Scratch building a class 50 from card

[sleeper]

I had a choice of three BR blue liveries all blue of course but they vary in the yellow panels. One type is with a small yellow end panel only, one has full yellow ends wrapping right round to include the cab door, but with black round the windscreens and thirdly the one I chose full yellow ends wrapping round but with a blue panel beneath the side windows and yellow round the front windows too.

I was a little concerned that if the doors were yellow and had to be rubbed down it would be near impossible as the doors were recessed slightly.

It wasn't till I got into the masking off that I realised I'd picked the most difficult to mask, there is a little curve in the top of the blue side panel which involved cutting the masking tape round a piece of 3mm plastic tube with the craft knife, all good fun!

This first photo is a really cruel close up of the paint job, it looks better 'in the flesh' probably only because you can choose to ignore the bad bits, whereas in the photo they smack you in the eye.

 

 

I've started detailing it, you can just see some of the grab rails (4) fitted to the front. I'm also working on the headcode boxes.  I'm not happy with these.  I had made them shallow thinking that I could add a deeper front, which I did, but having done so I now realise the boxes should have been deeper from the very start. This has shown up now at this late stage, with the Shawplan 4mm round etched horn grilles I'm going to fit, being a knats too large for the depth of the face of the box. I'll have to solder them to a piece of brass wire and mount them in the mini drill to take them down slightly. A real pain but less work than altering the headcode boxes.

 

 

in this picture are some masks, masking tape cut on the silhouette cutter, this will be stuck to the face of the headcode box to form a guide for painting the domino spots on the face of the box. Will it work? Yes it will, I know because I've already done it once. Unfortunately the dots looked too close together, so the one on the right in the photo is the mk2 version.

I drew the box's face in Inkscape, using a head-on photo as a guide to getting the right layout. I first tried cutting them from a sticky labels sheet but it didn't seem to want to work, the cutter just tore up the label. Next I cut the design on a sheet of copy paper attached to the cutting mat. I carefully noted just where the mat lay in relation to the rollers on the cutter, released the mat and stuck masking tape exactly over the images that were cut into the paper. You can see the black outlines where I highlighted the outer edges with a pen.

I then very carefully lined up the rollers with the sheet again and re-cut the images. My luck was in, the cutter cut right bang on target, in fact there was only half a mil  of tape left on each side. These were carefully teased off the mat with a scalpel and applied to the face of the headcode box. I painted the dominos with white acrylic paint and the places where the horn grilles would go in grey so if they showed through the grill it wouldn't show up. 

What a pity the dots were wrongly spaced because I now have to go all through the procedure again. I wonder if I will have the same luck again?

We'll see!

cheers for now

Roly

[sleeper]

I've done a bit more of the detailing, my luck held with the headcode box alterations. I managed a second time to scribe the face and then remove it from the cutter, first marking the position of the cutting mat by sticking a bit of masking tape to the mat alongside one of the rollers, it was then just a matter of re-entering it using the tape as a guide, spot on!  I've added some handrails, grab rails, buffer beam steps etc. I used 0.45mm brass wire for the rails, fixed with superglue into  0.6mm holes. One little problem I encountered with this was, unlike plastic the card raises up around the drill bit when you drill it, in other words it doesn't cut cleanly and so  I have had to sand the mounds back with a minute piece of wet and dry, very annoying when the paint has been done. I'd considered fitting the rails before the paint job but decided against it as I didn't know just how many coats it would take to secure a decent finish, too many might have swallowed up the hand rails.

In the second picture you can just make out the buffer beam steps, these were another Shawplan etch,they are very very delicate, not long in this world I think.

 

 

 

With regard to the use of kleer to stiffen up the cardboard, as an experiment I thoroughly wetted a strip of 0.45mm card with it and let it dry, it didn't seem any stiffer than before. I also used kleer to stick two bits together, clamping them together overnight, again it was no good as an adhesive. Perhaps if it was soaked for longer it might absorb more liquid.

 

more later

 

Roly

[raymw]

Hi Roly,

 

I've not tried this, but being as you seem to be in an experimental frame of mind ...

 

You can get milling cutters with a reversed flute, used for some thin materials. Perhaps if you were to grind a drill point 'the wrong way' and reverse the direction of rotation, it would not tend to lift the card into the ridge that you mentioned.

 

Alternatively (and I did do this many years ago for fine engraving of metals) make a spade drill from a sewing needle.Cut off the needle eye end, and use one of those diamond slip stones to quickly put a couple of flats on the pointed end of said needle. It is not that you need precise size, but if you did, sewing needles can make a fine tapered broach type of tool.

 

hth,

 

Best wishes,

 

Ray

[sleeper]

Hi Ray,

I'm not entirely sure what you have described. My impression of grinding a drill bit 'the wrong way' means so that the centre is lower than the outside, similar to a Forstner bit but without the point in the middle. I can see that would cleanly cut around the edge of the hole and reversing the direction would tend to force the outside edge of the hole back in, rather than up and away as is usual. Am I on the right track?

The needle/ spade bit idea sounds interesting, did you manage to leave the point intact ? otherwise the bit might tend to wander off centre.

[raymw]

About halfway down page - downcut spiral. http://wiki.imal.org/howto/cnc-milling-introduction-cutting-tools For a normal drill, which rotates clockwise, the spiral is designed to clear the debris from the hole. As you are drilling cardboard, the swarf is unlikely to jam the drill, if either you drill fast, or very slow. Leave the point on the drill, but make the relief in the opposite direction. I hope you are using hss, not carbide drills. Note that this is not the same as a reverse flute drill, used for extracting taps, etc, which when driven in reverse still raises the swarf out of the hole.

 

For cardboard drilling, you may not need to worry about grinding the relief in the opposite direction, just apply a bit more welly.

 

Ray

[sleeper]

Ray,

Thanks for the link, it leads on to some very interesting and potentially useful information., 

On the topic of drill bits I don't have the equipment nor the skills to grind the drill bits. The holes that are the subject of this discussion were merely 0.5mm wide which precludes the 'wellie' treatment too.

The cause of the 'ridge' is due to the cardboard, being a very soft material it doesn't form 'chips' but just creates a ridge instead.

I'm not aware that Forstner bits are available in sizes below 1.0mm, anybody know? 

[sleeper]

Just a quick update, some more detail added

 

 

 

 

I had almost finished this model and had it trapped between my knees while working on it and somehow it slipped out and fell nose first onto the tiled floor. This didn't do it any good, the cardboard sprung back into shape ok but the paint layer was badly cracked (see in third photo).

I made a fine file by gluing a strip of 400 grade wet and dry paper to a 5mm wide strip of plastic and filed down the damaged surface. I filled the damage with a couple of good applications of yellow acrylic paint, then rubbed those down with the file I'd made and finished with a coat of the same colour enamel I'd used originally. It now looks presentable.

In the second photo you can see I've started the numbering, I had a little problem with a couple of the waterslide overhead electric decals curling up and peeling, despite sealing them with Kleer. They are on quite thick decal paper and I suspect they weren't quite dry despite leaving them for over an hour as recommended in the instructions.

Personally I'm not a fan of this type of decal but it's all I could find.

So now I've nearly finished detailing, next some varnish, so more to come.

 

Roly

[sleeper]

Well at last it's finished. After the paint had time to harden off I gave the transfer areas a coat of Kleer and then applied the transfers using HMRS sheet 15 BR blue for the inter-city arrows and the numbers too, then I applied a waterslide data panel from Replica Railways under each number and finally the overhead flash signs also waterslide, from Precision Decals, no connections etc.

This was followed by  a spray coat of Humbrol satin varnish.

Once the varnish had hardened sufficiently I weathered it with acrylics using a very weak wash of white first to give the blue a faded look. When this had dried I applied Humbrol 'smoke' weathering powder and washed this in with a wet brush and then took off the surplus with a large dry flat brush, finaly forming puddles of water on the roof and allowing them to run down the sides,blotting with kitchen roll and rubbing in with the dry brush.

When all this was complete and dried overnight I brushed a coat of matt varnish all over.

I'd already weathered the chassis with acrylics using the same techniques.

Finally body and chassis were re-united, here's the results.

 

 

 

 

 

The last photo is a really harsh cruel close up which shows the model,'warts an' all'. I procrastinated for ages over the 4th photo, but decided that it left the viewer with no illusions as to what this model really is, you must be the judges.

 

My personal impressions of this model now it's finished are that I could have taken more care over the preparation. I also think that  fearing it would be flimsy I have made the sides too thick, especially around the windows. Lack of thought has resulted in the interior around the windows being unsuitable for fixing any glazing to. I have cut the glazing and dry fitted it but have my doubts that it will fit correctly leaving gaps here and there which would look ugly.

Overall, considering this model was an experiment by someone who was still learning how to use Inkscape and the silhouette cutter, it hasn't turned out too bad on the whole, but that's just my opinion. Please do add your criticism, it would be most welcome, as that way we all learn.  

Regards Roly

[Andrew F]

Thanks for sharing this ambitious and very interesting project with us Roly. You've certainly captured the looks of a 50.

 

I do think you should persevere with glazing though as it does have a slightly barren unfinished look if you don't mind me saying.

You'd have to cut the panes from acetate to the exact size for an 'interference fit'. Canopy glue such as Deluxe materials R/C glue is good for sticking glazing and any excess can the rubbed away after, or it can be thinned with water and capillary action can seal the pane in situe.

 

Cheers

 

Andy

[siltec]

Well done. Learning is the best part of the process.

 

My card efforts, to date, have produced mixed results and an awful lot of questions.

 

Decorating and summer means the Cameo has seen little use recently. However I found a link on this site to a source of replaceable blade cutters from China. Tried my luck and no problems, it arrived as ordered. have not tried it out yet though.

 

Keep up the good work. It is a bit like the revival of LPs and and film photography. Perfectioon over the counter is boring. Technology such as scanners, colour printers, 3D printers and CNC card cutters does take the drudge out of old processes.

 

David

[sleeper]

Andy

Thanks for your honest opinion, I don't mind in the slightest. You are right it does have a barren look as you say. Having just finished it after a couple of months work, on and off, I'd hate to spoil it now with bodged glazing but from past experience I know that 2 months down the line I won't care so much so then I might just take you up on your suggestion and glaze it, come what may. 

 

David

Where's the link to your work with card? If you have any questions about problems you may have had post them up on here you might get some answers that will help you out.

I know what it's like trying to partner modelling with work, there's only 24 hours in a day.

As you say modern technology makes things easier, I certainly couldn't have coped with cutting all the openings in all of the sides I've produced to get this model made. For example I've just thrown away about 20 rejected sides from this model and I still have a large polythene bag full of ends, doors, roof layers etc. So Yes, the cutter takes the graft out of it.

I suppose you can liken card modelling to vinyl, film, betamax etc, old tech, but like old cars that you wouldn't have paid £25 for years ago they are now things of beauty to some.

Maybe clockwork motors are the way to go!

 

Thanks Gents for the kind words.