Scratchbuilding C&Cs Mammoth Tank

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Munty
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

Woohoo! My package arrived today and Mike is now my best friend in the whole world! (Though he doesn't know this yet) He sent me even more than I was expecting so Christmas has come early in the Mammoth household today! I didn't want to update my postal situation so I have a little bit of formal brainstorming to share too. After pretty much deciding on the previously posted layout for this area, I'm now able to mock it up with the bits I got from Mike so below are some pics of my pressies and what I intend to do with them. Also enclosed is a request for materials and a few opinion based questions so please read on if you've got this far :D

First my significantly larger than expected package! As you can see I couldn't contain the parts any-more than I could contain myself so I opened it before reaching for the camera :p
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Also included by my beloved benefactor was a full copy of the instructions which just go to show how amazingly detailed this kit is. (I mean look at the size of the box I have and that's only a fraction of it!)
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Enclosed were 2 of each of the following sprues, much more than I'd expected so even more to be grateful for! This first one has some compartment walls and other panels and wires and so on which will be great for final detailing.
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The all important engine sprues!
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Radiators, air filters and other assorted parts (didn't think I was getting these but really happy I did!!!)
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And lastly the gorgeous transmission kit. The flywheel itself is a work of art and there are so many detailed levers and motors that modifying these should be a breeze and a pleasure!
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Onto some minor progress I made a few days ago while I was waiting for a friend of mine to visit. This is the back of the turret. It's not much but it's come out very well given the multiple nasty angles. The top of these 5 pieces aren't level which I guess is due to the angles but I'll fix that later as the final pieces for the turret will all be individually made now the plans are getting less reliable (nice and time-consuming!)
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Now onto the engine room. First off, here it is in all it's glory...
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Obviously that's a lot of space to fill so just chucking some engines in there won't do the job. First thigns first I tried to wall off the excess space by chopping up a cereal box! Temporary measures only I promise... That gave me a new floor and lost about 25mm of height while also giving me a rear wall to what will be the only visible interior section of this build.
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I just feel like I have to share a pic of this flywheel as it's so immaculately detailed. Tragically my camera won't do it any favours but trust me when I say it's got the details sown to the very last bolt head!
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Now please don't anyone be upset by these next few images, they're only very early glue-free mockups!!! I'm certainly not going to dive in with this beautiful kit now that I've been so lucky to get my hands on it. The final build will be done very carefully and slowly to achieve the best look I can from this great little piece. That said, here are a few pieces off the sprue so I can get an idea for exactly how everything will look when finished (and also to help me decide on location and spacing and such!)
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As you can see from those the engine is about 90mm long with the transmission about 50mm wide. For me, I won't be using the trannies in their standard configuration and instead, as already shared, will be mounting them lengthways in the vehicle. This is to represent a direct drive from each engine straight through to the tracks further forward and also one spur from each side which will meet in a transfer box at the centre of the compartment. This will have to be scratchbuilt but I have plenty of great parts to play with including all 4 transmission brakes which won't be used. Here are some shots of what the arrangement SHOULD look like adn what it WILL look like!
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Of course the little gap in the middle will be filled with the flywheel assembly as intended, this is about 13mm when complete giving my finished unit a length of about 150-160mm from dizzy to driveshaft! Anyway onto the important part of how those two fairly small assemblies can hope to fill such a large void... I used the cardboard floor to draw a template for the interior but the details didn't come out great on the pictures that follow. The hole in which the engine is recessed is about 10mm below the rest of the floor while at the back, the transmission will NOT need a hole beneath it. That's one thing I now know which I previously didn't!
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The doodling on the floor relates almost identically to the previous floorplan I posted with battery storage under the central floor of the engineers crawlspace and the fuel tanks provisionally marked in at either side. These are one of the things I'd like advice on though... I think it would be a pretty nice thing to have the tanks visible in this area as it's a good space for them and it'll save me trying to detail 2 big flat walls! They're behind the engines too so no need for dials and such there, just boring riveted panelwork probably... But anyway, is it a really stupid idea having them there? I think it would be passable, I mean anything able to detonate in the engineers compartment will also annihilate the powerplant, cripple the turret and kill most of the crew. With or without fuel in the proximity it's gameover once that area is breached... But is that just me? Can anyone reading this please lend me your opinion on the layout? Would be muchly appreciated!

Further to the fuel tanks, I now have the rads in this kit which I wasn't expecting! (Thanks Mike!) My initial thought was to put them right by the rear of the tank and have a crank driven fan on each engine to assist with cooling. It makes perfect sense from an engineering standpoint but it would block any view of the interior so I'm wondering what other options may exist. Not only for location of the rads but also for adding visibility to this interior once everything is done. I mean like grills and hatches and such so I don't want or expect it to be constantly visible. Then we're back in achilles heel territory!

Working from existing plans limits my choices somewhat but obviously I have that large grill at the back which I'm yet to do anything else to (though still planning a finer mesh grill inside it which would greatly reduce both risk to the vehicle and visibility) And my other known feature of this tank are 2 elongated rectangular sections directly on top of this engineering bay. They look like chequerplate to me but there's no visibility with that! I was wondering about making them grills instead for a bit of ventilation for the engineer and maybe even cooling/intake (as I have intake parts with my kit) I haven't decided where to route the exhausts yet either but that's important as I have smoke and sound to install at a (much) later date!

Further to the chequerplate mention, I need a material for my floor in engineering if anyone has any ideas. I was looking for a sort of steel grate flooring so I could have visible batteries under those hatches at the middle but I'm not decided and either way I can't find anything really suitable! If not then I'll go with chequerplate in which case I need directing to a source for that in 1/16 scale (I know I've seen it in shops before so can't be hard. Worth asking here while I'm posting though!)

Finally a parting word on fuel tanks. I'm thinking I could make some really nice looking ones from real lead which I've used rather successfully lately for a wierd looking floor. It has the perfect colour and texture for an unpainted fueltank and it's easy to mark with grooves (as fueltanks so typically have) or anything else. Here's a shot of my last experiment with the stuff and this is on a 1:100 scale! Again forgive the poor quality...
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I'm not going to dive into any further detail work until I have the turret finished and at least have some feedback so please let me know what you think as everything is easily changed at this point but it soon won't be!
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Munty
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

Wow, please guys, comments one at a time, sheesh...

Ok I don't know where everyone's gone and maybe I'm talking to myself but as long as I'm still working on this project I'm going to keep the worklog going too. So here for anyone out there who's watching from the shadows (come out of there dammit!) is what I got up to yesterday...

I was talking to someone about what I'd been doing and explaining how to date my proudest achievement had been the tracks. Partly because it took quite a bit of work, partly because it's the only thing that looks 'finished' and partly because it actually worked out the way I planned it! Anyway, looking back over old images made me want to carry on with them as I still have 3 more tracks to go sadly... I decided to set to work on the second track and also to pick up where I'd left off with regards to assembling my drive sprockets.

I don't know if I shared the drive arrangement previously but it just so turns out that someone bought a cheap car park playset for my son which he promptly destroyed, leaving me with some nice tubular parts for use in this build! I cut them in half and keyed one flanged end so it locates snugly with one of the sprocket parts I'm using (the drive wheels use 2 faces from my stock but no back) The other end is free and floaty but as this is the drive transfer anyway the whole thing will need major reinforcing at a later date. Here is the assembly as it currently stands...
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Now I've been pondering how to further reinforce this and I'm left with quite a lot of options by the original manufacturers which is nice. I also have to figure out how to attach it to the motor however and that's rather more difficult as it'll be a pretty heavy assembly when finished supporting a LOT of heavy track and pulling a lot of stress... I think I'll need to dismantle the gearboxes and have some custom parts made here which can perform both jobs but we'll see...

First things first, the loose end of the drive sprocket needs securing. The following image shows that the sprocket faces have these circular indentations on either side which go almost all the way through. They provide a perfect location for a reinforcing bar to pass through the black plastic sleeve and then right through the sprocket to prevent movement on one axis. Movement on the other axis is then prevented by the location of the locating lugs so with just this simple fix that end becomes permanently located.
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I think it'll want a bit more than that to reinforce the central part of the assembly which is just plastic however... So my current thoughts are to replace the output shaft of the gearbox with a single piece of metal bar which can pass right through to the outer end of the drive sprocket and then have the short piece of bar pass through that as well. That would give me a watertight assembly I think as there would be no weak points (that I can think of!) Anyway, I'd already got one of these black plastic collars cut before yesterday but I've now done all four which took a surprisingly long time (getting the right length to mate the teeth to the track was a bit tricky!) Here is the piece of track I've already made with 2 full metal sprockets at each end and 3 of the home-made drive sprockets between them!
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I can't help but think it actually looks pretty cool already :D In the final build, only 2 of these wheels will be visible on each track though, the third hidden within the armour...

Anyway that's only part one of my dilemmas from yesterday. The next one arose when I realised that the two types of sprockets I have are actually slightly different sizes (I really could've checked earlier but I'd still have had to deal with it at some point!) This first image shows both types beside each other made into 'show' sprockets (ie. not used for drive...) and the one on the right is the new type I haven't started working with yet and it's slightly too big...
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Now both types of sprocket have identical dimensions when assembled so the problem arises from my stacking them up like this as they seperate into 2 different pieces when compared to the ones I've been working with so far. Here are some piccys to illustrate the differences, the original is always on the left.
Split is lower on the new parts so bottom part is smaller;
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Top part is considerably altered but overall height is identical;
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Underside very similar but new part has lower outer collar (stepped part inside) which causes it to sit higher when stacked;
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Now the problem this causes should be fairly obvious, even if it appears quite slight. It does of course casu the lowest of the three sprockets to sit too far away from the other two, therefore pushing outwards on the track and struggling to locate. If there's one thing I've learnt doing this it's that 1mm matters as much in track building as it does in engine tuning :D

Thankfully there's a very simple solution to this so it's not really a problem. This solution is to close the 1mm gap by removing 1mm of metal, seriously, that simple! Because I don't want to ruin any of these parts (even though I have no intention of breaking this model up when finished I may upgrade tracks one day who knows!) I'll take the necessary material out of the inside of the bottom sprcket (the inside of the old set on which the new set is stacked) Don't worry, it's impossible to understand what I mean without pics and I don't have any as I haven't done it yet! Anyway, point is this will allow the new sprockets to sit an extra 1mm inside the old bottom ones and therefore close the gap. It also leaves the old ones relatively unscathed and fully reuseable as intended in the future if necessary!

On top of my little brainstorming sessions I also spent a little time dismantling the next 148 links of track which needs to be cut'n'shut to form the second of four tracks. Here is my box of goodies which I'm thinking I'll put off for now until I can source some 1mm bar to cut my own track pins from. They simply MUST be one piece connectors and I'm not willing to cut up 300 of the King Tiger ones I have as a temporary solution! So if anyone knows where I can get some 1mm rod or bar (any metal is fine) then please let me know ASAP! Here is the track it's needed for, oh and I need about 22meters of the stuff for all four tracks please! Yeah seriously, 74 links at 74mm wide across four tracks. You do the maths...
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I've also done a little more work on the turret but my god is it giving me grief with all these horrible angles! I cut out the top part to give myself an idea of how the last few pieces need to fit together and while the front looks fien (can probably use my templates there) the back is horrendous and may well be altered slightly. Just don't tell anyone alright?! This is roughly where the top fits anyway but it'll be slanted back slightly so as to be higher at the front and tapered down towards the back. I'm only missing the two side pieces now which need recutting, grr biggest material wastage to date, and the one row of smaller pieces to connect the top to the bottom. Looking on the bright side I can probably use my bad side pieces to provide most of that material so all is not lost. I've actually been really good at controlling offcuts so far and have a very small amount of useable pieces left but a grand total of 3 intact sheets left over! So it's only taken me 6 so far and almost all the big pieces are done, just need to recut the hull top which I kinda bodged ages ago :p
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The final piece of discussion for today has already been mentioned and that's driving the tracks. This time though it's about the motor, not the sprockets... It's rapidly approaching the point at which I need to install the hardware into this beast and that means I need to figure out how and where for everything that needs fitting. There is amble room so that's not a problem and never will be! The 'unique' drive configuration is looking to be a little odd however as the drive wheels are located too high in the model to allow standard gearbox location. Here's my solution...
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Yep, it's upside down! Bear in mind I have to be careful here as I have 4 motors and I have to keep the direction of rotation in check as well as which is left and right for control purposes! What I've done here though is simply taken a right hand gearbox and spun it through 180 degrees so it won't bother the rest of the hardware at all. I'll do the same with the left one (this is the rear track shown above) and just repeat it on the front with the second pair of motors... Each 'pair' will go to it's own board and then both will receive signal from the same controller in order to work both pairs simultaneously. Or at least that's the plan... I'm currently lacking a battery, crystals and a controller but everything else is already in place for movement. I still need turret hardware if anyone has spares.

Anyway back to the physical process of transferring drive from the motor to the sprocket, I took a few images to illustrate the shortcomings I noted earlier. Here is a shot of where the motor will be in relation to the drive sprocket when everything is assembled.
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And here's where it WANTS to be in order to make physical contact with the itside of that first part of the sprocket...
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So you can see there's about a 10mm gap there that I need to fill but just adding an extension onto the end of the current shaft will introduce a massive weakness into the system so I'm in favour of replacing it with a custom made part. I've just dismantled (very carefully!) one of my gearboxes to remove the final drvie shaft for some measurements and to try and figure out what I can do and how I can do it. I just knocked the gear off the shaft a bit and I see the whole assembly is made from one piece of turned rod. That means I'll need to have someone with a workshop make these things for me :(

Anyway time for some rough estimates... Actually, forget rough estimates, I just sacrificed a small portion of my day throwing this together and actually it explains my thoughts rather well. Seems quite logical too so could quite easily be done by someone with a lathe or similar. Let me know if you want to help me!
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It needs to have a total length of about 75mm and a width of 8mm at the fattest point. I'll want a threaded hole in the outermost end which can be used to directly secure and centre the outer sprocket to the shaft and the first 25mm needs to have a width of 5mm so my bearing and gear can be fitted to it. That's it though, it's really that simple!

All it needs is a piece of metal rod to those specifications and a few modifications to drive my mammoth tank (well four pieces obviously) The bearing and gear willfit onto the narrow end which will then be able to be refitted to the gearbox. The outer end will fit first through the centre of one of the sprocket faces (which must be windened to allow for this) and then through the black plastic collar (in green here) and finally butt up against the inside face of the outer sprocket which will be bolted into the shaft. 2 rods will then be passed through the plastic collar, metal sprockets and drive shaft to ensure the entire assembly is completely solid.

Problem solved! Now who wants to make them for me? Please? Consider it an unofficial sponsorship deal lol

Anyway to finish up here's an image I should've posted earlier but it does go some way to show the part of these sprockets which will take both the bolt and the enlarging for the shaft.
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And finally, here is the track formation I've decided on but it's not proportionate... The top left wheel is the drive sprocket avec le tube plastiqe while the other two are full metal assemblies. The right side of the image is the outer edge of each track (ie the front of the front and the back of the back) while the drive sprockets will all be located centrally at the innermost corner of the assemblies. The two standy-uppy things on the left and right are actually spent blanks from my military days but are there to represent the two further points of contact I need to create to finish off this setup. I've pretty much decided I'll just run a metal bar from one side of the track housing to the other and then fit rollers on it for the track to pass over. Not going to bother with a tensioner if I can avoid it but we'll see. At the bottom there will be 4 bogey wheels between the two large metal ones which I'm planning to construct as two cantilevered double bogeys. And yes I'm aware that probably isn't correct terminology as it sounds like a golfing term but what are you going to do hey?!
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So from here on out what do I need... Right.
I need some barrels making for me, 400mm long EXTERNALLY and then whatever else internally (it'll have a firing mechanism fitted). They're 120mm cannons so I guess a 6mm bore isn't too far off (bb size) but the last few inches could probably do with being 7 or 8mm to stop them looking so weedy on such a gigantic tank. The external diameter can be anything up to 30mm at the turret with a taper along the whole length to around 15-20mm at the business end.

I'm also still looking for a suitable material for the floor in the engineering bay so anyone with advice on this sort of material in 1/16 please let me know your thoughts!
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On further searching I just found this stuff which could be easily replicated with an old grill tray and some car grille material... Might do as a second choice...
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I'm in the market for the turret gear I'll be needing too which is one motor for turning and lifting but two for firing...

Also still after a battery or two and one controller with two crystals that'll respond to it in unison!

As for progress... Well I need to re-cut the side pieces for the turret, re-cut the large top piece for the hull (which needs to be removable) cut a final small piece to finish the hull and individually craft the last 14 pieces to attach the turret top. I then need to cut the hole for the turret both in it's own base and in the hull top but thet'll wait till I have the motor for rotation for obvious reasons! Once the turret is finished it'll still be needing it's armament fitting which is not only the twin cannons but also 2 Tusk missile pods which I'll probably kitbash from some airfix planes or something (just a plasticard box with 6 rockets in it!) Then I need to detail the engine bay, reinforce the joins between the hull and the track pieces, brace the main compartment for the hardware, fit the hardware, test the hardware, fabricate new driveshafts, finish the last 3 tracks, alter the sprocket height, get hold of 21meters of 1mm metal rod and cut it into 300 pieces, scratchbuild 16 bogey wheels, deal with suspension, fit the wheels, mount the tracks, detail the armour plating, detail everything else then it might be about done...

Hmm...
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blimp
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by blimp »

8O Blimey Tim , you're not doing things by half are you ! - about those drive shafts , that's a big overhang there , can you redesign it for a bearing on the outer end ? because i can see it just bending or snapping off like a carrot otherwise . . . .
to the bouncy room ! Yay !
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Munty
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

Thanks Blimp I was actually thinking that might be a good/necessary idea. It'd be VERY easy to extend that shaft some more so it goes right through both sprockets and then is seated in the outer side of the track armour as well. The plasticard that's forming the main shell of the build will mostly be covered with the individual armour plating and the tracks are some of the most detailed areas for that so I can essentially cut a hole right the way through the whole tank to make allow for the drive shafts to both enter the carriage (no bearing here as it's right by the gearbox) and also embed itself into the other side of the assembly (which WILL need a bearing) I say bearing but really they're just little brass dishes or something aren't they? Can't be hard to find a couple of them then have whoever I get to make these shafts mill the last few mm down to fit into it... Here's a revised image along those lines.
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Anyway, I've been rather lax again for a few days but I've rectified the situation with the sides of my turret now and it's come out really well. I've also cut the first 3 small pieces which will connect the top of the turret to the rest of the assembly. For these ones I'm using the plans to make a template then just moving straight on to the plasticard. Down the line I think I'll need to alter a few of the pieces as the geometry is a bit evil. That said, the ony parts of the entire build so far which have been made differntly to the plans are the sides... Hmm...

Bah, no piccies yet anyway, I'll put some up when I've finished the turret off though the top piece will not be properly attached as I still need to cut the hole and fit a load of hardware before I seal it up. Maintenance on the turret won't be easy so hopefully nothing breaks once it's finished :D

Anyhow I'm all ready to get started on the 2nd track and I'm pretty fired up to be honest but I want to get hold of some wire first. Blimp seeing as you're the only person here to ask, do you happen to have 21meters of 1mm metal rod lying about the place :D

PS. What do you think about the above pic for a final arrangement for the sprockets and belt? Any thoughts on how I can create the two other 'rollers' I need? I'm thinking a metal bar right through the assembly (like discussed now with the driveshaft) with some free-spinning wheels to help the track roll over it. Simple but should do it I think?
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by blimp »

Yes mate i've a few thoughts on the way you're going with this , I'm a turner myself but am working flat out at the mo , not even time to do my own mods ! - It's well late here in blimpland so i'll get back to you when i get the chance .
  • AS for wire , look up SWG listing in the interweb , (standard wire guage) it will be a machinist reference to wire sizes . RC stockists stock such stuff , often called 'music wire' i buy it in 36" lengths for a squid or so a pop . The nichrome (stainless steel)stuff is best , but hard . brass would be better for workability and as it will be only 'rubbing' against plastic , i'd go for that .
Zzzzzzzz (Hic) . nighty night . B .
to the bouncy room ! Yay !
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Munty
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

Thanks Blimp just having a quick google now... I don't have an accurate measurement of these pins so if anyone else out there has a caliper and some kind tiger tracks I'd really appreciate a decimal figure of the diameter!!! At as best a reading as I can get I think they're just a touch over 1mm so 19 gauge seems like it might do the trick at 1.016 or maybe 18 at 1.219 but having it slightly too small may be rectifiable whereas having it too big will be a complete bust!

I then searched for music wire and immediately found a few good hits but strangely they only give a price, not a length... It all comes coiled but by the sounds of your previous advice that's the sort of thing I want? I was thinkingit would want to be more rigid like the stuff that's already being used (remember it only has 5 points of contact and the track itself has no strength) so I'm wondering if this stuff might be a bit flimsy for what I need, what do you reckon?

Got the nose of the turret finished now (between the cannons) and will be aiming to complete it today with a bit of luck. Then it's just those 2 pieces to finish off the hull top and building the rocket pods for the turret. I think soon it's going to be onto the task of hardware and detailing, still need this wire before hardware can get a road test though...

EDIT : Ebay reveals some interesting hits in 18 gauge, how about this stuff? http://cgi.ebay.co.uk/15x-WHITE-Stem-Fl ... 2026wt_905 It's florists wire (no hits for music wire) but I guess if the diameter is right this stuff looks pretty good... Cheap too :p
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[ICE]monkey
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by [ICE]monkey »

you do like to give yourself a challenge, the car grill floor will look great
regards, ice
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blimp
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by blimp »

Nope , florist wire is soft and flexible , the plastic coating stops it bruising the stems . I just checked some H/L ones with a micrometer - they are 19 swg . try model suppliers , any that do boats , trains + aircraft normally have it . Nichrome may be overkill , standard carbon steel wire is plenty stiff enough . * The best way to 'cut' it is to hold it in flat nosed pliers , as close to the jaws as possible to stop the end getting bent and bend it back and forth , it will then snap off cleanly . Side cutting pliers are rarely man enough for the job . The ends can be sharp and jagged , a cheap bench grinding wheel (+goggles !) makes short work of those . :D
to the bouncy room ! Yay !
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

I'm thrilled to report I've finally managed to meet a personal deadline! The turret is finished in it's entirety and I've got one of the last two hull pieces done too along with a few other tweaks! Be prepared for a pic heavy but also progress heavy update!

Of course I realise now, too late as always, that the last update I posted with piccies was just before the new side panels went on and I don't have any images of the replacement parts but it's only a minor step in the much larger journey of finishing the turret so I still have the majority of it to share!

I was really pretty lost as to how to finish off the last row of the turret as a few test fits of the top piece I cut showed that the angles I had were a bit suspect, it turned out they weren't all that bad after all though. Regardless I decided it would be impossible to finish the turret off properly without attaching the top piece so I'll have to insert the hardware at a later date. I think I'll cut a rectangle out of the bottom piece and then have is screwed into the main turret assembly for easy access to the hardware there. I'm still undecided on how I'll make the final hull piece removable and that's the final piece I have to cut so I really need to get on top of that!

So anyway, I mentioned the angles seeming a bit funky before I got really stuck into the last row of pieces, this is down to the way I went around beginning the job... There are a total of 14 pieces in the top layer and I decided the easiest way to get started would be to fit the front 3 pieces and the single central piece at the rear. So first I did the front three, following the plans exactly for size and shape. This is the final assembly.
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Now I didn't take any pictures of what was causing me all the headaches but basically, the angle of those three pieces made the top part of the turret point way up at the back. It looked totally wrong and very unnatural given the rest of the lines on the turret. Strange thing is it didn't match the plans either but I know the plans are good as they worked fine in the small scale build. Anyway who knows... Suffice to say it gave me a sleepless night before I took another try at tackling it today!

Anyway, I decided to ignore the exact angle of the side pieces at this point and just use the very front piece as a guide to where everything should sit. I knew the end result I wanted like the angle and appearance and such so it was mostly a case of eyeballing at this point with the occasional measurement for good... um, measure... Using a very rough fit of the top piece based on the assembly at the front I decided on the size of the rear piece, using the shape from the original plans. I ended up adding about 10mm to it's length/height, whatever you want to call it, and I think it was a good call as the end result turned out exactly how I wanted it.

Moving on from the rear piece I decided the two long side pieces would be a good bet for the next choice and also decided I would remove the front three pieces while I did these next two so the funky angles wouldn't throw me off as I progressed. In these shots I have all of the above pieces fitted but haven't yet removed the front assembly.
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It seems in the last few hours I've forgotten the exact order of this build process as my images tell me that I fitted the top piece before removing the front! I think the first shot may be test fitted but the second certainly looks glued in place. These side pieces are the first to date with a slight flex in them as the top and bottom edges do not run exactly parallel. Thankfully they're pretty long pieces so it didn't prove too problematic, as the pieces got smaller the same cannot be said however!
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In this shot you can finally see the problem with the angles at the front. I removed these three pieces together after taking this picture.
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This is the assembly finally taking shape with the back and sides in place and the front removed.
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From here on out I tried to tackle the flattest parts first and next on the list were two fairly small pieces at the back. They were made with a mixture of eyeballing, measuring and paper templates and came out pretty well. The new pieces are at either side of this next shot.
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Next I moved round to the front to try and re-attach the 3 pieces already removed there but only the middle one was any good. That said it fitted with no adjustments after I removed it's now useless neigbours so the turret now has six of fourteen pieces fitted!
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After realising the old neighbours of the previously fitted piece were no longer any good I used them as guides for making replacements. I somehow managed to mess it up first time round and I had to discard a third piece from my selection of five before both sides were fitted. In the end it all came out looking pretty tidy though so i was worth a little wastage to achieve the end result!
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The next pieces at the front gave me a little more trouble than I would've liked but that was my own fault. After the amount of filing and sanding I'd already done to get all the chamfers right on the previous pieces I guess I got lazy round about here and after filing not enough and not enough and not enough, I finally took off a bit too much and left about 1mm gap on the left one of these two pieces! I used some extra glue and some of my plastic filings to fill the gap (good tip for those who don't already know it. A bit of poly cement in an open gap and then just run your finger in the filings. Then wipe it onto the glue and due to the nature of the materials it will melt to create a kind of putty ;))
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I didn't take any more pics of the last few pieces after I did them but it makes no difference as these show the same result anyway! This is the finished front, the last two pieces had a slight flex in them like the long sides did but their smaller size exaggerated the issue somewhat here. The first one (on the left) took a lot of fiddling to get looking clean as I secured the whole thing at once which proved difficult due to the flex. The one on the right I fastened one corner at a time (waiting for the first to dry thoroughly before creating the bend and glueing the second)
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The last pieces on the back were similar to the side and front pieces but this time they were essentially long narrow diamonds with a bend near the middle.The plans I'm working from (taken from the 3D model used in game) uses 2 triangular pieces in the places I'm using single flexed pieces but I much prefer the clean look with as few unnecessary lines as possible. With use of a paper template they actually came together pretty well and they were the last pieces needed to finish the turret!
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Here are some shameless glamour shots of the finished product in all her geometric glory!
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A further development after finishing the turret was the mounting of this central crosspiece of the hulltop. I marked and drilled it for the turret's pivot point and I did the same on the bottom of the turret itself.
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For anyone who wants a laugh at my expense I had to put on a quick backpedal at this point and redo something I finished weeeeellll over a month ago! Anyone remember this?
Munty wrote: The following image is amongst my worst yet but you may be able to just make out that the top left piee is too short and the longer right piece (top-side piece not top-top piece) is too long. I removed the left piece and cut about 2mm off the longer piece on the right. This was my first mathematical error and also my first part replacement so far.
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Another duff pictrue showing just how minute the error in calculation was. The fact it's an angle and I'm anal however demands that it be replaced with a slightly larger piece!
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Well it turns out I made a miscalculation on the original hulltop and not on the small piece I replaced (which was perfect first time round!) I discovered today that the corners of my styrene sheet are not perfect right angles so I imagine I cut this large piece from an imperfect corner which caused what appeared to be a perfect edge across the build to actually be slightly angled. Bah...

Long story short, when I came to fit the crosspiece I realised this piece was too long! Yes, it was the perfect size AND shape before I replaced it with a bigger piece... So I had to remove it and make the same piece for a third time! I also had to replace the long straight piece in front of this suspect as I'd shortened it previously to accomodate the new longer replacement I made. Anyway, that's all done now and my drill hole is even the right size to allow a cocktail stick to allow turret rotation :D

Speaking of which, here she is in all her current glory!
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Not sure if anyone's been paying close enough attention to notice but the turret actually sits slightly further back on the hull than I'd originally thought. You'll see I had it placed about an inch further forward in previous shots...

Here's another shot I took to better illustrate the final driveshaft from my current gearboxes.
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And finally, one last headshot of my toothless croc ready to bite, er, gum someone... Really need to find me some cannons :D
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No more serious progress now until I get some material for the engineering detail. That means flooring at the very least. I'll cut the last piece of the hull tomorrow so all the plasticard construction is done then decide what's next. Probably be engine building as that'll take time and doesn't need the rest of the detail in place prior to it happening either... We'll see though, if that florists wire turns out to be a good substitute for track pins (I found some DEAD cheap!) then I'll do those first so I can get on with the hardware.

If anyone feels like doing a little sheet metal work for me, let me know as I've decided on how to mount the gearboxes AND reinforce the main hull in a oner. Just a simple piece of cutting but I don't have the means to do it myself. If I can't find a willing volunteer I'll probably try doing it in wood instead but I'd prefer metal for several reasons.

Time for bed now or I'll never be able to get up and do more of this thing :D Thanks for looking!
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Munty
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Re: Scratchbuilding C&Cs Mammoth Tank

Post by Munty »

Quick update to ask for some advice from some of the many great painters and detailers in our midsts! I've just embarked on the long, slow journey of building and painting the engines and trannies and such. I still don't have a floor so I'm starting with the power plants and as it's been some time since I painted such a highly detailed kit I've started on the nice big flywheel assemblies!

So far I've laid on a nice dark grey with an aerosol I have from my shipbuilding and just this morning I've given it a fairly comprehensive drybrush with a lighter grey. It brings out all the details like boltheads beautifully but it certainly doesn't look anywhere near finished! Now I don't think I really want to go the way of a particularly old engine so I'm not sure what further effects can be added to this part in particular. Anyway I'm taking a few pics of the step by step paint and build but without a decent camera it sadly won't be worth looking at I think.

In the meantime advice is much appreciated! I've found a great source for my track pins which should come out at about £12 for all 21 meters which is nice so this will probably take a back seat while I do the tracks and hardware soon but we'll see. It all needs doing at some point! Still looking for the perfect flooring in the back and I'm now ebaying for a high res webcam (I figure it'll be cheaper than a proper one!) so maybe I'll have some better shots to show later in the project!
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