Printed circuit board fabrication
 

You people have given me great advice before (grovel, grovel) so here I am
asking for some more.

I've made PCBs before but always as one-off projects using transfers and
etch resist pens. But I need to produce 50-60 now !

My requirements are very modest...single sided, a couple of 14 pin DILs and
a few other components, size around 50mm x 100mm.

Does anybody know of a reasonably priced outfit who can supply small PCBs ?
Artwork would be supplied by me. In what form is this normally required ?

Or should I go ahead get a photoresist kit and supplies ? I'm starting from
scratch here with a few working prototypes on veroboard.

Thanks all.

Printed circuit board fabrication
 

TonyL wrote:

oes anybody know of a reasonably priced outfit who can supply small PCBs ?
Artwork would be supplied by me. In what form is this normally required ?

I think I saw on the Make website recently a service that will make them
from uploadable artwork.

Daniele

Printed circuit board fabrication
 

In article ,
TonyL wrote:
You people have given me great advice before (grovel, grovel) so here I
am asking for some more.

I've made PCBs before but always as one-off projects using transfers and
etch resist pens. But I need to produce 50-60 now !

There are very much easier ways these days - by drawing out what's needed
on a computer.

My requirements are very modest...single sided, a couple of 14 pin DILs
and a few other components, size around 50mm x 100mm.

Does anybody know of a reasonably priced outfit who can supply small
PCBs ? Artwork would be supplied by me. In what form is this normally
required ?

I think I've seen firms advertising on Ebay who do small runs. Of course
that might mean 20,000...

Or should I go ahead get a photoresist kit and supplies ? I'm starting
from scratch here with a few working prototypes on veroboard.

Have a look at RS Components site for the options on small DIY production
runs.

One way is to make a transparency and use that to mask a board coated with
an emulsion then exposed to UV and develop. Then etch in the normal way.
There's now another option - you print to a special paper and iron that on
to plain PCB. Haven't tried that one yet.

--
*If horrific means to make horrible, does terrific mean to make terrible?

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

Dave Plowman (News) wrote:
In article ,
TonyL wrote:
You people have given me great advice before (grovel, grovel) so
here I am asking for some more.

I've made PCBs before but always as one-off projects using transfers
and etch resist pens. But I need to produce 50-60 now !

There are very much easier ways these days - by drawing out what's
needed on a computer.


Yes, I've got that far. For example:
http://www.freepcb.com/


I think I've seen firms advertising on Ebay who do small runs. Of
course that might mean 20,000...


I got an estimate from a company picked more or less at random. Price wasn't
bad at 1.50 UKP per board, but "tooling up" charge was nearly 100 UKP.
Actually less than I expected but I also need a smaller (around 10-20)
quantity of boards with a different layout which means £200 initial outlay.

Or should I go ahead get a photoresist kit and supplies ? I'm
starting from scratch here with a few working prototypes on
veroboard.

Have a look at RS Components site for the options on small DIY
production runs.


OK, thanks. Willdo.

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes with UV
bulbs and maybe a timer. Any reason I can't make my own box and buy a
replacement UV bulb or two ?

There's now another option - you print to a special paper
and iron that on to plain PCB. Haven't tried that one yet.


I assume I would have to print out a fresh one for each pcb.....OTOH they
could be done as in multiple boards per sheet and seperated after the
etching is done...hmm...

Thanks for the ideas.

Printed circuit board fabrication
 

D.M. Procida wrote:
TonyL wrote:

oes anybody know of a reasonably priced outfit who can supply small
PCBs ? Artwork would be supplied by me. In what form is this
normally required ?

I think I saw on the Make website recently a service that will make
them from uploadable artwork.

Daniele


Thanks, have you got the URL ? I Googled on "make pcb uk" and nothing
relevant listed.

Printed circuit board fabrication
 

TonyL wrote:

I think I saw on the Make website recently a service that will make
them from uploadable artwork.

Thanks, have you got the URL ? I Googled on "make pcb uk" and nothing
relevant listed.

I can't find it either, sorry. I am pretty sure it was a UK service. Try
asking on uk.d-i.y.

Daniele

Printed circuit board fabrication
 

Its the bloody holes that cause the hassle usually.
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Dave Plowman (News)" wrote in message
...
In article ,
TonyL wrote:
You people have given me great advice before (grovel, grovel) so here I
am asking for some more.

I've made PCBs before but always as one-off projects using transfers and
etch resist pens. But I need to produce 50-60 now !

There are very much easier ways these days - by drawing out what's needed
on a computer.

My requirements are very modest...single sided, a couple of 14 pin DILs
and a few other components, size around 50mm x 100mm.

Does anybody know of a reasonably priced outfit who can supply small
PCBs ? Artwork would be supplied by me. In what form is this normally
required ?

I think I've seen firms advertising on Ebay who do small runs. Of course
that might mean 20,000...

Or should I go ahead get a photoresist kit and supplies ? I'm starting
from scratch here with a few working prototypes on veroboard.

Have a look at RS Components site for the options on small DIY production
runs.

One way is to make a transparency and use that to mask a board coated with
an emulsion then exposed to UV and develop. Then etch in the normal way.
There's now another option - you print to a special paper and iron that on
to plain PCB. Haven't tried that one yet.

--
*If horrific means to make horrible, does terrific mean to make terrible?

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

When you say you need two different ones, are they totally different, or
could you have both simply by having a few links on the pcb? That way, only
one tooling up cost.
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"TonyL" wrote in message
...
Dave Plowman (News) wrote:
In article ,
TonyL wrote:
You people have given me great advice before (grovel, grovel) so
here I am asking for some more.

I've made PCBs before but always as one-off projects using transfers
and etch resist pens. But I need to produce 50-60 now !

There are very much easier ways these days - by drawing out what's
needed on a computer.


Yes, I've got that far. For example:
http://www.freepcb.com/


I think I've seen firms advertising on Ebay who do small runs. Of
course that might mean 20,000...


I got an estimate from a company picked more or less at random. Price
wasn't bad at 1.50 UKP per board, but "tooling up" charge was nearly 100
UKP. Actually less than I expected but I also need a smaller (around
10-20) quantity of boards with a different layout which means £200
initial outlay.

Or should I go ahead get a photoresist kit and supplies ? I'm
starting from scratch here with a few working prototypes on
veroboard.

Have a look at RS Components site for the options on small DIY
production runs.


OK, thanks. Willdo.

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy a
replacement UV bulb or two ?

There's now another option - you print to a special paper
and iron that on to plain PCB. Haven't tried that one yet.


I assume I would have to print out a fresh one for each pcb.....OTOH they
could be done as in multiple boards per sheet and seperated after the
etching is done...hmm...

Thanks for the ideas.

Printed circuit board fabrication
 

In article ,
TonyL wrote:
One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy
a replacement UV bulb or two ?

None. Especially if you can get a couple of cheap fluorescent fittings and
get UV tubes for them.

There's now another option - you print to a special paper
and iron that on to plain PCB. Haven't tried that one yet.


I assume I would have to print out a fresh one for each pcb.....OTOH
they could be done as in multiple boards per sheet and seperated after
the etching is done...hmm...

Yes - you duplicate the layout up to the maximum number the board can take
and then cut them to size afterwards. You'd need to work out the best use
if the paper too as it's quite expensive.

Thanks for the ideas.

--
*Growing old is inevitable, growing up is optional *

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

"TonyL" wrote in message
...
You people have given me great advice before (grovel, grovel) so here I am
asking for some more.

I've made PCBs before but always as one-off projects using transfers and
etch resist pens. But I need to produce 50-60 now !

My requirements are very modest...single sided, a couple of 14 pin DILs
and a few other components, size around 50mm x 100mm.

Does anybody know of a reasonably priced outfit who can supply small PCBs
? Artwork would be supplied by me. In what form is this normally required
?

Or should I go ahead get a photoresist kit and supplies ? I'm starting
from scratch here with a few working prototypes on veroboard.


I had a PCB made up a few years back. Normally I build everything on
veroboard, but this particular job required several multi-legged surface
mount chips and there was no way I was going to be able to do that on
veroboard, nor was I going to be able to achieve anything approaching the
required accuracy with a DIY PCB. The company I found had their own PCB
design software that could be downloaded from their website. After designing
the board I uploaded the design and pretty soon afterwards the PCBs arrived
in the post. I can't at the moment remember the name of the company or how
much it cost, but it did seem good value at the time.

David.

Printed circuit board fabrication
 

Brian Gaff wrote:
Its the bloody holes that cause the hassle usually.
Brian


I have a drill press that makes clean 1 mm or less holes quite neatly. I
don't need plated through. btw.

Printed circuit board fabrication
 

Brian Gaff wrote:
When you say you need two different ones, are they totally different,
or could you have both simply by having a few links on the pcb? That
way, only one tooling up cost.

Good idea, unfortunately they are a lot different.

Printed circuit board fabrication
 

David Looser wrote:

I had a PCB made up a few years back. Normally I build everything on
veroboard,


Same here.

but this particular job required several multi-legged
surface mount chips and there was no way I was going to be able to do
that on veroboard, nor was I going to be able to achieve anything
approaching the required accuracy with a DIY PCB.

The only smd work I've done was to modify a webcam for astrophotography
work. That involved lifting a few chip legs and soldering some wires to
them. That was bad enough, thank you.


The company I found
had their own PCB design software that could be downloaded from their
website. After designing the board I uploaded the design and pretty
soon afterwards the PCBs arrived in the post. I can't at the moment
remember the name of the company or how much it cost, but it did seem
good value at the time.

If it should come to you, please let me know.

In the meantime I'll Google and Ebay when I get time.

Printed circuit board fabrication
 

"Tony Lacy Cock Sucker "

You people have given me great advice before (grovel, grovel) so here I am
asking for some more.


** Get this OT ****e of the NG

- you PITA pommy ****head !!

Printed circuit board fabrication
 

"Tony Lacy Cock Sucker "

You people have given me great advice before (grovel, grovel) so here I am
asking for some more.


** Get this OT ****e of the NG

- you PITA pommy ****head !!

Printed circuit board fabrication
 

"Tony Lacy Cock Sucker "

You people have given me great advice before (grovel, grovel) so here I am
asking for some more.


** Get this OT ****e of the NG

- you PITA pommy ****head !!

Printed circuit board fabrication
 

"TonyL"

"Tony Lacy Cock Sucker "

You people have given me great advice before (grovel, grovel) so here I am
asking for some more.


** Get this OT ****e of the NG

- you PITA pommy ****head !!

Printed circuit board fabrication
 

"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy a
replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?

Also, direct sunlight is loaded with UV.

Printed circuit board fabrication
 

Hi Tony

there is quite a good article here about making the parts for short
production runs of PCBs

http://www.electricstuff.co.uk/pcbs.html

You can also get the required parts and chemicals from he

http://www.megauk.com/

With regards to the software, there are several low-cost packages you can
buy. If you are local to Maplins (I assume that you are in the UK and not
in the colonies as one of this newsgroup's contributors is) there is a neat
little software package called PCB Wizard which costs around £30 or so and
does most functions and has some libraries, auto routing etc.

So it might cost you about £100 of so to set it up, assuming that you have a
good quality printer, but its also good fun and you will never use Veroboard
again :-)

Cheers

Mike


"TonyL" wrote in message
...
You people have given me great advice before (grovel, grovel) so here I am
asking for some more.

I've made PCBs before but always as one-off projects using transfers and
etch resist pens. But I need to produce 50-60 now !

My requirements are very modest...single sided, a couple of 14 pin DILs
and a few other components, size around 50mm x 100mm.

Does anybody know of a reasonably priced outfit who can supply small PCBs
? Artwork would be supplied by me. In what form is this normally required
?

Or should I go ahead get a photoresist kit and supplies ? I'm starting
from scratch here with a few working prototypes on veroboard.

Thanks all.

Printed circuit board fabrication
 

Arny Krueger wrote:
"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board
coated with an emulsion then exposed to UV and develop. Then etch
in the normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with UV bulbs and maybe a timer. Any reason I can't make my own box
and buy a replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?


I've never seen that. I would imagine handling while keeping it out of the
light would be inconvenient.

Also, direct sunlight is loaded with UV.


Sun ? Sun ? This is February and I'm in Wales !

Printed circuit board fabrication
 

fredbloggstwo wrote:
Hi Tony

there is quite a good article here about making the parts for short
production runs of PCBs

http://www.electricstuff.co.uk/pcbs.html

You can also get the required parts and chemicals from he

http://www.megauk.com/

With regards to the software, there are several low-cost packages you
can buy. If you are local to Maplins (I assume that you are in the
UK and not in the colonies as one of this newsgroup's contributors
is) there is a neat little software package called PCB Wizard which
costs around £30 or so and does most functions and has some
libraries, auto routing etc.
So it might cost you about £100 of so to set it up, assuming that you
have a good quality printer, but its also good fun and you will never
use Veroboard again :-)

Cheers

Mike

Thanks Mike,

Closest Maplins is in Shrewsbury, about an hour away, but Maplins online
delivery service is pretty good.

I've been looking at the open source package http://www.freepcb.com/ but it
seems too advanced for my needs. It would take me longer to enter a netlist
and learn how to use this app than simply drawing a layout in a paint
program. Maybe PCB Wizard is more user friendly. Just drag/drop from a
component pallet then drag tracks around to connect stuff. That would be
plenty for me.

Thanks for the links, great article !

Printed circuit board fabrication
 

On Fri, 6 Feb 2009 18:24:37 -0000, "TonyL"
wrote:

Arny Krueger wrote:
"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board
coated with an emulsion then exposed to UV and develop. Then etch
in the normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with UV bulbs and maybe a timer. Any reason I can't make my own box
and buy a replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?


I've never seen that. I would imagine handling while keeping it out of the
light would be inconvenient.

Radiospares used to do UV sensitive double sided board. It was covered
with black plastic, which you could use as a resist if you fancied
just cutting the pattern with a scalpel. No idea if they still stock
it.

d
--
Pearce Consulting
http://www.pearce.uk.com

Printed circuit board fabrication
 

On Fri, 06 Feb 2009 18:51:36 GMT, (Don Pearce)
wrote:

On Fri, 6 Feb 2009 18:24:37 -0000, "TonyL"
wrote:

Arny Krueger wrote:
"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board
coated with an emulsion then exposed to UV and develop. Then etch
in the normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with UV bulbs and maybe a timer. Any reason I can't make my own box
and buy a replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?


I've never seen that. I would imagine handling while keeping it out of the
light would be inconvenient.

Radiospares used to do UV sensitive double sided board. It was covered
with black plastic, which you could use as a resist if you fancied
just cutting the pattern with a scalpel. No idea if they still stock
it.


Just checked - they do.

d

Printed circuit board fabrication
 

"Don Pearce" wrote in message
...
On Fri, 6 Feb 2009 18:24:37 -0000, "TonyL"
wrote:

Arny Krueger wrote:
"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board
coated with an emulsion then exposed to UV and develop. Then etch
in the normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with UV bulbs and maybe a timer. Any reason I can't make my own box
and buy a replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?


I've never seen that. I would imagine handling while keeping it out of the
light would be inconvenient.

It wasn't all that sensitive.

Radiospares used to do UV sensitive double sided board. It was covered
with black plastic, which you could use as a resist if you fancied
just cutting the pattern with a scalpel. No idea if they still stock
it.

Seems like UV is the more modern approach. Plenty of that around as long as
the Sun is shining.

Printed circuit board fabrication
 

In article ,
Arny Krueger wrote:

"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.


That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy a
replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?

Also, direct sunlight is loaded with UV.

You do need to use a reasonably accurate combination of level and time
though - like any exposure. And the coated board is rather expensive to
experiment with.

--
*Why is it considered necessary to screw down the lid of a coffin?

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

Dave Plowman (News) wrote:

You do need to use a reasonably accurate combination of level and time
though - like any exposure. And the coated board is rather expensive
to experiment with.


I would guess for calibration....a timer and a 1 cm by 10 cm strip of coated
board with sections exposed for various time periods.

Printed circuit board fabrication
 

"TonyL" wrote in message
...
Dave Plowman (News) wrote:

You do need to use a reasonably accurate combination of level and time
though - like any exposure. And the coated board is rather expensive
to experiment with.


I would guess for calibration....a timer and a 1 cm by 10 cm strip of
coated board with sections exposed for various time periods.


Not a lot of use with sunshine, as the UV content varies from
minute-to-minute depending on cloud cover.

David.

Printed circuit board fabrication
 

In article ,
TonyL wrote:
I've been looking at the open source package http://www.freepcb.com/ but
it seems too advanced for my needs. It would take me longer to enter a
netlist and learn how to use this app than simply drawing a layout in a
paint program. Maybe PCB Wizard is more user friendly. Just drag/drop
from a component pallet then drag tracks around to connect stuff. That
would be plenty for me.

It's one reason I still use RISC OS. The Draw prog on that with a small
library of basic pad layouts is all that's needed for simple stuff. Same
for drawing circuit diagrams. But then I quite enjoy figuring out layouts
and best track routes. IMHO it takes too long to learn a CAD one to be
worth it unless you're using it frequently.

--
*Modulation in all things *

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

In article ,
TonyL wrote:
You do need to use a reasonably accurate combination of level and time
though - like any exposure. And the coated board is rather expensive
to experiment with.


I would guess for calibration....a timer and a 1 cm by 10 cm strip of
coated board with sections exposed for various time periods.

Yes - with a light box which I have. But with the sun it would vary
according to time of day and year - even on a cloudless day?

IIRC, some ovens with exposed elements can be used too.

--
*It's o.k. to laugh during sexŒ.Œ.just don't point!

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

"Dave Plowman (News)" wrote in message
...
In article ,
Arny Krueger wrote:

"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.

That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy
a
replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?

Also, direct sunlight is loaded with UV.


You do need to use a reasonably accurate combination of level and time
though - like any exposure.

Not like *any* exposure. The "negative" generally is line art, thick black
over transparent film. Very, very high contrast. The "film" is designed to
be very tolerant of small exposures to light. It wants to produce a high
contrast "picture".

And the coated board is rather expensive to experiment with.

With the old stuff, I never ever missed the first time. After you do this a
bit, you end up with scraps to play with.

Printed circuit board fabrication
 

"Dave Plowman (News)" wrote in message
...
In article ,
TonyL wrote:
You do need to use a reasonably accurate combination of level and time
though - like any exposure. And the coated board is rather expensive
to experiment with.


I would guess for calibration....a timer and a 1 cm by 10 cm strip of
coated board with sections exposed for various time periods.

Yes - with a light box which I have. But with the sun it would vary
according to time of day and year - even on a cloudless day?

IIRC, some ovens with exposed elements can be used too.

Wouldn't that be IR. ?

Printed circuit board fabrication
 

In article ,
Arny Krueger wrote:
You do need to use a reasonably accurate combination of level and time
though - like any exposure.

Not like *any* exposure. The "negative" generally is line art, thick
black over transparent film. Very, very high contrast. The "film" is
designed to be very tolerant of small exposures to light. It wants to
produce a high contrast "picture".

Oh it's not as critical as a photo - but you still need some care. I'd
have no idea how long it would need in the various flavours of sunlight we
get in the UK.

--
*If all is not lost, where the hell is it?

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

Don Pearce wrote:

Radiospares used to do UV sensitive double sided board. It was
covered with black plastic, which you could use as a resist if you
fancied just cutting the pattern with a scalpel. No idea if they
still stock it.


Just checked - they do.


Thnks Don.

Printed circuit board fabrication
 

David Looser wrote:
"TonyL" wrote in message
...
Dave Plowman (News) wrote:

You do need to use a reasonably accurate combination of level and
time though - like any exposure. And the coated board is rather
expensive to experiment with.


I would guess for calibration....a timer and a 1 cm by 10 cm strip of
coated board with sections exposed for various time periods.


Not a lot of use with sunshine, as the UV content varies from
minute-to-minute depending on cloud cover.


Quite. It is going to be a UV box, either home made or bought.

Printed circuit board fabrication
 

On Sun, 8 Feb 2009 10:38:19 -0000, "TonyL"
wrote:

Don Pearce wrote:

Radiospares used to do UV sensitive double sided board. It was
covered with black plastic, which you could use as a resist if you
fancied just cutting the pattern with a scalpel. No idea if they
still stock it.


Just checked - they do.


Thnks Don.


Welcome - just to be clear, I meant the black plastic could be a photo
resist, not an etch resist.

d

Printed circuit board fabrication
 

In article ,
TonyL wrote:
Quite. It is going to be a UV box, either home made or bought.

A selection of tubes he-

http://www.tlc-direct.co.uk/Main_Ind...s_2/index.html

Some fittings that might do he-

http://www.tlc-direct.co.uk/Main_Ind...lar/index.html

Or do a search for a twin ballast for the tube size you want.

A small toolbox with lid could be a suitable case, with a glass platform
fitted and sponge in the lid to press the transparency and board to the
glass.

Paint the inside white for maximum reflection - you might have to make up
a reflector shaped sort of ^^ in cross section.

They are quite pricey to buy due to low volumes of production - although I
haven't really looked on Ebay, etc. My guess is you could make one at a
parts cost of approx half of buying one.

Remember to print the transparency mirror image as you want the 'print'
side in contact with the work to avoid refraction effects.

--
Is the hardness of the butter proportional to the softness of the bread?*

Dave Plowman London SW
To e-mail, change noise into sound.

Printed circuit board fabrication
 

On Sun, 08 Feb 2009 11:43:28 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
TonyL wrote:
Quite. It is going to be a UV box, either home made or bought.

A selection of tubes he-

http://www.tlc-direct.co.uk/Main_Ind...s_2/index.html

Some fittings that might do he-

http://www.tlc-direct.co.uk/Main_Ind...lar/index.html

Or do a search for a twin ballast for the tube size you want.

A small toolbox with lid could be a suitable case, with a glass platform
fitted and sponge in the lid to press the transparency and board to the
glass.

Paint the inside white for maximum reflection - you might have to make up
a reflector shaped sort of ^^ in cross section.

They are quite pricey to buy due to low volumes of production - although I
haven't really looked on Ebay, etc. My guess is you could make one at a
parts cost of approx half of buying one.

Remember to print the transparency mirror image as you want the 'print'
side in contact with the work to avoid refraction effects.

I made one years ago for the cost of four fluorescent tubes, holders
and ballasts. The box was wood, and the glass was a spare pane from
the greenhouse.

Incidentally I took care of registration of the two sides by stacking
the two artworks on top of the board, drilling a pair of holes at
diagonally opposite corners and eyeballing the holes to line things
up.

d

Printed circuit board fabrication
 

Don Pearce wrote:
On Sun, 08 Feb 2009 11:43:28 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
TonyL wrote:
Quite. It is going to be a UV box, either home made or bought.

A selection of tubes he-

http://www.tlc-direct.co.uk/Main_Ind...s_2/index.html

Some fittings that might do he-

http://www.tlc-direct.co.uk/Main_Ind...lar/index.html

Or do a search for a twin ballast for the tube size you want.

A small toolbox with lid could be a suitable case, with a glass
platform fitted and sponge in the lid to press the transparency and
board to the glass.

Paint the inside white for maximum reflection - you might have to
make up a reflector shaped sort of ^^ in cross section.

They are quite pricey to buy due to low volumes of production -
although I haven't really looked on Ebay, etc. My guess is you could
make one at a parts cost of approx half of buying one.

Remember to print the transparency mirror image as you want the
'print' side in contact with the work to avoid refraction effects.

I made one years ago for the cost of four fluorescent tubes, holders
and ballasts. The box was wood, and the glass was a spare pane from
the greenhouse.

Incidentally I took care of registration of the two sides by stacking
the two artworks on top of the board, drilling a pair of holes at
diagonally opposite corners and eyeballing the holes to line things
up.

d

Hints&tips noted. Thanks all.