hi Missy  might be an idea to practice on a simple  sheet of etch that has been  sprayed Indian reg  to save having to stip of   hwen your not happy .. the paint  the paint lol

Sounds like the compressor might not be powerful enough. What type is it?

I think Nigel's right - it's a case of practice with the bow pen (preferably on something simpler than those frames!). And waiting for the paint to dry would probably help.

Andy

Thanks for the replies you two.

Nigel, yes, it would make sense and I should have painted some more bits earlier. Thanks for the tip though, next time I will do that.

Andy, its a Revell Omega compressor, the fridge compressor type. It has always been fine with the airbrush, do air erasers use significantly more air or something then? I will be more patient next time too and leave the base paint overnight before trying the lining, the paint did feel a little soft when trying the lining today.

...do air erasers use significantly more air or something then?...

Is this the BD-178 thing that Eileen's have been selling recently? I have one of those and for cleaning brass quickly I've been using about 45-50psi, though it should work around 25-30psi for removing transfers, etc. I did make the mistake once of sweeping up the used grit from the bottom of the large plastic box that I use it in and putting that straight back in the cup without sieving it. There were some tiny wood shavings in there and they blocked the nozzle so it needed stripping and blowing out. Also check the moisture trap, it's been very humid of late...

Nick

Not sure about the abrasive gun/compressor tbh. I've just remembered that there's a thread on here about  bowpens and how to use them and set them up. Here it is...

http://www.rmweb.co.uk/community/index.php?/topic/15815-using-a-ruling-pen/

Might be worth a read.

Andy

Is this the BD-178 thing that Eileen's have been selling recently? I have one of those and for cleaning brass quickly I've been using about 45-50psi, though it should work around 25-30psi for removing transfers, etc. I did make the mistake once of sweeping up the used grit from the bottom of the large plastic box that I use it in and putting that straight back in the cup without sieving it. There were some tiny wood shavings in there and they blocked the nozzle so it needed stripping and blowing out. Also check the moisture trap, it's been very humid of late...

 

Nick

Well its the same one but from a different supplier. The moisture trap is fine so I dont think thats the problem. I get airflow through it without any grit, its just when I add some grit it stops working, empty the grit out and once again its fine. Im reluctant to take it apart yet as Im worried it might mean I cant send it back if it comes to that unless I know exactly how to fix it.

Thanks for the advice though Nick.

Andy, thanks for the link, thats very useful. I remember there was a thread somewhere but hadnt searched for it. From reading that thread it comes across as very complicated and a bit scary!

M.

Missy,

It looks are though the pen isn't quite the right shape yet. I found that this took a bit of experimentation regarding getting the profile right. Also, I find gently rubbing some medium/fine wet and dry against the inside of the nib (800 grit is the lowest I'll use) helps remove any burrs that will interfere with the paint flow. Practice on some scrap bits first, unpainted plastic card (but make sure it's clean!) is good if you not keen on having to continually paint up bits of brass for experimentation!

Regarding the paint. Did you thicken it before using it for the lining? Coachman's thread on this is really beneficial as I would have never have thought of this on my own. A condensed version of what he recommends (from memory) is: 1.) Leave the paint for a few days to settle. 2.) Pour out all the oil that has risen to the top. 3.) Stir and add back in about 1/4 of the oil. 4.) Stir again, ensuring the paint isn't lumpy at all.

With a correctly profiled pen this should now provide a nice consistent line as long as the paint isn't too old. I've found that I can line with both Revell and Humbrol paints but still have been successful with acrylics and have not tried cellulose at all.

I would leave the base coat to dry out fully before lining. Also I usually put a coat of gloss on before lining as this seems to help the paint flow. The tender chassis we used was still in it's base plastic so already reasonably glossy.

The air eraser needs around 50-60 psi to work effectively. I've opened out the feed holes in the cut to around 0.7mm as this helps a lot. However this does have the side effect that the nozzle clogs up from time to time but it is a simple matter to remove it and clean. It is still a bit under powered but will get the job done, also I've been using baking powder in mine - about 60-70% as effective as the aluminum oxide but an awful lot cheaper!

Hope this helps and for those with more knowledge than I, please forgive the crudeness of my methods!

Hi Missy,

On a more supportive rather than technical note as supplied by the fine people above, I too have had a pig of a day! One of those occasions where I set aside me and my model time and almost nothing went right. The most successful thing about today was the high quality of my soldering burns to my fingers in fact...

I am sure it happens to us all at or point or another but there must have been an anti modelling miasma in the air today!

Really little CoT looks the absolute business by the way.

All the best,

Castle

As Don and Steve said gloss surfaces should line better. This because they have lower roughness than a matt surface. I believe the paint needs to be a bit thicker than milk and more like pouring cream.

Thanks once again for all the replies, there is some very useful and helpful information there.

Missy,

 

It looks are though the pen isn't quite the right shape yet. I found that this took a bit of experimentation regarding getting the profile right. Also, I find gently rubbing some medium/fine wet and dry against the inside of the nib (800 grit is the lowest I'll use) helps remove any burrs that will interfere with the paint flow. Practice on some scrap bits first, unpainted plastic card (but make sure it's clean!) is good if you not keen on having to continually paint up bits of brass for experimentation!

Thanks Atso, I will take another look at the pen today and see if I can get the tip right. I had a go at it yesterday but I dont think I was that successful. The plasticard idea is good to, thanks.

Regarding the paint. Did you thicken it before using it for the lining? Coachman's thread on this is really beneficial as I would have never have thought of this on my own. A condensed version of what he recommends (from memory) is: 1.) Leave the paint for a few days to settle. 2.) Pour out all the oil that has risen to the top. 3.) Stir and add back in about 1/4 of the oil. 4.) Stir again, ensuring the paint isn't lumpy at all.

No I didnt, its a fresh tin which I did nothing but shake it before giving it a go.

I would leave the base coat to dry out fully before lining. Also I usually put a coat of gloss on before lining as this seems to help the paint flow. The tender chassis we used was still in it's base plastic so already reasonably glossy.

Would a coating of that Kleer work? The reason I ask is its a bit easier to apply than traditional varnish. The finish on CoT was semi gloss.

The air eraser needs around 50-60 psi to work effectively. I've opened out the feed holes in the cut to around 0.7mm as this helps a lot. However this does have the side effect that the nozzle clogs up from time to time but it is a simple matter to remove it and clean. It is still a bit under powered but will get the job done, also I've been using baking powder in mine - about 60-70% as effective as the aluminum oxide but an awful lot cheaper!

Do you mean the 3 holes at the bottom of the cup? I havent figured out how the thing works yet so its a bit harder to find whats wrong with it. I was assuming air comes out of those 3 holes and agitates the grit forcing it down the central tube controlled by the needle valve at the top? From what you said there it sounds like the grit goes down, through those 3 holes? Strange as there is definately air comming out of them. I think a session with Mr Google is called for! I have plenty of grit but the baking powder is a good tip, thank you.

Hi Missy,

On a more supportive rather than technical note as supplied by the fine people above, I too have had a pig of a day! One of those occasions where I set aside me and my model time and almost nothing went right. The most successful thing about today was the high quality of my soldering burns to my fingers in fact...

I am sure it happens to us all at or point or another but there must have been an anti modelling miasma in the air today!

Really little CoT looks the absolute business by the way.

All the best,

Castle

Yes, I know exactly what you mean! I started off this year with all the enthusiasm of a coiled spring to get some good modelling done but so far it hasnt happened! Determination is the secret me thinks..

Thanks for the kind words about CoT too, its good to hear that from someone who has surrounded themselves with the prototypes. As I mentioned in the post that is MkII which isnt quite right (hence using it for painting trials) so MkIII is in the pipeline.

As Don and Steve said gloss surfaces should line better. This because they have lower roughness than a matt surface. I believe the paint needs to be a bit thicker than milk and more like pouring cream.

Thank you Rich, I will give it another go taking into consideration this, and other advice.

M

Missy
This look good- your view that the picture is cruel owing to the enlargement is valid. I'll try and put a 'cruel' enlargment of recent Maxtoke coaches up later as a comparison.
 
My own preference for applying lining is through a tubular pen, using acrylic inks. Nothing whatever wrong with a bow pen, I just don't get on with them, using paint. My background as a draughtsman, who remembers bow pens and razor blades may have something to do with that. But even the tubular pens take practice, each time as I don't use them that often. I too agree that gloss surfaces are best (equally for 'wet' lining or transfers).
 
There is always a case for the use of home made transfers. This is illustrated well by Tim's Baldwin on CF. These do produce really crisp lines for boiler bands etc- in scale terms the transfer thickness is probably quite accurate.
 
I use a Badger grit gun- and this, too, clogs sometimes. usually it is a foriegn object - peice of hair, a 'dust flea', or the like, in the pick-up tube. Even a very small amount of moisture can cause a degree of 'clumping' which can get things glued up.

Richard
 
 

Hello

Missy
This look good- your view that the picture is cruel owing to the enlargement is valid. I'll try and put a 'cruel' enlargment of recent Maxtoke coaches up later as a comparison.
 
My own preference for applying lining is through a tubular pen, using acrylic inks. Nothing whatever wrong with a bow pen, I just don't get on with them, using paint. My background as a draughtsman, who remembers bow pens and razor blades may have something to do with that. But even the tubular pens take practice, each time as I don't use them that often. I too agree that gloss surfaces are best (equally for 'wet' lining or transfers).
 
There is always a case for the use of home made transfers. This is illustrated well by Tim's Baldwin on CF. These do produce really crisp lines for boiler bands etc- in scale terms the transfer thickness is probably quite accurate.
 
I use a Badger grit gun- and this, too, clogs sometimes. usually it is a foriegn object - peice of hair, a 'dust flea', or the like, in the pick-up tube. Even a very small amount of moisture can cause a degree of 'clumping' which can get things glued up.

 

Richard
 
 

Hi Richard. You are right, the picture is a bit of a cruel enlargement, when I first saw the photo on my PC screen I was shocked so much I nearly didnt post it!  It does look much better to the naked eye, well for a first attempt it does!

I did contemplate making some transfers for it (or more possibly doing the artwork and getting someone to print them for me) but after seeing Atsos fantastic results he had with a bow pen and the subsequent quick tutorial by him I decided this was the best method for reproducing the lining on CoT. I personally think transfers for this might be a little too fiddly to do. The plan is to do some transfers for another little project of mine shortly though.

GOOD NEWS on the grit blaster though, I finally got the thing to work!! As suggested above I turned up the pressure to around 60-60 PSI and it burst into life, I even did Atsos other little mod and opened up the holes to get more flow. I have now stripped all the paint off of MkII Cot ready for repainting and even made a start taking the paint off my little Mamod project. The only thing is now I have a container full of 'used' grit, Nick mentioned about sieving the grit, my question is with what?

Hi Missy,

 

I'd be over the moon if I could achieve that level of accuracy in 4mm!!  The detail on that bogie is marvelous and your work in general is sublime.

Thank you PMR, thats really nice of you to say. Its still a big experiment to me right now!

M

Glad to hear you've got the grit blaster working. Atso's mod to the feed holes sounds interesting, I might try that. As to sieving, I used an ancient plastic tea strainer. It has a very fine mesh, though much larger than the grit particles. It was good enough to trap my wood shavings but I doubt it will be a long term solution.

btw. did you notice in the instructions that the bit on the front is labelled "noozle"? I rather like that.

Nick

Glad you've got the grit blaster working! Not sure what you strain the powder with though. In my excitement I've done all my blasting outside and spent an age cleaning up the mess which was only fit for the bin by that point!

I've seen much worse lining from more professional modelers!

I had a chat with Ian Rathbone years ago at a show. His advice on bow pens was to always keep the blades polished. And although he is a pro who lines (superbly) every day, he spends a bit of time every day also practising on cheap plastic bodies to keep his eye in and to check the pen is set up right.

The other priceless tip I learnt from him is that it is often impossible to get lines thin enough using a bow pen. In that case you draw the lines onto the body as thin as you can, and then draw lines in the original base colour next to them to cut into them and make them thinner. If your technique is good enough you can draw anything as thin as you like this way. Often when a model lining looks wrong, it is just that the lines are too thick.