A pair of Airfix Hawks in 1/72. Finished.

[hendie]

Very nice work over the last few weeks Steve.  I am in awe at the quality of the etch you have produced, and in such a short time too.

 

May I suggest for annealing - place the MDC etch between two heavier brass sheets, clamp if necessary, and anneal those.  The heat should transfer readily enough, and a solid sheet either side of the MDC will hold all the zig-zaggery in place.

With such fragile etch, I'd be afraid that any heat approaching the annealing temperature will just frazzle the etch if no support is provided.

[HomerJ_757]

Steve,

Just caught up with the last eight or nine pages and all I can say is, wow!  The cockpit looks excellent and then you go bonkers with the placcy VGs, only to make ‘em yer sen using Heisenberg technology.  The patience, skill and determination are amazing and the support and advice from fellow BMers v entertaining.

 

 

[Ex-FAAWAFU]

100 pages, Mr. F; congrats!

 

<raises bat; surveys field; takes fresh guard>

[Fritag]

 

On 12/10/2017 at 5:58 PM, Navy Bird said:

I used an etched MDC from Eduard on the inside of my Harrier FRS.1 kit, and it was fairly easy to get it to conform to the compound curves required. It retained the curvature nicely and I attached it to the inside of the canopy with Future. It's still there - hasn't fallen off yet. 

 

Thanks Bill; I’ve been off and found (or rather found again having read it first time around) the FRS 1 thread and reread the relevant posts   It’s a comfort - and reinforces me in my view that Klear will do the adhesiving type trick.

 

.....But......thinks.....everybody knows that just cos Navy Bird can do something don’t mean the rest of us is capable..... 

 

21 hours ago, hendie said:

May I suggest for annealing - place the MDC etch between two heavier brass sheets, clamp if necessary, and anneal those.  The heat should transfer readily enough, and a solid sheet either side of the MDC will hold all the zig-zaggery in place.

With such fragile etch, I'd be afraid that any heat approaching the annealing temperature will just frazzle the etch if no support is provided.

I’m afraid of frazzled etch too.  The sandwich idea sounds like a pretty bloomin good idea to me 

 

On 12/10/2017 at 10:32 PM, fatalbert said:

Just a thought,could you not anneal the brass before etching it?

 

Hmm, dunno; but at my muppet level of knowledge of metallurgy and chemistry I don’t see why not.  This also sounds like a pretty bloomin good idea to me 

 

5 hours ago, Ex-FAAWAFU said:

100 pages, Mr. F; congrats!

 

<raises bat; surveys field; takes fresh guard>

 

Ta Crisp -  tho unlike the flashing blade deployed by a certain notable BM’er in his Sea King thread - an innings that simply raced to a century - this one  is more akin to simply occupying the crease until bad light stops play............

 

Been down in London since Friday and am on the train on the way back now; hoping to take guard again this afternoon......

[keefr22]

8 minutes ago, Fritag said:

 this one  is more akin to simply occupying the crease until bad light stops play............

 

There are times when England could do with a Steve 'Boycott' Fritag....!! 

 

Keith

[perdu]

Oh

 

Clicky-ba

 

😨

 

 

 

 

 

I've seen commercial etch wither simply by waving a lighted faglighter at it, seriously suspect the brass reinforcing to be a bon mot

[huvut76g7gbbui7]

2 hours ago, Fritag said:

akin to simply occupying the crease until bad light stops play.

Not shinty then?

About 40 years ago whilst visiting Romford,my friend announced that he would take me to Lords to watch a cricket match.

I agreed and said 'before we go what's an over?'

We went to Mildenhall and Lakenheath.

[Fritag]

I'm satisfied based on @Navy Bird's experience using Eduard MDC on his Sea Harrier and my own previous efforts with wire, that an etched MDC can be made to conform to the canopy-  and so as an avoidance activity from proper modelling I've continued to play with the MDC etching process 

 

My first effort (above) was reasonable but I was a unhappy with how rough and crude the the edges were generally.

 

After a bit of reflection I decided that the problem was with the inkjet Artwork not being black enough and letting some UV leak through the black during the UV exposure process.

 

The problem that gave was that it allowed the parts of the negative resist that I needed to remove with the developer solution (and so didn't want exposed to UV light) to in fact get a little exposure to the UV light, which then hardened the unwanted resist a little and made it partially resistant to removal by the developing solution.

 

This then meant that the brass needed longer in the developing solution to get rid of the unwanted (but partially hardened) resist and in the process the properly exposed and hardened resist making up the pattern for the MDC got a little softened and the edges got eaten away a little and became rough and a bit crude.

 

Anyways.  The solution (short of buying another printer!) was to sandwich 2 sheets of printed OHP slides together to make up each side of the Artwork (An idea I picked up browsing t'internet).  It needed careful lining up and taping but doubling up this way effectively made the black that much blacker and impermeable to the UV light.

 

So in this picture you're actually looking through 4 printed OHP slides.  2 for the front, taped together; and 2 for the back, taped together; and then the front and back taped at ones side to form a hinge and keep the front and back lined up when the brass was put in between.  Clear?

 

 

I also modified the artwork slightly to open up the zig zags a little and try and improve the chances of a better reproduction in brass.

 

For test I made 2 sets of artwork.  One with the MDC in a 0.5pt line (which if my maths is correct is 0.176mm) and one with 0.6pt (0.211mm).

 

And using the above artwork and 0.005" brass sheet (0.127mm) I got these two after developing.  The 0.6pt one is on the left and you can see that the lines are bolder.  The unwanted resist came off much more quickly in the developing solution and the lines of the MDC came out crisper -  which I think showed that I'd correctly identified the problem.

 

 

And after a bath in etching solution and stripping away the resist:

 

 

 

Much neater than my first effort!  I could use these 

 

The finer lines of the 0.5pt one will probably look better, and being 0.005" brass it's robust enough to survive handling.

 

As you can see - I'm still not quite reproducing the fine detail in the zig zags - and it may well be that I won't be able to with the limitations on my home-brew facilities; but I'm happy enough with these results  - and I think they look good enough that I shan't worry too much about it 

 

 

 

Edited October 18, 2017 by Fritag

[Brandy]

Nicely done. I agree that the .5pt look better.

 

Ian

[hendie]

ah, there's nothing like a good root cause investigation... 5 Why's and all that.  Then coming up with the appropriate cause is just icing on the cake.

 

Very nice etching sir. You can be justifiable proud of those.   Do you think 4 pt would be achievable?   One thing which may (or may not) help - I was going to buy an aquarium cheapo air pump and air stone thingy to use in my set up (when I ever get around to it).  I have read that the air bubbles help agitate the etching solution ensuring that it gets into all the nooks and crannies and makes the process more efficient.  The agitation also helps ensure that any particulate is removed and helps fresh etch juice to keep moving around the brass

Sounds logical to this numpty.

 

Your artwork certainly seems crisp enough so I wonder if the bubble method would help the etch get into those corners to sharpen up the zig zags

 

 

[perdu]

Those on the right look best to me too

 

Just thinking it over, Hendie and Fritag combining to bring quality etch to the modelling fraternity

 

Kinda warms the cockles of your heart doesn't it

 

They do look brilliant Steve

 

Well done

 

👍

[giemme]

Another vote for the thinner etch here Outstanding result

 

44 minutes ago, perdu said:

Just thinking it over, Hendie and Fritag combining to bring quality etch to the modelling fraternity

What a great thought!

 

Ciao

 

 

[Fritag]

35 minutes ago, hendie said:

Do you think 4 pt would be achievable?

 

I didn't after my first rough-edged attempt - which is why I experimented with 0.5 and 0.6pt   But I do now....

 

I've actually already amended the artwork to 0.36pt (which took all of about 30 seconds) which equates to 0.127mm and so is the same line width as the thickness (depth) of the 0.005" brass sheet.

 

Such apparent accuracy is misleading rather than realisable with my inkjet printer and amateur processes - but it's definitely worth having a go with a thinner line.

 

1 hour ago, hendie said:

One thing which may (or may not) help - I was going to buy an aquarium cheapo air pump and air stone thingy to use in my set up (when I ever get around to it).  I have read that the air bubbles help agitate the etching solution ensuring that it gets into all the nooks and crannies and makes the process more efficient.  The agitation also helps ensure that any particulate is removed and helps fresh etch juice to keep moving around the brass

 

Blimey that's proper clever engineer type thinking - you've gotta remember that I'm only a driver-airframes cum reluctant lawyer - that said a few moments on google suggests that cheapo mini aeration kit can be had for under a tenner.......

 

One thing tho' - at the mo' I've only been using about 50ml of etching solution in a small beaker and I don't particularly want to use very much larger quantities of solution in a larger receptacle.  I'm not sure if any sort of aeration device would work with such small quantities.

 

2 hours ago, hendie said:

Your artwork certainly seems crisp enough so I wonder if the bubble method would help the etch get into those corners to sharpen up the zig zags

 

Yes it's crisp but if you look closely I think some of the fine definition is being lost in the UV exposure and then a bit more in the etching.  I s'pect you're right about the bubbles tho'

 

1 hour ago, perdu said:

Just thinking it over, Hendie and Fritag combining to bring quality etch to the modelling fraternity

I think wot we need is man of engineering ability and know-how (i.e. hendie ) to get etching.........there must be lots of bits of Wessex and Pullman carriage that are crying out to be etched......

 

 

[Martian]

I am looking forward to these going on the canopies.

 

Martian

[TheBaron]

Work to be proud of on developing that PE even further Steve - alchemy and aircraft, you just can't beat it!

 

As with oul ET above, much in anticipation to see it applied... when you're happy the time is right of course.

[hendie]

4 hours ago, Fritag said:

Yes it's crisp but if you look closely I think some of the fine definition is being lost in the UV exposure and then a bit more in the etching.

 

Now that I look closer I see that you are right.   The artwork appears sharp, the exposure loses a bit of definition in the zig-zaggeries, and the final etched part looks to be exactly the same as the exposure.  Now if we can just figure out why the edges are getting the fuzzies...

 

I did come across a post out in tinterwebland where someone was having difficulty with etching, and it all boiled down to the type of ink.  He changed ink and got success. I dunno if that's what's happening here though.

 

I did come across this guy though - his work is truly astounding.  The only difference I can see between his method and yours is that he has his artwork professionally printed

 

 

This one gets really sharp results from home printing

 

 

 

The micro-mark sheet certainly seems to produce a sharper image - Could it be down to the quality of the OHP sheet?

 

Now I'm intrigued enough to consider ebaying the stuff and trying it out (though SWMBO better not find out or I'll be in trouble again)

 

 

 

[perdu]

Go on, go on, you know you want to

 

Along with dozens, nay thousands of us out here

 

I was wondering if the definition is down to the intensity of the u.v. source

Back in the day when we printed silkscreen the masks (green gelatine sheets for transfers) were exposed on a swivelling frame to u.v. from a huge arc light

 

Lashings of light from that

 

"Goggles, gloves and aprons on please Bill."

 

W H O M P H !  crackle......

 

Happy days huh

[Leonl]

Excellent result, .5pt looks better. .4pt, you know you want to!

[perdu]

I expect you have seen this Steve but my early morning waking question was "what intensity UV is best for photoetch resist?"

This googled straight out at me

 

http://www.piclist.com/Techref/pcb/etch/photoresists.htm

 

He suggests a yellow or green may be better and I can see what he means

 

When I'm painting watercolours or acrylics brushes with yellows in are often more difficult to wash out

 

Might be worth a try huh?

 

[hendie]

interesting reading Bill - thanks.  Which prompts me to ask a couple of questions... 

Mentioned in that article is the statement the ink or toner side MUST be placed directly against the stock; otherwise the thickness of the media will allow the exposure light to shine back up under the mask, resulting in a fuzzy edge

Steve, just wanted to check that this is how you're doing things? (I waded through the past 10 pages but wasn't sure which way you were laying the artwork down)

Another suggestion - I see that your registration marks are rather thick. It's possible that a slight offset of the OHP layers may be happening and not really noticeable with those cross-hairs.  I'd go for the thinnest lines possible for the cross-hairs to reduce the chances of any offset.

 

I'm getting the itch....

 

[Fritag]

Hmm,

 

Very interesting article and vids.  Thanks @hendie and @perdu

What I found particularly interesting was that (as hendie noted) the contributors in the first vid got his artwork/masks professionally printed and the the second (between about 2:00 and 2:45) did a side by side demo to show how much better the micro-mark Pro-Etch Inkjet Film was than OHP sheets for producing the masks.  The demo of the problems with OHP sheets mirrors my own experience - which is why I've had better results printing on the OHP sheets I have at the moment at just middle quality settings (to avoid the ink pooling and cracking as it has at higher quality settings) and then sandwiching two sheets together.

 

I'd definitely try the Micro-Mark Pro-Etch Inkjet Film in preference to OHP slides...........but I can't find it for sale by any UK suppler and not even on evil bay from outside the UK.    The only place I've seen it is on the Micro-Mark US website - which would ship to the UK but then it costs about $30/£23 for 6 sheets including shipping - and that sort of expense is disproportionate and p'raps more importantly takes the edge off of the fun of DIY.

 

For similar reasons I don't think I'd be keen on getting my masks professionally printed.  By preference I'd rather get the best results I can DIY.  That's probably not logical (daft even) but I 'spect many of us would feel the same way.  Of course If I didn't have a printer I'd have no alternative - and then I wouldn't feel guilty about it either 

 

Actually I might well have got the Micro-Mark pro-etching kit as my intro to DIY etch if it'd been available in the UK - although I already had a laminator and so might have balked at the idea of buying a second one! - but in any event its not sold in the UK (I just had another look on evil bay and you van get one shipped from Greece of all places but it'll cost £125!).

 

Anyways - I couldn't really put a price on the fun I've had following @Cheshiretaurus's lead and experimenting - and that's the most important thing to me.....(it's the journey as they say on 'Strictly' )

 

The vids do correlate closely with my own experiences tho' and I'm convinced that problem I've had with getting the fine definition in the MDC zig zags is a down to the difficulties with getting a very sharp opaque print onto a single OHP sheet so as to get a very fine sharp transfer from the masks under UV light.

 

I was interested to read in the article Bill found that sometimes a different colour than black is actually more opaque - although the article is quoting Epson brand colours and I've got an HP printer!- worth a play and I could certainly try a medium to dark green effort 

 

The other thing I found very interesting was that the contributor in the first vid was doing single sided etching with excellent results.  I don't need to do any half depth etching for the MDC and single sided etching would simplify the preparation and take away the need to get the front and back lined up accurately.  I shall definitely do a test with single sided etching.

 

I don't think the problems I've had with definition is down to the registration marks.  I say this because the purpose of those is (just) to line up the masks and I've achieved that well with the masks I'm using for the MDC - there's not been any issue with the front and back sides being slightly offset altho there may be almost imperceptible offset in the sandwiched layers making up the front and back masks.  That said, I probably could and should make the registration marks thinner still and indeed hendie is  prescient in that I have been progressively using thinner lines to date! (but Nb that in the photo I posted about you're looking somewhat obliquely at 4 layers of OHP slide lined up and taped together so there an element of optical illusion in how thick the marks look).

 

I think the problems I've had could be down at least in part to the unavoidable thickness of the sandwiched masks made from doubled sheets of OHP - but it may also be that I've not been paying enough attention to the need to get the masks squeezed tight up against the brass.

 

Also (to answer hendie's question) I've  always arranged the inked side of the masks on the outside to avoid any chance of transfer to the resist - and so I could well have been getting UV shining back up underneath the mask as mentioned in the article.   Cor - it'd be good if a simple modification changing the inked side to the inside solved the problem in one go wouldn't it!.  It'll be thanks all round to both Bill and hendie if that does the trick!!!

 

The other thing I could try is something CT mentioned in his tutorial - which is to remove the protective film from the resist before exposing it to UV under the mask - although he warns that it might stick.

 

I have to say tho' that in overview, and having seen the vids I'm not unhappy with the results I've been getting so far.  The MDC in 1/72 is quite small and the lines are probably at least as fine as the stuff the chaps in the vids were etching and so I'm not disheartened with the comparison.  I'd like to get the definition better - perfect would be nice!  - but if I've reached the limits of what I can do with the printer and kit that I've got then I think I'll be happy enough 

 

15 hours ago, hendie said:

I'm getting the itch....

 

Its gotta be scratched now hendie  You know it makes sense........or if it doesn't, you know its inevitable anyway...........

Edited October 20, 2017 by Fritag

[Tomoshenko]

Notwithstanding your results, you make a good point about the DIY aspect and the "modelling journey" as it were. I do enjoy the home made, home brew scratch building aspect of modelling, even though my efforts are not as good as the professionally manufactured aftermarket wares. That said I think you should be pretty chuffed with your results, as well as providing us with an entertaining and informative thread - keep it coming. One thing I need to ask though, how do you dispose of the chemical waste afterwards? Will you store it in a glass jar or similar then take it down the local tip?

[perdu]

Epson

 

Hmm

 

I've got an Epson printer

 

Cost me £3 at the local big boot sale, ex-display no box, get it off my table please

 

He wanted £8 at first

 

Best buy ever at a boot sale, it is a superb scanner too

 

'Nuff of that, if you want Epson printing let me know but most of my ink is generic and gets the nag screen monthly

"Epson genuine blah blah..."

 

If you need I can pop to Tesco and get Epson ink, no problem

 

The mystyck vgs I have are certainly sharply detailed enough

[hendie]

8 hours ago, Fritag said:

but then it costs about $30/£23 for 6 sheets including shipping - and that sort of expense is disproportionate and p'raps more importantly takes the edge off of the fun of DIY.

 

completely understand Steve.   Have you googled for high resolution ink jet film ?  I found a few on a quick google and I wonder if that's what Micro Mark is touting.

 

8 hours ago, Fritag said:

By preference I'd rather get the best results I can DIY.  

 

We can all go out and buy the highest quality resin part, etch, transfer, whatever, but there's nothing quite like doing it yourself is there

 

8 hours ago, Fritag said:

The other thing I found very interesting was that the contributor in the first vid was doing single sided etching with excellent results.

 

I think you only need double sided etch when you are trying to create some surface detail on the brass. 

 

8 hours ago, Fritag said:

Cor - it'd be good if a simple modification changing the inked side to the inside solved the problem in one go wouldn't it!.

 

Sure would!  and what have you got to lose?

 

8 hours ago, Fritag said:

I have to say tho' that in overview, and having seen the vids I'm not unhappy with the results I've been getting so far.

 

I think what you have been getting is excellent so far, but knowing your past work....  just a bit more trial and error, and it will be perfect

 

8 hours ago, Fritag said:

Its gotta be scratched now hendie  You know it makes sense........or if it doesn't, you know its inevitable anyway...........

 

I've already got the artwork completed for a train load of Pullman Parts  (    ) - done months ago. I may well pull the trigger this weekend on an order of nefarious substances and electrickeries.

[John Laidlaw]

This may be of interest, or horror - a method that involves bubble-agitation and hot acid.

 

https://culttvman.com/main/acid-etching-part-2-by-david-merriman/