGood I managed to comment just before I got to you mentioning liquid tin, so that’s on me for jumping the gun. 🤦🏼‍♂️ no piss was harmed in the making of my comment. 😜

@ForOurGood I’m not surprised you are exhausted after that movie length video, I felt tired after making my latest 15 minute video. 🤦🏼‍♂️

@@ForOurGood I just got to the end, your silk screen imo looks better than the manufactured PCB silk screen. Iirc the cheaper boards use inkjet printing.

Btw, you should submit this to hackaday if you haven’t, always pcb makers lurking there :)

The title is unlikely to help much, at best my videos top out at about 20K after a few years, worst cast a couple of hundred views. Basically, TH-cam does not promote my videos in any sensible way, I laugh when I see my videos continuously recommended on things like Polish Opera videos, then TH-cam Studio gives advice that the poor click rate is because my thumbnails suck... yeah right.. The conspiracy theorist in me makes me want to say this is because I disabled ads for all my videos, but TH-cam says its policy is that this makes no difference, so it likely is because my videos are not so great after all. Anyway, impressions for this video have already dropped to zero after 5 days. (Rant over). BTW, I originally got interested again in making PCB’s when I saw a Wegstr video, and was fully expecting to be milling PCB’s, and in my second episode made a sincere effort to do just that. But milling PCB’s on my 3018 just was just not doing it for me, so I quickly decided to try a different path. Again, likely due to some bias, I really like this process, and at least comes to etching an amazing result, it’s just so damn reliable and stupid proof. Once you take the mechanical interaction out between the CNC and the PCB, it totally transforms what a cheap CNC is capable of delivering. As a contrast, a Wegstr PCB mill is selling for $3.7K shipped, for me that does not seem like the typical DIY’er spend, maybe it is ok for some people. Let me know how you go with the silkscreen, and thanks for the comment!

@@robindebreuil Thanks for the advice, but I am not so good at self-promotion, I just throw it out there and see what happens. I don’t even bother doing the obligatory beg for likes or subscriptions in my videos anymore.

@@ForOurGood Ha yeah, right there with you, promotion is unpleasant work. The Wegstr machine seems amazing, but yeah, different thing. I’m working towards a small dedicated machine for simple PCBs. There are so many ways to remove copper, it makes for an interesting obsession. Very inspired by your dedication to the craft here, thanks for sharing it in such a detailed manner.

Yeah, sorry for the long video, but it seems tutorials do much better if they are not split up. Even so, I am glad you found it interesting. I did actually try using plastic sheet, but I could not get a clean cut... more of a melty twisty result... I didn't use matte black paint, but I did try a matt black paint pen if I remember correctly. The feature size also is a challenge, with a paper label I could barely eek out the 0.2mm width required for the QFN20 package, so I sort of came to the conclusion that trying to do that with plastic sheet would simply be futile. What sort of resolution are you getting? Do you know what type fo plastic the sheet is made of? Currently, I am usually only doing one or two PCB's with a given stencil, so it is not really a big deal if it is not reusable (of course that would be nice if it was reusable). What is more of a concern, is getting the correct thickness (currently good), nice clean edges (currently not great), smooth surface (currently not really), required resolution (currently passable) and relatively sturdy (currently sturdy enough for a couple of uses, but not really sturdy as such) In know the locating of the stencil, is doable without an adhesive backing, have seen this in another persons video, so I am not super worried about that aspect either way. Thanks for taking the time to comment and provide some info too!

Just noticed your "mouse-bites" point, not sure why I missed it first read, but I will try to keep that in mind, thanks! As for amount of hours in production.. yep, don't want to think about it much, especially because I already know the video will not really get that many views. But they say, about an hour per minute, is what it takes just to properly edit a TH-cam video.... but that excludes everything else

@@ForOurGood The first plastic stencil I made was from the diffuser sheet from a cracked LCD monitor. Since then I have used old school transparency sheets made for laser printers. I found two lower power cuts are better than one high power. Also I cut the outline only and not the field area.

@@mitchellhw2006 Got it, thanks! I will see if I can find something similar and give it a go. I actually used to use those laser printer transparencies back in the 90's when I was making PCB's back then, I guess it makes sense that they are somewhat heat tolerant.

You can find the code as a response to one of the older comments below! Hope that helps.

@@ForOurGood Thank you, it must have been a syntax error. question, how can i get the program to do something base on the screen option it landed...i'm rather new to this. so how would the program know the choice the user made..i want to be able to execute code based on let's say the submenu choice 1?

Sorry, I don't think I have a helpful answer to this question. For the very basics, maybe some other channels have a better video, there are also many other good resources available out there to learn from. I hope you succeed in what you are trying to do!

There are plenty of resources out there if you want to learn electronic. You don’t need to learn absolutely everything to be able to start making your own PCB’s. Start small, learn the very basics, and do some testing to see if what you learnt makes sense with the results you get. Each small piece of knowledge is a building block you can use to improve your skills as you go, and in this way, it is very similar to learning writing code. I started writing code at the age of 12, but I did not start doing anything with electronics until age 17, but learning code helps you with structural thinking, and that helped allot when learning electronics. Good luck!

Seems I am a little late to the game with regards to pre-baking UV resin before exposure, but it does not exactly seem to be common practice either. Actually, just yesterday I noticed on an Ali-Express store with the Mechanic UV resin, a set on instructions indicating both pre & post baking as a part of the process (the instructions are really not that clear however, and they talk about baking times of 50~60mins for each, which seems excessive). Unfortunately, I see no such similar instruction for the green WNB UV resin I am using. I also didn’t see a specific improvement in curing time with the Mechanic UV resin after baking, even though the viewer who commented indicated instant curing was achievable. The clear benefit I did get was a quality improvement, which in that case is the most critical thing anyway. It is possible that either my testing was not thorough enough, or my UV resin has just aged poorly (it is about 2 years old, and Mechanic UV resin is stated as a 12-month shelf life) Even so, I was already thinking to give pre-baking a try with my green WNB UV resin, so I will likely do that next time, and see how it affects the curing time (30mins is way too long). Don’t think I will be hitting with a heat gun however, that would likely disturb the finish, so I will probably try the hotplate, basically using a similar method to what I am already doing with the Mechanic UV resin. Would be nice to get the time to less than 15mins in total, otherwise it is probably not worth the extra messing around. Thanks for the comment!

The process is actually relatively cheap, considering the end results that can be achieved. If you are smart with the purchases, I expect you could get started for around about $300USD. You also need to keep in mind that the CNC is a multi-functional device, and you can use it for things beyond just making simple PCB’s. Thanks for the comment!

I tried for a while, and in the end gave up. Maybe I was doing it wrong or something. Another viewer also left a comment about how to do this, so I will give it another go next time!

Sorry, ignore what I said before. I can't remember if I specifically tried moving to the bottom left, I sort of think so. I did move it around a bit and tried a few things. I will try bottom left next time.

@@ForOurGood I'm not the sharpest tool in the shed, so you'll figure it out, I'm sure. That said, I haven't tried it in KiCad v8 yet, but in v7 it was straightforward.

@@ForOurGood Bottom left gives you a positive X and Y Axis, which makes things simpler for sure. :)

There are some pretty close up shots at the end, so you can judge for yourself. From what I am seeing, they look and work very well. I have also been using similar boards, however made with my older process, for a number of years now without a problem. Thanks for the question!

@@ForOurGood good to hear. the result looks quite good, it just looks like there's a very high layer of resin. But if it works out, it works out :D I just use black spray paint to cover the board and use the same 3018 with the laser it came with. But i only use it for emergency boards... so i'm not very picky :D

@@Error404_Handle I think the magnification method I use makes it seem thicker than it really is. Laying down the resin with the silkscreen results in a super thin layer in reality, and even with 2 layers it is still pretty thin.

@@ForOurGood that and maybe the sharp angle that's left after the laser burns the resin off. Definitely could be the reason why it looks so thick. But great job either way.

Thanks for watching & the nice comment! 😉 You are clearly one of the lucky few to have somehow connected my channel, because I don’t get much love from TH-cam, that is for sure... Clearly I am doing something wrong.... 😐 And just for a laugh, TH-cam just yesterday recommended me to watch a 3-year old video on how to make PCBs, this is a 10 minute video which shows how to make PCB’s just like I was making them back in 1993.. it has 1.4million views... so who ever said life is fair!

The laser I am using is a “LaserTree Gold 450nm 40W-Pro 12V 20mm Fixed Focus Laser”, apparently it puts out less than 10 watts of optical power in reality. I highly recommend getting one with an air assist nozzle. Sorry, I am not sure I understand your question regarding the PCB cutout. The laser is not powerful enough to cut through the central glass fibers of the board, which is why I need to laser cut on both sides of the board. I show cutting the front of the board at timestamp (1:49:40), and the rear of the board at timestamp (2:08:25). The final step is to snap it out, breaking the central glass fibers, as shown in timestamp (2:35:10) Thanks for the comment!

@@ForOurGood Flip, sorry I somehow missed you cutting the outline on back of the board. Thats what I was asking about. Thanks for the info. I have a creality 10W (with air assist) upgrade kit fitted to my ender 3 v2 neo. So hopefully, following your steps I should be able to acheive the same. I thought my laser might be too weak to do this. Thanks again.

@@arthureschner9319 no worries, the video is pretty long, so not surprising if people miss bits here and there. Anyway, sounds like your laser will do the job, so good luck with that 👍

You are very welcome, thanks for the comment!

Ha Ha, yep, I reckon your probably right, most people will just live with their mistakes after the first order, it’s gotta be pretty disappointing😐. Personally, I could not stomach the stress of getting it wrong (or likely getting it wrong), and then having to live with it, which is part of the reason I have never taken the step of ordering a board from China myself 😊. Actually, even in a professional environment, I could rarely justify going more than one revision before needing to put a board into the required operation (my requirements were never mass production however, max 100 or so boards). The great thing about surface mount, is that with the help of the hotplate, it is super easy and fast to reuse components, so that definitely takes the sting out of the idea of having to redo a DIY PCB too. Using my new process, I honestly believe I would be inclined to do the necessary iterations to at least get the circuit design and track layout of the PCB correct. Thanks as always for the comment and support!

I did mess around with that for a while, but failed to get it to work. It's more than likely that I checked the wrong box or something. Next time I make a PCB, I will be sure to give it another try. Thanks!

@@ForOurGood First of all, and I should of said this before, but thank you for all the effort you put into your method and for documenting the process as well as your journey to get there. The end result is very impressive and is nearly indistinguishable from purchased boards. I personally made my first pcb over 40 years ago using pre-sensitize coper clad boards and photocopies of artwork on overhead transparency papers while exposing them to sunlight. Since then, I've tried lots of different methods, including toner transfer, resist pen plotting, and isolation milling. All to varying degrees of success, and at this point I've all but given in to just using fast turnaround Chinese vendors. Your method has rekindled my desire to produce my own pcbs for first article prototyping and same day iteration testing, as such I would be most interested in learning the optical power of your laser module. I believe this is just the excuse that I needed to justify adding a laser to my CNC machine. With regards to the origin issue, the tic box you are looking for is in the upper right quadrant of the plot dialog and is labeled "Use drill/place file origin".

Wow, 40 years ago, I did my first probably in 1991, though I have probably had a 15 or so year hiatus before my latest attempts were started, either way, you have got me beat! I am glad to hear that the video might actually stimulate someone to get back into the hobby, so thanks for the comment! The laser I am using is a “LaserTree Gold 450nm 40W-Pro 12V 20mm Fixed Focus Laser”, apparently it puts out less than 10 watts of optical power in reality. I bought mine a couple of years back on Ali-Express, so it is likely this exact model is not sold now, but I am sure you will find something similar, though I do recommend you buy one with an air assist nozzle included, even if you don’t plan to use it immediately.

Give it a try! I guarantee you will be surprised by the results. Thanks for the comment!

What I am trying to demonstrate here is different way to achieve high precision PCB locating, that is easy to replicate, even with all different sizes of blank PCB stock. I have actually been using alignment pins right up until recently (see my earlier videos), including going to the effort of machining my own precision sized pins to ensure an exact fit, but it just does not work good enough for this level of high-resolution PCB, and that is why I came up with these new methods. The reality is, that it is extremely difficult, actually nearly impossible, to reliably get the repeat fitment accuracy of less than +/- 0.01mm, using the locating pin method. Thanks for the comment!

I hope you and your fellow engineering students can now solve your pad clearing problems, good luck and thanks for the comment!

Vias vias vias.. sigh.. every one wants an easy solution for this.. not at all feeling confident with this part of the problem, but I am still thinking about it. You never know 😉 Thanks for the comment!

Glad you liked it! Thanks for the comment!

====================== [Single Sided PCB Process] ====================== 1. UV Resin Coat PCB - If PCB surface has notable corrosion or scratches, use Scotch Brite to create wire brush finish first - Use metal polish (e.g. Pikal or Brasso) to polish to a high shine finish - Using tissue paper, clean thoroughly with IPA and dry with (maintain dust free from here) - Apply UV Resin and use small spatula to push into the entire surface first - Use a piece of Mono thread #150 silkscreen mesh to level surface - Remove silkscreen mesh, INSPECT and REDO as required (minimize bubbles or dust particles) - ALLOW TO SETTLE for 2 minutes (keep covered to avoid dust!) - Expose with UV lamp for 30 minutes (WNB UV-W100 Green UV resin) > Note: Store the silkscreen mesh in a dark & dust free place so it can be used again in Step#5 > Note: Silkscreen mesh can also be washed in IPA and reused, but the cost/benefit should be considered case by case > Note: If you are working with a large PCB, then consider putting the mesh in a frame or mesh to make handling easier 2. Affix PCB Locating Guides - Make 4 "L" shaped PCB corner brackets from PCB offcuts - Cover PCB corner brackets with masking tape, leaving PCB contact surface bare - Cover PCB working area with masking tape with generous margins - Clamp working PCB firmly in place, centered to the masked area - While applying pressure to corner bracket, add CA glue to outside edge - Apply CA glue accelerator to lock corner bracket in place - Repeat above 2 steps for all 4 corners - Leave for 5 minutes to allow CA glue to fully set - Remove PCB - Lightly clean CA glue accelerator residue from the PCB with IPA - Replace PCB and check for movement. (Redo if not a positive/firm fit) - Clamp working PCB firmly in place. > Note: A different locating method may be used, as long as it allows for accurate re-installation of the PCB during the job 3. Create Location Reference - Make locating marker from UV resin coated PCB offcut (min 10W x 40H) - Determine location of locating marker, close but allows PCB to be flipped. - Make sure edges and shape is square for both location marker, and PCB. Adjust with file as need be. - Apply masking tape to cover area where locating marker will be glued (min 25W x 50H) - Place locating marker in the center of the masking tape, oriented square to CNC - While applying pressure to locating marker, add CA glue to margin - Apply CA glue accelerator to lock locating marker in place - Leave for 5 minutes to allow CA glue to fully set - Lightly clean marker with IPA - Home CNC & Set XY to zero - Probe Z-Height of work PCB surface and set laser to correct focus height - Locate laser relative to lower left corner of locating marker X+3mm Y+3mm - TAKE NOTE OF OFFSET COORDINATES (will refer to as "LM_OFFSET" hereon) - Set X & Y coordinates to zero - Laser burn reference markings onto surface (use "Laser_Make_Reference.nc") - Move the laser to zero X&Y point for the work PCB - TAKE NOTE OF OFFSET COORDINATES (will refer to as "PCB_OFFSET" hereon) - Set X & Y coordinates to zero 4. Laser Clear Etch Area & Etching - Prepare Ferric Chloride by warming in boiled water bath - Load G-Code file "??-?_Cu.gbr_sub_edit_iso_combined_cnc.nc" - Run G-code to laser clear area to be etched - Remove PCB and lightly wash in IPA using fine hair toothbrush, then dry. - Place PCB in Ferric Chloride, continually agitate, occasional brushing. - At 5 minutes observer carefully until all visible copper has been removed - Wash in water, and check with microscope or zoom camera for residual copper - Repeat etching in 30>45 second intervals until etched enough (do not over etch!) - Clean with IPA and fine toothbrush, then dry with dabbing tissue paper 5. UV Resin Top Coat & Print PCB Silkscreen - Repeat Step#1 procedures to apply top coat (Use silkscreen cutoff for small area) - Wash thoroughly with IPA and dry with tissue paper (maintain dust free from here) - Apply UV Resin and use small spatula to push into surface (Fast UV curing resin!) - Use a piece of Mono thread #150 silkscreen mesh to level surface Note: Use as little UV resin as possible and create a thin even coat - Remove silkscreen mesh, INSPECT and REDO as required (minimize bubbles or dust particles) - ALLOW TO SETTLE for 2 minutes (keep covered to avoid dust!) - Use hotplate to heat PCB for 10-minutes @80degC then cool to 50degC Note: Finish should look flat and somewhat dull after this process - Mount PCB in CNC and clamp firmly in place. - Load G-Code file "??-?_Silkscreen.gbr_iso_combined_mt_paint_cnc.nc" - Run G-code to expose the PCB Silkscreen pattern - Remove PCB from CNC - Use IPA soaked tissue to dab off majority of unrequired resin - Scrub with IPA and fine toothbrush to reveal the PCB Silkscreen details Note: Important to scrub pretty hard to test adhesions, dont be scared to scrub Note: If the some or all of the PCB fall off, redo with higher power settings - Final clean with IPA and dry with tissue paper - Expose with UV lamp for 1 minute (Mechanic UVH900-WY White UV resin) 6. Laser Clear Pads, Laser Clear Outline & Laser Cut PCB @45% depth - Mount PCB in CNC and clamp firmly in place. - Load G-Code file "??-?_Mask.gbr_sub_iso_combined_mt_paint_cnc.nc" - Run G-code to laser clear the pads while using STRONG AIR ASSIST for cooling pads Note: If air-assist is not available, then use the Gerbal editor in Flatcam to split up the pad clearing operation into 2 or more files, with pads having smaller thermal capacity, using lower power levels. (avoids burning PCB substrate) - Load G-Code file "??-User_8.gbr_iso_combined_mt_paint_cnc.nc" - Run G-code to laser clear the PCB edge outline (NO air assist needed from here) - Load G-Code file "??-User_9.gbr_iso_combined_cnc.nc" - Run G-code to laser cut the PCB - Remove PCB and scrub the pads clean using IPA and fine toothbrush, then dry. 7. Install & Align Spindle, Setup PCB for Drilling - Remove laser and install spindle - Home CNC & Set XY to zero - Install 1mm drill in the spindle - Probe Z-Height of locating marker - Move CNC to LM_OFFSET X&Y coordinates and then move Z to G0Z0.3 - Adjust XY position by eye to be centered with location cross mark - Set X & Y coordinates to zero - Move CNC to coordinates G0X0Y4 - Set X & Y coordinates to zero a - Drill test holes in locating marker (use "Drill_Align_Test.nc") b - Magnify and inspect marks and determine X & Y adjustment (COMPENSATE INSIDE HOLE DISTANCE!) c - Move to X0Y4 adding the determined adjustment amount for X & Y (typically +/- 0.01>0.1) d - Set X & Y coordinates to zero Note: If the drilled hole has an ugly burr, consider changing to a new 1mm drill. - Repeat steps "a" thru "d" until good alignment achieved - Move CNC to coordinates to G0X0Y0 then G0Z0.3 - Move CNC by 1mm steps until centered with location cross mark - Set X & Y coordinates to zero - Move CNC to coordinates to G0Z15 to ensure the drill will be clear - Move CNC to PCB_OFFSET X&Y coordinates - Set X & Y coordinates to zero - Re-install PCB with 0.2mm waste sheet underneath, ready for drilling - Probe Z-Height of work PCB 8. Drill Alignment Holes - Load G-Code file "Alignment Drills_cnc.nc" - Run G-code to drill 1mm alignment holes in work PCB - Use a small drill to bevel the copper edges (REMOVE ANY COPPER BURR!) 9. Drill PCB Through Holes - Ensure all drills to be used have collet stoppers adjusted to same height - Load G-Code file "??-PTH.drl_cnc.nc" - Install first drill in sequence in the spindle - Probe Z-Height of work PCB (if not already done) - Move the spindle to the location of the first hole at a Z height 0.2mm - Inspect drill location, if noticable error exists,then adjust the origin to compensate - Run G-code to drill holes in work PCB, changing drill bit as per the drill sequence Note: Alignment holes are made into a copper surface, but PCB holes will drill into softer resin Blunt drills and/or Z axis play, can cause the holes drilled in copper to shift position This likely will result in the PCB holes being drilled slightly off center due to alignment error For consisent errors, consider adding an adjustment amount to the origin before drilling PCB holes For inconsistent errors, don't substract holes from CU & Mask layers in Flatcam prep (i.e. don't etch holes)

10. Install & Align Laser - Remove spindle and install laser - Home CNC & Set XY to zero - Probe Z-Height of locating marker and set laser to correct focus height - Move CNC to LM_OFFSET X&Y coordinates - Adjust XY position by eye to be centered with location cross mark - Set X & Y coordinates to zero - Move CNC to coordinates G0X0Y4 - Set X & Y coordinates to zero a - Burn test marks in locating marker (use "Laser_Align_Test.nc") b - Magnify and inspect marks and determine X & Y adjustment (COMPENSATE OUTSIDE CIRCLE DISTANCE!) c - Move to G0X0Y4 adding the determined adjustment amount for X & Y (typically +/- 0.01>0.1) d - Set X & Y coordinates to zero - Repeat steps "a" thru "d" until good alignment achieved - Move CNC to coordinates to G0X0Y0 - Move CNC by 1mm steps until centered with location cross mark - Set X & Y coordinates to zero - Move CNC to coordinates to G0Z10 to ensure the laser will be clear - Move CNC to PCB_OFFSET X&Y coordinates - Set X & Y coordinates to zero 11. Burn Alignment Marks, Flip & Align PCB - Remove PCB, remove waste sheet, and re-install PCB without waste sheet - Check alignment holes are all clean and clear - Probe Z-Height of MOUNTING surface (i.e. waste board) - Load G-Code file "Alignment Drills_conv_edit_iso_combined_cnc.nc" - Run G-code to burn alignment marks into the masking tape on the mounting surface - Remove PCB - Remove Locating Guides, being careful not to disturb the alignment marks - Flip PCB backside up, and using magnification, align alignment holes and marks - Clamp PCB firmly in place - Probe Z-Height of PCB surface 12. Back Side PCB Markings & Laser Cut - Load G-Code file "??-B_Silkscreen.gbr_iso_combined_mt_paint_cnc.nc" - Run G-code to mark the bare P - For symmetric PCB -> Load G-Code File "??-User_9.gbr_iso_combined_cnc.nc" - For asymmetric PCB -> Load G-Code File "??-User_9.gbr_1_iso_combined_cnc.nc" - Run G-code to laser cut the PCB - Masking tape, locating guides and reference can be removed 13. Laser Cut SMD Solder Paste Stencil (If SMD is used in design) - Mount bare copper clad PCB in CNC as working surface - Apply masking tape to the bare PCB over area larger than the stencil - Load G-Code File "??-F_Paste.gbr_edit_iso_combined_cnc.nc" - Set the XY origin of the CNC so the stencil will be burnt at the center of the masking tape - Cut out 2 pieces of white weak adhesive label sheet large enough for the stencil - Carefully apply the FIRST layer of label sheet to the center of the masking tape - Use Scotch Brite to dull surface of the FIRST layer of label sheet, clean lightly with IPA - Probe Z-Height of the FIRST layer of label sheet - Run G-code to cut the stencil design into the FIRST layer of label sheet - Now stick the SECOND piece of label sheet carefully on top of the FIRST layer - Use Scotch Brite to dull surface of the SECOND layer of label sheet, clean lightly with IPA - Run G-code to cut the stencil design into the SECOND layer of label sheet - Carefully remove COMBINED layers from masking tape, leaving cutout areas on the masking tape - REDUCE STENCIL ADHESION by pressing sticky side to your fingers a few times (need only minimal adhesion) 14. Prepare Pads for Soldering - Magnify and inspect, using a pin tip to remove any obvious resin remaining on pads - Use fine toothbrush and metal polish (Pikal/Brasso) to bring pads to a high shine > When polishing, focus on scrubbing inside the pad cavities cut into the resin > Rotate the PCB and polish a couple of times from different angles to ensure all areas covered > Take care with this step, it's CRITICAL to remove residue from pads to get good solder take up - Scrub the pads clean using IPA and fine toothbrush, then dry. - Magnify and inspect, confirming all pads are highly reflective. Repeat polishing as needed > Note: If the PCB was polished well in Step#1, then getting a good shine on the pads should be easy. 15. SMD Assembly Process (If SMD is used in design) - Affix the stencil to the PCB so it is accurately aligned with the pads, then press down firmly - Magnify and inspect stencil, ensuring all holes are clear, use pin tip to clear as needed - Apply solder paste into stencil cavities with spatula, press in hard, scrape of excess - Carefully remove Paste Stencil so the paste remains in the PCB undisturbed - Place all SMD components onto PCB - Place PCB on hotplate and PRE-HEAT to just below solder paste melting point, hold for 2min > for 138degC solder paste this is approximately 125degC > for 183degC solder paste this is approximately 145degC - Raise the hotplate to the REFLOW temperature for the solder paste, hold for 1min > for 138degC solder paste this is approximately between 150degC > 150degC > for 183degC solder paste this is approximately between 205degC > 225degC - Nudge any out of place components - Carefully remove from hotplate and allow to cool naturally (do not cool quickly) - Clean with IPA and fine toothbrush, then dry. - Inspect with magnification, remove any unwanted solder beads & further clean as need be 16. Snap Out PCB & Clean Edges - Repeatedly bend waste part of PCB around laser cut edges of PCB, and snap it out - Use fine file to clean up outside edge of PCB to align cleanly with laser burns - Clean with IPA and fine toothbrush, then dry. 17. Install & Solder Through Hole Parts (If thru-hole components used in design) - Install, solder and trim wires of any through hole components - Clean with IPA and fine toothbrush, then dry. ====================== [Double Sided PCB Process] ====================== a) Step 1: UV Resin coat BOTH sides of the PCB (One side at a time of course...) b) Steps 2 thru 10, Skipping Step-9: Alignment & Front Side Process (Skip drilling PCB Holes) c) Steps 11 & Step 2 Combined: Flip PCB, Align and add new Locating Guides for back side processing d) Steps 4 thru 9, Skipping Step-8: Back Side Process* & Drill PCB Holes (Skip drilling Locating Holes again) e) Steps 13 thru 17: Assemble PCB (Note: Manually solder on back side components as need be) * When etching the back side of the PCB, make sure to protect front side with tape or adhesive sheet

=================== [ KiCad Layers & Creating Files ] =================== @@@@@ Single Sided PCB @@@@@ F.Cu Clear resist UV resin F.Paste Create solder paste stencil + F.Silkscreen Expose UV Resin for PCB silkscreen + B.Silkscreen Burn into board the PCB silkscreen +* F.Mask Clear mask resin from PCB pads User8 Clear mask resin from PCB edge User9 PCB Shape, Cutout PCB ** PTH-drl PCB Through-Holes (Gerber & Excellon) + Optional * Mirrored in FlatCam ** If PCB not vertical line symmetric, make mirrored copy in FlatCam @@@@@ Double Sided PCB @@@@@ F.Cu Clear resist UV resin B.Cu Clear resist UV resin * F.Paste Create solder paste stencil + F.Silkscreen Expose UV Resin for PCB silkscreen + B.Silkscreen Expose UV Resin for PCB silkscreen +* F.Mask Clear mask resin from PCB pads B.Mask Clear mask resin from PCB pads * User8 Clear mask resin from PCB edge ** User9 PCB Shape, Cutout PCB ** PTH-drl PCB Through-Holes (Gerber & Excellon) ++ + Optional ++ Make mirrored copy in FlatCam * Mirrored in FlatCam ** If PCB not vertical line symmetric, make mirrored copy in FlatCam @@@@@ Creating Output Files in KiCad @@@@@ - Select Menu > File > Fabrication Outputs > Gerbers(.gbr)... - Plot format = "Gerber" - Select above layers - [Plot] - [Generate Drill Files...] - Drill File Format = Excellon - [Generate Drill Files] - Drill File Format = Gerber X2 - [Generate Drill Files]

============= [ FlatCAM 8.994 File Preparation Information ] ============= Note: Offset adjustment and PCB tiling is possible within FlatCAM, but is not covered here. *** Laser Remove Mask Resin for Etching Design *** - File > Open > Open Gerber... > Select "??-F_Cu.gbr" & "??-PTH-drl.gbr" > [Open] - Subtract Tool (ALT+W) (Use to remove pad holes) - Delete source = YES, Target = "??-F_Cu.gbr", Subtractor = "??-PTH-drl.gbr" - [Subtract Gerber] - Double-Click "??-F_Cu.gbr_sub" - [Gerber Editor] (Use for cleanup & etch compensation) - Inspect carefully for any defects or hidden unrequired track pieces - Select and delete any leftover track pieces (or fix in KiCad & Reload) - Select all remaining elements - Click [B] icon in toolbar - Buffer distance 0.022 - [B Buffer] - [Exit Editor] > [Yes] - [Isolating Routing] - Tool Table 0.075, Tool Dia 0.075, Passes 19, Overlap 33.3333% (Increase "Passes" to fit design) - [Generate Geometry] - Check Geometry has all tracks properly isolated. Modify KiCad design to resolve any issues. - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, Tool Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 5000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Expose Fast Mask Resin for PCB Front Side Silkscreen *** - File > Open > Open Gerber... > Select "??-F_Silkscreen.gbr" > [Open] - Double-Click "??-F_Silkscreen.gbr" - [Isolating Routing] (Use to generate outline use with paint tool) - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - [Paint Tool] - Tool Table 0.1, Tool Dia 0.1, Overlap 0%, Offset 0.01, Method = "Standard", Connect = NO Contour = NO - [Generate Geometry] - Click [Project] Tab - Double-Click "??-F_Silkscreen.gbr_iso_combined_mt_paint" - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.1, V-Tip Dia 0.1, V-Tip Angle 1, Feedrate XY 200, Laser Power 650 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Remove Mask Resin from Pads *** AIR ASSIST REQUIRED *** - File > Open > Open Gerber... > Select "??-F_Mask.gbr" & "??-PTH-drl.gbr" > [Open] - Subtract Tool (ALT+W) (Use to remove pad holes) - Delete source = YES, Target = "??-F_Mask.gbr", Subtractor = "??-PTH-drl.gbr" - [Subtract Gerber] - Double-Click "??-F_Mask.gbr_sub" - [Isolating Routing] (Use to generate outline use with paint tool) - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - [Paint Tool] - Tool Table 0.075, Tool Dia 0.075, Overlap 33%, Offset 0.0128, Method = "Lines", Connect = NO Contour = Yes - [Generate Geometry] - Click [Project] Tab - Double-Click "??-F_Mask.gbr_sub_iso_combined_mt_paint" - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, V-Tip Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 4400 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Remove Mask Resin from PCB EDGES *** - File > Open > Open Gerber... > Select "??-User_8.gbr" > [Open] - Double-Click "??-User_8.gbr" - [Isolating Routing] (Use to generate outline use with paint tool) - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - [Paint Tool] - Tool Table 0.075, Tool Dia 0.075, Overlap 33%, Offset 0.038, Method = "Standard", Connect = Yes Contour = Yes - [Generate Geometry] - Click [Project] Tab - Double-Click "??-User_8.gbr_iso_combined_mt_paint" - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, V-Tip Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 2000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Cut Front Side of PCB *** NOTE: Symmetrical PCB's can use the same G-Code file for both the front and back - File > Open > Open Gerber... > Select "??-User_9.gbr" > [Open] - Double-Click "??-User_9.gbr" - [Isolating Routing] - Tool Table 0.1, Tool Dia 0.1, Passes 22, Overlap 99.9999% - [Generate Geometry] - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.1, V-Tip Dia 0.1, V-Tip Angle 1, Feedrate XY 650, Laser Power 10000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Drill Alignment Holes *** - Right-Click "??-User_9.gbr" > Enable Plot - Tool > 2-Sided PCB (ALT+D) - Select "??-User_9.gbr" - [Calculate Bound Values] (if does not generate values, then disable then enable plot, and try again) - PCB Alignment: Drill Dia 1.000, Axis = Y - Click the desired location of the lower-left hole and press [+Add] (manually modify value if needed) - Click the desired location of the upper-left hole and press [+Add] (manually modify value if needed) - [Create Excellon Object] - Click [Project] Tab - Double-Click "Alignment Drills" - [Drilling Tool] - CutZ -1.9, TravelZ 1.5, FeedZ 300, Spindle 10000 - ToolChange = NO, EndMove Z 25, EndMoveXY "0,0", PreProcessor = "GRBL_11_no_M6" - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) *** Drill Pad Holes *** - File > Open > Open Excellon... > Select "??-PTH.drl" > [Open] - Double-Click "??-PTH.drl" - [Drilling Tool] - CutZ -1.9, TravelZ 1.5, FeedZ 300, Spindle 10000 - ToolChange = YES @25, EndMove Z 25, EndMoveXY "0,0", PreProcessor = "GRBL_11_no_M6" - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) *** Laser Burn Alignment Marks *** - Click "Alignment Drills" (don't enable plot!) - Edit > Conversion > Convert Any to Gerber - Double-Click "Alignment Drills_conv" - [Gerber Editor] (Use to modify mark size) - Change Aperture Size from 1.0 to 0.8 - [Exit Editor] > [Yes] - [Isolation Routing] - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, Tool Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 3000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (saftey step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Burn for PCB Back Side Silkscreen *** - File > Open > Open Gerber... > Select "??-B_Silkscreen.gbr" > [Open] - Right-Click "??-User_9.gbr" > Enable Plot - Tool > 2-Sided PCB (ALT+D) - Select "??-User_9.gbr" - [Calculate Bound Values] (if does not generate values, then disable then enable plot, and try again) - Select "??-B_Silkscreen.gbr" - Mirror Operation: Axis = Y - [Mirror] - Click [Project] Tab - Double-Click "??-B_Silkscreen.gbr" - [Isolating Routing] (Use to generate outline use with paint tool) - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - [Paint Tool] - Tool Table 0.075, Tool Dia 0.075, Overlap 20%, Offset 0.00, Method = "Standard", Connect = NO Contour = Yes - [Generate Geometry] - Click [Project] Tab - Double-Click "??-B_Silkscreen.gbr_iso_combined_mt_paint" - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, V-Tip Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 6000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT

*** Laser Cut Back Side of PCB *** NOTE: Symmetrical PCB's can use the same G-Code file for both the front and back - File > Open > Open Gerber... > Select "??-User_9.gbr" > [Open] (Opens second instance) - Right-Click "??-User_9.gbr" > Enable Plot - Tool > 2-Sided PCB (ALT+D) - Select "??-User_9.gbr" - [Calculate Bound Values] (if does not generate values, then disable then enable plot, and try again) - Select "??-User_9.gbr_1" - Mirror Operation: Axis = Y - [Mirror] - Click [Project] Tab - Double-Click "??-User_9.gbr_1" - [Isolating Routing] - Tool Table 0.1, Tool Dia 0.1, Passes 22, Overlap 99.9999% - [Generate Geometry] - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.1, V-Tip Dia 0.1, V-Tip Angle 1, Feedrate XY 650, Laser Power 10000 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT *** Laser Cut Solder Paste Stencil *** - File > Open > Open Gerber... > Select "??-F_Paste.gbr" > [Open] - Double-Click "??-F_Paste.gbr" - [Gerber Editor] (Use for burn compensation) - Select all elements - Click [B] icon in toolbar - Buffer distance -0.04 - [B Buffer] - [Exit Editor] > [Yes] - Click [Project] Tab - Double-Click "??-F_Paste.gbr_edit" - [Isolating Routing] - Tool Table 0.0001, Tool Dia 0.0001, Passes 1, Overlap 0% - [Generate Geometry] - Preprocessor = "GRBL_Laser" (!!CHOOSE FIRST!!) - Tool Table 0.075, Tool Dia 0.075, V-Tip Angle 1, Feedrate XY 650, Laser Power 3900 - [Generate CNC Job Object] - [Save CNC Code] > [Save] - Click [Project] Tab > CTRL+A > Right-Click any item > Disable Plot (clears plot area > wait till complete) - CTRL+S or File>Save>Save Project... (safety step in case of crash) - MODIFY G-CODE AS PER INFO AT BOTTOM OF THIS DOCUMENT ##################################################################### ##### ##### ##### REPLACE TEXT FOR FLATCAM GENERATED G-CODE LASER FILES ##### ##### ##### ##################################################################### *** Replace all matches with nothing as follows *** ------------ G01 F60.00 G01 F650.00 (Check this F value and replace as need be) *** Replace remaining header with below *** ------------- G21 (Millimetere units mode) G90 (Absolute distance mode) G17 (Select normal XY Plane) G94 (Feedrate as units per minute mode) $32=1 (Enable laser mode - just in case!) M5 (Stop spindle/laser) G0 F1100 (Set the rapids speed to be fast) G0 Z7.0000 (Lift Z a bit) G0 X0.0000 Y0.0000 (Send X-Y to home) G0 Z0.0000 (Send Z to home) M0 (Wait user confirmation) G00 x?? y?? <----- leave as original from here! M03 S??00.0 <----- leave as original from here! -------------

Thanks for the question! I have actually thought about it, but I have never tried it, as it would be extremely hard to cut the fine details I need using a vinyl sticker. Currently I am etching features as small as 0.1mm with spacing of 0.12mm using UV resin, my experience tells me that that would be impossible using a vinyl sticker. Thanks for all the comments and I am happy to hear you liked the videos, there will a new video out soon.

The simple answer is YES, I have had a lot of trouble clearing the pads. In my earlier episodes of the PCB series, I show a method where I use metal polish and a toothbrush to bring the pads to a shine. Even so, this method is not perfect, and I still had various problems with the whole pad clearing issue. But I have some good news, I have finally perfected this method, so your question is timed well. I am currently editing a video, which I will release in a week or so, that will revisit the entire PCB process, which includes a perfected method to clear the pads. I hope you and your fellow electronic students will find it useful!

Thanks for the comment, I’ll keep the bearing grease packing method in mind. The spindle could be running at speeds of up to 17K rpm with the right power supply, so I am not sure if having all the addition surface contact area and extra spinning mass of the rollers would be better than ball bearings. For sure they would hold up better under heavy drilling loads, but nothing like that will happen with my little CNC. But I don’t have any mechanical engineering qualifications or anything, and I am mostly guessing with this stuff, so I could be wrong!

I am glad you like the video. The purpose of the videos is only to teach, so people who are interested can learn to write code for themselves, not providing the code is my teaching method. I know there are many channels out there who will just provide code to use, so everyone can still be satisfied, depending on what they are looking for! Good luck with your channel, and thanks for taking the time to comment.

Thanks for the comment and question. But I am sorry, I really don't remember, I bought them well over 20 years ago?!?! 😬