Re: Proxxon TBM115 on it's way
Received from Harvey White at 3/5/2019 01:13 AM UTC: When you do the etching, you'll want a bubbler of some sort. The HCL/H2O2 etchant works very well until you run out of H2O2, perhaps 30 days. Use the same bubbler you use to agitate the solution when etching to rejuvenate the solution when it gets to the point that it is no longer a nice emerald green. It will turn emerald green after a number of etchings due to dissolved copper. It's starting to become spent when it starts turning brownish. That's the time to bubble air thru it 24/7 until it's emerald green again. When you find you can't rejuvenate it by bubbling air thru it, add a bit of HCl. No need to add H2O2 if you rejuvenate by bubbling air thru it... which has the advantage of not diluting the solution since drugstore H2O2 is about 94 - 97% water. Rejuvenating by bubbling isn't a fast process, but you'll have to etch a heck of a lot of boards to fall behind. Make note of the liquid level before an extended bubbling session and dilute it back up to replace evaporated water if you see that the level has dropped. Jim H
|
Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 17:39:37 -0600, you wrote: Harvey,
? Yes, all good info. My Proxxon just arrived so I will been opening
the little box and see what I bought. :)? I figure 8500 rpms will be
fine and being it's a hobby I will be ok. I have a large milling machine
and learned a lot from using it. Too bad it isn't CNC. :) One of these days, I'll complete the CNC conversion on my X1... Harvey
On 3/4/2019 1:31 PM, Harvey White wrote:
On Mon, 4 Mar 2019 12:13:29 -0600, you wrote:
Jim,
? I figured somebody was going to say that. :) I researched the other
Proxxon setup with the high speed tool but didn't want to go that route
for some reason. And I read some good reviews about the TBM 115 where
people use if for PCB's like here:
So I think I will be alright. If not, I could build my own little drill
press and get the high speed motor but I have too many things going on
right now. You'll find, that just as in machining, the RPM of the press needs to
be matched to the size of the drill.
Slower is used (at least in part) for larger holes. The largest hole
I've drilled with a carbide drill is .125 inches.
The rake on the bit is not as sharp as you might like, and there's
sufficient torque that if you don't have the board held down, it can
grab and it will wobble in your hands. That give you (at the best) an
oblong hole.
For smaller holes, around .060 or smaller, you can hand hold the board
without a clamp if the board is large enough. That's one reason that
the drills are cut the way they are, the intended use is to have a
high stability CNC head moving over a very well clamped in place
board.
The effect of runout is to make a hole oblong for larger drills. For
smaller drills, you get the same (with worse results) until the stress
breaks the bit.
So for a drill press, you want very little runout, a good way to clamp
the board for larger holes (you'll get the idea of how much on a
practice board), a good way of making sure that the drill is centered
on the pad (critical the smaller the pad is), and the highest speed
you can do (makes the hole go faster, because you have *no* idea of
how much force you put on the drill when you use a drill press. The
faster the drill speed, the quicker it can cut and the less likelyhood
you will have to break the bit through excessive pressure. You'll get
the idea after a few trials.
(yes, I did fix the problems, but it involved some significant
machining and some programming, and I ended up using a linear bearing
set to align the drill bit, and it was upside down, too).
I've seen a pneumatic PC board drill, drills from the bottom,
magnified image projected onto a glass screen. Of course, nobody
could afford it, either.
Harvey
Thanks
On 3/4/2019 11:57 AM, Jim Higgins wrote:
Received from Dave at 3/3/2019 02:41 PM UTC:
I bought a new Proxxon TBM115. The Proxxon TBM115 has a max spindle rpm of 8,500. Conventional wisdom
is to use an rpm at least 3X or 4X as fast as that to reduce the
chance of breaking a lot of bits. At 8,500 rpm your feed rate will
have to be extremely slow to avoid breaking a lot of bits... perhaps
slower than you can achieve consistently with the Proxxon TBM115.
Jim H
|
Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 16:46:21 -0600, you wrote: Harvey,
? I am a very careful person but I do appreciate the warnings
nonetheless. How thick is the correct amount of plating? Not very, I think it works out to (and check the MG chemicals website) 5 microinches/minute. I remember leaving the boards in for about 5-6 minutes, which is what they recommend. I used old photo trays, 5x7 or 8x10 were fine, and the plastic was not attacked by the chemicals. You'll want a dedicated funnel for the bottle, too. While the solution has "brighteners" in it, that remove airborne induced oxidation, the cleaner you get often the better. When I did double sided boards, I could not have any vias under a part (except a dip socket), but had to place them outside of any part. I used #26 wire to "lace" the top to the bottom at the vias, soldered both sides, then carefully clipped the excess off. I also made the top and bottom separate, and aligned them (it can get tricky) and used 30 minute (not 5, think about it....) epoxy to put the boards together, and fairly stiff pins to align them. I had masking tape on both copper sides (keeps epoxy fingerprints off...), used gloves, and used tape to hold the boards in alignment before I put the sides together. Putting it between two slabs of marble (home discount store cheap stuff), made the whole board turn out flat. Once done, remove the tape, trim to size (I use a shear), and then drill. Better to use a vacuum cleaner sucking in the debris than blowing fiberglass dust into the air. If you can find someone with a CPAP unit, the old hoses can be useful. Harvey
On 3/4/2019 3:25 PM, Harvey White wrote:
On Mon, 4 Mar 2019 13:38:34 -0600, you wrote:
Please read the warning labels, do this outside, and do not breathe
the fumes.
Time in bath equates to thickness of plating.
Solution can be reused many times until it fails.
Harvey
|
Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 16:43:20 -0600, you wrote: Ok on the top/bottom posting. Nobody is complaining yet. :)
My default trace setting was 15 and I had bumped it up to 20 so that
sounds good to me. I have seen those "islands" you speak of and figured
it was either a ground plane or a way to save etching time. I may
experiment with that. The island approach really didn't require etching, it needed an xacto knife and a ruler. Etching time will be the same, as long as you have enough etchant. Think about that one, you have to go through the same amount of copper regardless. When you do the etching, you'll want a bubbler of some sort. The HCL/H2O2 etchant works very well until you run out of H2O2, perhaps 30 days. The etchant then changes (slowly) into CuCl etchant, which etchs when oxygen is added, literally, your first time look at the copper and you'll see it turning reddish and going away, that's the copper oxidizing in solution. Once the etchant changes color, then you're likely in CuCl etching. I'm not the expert, but an internet search may give you accurate (and better than mine) details. For the mechanical approach, you could also use CNC and some sort of router bit (usually PCB and carbide). It works very well on discrete transistors/resistors/capacitors but has a limited utility when dealing with ICs... Has more to do with pin spacing than not. Main thing is that you make boards that work for you. As you decide to go from through hole to surface mount, and then to TFQP flatpacks, and then plated through holes, your techniques will change until you likely need to use a board house to make the designs. Mine did. However, there's a lot you can learn in the process. Harvey
I am using DesignSparkPCB for now.
I ordered the 16oz bottle of MG Liquid Tin. That should last me forever.
Good reasoning on why a lot of people don't use Tinit or Liquid Tin
because they finish soldering all the components right away. Now I can
plan ahead and etch, tin, and save for later finishing if need be.
Thanks
On 3/4/2019 1:45 PM, Harvey White wrote:
On Mon, 4 Mar 2019 11:31:38 -0600, you wrote:
Quick question. Is top posting preferred here. That is the way I like to
do it but on some other forums people complain and like it the other way. I prefer to interleave where reasonable. For this post, I will. For
the previous post, it was so long that without seriously trimming it,
my reply would be at the very bottom.
You get your choice, I think.
Now back to the subject at hand...All good info but, if I am just
starting out and am not worried about trace widths, my job should be
easier if I use wide traces at first, right? I remember taking apart old
electronics and the traces and solder were absolutely thick. And for
starters my projects will be very simple, like a breakout board.
Generally about 16 mils is what I normally use. However, as long as
the traces work for you, and you can build the board, it doesn't
matter.
There's a method that makes the pads as large as possible, so you're
wiring parts between very large pads, islands, even. The 1/16 inch or
so is the space around the pads. Saves etchant and can be done with
an xacto knife in some cases.
I think I seen where Rob found that Krylon enamel paint was a great
resist that could be thinned with lacquer thinner and used in a pen. Depends on how you do the board. I generally did a program (like
EAGLE), toner transfer, and then I tinned the board.
Does Tinit help any or is that just a corrosion preventative and does
anyone use it anymore? It's a bit of a corrosion inhibitor, and is effectively solder, so it
makes soldering easier.
I've done boards both ways, and if you build the board all at once,
then you likely can get away without the tin/lead. What happens if
you don't is that you get tarnish from normal oxidation and soldering
becomes difficult.
If you could mask the pads somehow, you could do a solder mask with
paing, and that would allow you to have a neater board. That, with a
silk screen layer would be a good look.
What they do in the factory is use a solder mask chemical that's UV
cureable... The stencil has holes where the pads are, you coat the
entire board with the mask, let it dry, and then the UV through the
stencil destroys the polymer so that the exposed areas wash off,
uncovering the pads.
Hence the tinning that tends to make the board look good and reduces
corrosion.
Harvey
|
Re: Proxxon TBM115 on it's way
Harvey,
? Yes, all good info. My Proxxon just arrived so I will been opening the little box and see what I bought. :)? I figure 8500 rpms will be fine and being it's a hobby I will be ok. I have a large milling machine and learned a lot from using it. Too bad it isn't CNC. :)
toggle quoted message
Show quoted text
On 3/4/2019 1:31 PM, Harvey White wrote: On Mon, 4 Mar 2019 12:13:29 -0600, you wrote:
Jim,
? I figured somebody was going to say that. :) I researched the other
Proxxon setup with the high speed tool but didn't want to go that route
for some reason. And I read some good reviews about the TBM 115 where
people use if for PCB's like here:
So I think I will be alright. If not, I could build my own little drill
press and get the high speed motor but I have too many things going on
right now. You'll find, that just as in machining, the RPM of the press needs to
be matched to the size of the drill.
Slower is used (at least in part) for larger holes. The largest hole
I've drilled with a carbide drill is .125 inches.
The rake on the bit is not as sharp as you might like, and there's
sufficient torque that if you don't have the board held down, it can
grab and it will wobble in your hands. That give you (at the best) an
oblong hole.
For smaller holes, around .060 or smaller, you can hand hold the board
without a clamp if the board is large enough. That's one reason that
the drills are cut the way they are, the intended use is to have a
high stability CNC head moving over a very well clamped in place
board.
The effect of runout is to make a hole oblong for larger drills. For
smaller drills, you get the same (with worse results) until the stress
breaks the bit.
So for a drill press, you want very little runout, a good way to clamp
the board for larger holes (you'll get the idea of how much on a
practice board), a good way of making sure that the drill is centered
on the pad (critical the smaller the pad is), and the highest speed
you can do (makes the hole go faster, because you have *no* idea of
how much force you put on the drill when you use a drill press. The
faster the drill speed, the quicker it can cut and the less likelyhood
you will have to break the bit through excessive pressure. You'll get
the idea after a few trials.
(yes, I did fix the problems, but it involved some significant
machining and some programming, and I ended up using a linear bearing
set to align the drill bit, and it was upside down, too).
I've seen a pneumatic PC board drill, drills from the bottom,
magnified image projected onto a glass screen. Of course, nobody
could afford it, either.
Harvey
Thanks
On 3/4/2019 11:57 AM, Jim Higgins wrote:
Received from Dave at 3/3/2019 02:41 PM UTC:
I bought a new Proxxon TBM115. The Proxxon TBM115 has a max spindle rpm of 8,500. Conventional wisdom
is to use an rpm at least 3X or 4X as fast as that to reduce the
chance of breaking a lot of bits. At 8,500 rpm your feed rate will
have to be extremely slow to avoid breaking a lot of bits... perhaps
slower than you can achieve consistently with the Proxxon TBM115.
Jim H
|
Re: Proxxon TBM115 on it's way
That's right. I was reading your website about the markers. I will have to use my EBucks that should be here soon from all my ebay spending the last 3 months. I remember looking for those markers and from what I remember they are not available in the US? Ok, so I will skip the sharpies after I try it and see if I get hosed too. :) And I will forget about the enamel paint too.
Thanks
toggle quoted message
Show quoted text
On 3/4/2019 1:53 PM, Rob via Groups.Io wrote: I had trouble with SHARPIE.
and industrial SHARPIE
where it would draw a little bit of black ink and that ink would wet the toner and dissovle the toner and the some toner would stick to the SHARPIE felt tip and then
block ink flow and then just simply push toner off the copper.
That sucked.
More than once.
SO
I followed advice from others here saying throwaway the SHARPIE and use EDDING 404?? and
Staedtler Lumocolor Permanent Markers and I bought a few boxes of those markers and got great results
and never will use a SHARPIE again.
My experimenting with various permanent markers over a 6 month period yielded consistent results.
Every time I would print a circuit I would add a few words or lines or protopads with a dollar store permanent marker
or nail polish or enamel paint.
There was just no comparison.
I consistently etched and watched artwork just disappear.
For my circuits with massive 1/4 inch traces I didn't care if some copper etched off where there was artwork
BUT
if that blank spot happened on a finer line or smaller pad then that would be a disaster.
so
you should grab a bunch makers and figure out what works for you and your chemistry.
Noting that my chemistry is 1 shot of muriatic acid into 2 shots of hydrogen peroxide.
I say shots ... but you could say 50 ml into 100 ml.
Same thing.
My experimenting with KRYLON enamel paint was strictly academic.
I wanted to iron out WHAT EXACTLY could be used instead of just hearing guys say they have used nail polish.
I got wrinkles ...like leaf veins.... when I tried nail polish.
So I figured nail polish was supposed to be enamel paint.....
so
I went straight to enamel paint.
My thinning and ink pen experimenting ws because I was a draftsman and I had India ink pens and knew how to
use them and then immediately wash them with a sonic cleaner
so
IF
I ever don't have a laser printer I thought it would be good to learn how to use the precision drafting pens
that could draw SOIC leads with no errors.
Now back to the subject at hand...All good info but, if I am just starting out and am not worried about trace widths, my job should be easier if I use wide traces at first, right? I remember taking apart old electronics and the traces and solder were absolutely thick. And for starters my projects will be very simple, like a breakout board.
I think I seen where Rob found that Krylon enamel paint was a great resist that could be thinned with lacquer thinner and used in a pen. Does Tinit help any or is that just a corrosion preventative and does anyone use it anymore?
Thanks
On 3/4/2019 10:55 AM, Harvey White wrote:
On Mon, 4 Mar 2019 08:52:31 -0600, you wrote:
If you look at the TRF film, you should see completely opaque areas,
and completely transparent areas.? Any transparent area with speckles
indicates that the film was trying to fill too big a gap.
The only problem with the sharpies is that they either have too large
a tip (and the smaller tips can damage the toner), or they don't put
down enough liquid, and only seal parts.
Depending on how fine the lines are, you can have to go over your
repairs to repair them.
Oh, and the only color that seems to work well is black.
You might want to try the "indelible, permanent, industrial grade" of
sharpie, there does seem to be a difference.
Harvey
On 3/3/2019 8:27 PM, Rob via Groups.Io wrote:
Using the EBAY yellow toner transfer paper
I tried the cheap EBAY TRF :
and just for the fun of it bought the shiny metallic gold TRF
for the grandchildren projects on paper.
more detailed etch process:
Noting that I would rather manually trace ALL of the toner traces with
a felt tip permanent marker
because that way I KNOW if there are any big missing pads or traces.
Pressing TRF will
NOT fix those spots.
Pressing TRF will
fix the porous nature of the toner.
My PRE toner press board preparation consists of sanding with a fine
grit sand paper then washing with pure acetone.
I have gotten very consistent results again and again and again but
once in a while I get a particularly gruesome toner transfer.
with considerably more missing toner spots.
I don't freak out... I know I just run over the traces with a
permanent marker and clean it up.
Good info Rob. The sharpie is our friend. So you are not a fan of the
TRF then I see. I guess if you have thick toner and it all transfers
perfectly then you should be done. But on finer traces etc the TRF may
help, but use a Sharpie for insurance.
|
Re: Proxxon TBM115 on it's way
Harvey,
? I am a very careful person but I do appreciate the warnings nonetheless. How thick is the correct amount of plating?
toggle quoted message
Show quoted text
On 3/4/2019 3:25 PM, Harvey White wrote: On Mon, 4 Mar 2019 13:38:34 -0600, you wrote:
Please read the warning labels, do this outside, and do not breathe
the fumes.
Time in bath equates to thickness of plating.
Solution can be reused many times until it fails.
Harvey
|
Re: Proxxon TBM115 on it's way
Ok on the top/bottom posting. Nobody is complaining yet. :)
My default trace setting was 15 and I had bumped it up to 20 so that sounds good to me. I have seen those "islands" you speak of and figured it was either a ground plane or a way to save etching time. I may experiment with that.
I am using DesignSparkPCB for now.
I ordered the 16oz bottle of MG Liquid Tin. That should last me forever. Good reasoning on why a lot of people don't use Tinit or Liquid Tin because they finish soldering all the components right away. Now I can plan ahead and etch, tin, and save for later finishing if need be.
Thanks
toggle quoted message
Show quoted text
On 3/4/2019 1:45 PM, Harvey White wrote: On Mon, 4 Mar 2019 11:31:38 -0600, you wrote:
Quick question. Is top posting preferred here. That is the way I like to
do it but on some other forums people complain and like it the other way. I prefer to interleave where reasonable. For this post, I will. For
the previous post, it was so long that without seriously trimming it,
my reply would be at the very bottom.
You get your choice, I think.
Now back to the subject at hand...All good info but, if I am just
starting out and am not worried about trace widths, my job should be
easier if I use wide traces at first, right? I remember taking apart old
electronics and the traces and solder were absolutely thick. And for
starters my projects will be very simple, like a breakout board.
Generally about 16 mils is what I normally use. However, as long as
the traces work for you, and you can build the board, it doesn't
matter.
There's a method that makes the pads as large as possible, so you're
wiring parts between very large pads, islands, even. The 1/16 inch or
so is the space around the pads. Saves etchant and can be done with
an xacto knife in some cases.
I think I seen where Rob found that Krylon enamel paint was a great
resist that could be thinned with lacquer thinner and used in a pen. Depends on how you do the board. I generally did a program (like
EAGLE), toner transfer, and then I tinned the board.
Does Tinit help any or is that just a corrosion preventative and does
anyone use it anymore? It's a bit of a corrosion inhibitor, and is effectively solder, so it
makes soldering easier.
I've done boards both ways, and if you build the board all at once,
then you likely can get away without the tin/lead. What happens if
you don't is that you get tarnish from normal oxidation and soldering
becomes difficult.
If you could mask the pads somehow, you could do a solder mask with
paing, and that would allow you to have a neater board. That, with a
silk screen layer would be a good look.
What they do in the factory is use a solder mask chemical that's UV
cureable... The stencil has holes where the pads are, you coat the
entire board with the mask, let it dry, and then the UV through the
stencil destroys the polymer so that the exposed areas wash off,
uncovering the pads.
Hence the tinning that tends to make the board look good and reduces
corrosion.
Harvey
|
Re: Proxxon TBM115 on it's way
Got it. Thanks for the clarification. Watching/waiting for the UPS man is like the old saying "a watched pot, never boils". I raked the whole front yard hoping he would show up but he will probably get here after supper. :(
toggle quoted message
Show quoted text
On 3/4/2019 3:24 PM, Harvey White wrote: On Mon, 4 Mar 2019 11:46:10 -0600, you wrote:
Ok, I see. I was a bit confused there. You are actually transferring the
backing from the foils on to the resist. Not the foil. Yep. Make the board with the toner transferred, remove paper whatever
way you do. Dry board. Put foil dull side down on board, run through
laminator (I do twice). Then I allow the board to cool and remove the
foil. Transfer that's good leaves behind clear foil carrier.
You get a layer of "foil" over the resist, sealing it.
Harvey
|
Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 13:38:34 -0600, you wrote: Please read the warning labels, do this outside, and do not breathe the fumes. Time in bath equates to thickness of plating. Solution can be reused many times until it fails. Harvey
On 3/4/2019 11:22 AM, Harvey White wrote:
On Mon, 4 Mar 2019 11:05:57 -0600, you wrote:
On 3/4/2019 9:34 AM, Kevin Byrne via Groups.Io wrote:
.
This is a link to Amazon.com exact
as to what I use, check with the group as to cheep E-Bay colors. Thanks. So does acetone remove it after you are done etching? And does
anybody use Tinit? I've found that while acetone removes the toner, it also tends to
stain the board. I've used very fine (1000 to 2000 grit) wet/dry
paper which works reasonably well. It also cleans the board for the
next step, which is using the MG chemicals tin plating solution.
Please note that this is NASTY stuff, that you want to use outside,
and not allow anywhere near food. Wash your hands afterwards, use
gloves, etc. Dedicated trays....
(and that's from reading the label).
Harvey
Harvey,
?? So the MG Chemicals must be better than Tinit I presume. I have some
Tinit on order but found a deal on the MG Chemicals stuff if I want to
try it.? I'll have to get some of that super fine sandpaper too.
Thanks
|
Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 11:46:10 -0600, you wrote: Ok, I see. I was a bit confused there. You are actually transferring the
backing from the foils on to the resist. Not the foil. Yep. Make the board with the toner transferred, remove paper whatever way you do. Dry board. Put foil dull side down on board, run through laminator (I do twice). Then I allow the board to cool and remove the foil. Transfer that's good leaves behind clear foil carrier. You get a layer of "foil" over the resist, sealing it. Harvey
On 3/4/2019 11:00 AM, Harvey White wrote:
On Mon, 4 Mar 2019 08:39:47 -0600, you wrote:
The foils sold by pulsar (they may have had a name change) are of two
varieties, white and green.
As far as I can tell, there's likely nothing special about the green,
but I'd not use metallic foils in a acid bath. The only reason to use
any other particular color would be the ease of telling where the foil
has sealed the toner.
Now on the white stuff....
Lots heavier toner, heavier to the point where you get clumps of it
sticking. You'll need to go over that with slightly tacky tape and
actually pull off the excess. I've used it only for silk screen. In
that use, a partial coverage is not as nasty as you might think.
Harvey
On 3/3/2019 7:42 PM, Harvey White wrote:
On Sun, 3 Mar 2019 15:13:46 -0600, you wrote:
On 3/3/2019 1:35 PM, Kevin Byrne via Groups.Io wrote:
Green TRF protects your traces from any and all etchant. It works real
good with Apache AL13P as that is my way. It should work with other
laminators but doesn't with household iron. Other? foil is also sold
on E-Bay. Many people use toner transfer. The basic idea is to print on paper,
then using heat transfer, get it to stick to the PC board. Toner is
plastic with graphite (more or less, it needs to be black). The fuser
in a laser printer liquifies the toner and that seeps into the paper.
The idea behind toner transfer is that you print on something where
the toner does NOT seep into the paper. Clay coated paper is one
answer. Glossy magazine paper is another. Specially coated paper
(it's detrose, like sugar, water soluable)is another.
Print on the paper. Toner adheres (however minimally) to the paper.
Invert it and put on a PC board... Run that through a laminator (or
heat source with pressure)... that melts the toner and it glues it
*AND* the paper attached to the pc board.
Now soak that in water. For most paper, the paper fibers weaken and
can be scrubbed off.... how well depend on the paper....
With the paper, the dextrose dissolves and the paper floats off.
Now the good news is that it's on the board, the bad news is that
there might be gaps and holes in the toner layer.
Green foil fills some of those blanks, and the additional material
(the green dust that adheres to the melted toner during the phase
where you heat the green foil) tends to seal the toner surface.
That is why you're using it.
Too little heat and pressure and there are gaps in the traces because
the toner doesn't stick (also if there is grease or oil on the PC
board). Lots of debate on how clean to make the board and how to
clean the board.
Too much pressure tends to flatten the traces and cause them to
spread. Generally not as much of an issue as you might think until
you start doing 100 pin chips with 0.5 mm pin spacing (and the nominal
size of the trace is 10 mils, with a 10 mil gap. best that I'd been
able to do).
Lots of variables here, so it does take some experimentation.
Harvey
Thanks Harvey for the clear and concise info on how this all works. I suppose there are "other" foils of different colors etc that do the same thing?
|
Re: Proxxon TBM115 on it's way
I had trouble with SHARPIE.
and industrial SHARPIE
where it would draw a little bit of black ink and that ink would wet the toner and dissovle the toner and the some toner would stick to the SHARPIE felt tip and then
block ink flow and then just simply push toner off the copper.
That sucked.
More than once.
SO
I followed advice from others here saying throwaway the SHARPIE and use EDDING 404?? and
Staedtler Lumocolor Permanent Markers and I bought a few boxes of those markers and got great results
and never will use a SHARPIE again.
My experimenting with various permanent markers over a 6 month period yielded consistent results.
Every time I would print a circuit I would add a few words or lines or protopads with a dollar store permanent marker
or nail polish or enamel paint.
There was just no comparison.
I consistently etched and watched artwork just disappear.
For my circuits with massive 1/4 inch traces I didn't care if some copper etched off where there was artwork
BUT
if that blank spot happened on a finer line or smaller pad then that would be a disaster.
so
you should grab a bunch makers and figure out what works for you and your chemistry.
Noting that my chemistry is 1 shot of muriatic acid into 2 shots of hydrogen peroxide.
I say shots ... but you could say 50 ml into 100 ml.
Same thing.
My experimenting with KRYLON enamel paint was strictly academic.
I wanted to iron out WHAT EXACTLY could be used instead of just hearing guys say they have used nail polish.
I got wrinkles ...like leaf veins.... when I tried nail polish.
So I figured nail polish was supposed to be enamel paint.....
so
I went straight to enamel paint.
My thinning and ink pen experimenting ws because I was a draftsman and I had India ink pens and knew how to
use them and then immediately wash them with a sonic cleaner
so
IF
I ever don't have a laser printer I thought it would be good to learn how to use the precision drafting pens
that could draw SOIC leads with no errors.
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Now back to the subject at hand...All good info but, if I am just starting out and am not worried about trace widths, my job should be easier if I use wide traces at first, right? I remember taking apart old electronics and the traces and solder were absolutely thick. And for starters my projects will be very simple, like a breakout board.
I think I seen where Rob found that Krylon enamel paint was a great resist that could be thinned with lacquer thinner and used in a pen. Does Tinit help any or is that just a corrosion preventative and does anyone use it anymore?
Thanks
On 3/4/2019 10:55 AM, Harvey White wrote:
On Mon, 4 Mar 2019 08:52:31 -0600, you wrote:
If you look at the TRF film, you should see completely opaque areas,
and completely transparent areas.? Any transparent area with speckles
indicates that the film was trying to fill too big a gap.
The only problem with the sharpies is that they either have too large
a tip (and the smaller tips can damage the toner), or they don't put
down enough liquid, and only seal parts.
Depending on how fine the lines are, you can have to go over your
repairs to repair them.
Oh, and the only color that seems to work well is black.
You might want to try the "indelible, permanent, industrial grade" of
sharpie, there does seem to be a difference.
Harvey
On 3/3/2019 8:27 PM, Rob via Groups.Io wrote:
Using the EBAY yellow toner transfer paper
I tried the cheap EBAY TRF :
and just for the fun of it bought the shiny metallic gold TRF
for the grandchildren projects on paper.
more detailed etch process:
Noting that I would rather manually trace ALL of the toner traces with
a felt tip permanent marker
because that way I KNOW if there are any big missing pads or traces.
??????????????????????????????????????????????????? Pressing TRF will
NOT fix those spots.
Pressing TRF will
fix the porous nature of the toner.
My PRE toner press board preparation consists of sanding with a fine
grit sand paper then washing with pure acetone.
I have gotten very consistent results again and again and again but
once in a while I get a particularly gruesome toner transfer.
with considerably more missing toner spots.
I don't freak out... I know I just run over the traces with a
permanent marker and clean it up.
Good info Rob. The sharpie is our friend. So you are not a fan of the
TRF then I see. I guess if you have thick toner and it all transfers
perfectly then you should be done. But on finer traces etc the TRF may
help, but use a Sharpie for insurance.
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Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 11:31:38 -0600, you wrote: Quick question. Is top posting preferred here. That is the way I like to
do it but on some other forums people complain and like it the other way. I prefer to interleave where reasonable. For this post, I will. For the previous post, it was so long that without seriously trimming it, my reply would be at the very bottom. You get your choice, I think.
Now back to the subject at hand...All good info but, if I am just
starting out and am not worried about trace widths, my job should be
easier if I use wide traces at first, right? I remember taking apart old
electronics and the traces and solder were absolutely thick. And for
starters my projects will be very simple, like a breakout board.
Generally about 16 mils is what I normally use. However, as long as the traces work for you, and you can build the board, it doesn't matter. There's a method that makes the pads as large as possible, so you're wiring parts between very large pads, islands, even. The 1/16 inch or so is the space around the pads. Saves etchant and can be done with an xacto knife in some cases. I think I seen where Rob found that Krylon enamel paint was a great
resist that could be thinned with lacquer thinner and used in a pen. Depends on how you do the board. I generally did a program (like EAGLE), toner transfer, and then I tinned the board. Does Tinit help any or is that just a corrosion preventative and does
anyone use it anymore? It's a bit of a corrosion inhibitor, and is effectively solder, so it makes soldering easier. I've done boards both ways, and if you build the board all at once, then you likely can get away without the tin/lead. What happens if you don't is that you get tarnish from normal oxidation and soldering becomes difficult. If you could mask the pads somehow, you could do a solder mask with paing, and that would allow you to have a neater board. That, with a silk screen layer would be a good look. What they do in the factory is use a solder mask chemical that's UV cureable... The stencil has holes where the pads are, you coat the entire board with the mask, let it dry, and then the UV through the stencil destroys the polymer so that the exposed areas wash off, uncovering the pads. Hence the tinning that tends to make the board look good and reduces corrosion. Harvey
Thanks
On 3/4/2019 10:55 AM, Harvey White wrote:
On Mon, 4 Mar 2019 08:52:31 -0600, you wrote:
If you look at the TRF film, you should see completely opaque areas,
and completely transparent areas. Any transparent area with speckles
indicates that the film was trying to fill too big a gap.
The only problem with the sharpies is that they either have too large
a tip (and the smaller tips can damage the toner), or they don't put
down enough liquid, and only seal parts.
Depending on how fine the lines are, you can have to go over your
repairs to repair them.
Oh, and the only color that seems to work well is black.
You might want to try the "indelible, permanent, industrial grade" of
sharpie, there does seem to be a difference.
Harvey
On 3/3/2019 8:27 PM, Rob via Groups.Io wrote:
Using the EBAY yellow toner transfer paper
I tried the cheap EBAY TRF :
and just for the fun of it bought the shiny metallic gold TRF
for the grandchildren projects on paper.
more detailed etch process:
Noting that I would rather manually trace ALL of the toner traces with
a felt tip permanent marker
because that way I KNOW if there are any big missing pads or traces.
?????????????????????????????????????????????????? Pressing TRF will
NOT fix those spots.
???????????????????????????????????????????????????? Pressing TRF will
fix the porous nature of the toner.
My PRE toner press board preparation consists of sanding with a fine
grit sand paper then washing with pure acetone.
I have gotten very consistent results again and again and again but
once in a while I get a particularly gruesome toner transfer.
with considerably more missing toner spots.
I don't freak out... I know I just run over the traces with a
permanent marker and clean it up.
Good info Rob. The sharpie is our friend. So you are not a fan of the
TRF then I see. I guess if you have thick toner and it all transfers
perfectly then you should be done. But on finer traces etc the TRF may
help, but use a Sharpie for insurance.
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Re: Proxxon TBM115 on it's way
On 3/4/2019 11:22 AM, Harvey White wrote: On Mon, 4 Mar 2019 11:05:57 -0600, you wrote:
On 3/4/2019 9:34 AM, Kevin Byrne via Groups.Io wrote:
.
This is a link to Amazon.com exact
as to what I use, check with the group as to cheep E-Bay colors. Thanks. So does acetone remove it after you are done etching? And does
anybody use Tinit? I've found that while acetone removes the toner, it also tends to
stain the board. I've used very fine (1000 to 2000 grit) wet/dry
paper which works reasonably well. It also cleans the board for the
next step, which is using the MG chemicals tin plating solution.
Please note that this is NASTY stuff, that you want to use outside,
and not allow anywhere near food. Wash your hands afterwards, use
gloves, etc. Dedicated trays....
(and that's from reading the label).
Harvey
Harvey, ?? So the MG Chemicals must be better than Tinit I presume. I have some Tinit on order but found a deal on the MG Chemicals stuff if I want to try it.? I'll have to get some of that super fine sandpaper too. Thanks
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Re: Proxxon TBM115 on it's way
On Mon, 4 Mar 2019 12:13:29 -0600, you wrote: Jim,
? I figured somebody was going to say that. :) I researched the other
Proxxon setup with the high speed tool but didn't want to go that route
for some reason. And I read some good reviews about the TBM 115 where
people use if for PCB's like here:
So I think I will be alright. If not, I could build my own little drill
press and get the high speed motor but I have too many things going on
right now. You'll find, that just as in machining, the RPM of the press needs to be matched to the size of the drill. Slower is used (at least in part) for larger holes. The largest hole I've drilled with a carbide drill is .125 inches. The rake on the bit is not as sharp as you might like, and there's sufficient torque that if you don't have the board held down, it can grab and it will wobble in your hands. That give you (at the best) an oblong hole. For smaller holes, around .060 or smaller, you can hand hold the board without a clamp if the board is large enough. That's one reason that the drills are cut the way they are, the intended use is to have a high stability CNC head moving over a very well clamped in place board. The effect of runout is to make a hole oblong for larger drills. For smaller drills, you get the same (with worse results) until the stress breaks the bit. So for a drill press, you want very little runout, a good way to clamp the board for larger holes (you'll get the idea of how much on a practice board), a good way of making sure that the drill is centered on the pad (critical the smaller the pad is), and the highest speed you can do (makes the hole go faster, because you have *no* idea of how much force you put on the drill when you use a drill press. The faster the drill speed, the quicker it can cut and the less likelyhood you will have to break the bit through excessive pressure. You'll get the idea after a few trials. (yes, I did fix the problems, but it involved some significant machining and some programming, and I ended up using a linear bearing set to align the drill bit, and it was upside down, too). I've seen a pneumatic PC board drill, drills from the bottom, magnified image projected onto a glass screen. Of course, nobody could afford it, either. Harvey
Thanks
On 3/4/2019 11:57 AM, Jim Higgins wrote:
Received from Dave at 3/3/2019 02:41 PM UTC:
I bought a new Proxxon TBM115.
The Proxxon TBM115 has a max spindle rpm of 8,500. Conventional wisdom
is to use an rpm at least 3X or 4X as fast as that to reduce the
chance of breaking a lot of bits. At 8,500 rpm your feed rate will
have to be extremely slow to avoid breaking a lot of bits... perhaps
slower than you can achieve consistently with the Proxxon TBM115.
Jim H
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Re: Proxxon TBM115 on it's way
Thanks Steve. I feel better already. Mine is out for delivery so I should have it soon. Did you have to replace the belt yet? I wonder if I should order a spare or two for future reference. I have some carbide drill bits (too small) here but more on the way. What size bits do you use the most of? Or better yet what size bits are most commonly used for thru hole pcb's? I think an aquarium pump may work but I know what you mean on the air blower. We have sewing machine oil. Once I evaluate the spindle heat I may have to mod it with a heat sink and a pc fan. But I think it will be ok as my boards will be small and not by the hundreds.? :) And I just ordered some Jumbo LED's so I can fashion something like this:
Planning to have some fun!
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On 3/4/2019 12:13 PM, Steven B wrote: I have a Proxxon TBM115? and it has served me well on drilling hundreds of PC boards at my fabrication shop.
There are definitely better drill press setups available. But prices do get high.
I would recommend buying the drill bits for PCB drilling. These are the ones with the colored collars on them that you see on ebay and amazon and so on...
Check the belt tension also, and monitor how hot the spindle area gets, the belt does not have to be super tight, my spindle gets pretty warm after a 20 or so boards of continuous drilling.
Some light synthetic oil or sewing machine oil keeps everything lubed up in the spindle area. A good light shining on the board helps a lot !!
Also, at the junk store I found a respirator pump (?) it's like a little air pump in a plastic case, blows a constant stream of air onto my drilling area to keep the area clear of dust.
The big thing is not to let the board jiggle or rise up as the bit makes contact with the board, that generally breaks the bit (in my case) as it puts a bunch of force against the side of the bit.
Have Fun !
-Steve
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Re: Proxxon TBM115 on it's way
I have a Proxxon TBM115? and it has served me well on drilling hundreds of PC boards at my fabrication shop.
There are definitely better drill press setups available. But prices do get high.
I would recommend buying the drill bits for PCB drilling. These are the ones with the colored collars on them that you see on ebay and amazon and so on...
Check the belt tension also, and monitor how hot the spindle area gets, the belt does not have to be super tight, my spindle gets pretty warm after a 20 or so boards of continuous drilling.
Some light synthetic oil or sewing machine oil keeps everything lubed up in the spindle area. A good light shining on the board helps a lot !!
Also, at the junk store I found a respirator pump (?) it's like a little air pump in a plastic case, blows a constant stream of air onto my drilling area to keep the area clear of dust.
The big thing is not to let the board jiggle or rise up as the bit makes contact with the board, that generally breaks the bit (in my case) as it puts a bunch of force against the side of the bit.
Have Fun !
-Steve
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Re: Proxxon TBM115 on it's way
Jim,
? I figured somebody was going to say that. :) I researched the other Proxxon setup with the high speed tool but didn't want to go that route for some reason. And I read some good reviews about the TBM 115 where people use if for PCB's like here:
So I think I will be alright. If not, I could build my own little drill press and get the high speed motor but I have too many things going on right now.
Thanks
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Show quoted text
On 3/4/2019 11:57 AM, Jim Higgins wrote: Received from Dave at 3/3/2019 02:41 PM UTC:
I bought a new Proxxon TBM115.
The Proxxon TBM115 has a max spindle rpm of 8,500. Conventional wisdom is to use an rpm at least 3X or 4X as fast as that to reduce the chance of breaking a lot of bits. At 8,500 rpm your feed rate will have to be extremely slow to avoid breaking a lot of bits... perhaps slower than you can achieve consistently with the Proxxon TBM115.
Jim H
|
Re: Proxxon TBM115 on it's way
Received from Dave at 3/3/2019 02:41 PM UTC: I bought a new Proxxon TBM115. The Proxxon TBM115 has a max spindle rpm of 8,500. Conventional wisdom is to use an rpm at least 3X or 4X as fast as that to reduce the chance of breaking a lot of bits. At 8,500 rpm your feed rate will have to be extremely slow to avoid breaking a lot of bits... perhaps slower than you can achieve consistently with the Proxxon TBM115. Jim H
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Re: Proxxon TBM115 on it's way
Ok, I see. I was a bit confused there. You are actually transferring the backing from the foils on to the resist. Not the foil.
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On 3/4/2019 11:00 AM, Harvey White wrote: On Mon, 4 Mar 2019 08:39:47 -0600, you wrote:
The foils sold by pulsar (they may have had a name change) are of two
varieties, white and green.
As far as I can tell, there's likely nothing special about the green,
but I'd not use metallic foils in a acid bath. The only reason to use
any other particular color would be the ease of telling where the foil
has sealed the toner.
Now on the white stuff....
Lots heavier toner, heavier to the point where you get clumps of it
sticking. You'll need to go over that with slightly tacky tape and
actually pull off the excess. I've used it only for silk screen. In
that use, a partial coverage is not as nasty as you might think.
Harvey
On 3/3/2019 7:42 PM, Harvey White wrote:
On Sun, 3 Mar 2019 15:13:46 -0600, you wrote:
On 3/3/2019 1:35 PM, Kevin Byrne via Groups.Io wrote:
Green TRF protects your traces from any and all etchant. It works real
good with Apache AL13P as that is my way. It should work with other
laminators but doesn't with household iron. Other? foil is also sold
on E-Bay. Many people use toner transfer. The basic idea is to print on paper,
then using heat transfer, get it to stick to the PC board. Toner is
plastic with graphite (more or less, it needs to be black). The fuser
in a laser printer liquifies the toner and that seeps into the paper.
The idea behind toner transfer is that you print on something where
the toner does NOT seep into the paper. Clay coated paper is one
answer. Glossy magazine paper is another. Specially coated paper
(it's detrose, like sugar, water soluable)is another.
Print on the paper. Toner adheres (however minimally) to the paper.
Invert it and put on a PC board... Run that through a laminator (or
heat source with pressure)... that melts the toner and it glues it
*AND* the paper attached to the pc board.
Now soak that in water. For most paper, the paper fibers weaken and
can be scrubbed off.... how well depend on the paper....
With the paper, the dextrose dissolves and the paper floats off.
Now the good news is that it's on the board, the bad news is that
there might be gaps and holes in the toner layer.
Green foil fills some of those blanks, and the additional material
(the green dust that adheres to the melted toner during the phase
where you heat the green foil) tends to seal the toner surface.
That is why you're using it.
Too little heat and pressure and there are gaps in the traces because
the toner doesn't stick (also if there is grease or oil on the PC
board). Lots of debate on how clean to make the board and how to
clean the board.
Too much pressure tends to flatten the traces and cause them to
spread. Generally not as much of an issue as you might think until
you start doing 100 pin chips with 0.5 mm pin spacing (and the nominal
size of the trace is 10 mils, with a 10 mil gap. best that I'd been
able to do).
Lots of variables here, so it does take some experimentation.
Harvey
Thanks Harvey for the clear and concise info on how this all works. I suppose there are "other" foils of different colors etc that do the same thing?
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