Yamaha YZ250 - done :)

[Will Vale]

Always glad to see an OT rant

I dick around with Tamiya RC stuff from time to time, with brand loyalty engendered by those awesome videos in Beatties in the '80s when I couldn't afford one I'm not seriously into it but sometimes I get the urge to build and paint one (and then mess about outdoors) - I have their VW Beetle, one of the rally Subarus on the vaguely off-road chassis (which is currently full of dust + gravel) and the CR01 Land Cruiser.

Funnily enough, the thing which got me interested in the 1/6 bikes was seeing a couple on Stellamodels and thinking that Tamiya had ventured into RC bikes Obviously not, but the big kits are still pretty cool.

I've been looking after my daughter nearly the entire weekend while my wife's been at a conference, but I did get some time this afternoon and evening to deal with some unpleasantness I'd been putting off, namely cleaning up the crankcase and associated bits. I ended up doing the exhaust and most of the large engine components at the same time:

(click for bigger)

The exhaust wasn't too bad once I'd figured out how it went together, I worked a bit at a time and used *lots* of clothespins, then pared down the seam a bit after it was dry since it looks a bit over-scale. The cylinder head fitted well and required very little clean-up, although Mr. T. could have put the pin marks on the insides of the fins, surely? The carburettor, intake and air cleaners were a joy. The crankcase, on the other hand, was a right sod.

Checking the internet, the seams are in the right place (the two halves of the real one join there) but as you can see from the filler it had a fairly nasty step, trapped between the relief on either side. I've cleaned it up as best as I can, I'm going to prime it and see if I really need to improve the surface or if I can get away with it... I doubt it's worth reinstating the join line now the step has been removed.

I've also been plugging away at the frame, I think one more filling and sanding session and I can prime it:

I haven't taken pictures, but the gloss white bits have dried up really nicely.

Will

Edited March 10, 2013 by Will Vale

[Will Vale]

Finally got some primer on! I put the swingarm (sp?) together and added some welds to that and the frame using Tamiya's gel superglue, which has the right sort of blobby feel, shrinks a bit and is also easy to wipe away with a cotton bud. They're quite subtle (apart from a couple which I need to sand back) but I think they'll show up under semi-gloss paint.

(click for bigger)

While I was at it I primed the rest of the mechanical bits I've assembled, and did some clean-up and re-priming. I'd missed the sprue attachments on the crankcase and chain covers, and needed to clean the engine seam up more. I also filled the bases of the fins and sanded back so they'd be perfectly flush with the base of the cylinder head.

Seeing the close-ups is a bit like seeing the model for the first time - I didn't realise there was a part number (or something) on the cylinder head in behind the fins, but there it is, sharp as you like.

The last group of bits to be done were the exhaust components. I think there's a little bit of filling left to do, and I made the odd mess of triangles on the vertical pipe into a square block with a file - I think this is an attachment point for a rubber stop where the pipe goes around the frame?

And finally I plucked up courage to de-chrome the chromed parts. The smaller sprue with the suspension was like magic, the chrome just melted away in a bath of Domestos:

The larger, shinier parts (handlebars etc.) are going rather slowly - the chrome has come off in spots, I wonder if might have been clear-coated?

It is, all in all, a three pipe problem.

W

Edited March 11, 2013 by Will Vale

[Will Vale]

I've been painting bits on and off, the frame is black now, as are the engine, air cleaners and other bits. I decided to deviate from reality and paint the exhaust in steel (it should be... guess what... black) because it looks so cool on the works bike I linked to earlier.

After I think 36 hours the chrome came off the shinier parts cleanly. They're really nicely moulded - very smooth surfaces and minimal mould lines, but it'll still be good to clean those off the handlebars, and there are the attachment points to consider.

Pictures tomorrow hopefully.

Does anyone have any tips about cleaning up the rubbery (PE = Polyethelene?) parts? There are various fixings with integral cables which have quite a bit of flash - like the ignition wiring. On a like note, there's a web between the tyre blocks - I think I can just pull this out, but what about the mould line on the tread? I've heard people talk about freezing rubber tyres to make them sand-able, but I've never tried it.

Thanks,

Will

[Mark]

Hi Will, yes, the 'freezing the tyre' trick works quite well. Lovely work so far!

[Will Vale]

Thanks for the tip! Haven't tried it out yet but it won't be long.

There have been a couple more painting sessions since last time, and I've been slowly adding to my collection of bits. I've just finished cleaning the AB so I thought I'd take a quick shot of what I've done so far - not a pretty well-lit shot, just a quick one

(click for bigger)

I have almost enough bits to actually put a sub-assembly together - the monoshock and forks are doable, but I need to polish and paint the inner rod for the monoshock - it's just gloss black at the moment. There's also a wee seam to fix on one of the front dampers which is going to need a lot of care.

I have also (as you can see) lost my Alclad cherry - 37 is probably quite late for this, but we all mature at different rates, or so I'm told

Quite a good experience - I did the dull metals over Tamiya grey primer, and the shiny over Tamiya gloss black or semi-gloss back (rattle cans) - you get a nice difference in finish. The Alclad goes down the airbrush like a rat up a drainpipe, I was surprised how often I had to refill the cup compared to painting with acrylics!

I'm not sure if the lower ends of the forks (damper bodies?) should really be chrome - they're definitely less shiny than the inner rods in pictures of the real bike, but I'm not sure that the polished aluminium isn't a touch dull. I suspect I won't be changing that at this point, mind you - I think it'd mean stripping a whole lot of stuff back and it doesn't look too bad. I should at least wait for some natural light and see how that looks.

One interesting thing - the shiny chrome parts have some kind of varnish over the plastic which is super strong. I tried to remove it with alcohol, and when that didn't work lacquer thinners, but it was impervious to both - maybe it's some kind of epoxy? It seemed stable enough so in the end I just scraped the mould lines, sanded the parts, and painted over with the rattle can black. So far, so good.

Need to get some Alclad chrome for the shock rod and the handlebars now. I also need to figure out how on earth I paint around the spokes since parts of the hub are moulded integrally and they need to be black. It may be that the inner and outer hub parts cover this area up, but I think they don't totally. We'll see.

Cheers,

Will

[Will Vale]

Cleaned up and painted black (gloss and semi-gloss, thrills!) another 31 sub-sub-assemblies tonight. Basically everything left on the sprues apart from the bolts. Knackered now!

I'm slowly coming to the conclusion that I'm going to have to de-chrome the wheels - I doubt paint will stick readily and I need to go around all the spokes in black. My original plan was to spray them with Testor's Dullcote to tone down the gloss but I think that might not be sufficient. Probably easier to spray them black all over, then mask the hubs between the spokes and go over with Alclad. I can also clean up the spokes if I do that - yay, sort of

I'm also losing the fight with the fuel tank - I sanded out a scratch last night and gave it a couple of coats of white in the relevant area, but got some bubbling. So I sanded that out and touched it up, and it bubbled again. I wasn't sure the first time, but the second time I'm sure I just had way too much paint on there. I'm not normally (quite) this clumsy, but the tank is hard to hod and I suspect that's a factor. I opted to wipe out the thick bit with lacquer thinner, so once that's all set again I'll have to sand the edges and re-do it. I wouldn't need to prime it, but the thinner crept around to the inside of the tank (where I was holding it) and there's putty visible there. Grr.

I'm sure I'll defeat it in the end.

Will

[Will Vale]

Still plugging away at this - I've been painting the base metallic colours on pretty much all the remaining bits apart from anything which needs to be chrome. I've also put the forks together and started detail painting on the exhaust. I'm not wild about the wobbly fork gaiters (boots?) but I think maybe if I slide a tube between the fork and the rubber it will straighten things out?

(click for bigger)

This is a test fit but it's starting to look a bit like a bike! Lots and lots of detail painting and light weathering to do, probably the engine is next up.

The exhaust has had a mottling of polished aluminium over the steel base (which I buffed first to get a nicer surface). I attempted to shade the weld seam with pale burnt metal and then neat steel again in the middle, but I find it quite hard to control the lines with Alclad - it seems to go much quicker than acrylics. It must've been good practice though because when I went back to apply a blue glaze and some brown acrylic to kill the shine around the seam itself it seemed to go quite well.

Finally I rubbed the seam with a lead pencil. It's probably a bit over-done but I think it looks cool, and approaches the finish on the works bike exhausts I linked to earlier. Since that's my main weathering/finishing reference at the moment (along with eBay pictures of vintage components for sale!) my excuse will have to be that someone tweaked their production bike a bit to make it look more trick

One last pic, which shows the superglue welds - quite a good one on the exhaust bracket, a less good effort on the frame tube joint:

Lots of detail painting to do now, plus the exhausts need a bit of buffing I think. I also need to get on top of the wheels this week.

Cheers,

Will

[Bengalensis]

Lovely paint and detail work. I like the exhaust painted like this. I hope the tank will sort itself out, now that the pipe probably can't be smoked to solve problems anymore...

That rubber boot would probably be easily sorted with some internal support I guess. It's always a potential problem with these rubber/PVC parts in kits, I much prefer fixed plastic/resin/metal parts and a fully static model.

[tcstom]

Crikey! I've had bikes that look less real than this. Very well done!

[Natter]

I'm with tcstom, this looks real.

[Graham77]

I know very little about bikes but have watched enough "American Chopper" to appreciate how close to real you have achieved so far. Can't wait to see the finished product now. Good job

Graham

[Will Vale]

Thanks folks! All I know about bikes is from this group build and the Tamiya manual, so I've been having to study pictures and try and figure out what things are and how they should be finished.

I've mainly been painting bolt heads for the last couple of days - one big session and one small one. I also re-sprayed the engine and Dullcoted it to give it a bit of a sheen and stop the acrylic from chipping off again:

(click for bigger)

It needs a good dusting - hopefully the flecks are on rather than in the varnish... It looked pretty good to the naked eye yesterday.

The engine and frame bolts weren't too onerous, but the triple clamps (oo terminology!) were a bit - lots of them, and fiddly too. Luckily the lacquer finish meant I could scrape mistakes away with a toothpick and not harm the black:

It looks like one of the reservoir cap things at the top has split - I didn't notice this before. I suspect it can be repaired with a masking tape reinforcement and superglue.

I'm also quite pleased with this obscure little bit - it's the core for the ignition coil, and in the pics I've seen this looks like it might be zinc plated:

The zinc is a mixture of yellow, green and red glazes over silver-with-a-bit-of-gold metallic paint. It's not iridescent or anything but you kind of get the impression I think.

Hopefully I can get some chrome Alclad tomorrow for the handlebars. I've also stripped the kit chrome off the wheels so I have to be brave and deal with the spokes in the near future.

Will

[Will Vale]

Hi again,

Not had a whole lot of spare time last week, but I got some more bits painted and had a good run at the assembly yesterday and today after lightly weathering the engine.

(click for bigger - can you find all the dust?)

As you can see the engine, carburetor, intakes, exhaust and ignition are all present, and some other bits like the foot pegs have gone on too. I've also built the monoshock but the camera battery ran out. I should be fitting that tomorrow after the maintenance decal has had time to dry up.

On the paint/finish side, I lightly polished the frame tubes to give a contrast between those and the various webs, flanges and brackets. I also added some wear to the lower corners but that needs refining. To give a lightly used look, most of the bolts have had a dark wash, and I've discoloured the cylinder head fins - I was worried about overdoing this but it's invisible on the photo, I'll have another go tomorrow to see if it shows more in daylight.

I found the last bottle of Alclad chrome in the country (really - it's sold out at the supplier) and painted the handlebars. The levers (clutch and front brake?) are in polished aluminium since they don't have as deep a shine as the chromed bits on pictures of the real one. So it should be possible to finish up the forks tomorrow as well.

Annoyingly, while fitting the ignition coil I got some glue on one of the frame members and had to fill, sand repaint and polish the dint out. Fixed now though, and lesson learned.

I'm trying to get basically finished for a club meeting on Wednesday night, not sure if I'll make it but the only real obstacles are now the wheels and the fuel tank, so I'm in with a chance.

Will

[tcstom]

Outstanding, truly a work of art!

[Doug Rogers]

Looks fantastic Will, really nice paint finishing.

[Riggers]

Stunning Will....really stunning finish on that zorst............

ATB

[Mark]

That's about as real as real gets! Superb painting skills on display here Will.

[stringbag]

t

One last pic, which shows the superglue welds - quite a good one on the exhaust bracket, a less good effort on the frame tube joint:

Cheers,

Will

Those welds are spot on, and replicate the original very well indeed.

Jap bikes of the era were very poorly finished in this area with welds like pigeon poo-poo on Nelson's column. Nothing like the finished achieved by today's methods.

The bike builds posted here lately have all been amazing.

Chris.

[Will Vale]

Thanks for all the comments! It's cool when you get things right by accident - I could only find close-ups of the welds on the works bike, which were rough as. I tried to tone them down a bit but didn't always succeed. Just as well

I've done a bit more today. I bit the bullet and started on the wheels by scraping all the spokes - not so much to remove mould lines, but to deal with some mis-alignment issues. I've been wondering how to paint the wheels (black hubs with wire spokes ) and opted to undercoat the halves in semi gloss black. Then I brush painted the spokes from the hub out to about half-way with Mithril Silver.

Once that was dry I cleaned the paint off the mating surfaces, pared away some pin marks which were interfering with the fit, trapped the hub inners in the middle and glued + clamped the halves. I masked off the centers and airbrushed a bit of chrome to see what it'd look like - not good. Big gap at the seam, and lots of the spoke bases were mis-aligned. This despite the fact that the alignment pin was very solid, and the join on the outside of the wheel was perfect.

I thought about it and decided I couldn't live with it, so went round each wheel twice filling the gaps with CA and sanding it out with some home-made mini sanding sticks sized to the spoke gaps. I also did a bit of filing and sanding to deal with the worst of the mis-aligned bases.

The end result was a bit like this:

i.e. a bit rough. I did another round of cleaning and sanding with finer grit paper, and tried to round out the bases with some more CA. The front wheel ended up OK, the back one (above) needs another pass.

I then had to paint the other half of each spoke with a brush, and I still have some touch-ups to do. It's not perfect but it's a lot better than I started with. The rims and spokes should get a bit more life when they've had some gentle washes.

On more fun notes, I got to try out Alclad chrome for the first time on the handlebars (fun!)

and also built up the monoshock and gently weathered the reservoir with washes:

This last picture was supposed to be the swingarm installed, but I've lost the two bolts which retain it Luckily they look fairly simple, so I should be able to make some stand-ins.

Not sure I'll get it all done for tomorrow night now, but maybe I can get to the naked bike stage?

Will

[Doug Rogers]

Look! Are you sure that's not a real bike? That carb looks amazing.

Edited March 26, 2013 by Doug Rogers

[stringbag]

Look! Are you sure that's not a real bike? That carb looks amazing.

I'm beginning to wonder about this myself Doug. LOL

Chris.

[Will Vale]

Cheers gents. I managed to get everything together (temporarily) to take along to the club without the bodywork, and it all fits nicely at the back end. Stupidly I didn't take any pictures

Since then I've finished up the rear wheel and added some shading to the front one with more washes. I've also been working on a base since I was so impressed with

Jörgen's work and what it added to his build. I started with a pre-cut slab of MDF from the art shop - lazy I know, but it saves on finishing and sanding and it's not expensive. I thought it was way too big at first but I was surprised at how big the bike was with its wheels on so it worked out well

I sealed it with dilute PVA, sanded down the edges and sprayed them with Chaos Black from the dregs of a rattle can. More sanding and another coat, then I masked them up. I drilled/gouged a couple of holes in the top surface for ~8mm neodymium magnets and epoxied them in place. Then the top was dressed with lightweight filler, and finally sealed with tinted gesso with a bit of sand in it.

I warmed up the colours a bit with the airbrush and did a little drybrushing (more from habit than need):

(click for bigger)

Once that was dry I made a couple of masks with torn paper and sprayed the whole thing with 3M Super 77 (very sticky spray mount - horrible stuff) before applying static grass and some longer Woodland Scenics "field grass" using Rick Reimer's hairy cigar technique - check out his video for more information:

http://www.youtube.com/watch?v=d2rOO1hN8_U

Amusingly, most of the images and search links for "Rick Reimer hairy cigar" link to my model railway stuff - I'm not sure why this technique isn't better known or more used, since it's pretty awesome.

Once the grass is on the base looked nice from low angles, but pretty bare and boring from above - no good for a model on a table really. I added loads of different scatters and after wetting them with a mist of alcohol set them with a dribble of dilute glue. I'm waiting for this to dry at the moment. The end result is promising, maybe a bit more lush and damp than I was going for , but it'll do for now: I'll tease out some of the grass and remove the clumpier bits when it dries properly:

The bike sits on top thanks to more neo magnets in the tyres - they're just loose for now. It won't stay on if you turn the base upside-down, but it won't roll away either and it's easy to remove for storage.

The stand is from the kit, I'm not sure how to paint it yet - whether the bars should be left bare metal, or the whole thing painted over? I'm intending to have the left side race number plate thing off the bike and leaning against it, otherwise the ignition system is entirely covered up and I'd rather it wasn't

Not long now, hope I can do the last bits in time,

Cheers,

Will

Edited April 1, 2013 by Will Vale

[Bengalensis]

I was just about to write and ask how this was coming along with a day left, I really want to see it finished, when this update appeared. This is awesome Will, so good looking!

[Will Vale]

Two days! (I hope)

[Bengalensis]

Yes, two days of course, I can't count that far sometimes...