Landships II

MK1 Nut · Hero

3D Printing a MK1 Tank track link

Rob · Legend

Wow, very impressive! The possibilities of 3d printing are very exciting and could mean rare types, accessories etc could be made available that no one would produce otherwise

PDA · Legend

Hi Helen,

Wow. Imagine if Tritton and Wilson had had a 3d printer (and a computer etc).

TinCanTadpole · Legend

Helen, this is fantastic! I've known about the Makerbot for a little while and would love to buy one some day, as I see it as the perfect solution to track links for radio-controlled models (I have 1/16 in mind, perhaps a little smaller, so ABS should do the job nicely).

I understand there also exist 3-D scanners, which would allow you to make a master copy of a track link and scan it in for reproduction, but how expensive such machines are I have no idea.

Re your track link, is the internal part accurate, or have you deliberately changed the design? AFAIK, the track had two separate links attached to each shoe/track-plate - one on each side - with a gap between to allow for the flanges of the rollers to run along in railway-track manner, rather than a single large link stretching across the width. There's a plan somewhere on the forum, I'll try to find the thread and post a link.

TinCanTadpole · Legend

Thread here, post by Roger Todd.

Re-reading Helen's post, perhaps the single wide link is for robustness in a model? A good idea, though if I may, I suggest making a groove in the centre to allow flanged rollers to be used - otherwise lateral forces may make the tracks come off during turns or on side-slopes. In theory, I think the tracks were supposed to be kept in place also by a side rail inside the armour plate (an angle iron/L-beam running along the inside bottom edge of the side armour, next to the rollers and track links), to catch the side flanges of the inner part of the track link (the "rail" of the "railway track" that the rollers rode on) and prevent it from sagging downwards when unsupported crossing a trench. In practice, it doesn't always seem to have worked.

Ironsides · Legend

Hi Helen Great work, a number of things you may consider for metal reproduction..

Rivets are available so not needed to specially make, or have them made in bulk by a rivet manufacturer.

The plates could be stamped and punched �from sheet with a special press tool, a higher cost initially for the tool but likely lower unit price, also stronger.

The main casting may be best done in lostwax bronze but I think the rivet flanges may need beefing up, drill holes with a simple jig as having them cast in could cause problems, casting bronze works better when�not to thick�so avoid really thick areas as the bronze shrinks and pulls the metal from the still molten thick areas on cooling. if you need a specialist bronze caster I have one in mind PM me...

Cheers wink

MK1 Nut · Hero

Hi All, Lots of good replies, that's what I like about this site. xx

Anyhow decorating today... (yeah I know, me with a paint brush! Hows that song go... there could be trouble ahead.) I will be back to do a proper post later tonight. Maybe with a photo of a new improved link with a groove down the middle. :)

Helen x

Paul Bonnett · Hero

Hi Helen, May I ask why you have chosen such a large scale, when surely a scale of either 1/12 or 1/16 would have meant faster production but still with accurate details ?
Paul

MK1 Nut · Hero

Err... ok.. not sure where to start here... so last one first, just to be awkward. :)

The scale of 1/6 wasn't chosen by me, it was more of a group decision. Talking with my friends it was decided that if you're going to do something as iconic as the first Tank to go into battle... then do it BIG! I have to admit, having seen some 1/6 radio control tanks in action, the size and weight of the machines brings a kinda realismto the model.

The Makerbot 3D printer has limitations as far as how small the detail it can render, but its ability to produce objects of shapes I would never have dreamed of... makes all the hassle of set up, worth it. The Track link is a prime example of its use in prototyping, as I have made something, taken advice, and now altering it... normally I would be in tears looking at something that complicated, knowing I have to pull it apart or start from scratch.

The track I've done so far is not I will add at the machines best print level... to impatient.

When it comes to building the track for real, I would agree that things like rivets are just so much easier to purchase. Certainly going to need a lot of them. Eight rivets a track link and about one hundred n eighty of them a tank.� confuse

Same thing with the plates, were quantity means getting it done properly, makes sense monetary and sanity wise.�Casting of the link by a company ablre to produce quality peices in quantity a must, if the tank is to be reliable.

Ok I'm lost now... quick look at what I've said so far...

Oh yeah, I have altered the link and it now has a groove down the middle, not had chance to print it off yet, which is a good thing as I've already thought of a few tweaks.

Which leads me to the 'what if?'

Going on my own experiance Tritton and Wilson would still be playing with the design and the British Tank would have missed the war. :D

Phew! Think that's all of it so far.

Helen x

TinCanTadpole · Legend

You're not wrong about the weight of 1/6 model tanks: I saw an advert today for a 1/6 scale Centurion, weight 110kg/ 17 stone!

CrashandBern · Field Marshal

Wow Helen that's hugely impressive and full credit to you for tackling a project this size.

We have a lot of SLA prototypes made at work (by 3rd parties) and�I'd dearly love to have access to the machines it would save hand making all my masters.

Good luck with the project and keep us posted.

�

Bern

MK1 Nut · Hero

CrashandBern wrote:
Wow Helen that's hugely impressive and full credit to you for tackling a project this size.
We have a lot of SLA prototypes made at work (by 3rd parties) and�I'd dearly love to have access to the machines it would save hand making all my masters.
Good luck with the project and keep us posted.
�
Bern

�Hi Bern,

I must admit, having four brothers who like their techy stuff but lack very often the patience needed to get the stuff working, is very handy... as result I have had hand me downs of ZX81 (yes I am that old) onwards. The Makerbot printer my brother Rae purchased is about �2,000 so I doubt if he's about to let me have it permanently any time soon. But having fun while I do.

This is the version he's using... Makerbot Replicator�not the latest version, but more than good enough for us to play with. I will though admit, even I had a struggle going from 3D images on CAD, to something 'Water tight' that can be used on a Printer.

Helen x

-- Edited by MK1 Nut on Friday 14th of December 2012 11:02:58 PM

TinCanTadpole · Legend

Very nice. Am I seeing curved corners at the bottom of the new groove? Best to have them when you get to a final version, to even out any stresses in this area; a sharp corner would concentrate stresses and increase the likelihood of the part breaking.

Since the planned/hoped-for tank is a group thing (Landships Committee?), do you know what sort of motor(s) is/are intended? Perhaps a large, slow-revving 4-stroke/diesel 4-6 cylinder model IC engine?

About �2000 for the Makerbot? I had a look on their site earlier in the year, and I thought the price was only about $1100 at that time. Even if it was �s, it was certainly not as much as that.

-- Edited by TinCanTadpole on Friday 14th of December 2012 11:10:14 PM

MK1 Nut · Hero

Hi All,

Just a quick update and to prove I listen to you*, I have made a print of the new improved track link.

Now more fiddly looking (scared to use words like 'accurate'), with added slot to avoid sidyways thrust... plus tube bits and bumps for the gear I am working on to grip.

Hope you like

Helen x

�

* Well if you say some thing I agree with that is. :p �

CrashandBern · Field Marshal

TinCanTadpole wrote:
About �2000 for the Makerbot? I had a look on their site earlier in the year, and I thought the price was only about $1100 at that time. Even if it was �s, it was certainly not as much as that.

-- Edited by TinCanTadpole on Friday 14th of December 2012 11:10:14 PM

�They range from around $1,700 to $2,700 by the time you've shipped it and paid duty the �/$ exchange rate is pretty much 1 to 1.�

BLOWHARD · Lieutenant

OH MY HELEN! I'm in love!!!!!! :D :D :D If only I had a set in 1/35 :D

MK1 Nut · Hero

Just a quick update befor eI go out..

Holly flip! these gears are going to be big!!!� confuse

Added a photo of the main drive gear with my head for scale. :) Also a view of my Google Sketchup screen to give you some idea of how messy it can get.

Hmmm... 1/35 scale track... might just give it a go. someone else will have to mould it mind.

Helen x

MK1 Nut · Hero

Hi All, Hope your Christmas went well for you all.

Well I've not had much chance to use the 3D printer recently, so have concentrated on the drawing side of things. I am now drawing the whole backend of the Tank. Madness I know. But it will pay off in the long run, as I have a cunning plan...

Actually it was more a 'YES!' moment. My biggest hurdle to over come when drawing the Tailwheel mechanism, is the fact I am not a draughtsman or engineer, and there for struggle to work out showing a 3D object in 2D. So, I intend to do a 3D tailwheel mechanism on Sketchup first.

Once I know how it all goes together, then I know I will be able to work it into a set of plans. It may also help me with the lack of dimensions available for the tailwheel setup.

At long last feeling positive about finishing my plans at last. :)

Helen x

-- Edited by MK1 Nut on Saturday 29th of December 2012 03:59:04 PM

CrashandBern · Field Marshal

Nice drawings Helen I'm a bit of a dinosaur and still do all my drawing the old fashioned way on a board with a pencil... I'm very envious of people who can use CAD based software as it's so much more flexible.

The engineers at work use SolidWorks...��I think I need to�bend one of their ears and get�a crash course!��

There I have a New Year's resolution!

TinCanTadpole · Legend

Helen, is that an accurate method of transferring drive to the sprocket, or did you change the type of cog that drives the sprocket?

I think I've seen illustrations showing that the full-size tanks (by Mk IV at least - MkI may have been different) had a caged-type gear instead of a normal spur gear; in other words, a gear made up from two parallel discs joined by a series of bars, which engage with the teeth of the sprocket. The discs at the side keep that type of gear from slipping out of mesh with the sprocket if any sideways loads are imposed.

MK1 Nut · Hero

CrashandBern wrote:
Nice drawings Helen I'm a bit of a dinosaur and still do all my drawing the old fashioned way on a board with a pencil... I'm very envious of people who can use CAD based software as it's so much more flexible.
The engineers at work use SolidWorks...��I think I need to�bend one of their ears and get�a crash course!��
There I have a New Year's resolution!

�Yep do it! I must say that I wasn't keen on 3D Cad at first... a certain member on this site did try and get me interested in converting my plans to 3D, I said I would never get the hang of it.... seems I was wrong again. :)

�Must admit though, it did take the carrot of a 3D Printer to get me going.

Helen x

MK1 Nut · Hero

TinCanTadpole wrote:
Helen, is that an accurate method of transferring drive to the sprocket, or did you change the type of cog that drives the sprocket?

I think I've seen illustrations showing that the full-size tanks (by Mk IV at least - MkI may have been different) had a caged-type gear instead of a normal spur gear; in other words, a gear made up from two parallel discs joined by a series of bars, which engage with the teeth of the sprocket. The discs at the side keep that type of gear from slipping out of mesh with the sprocket if any sideways loads are imposed.

�Hiya, Not accurate, no, as compromises have to be made for a working 1/6 scale model.

What I have drawn is though in essence the same drive system used on the actual MK1 tank. The bars on the main gear are just there to keep this large lightweight (ish) gear from warping. This is the latest pictures of the 3D model...

�

TinCanTadpole · Legend

Looks very good - if this model really gets built, it will be very impressive.

MK1 Nut · Hero

With hope the radio control model will happen, but at the very least there will be a 3D model of a MK1 for people to look at on here at the end of it. :)

Work on the 3D plans is crawling along at the moment, although the 3D Printer is now back out from its Xmas/New year hibernation.

A few pics of how it looks now. I want to get the body done, then tail wheel.

Helen x

�

Date: Jan 15, 2013

Where can u get a 3d printer

MK1 Nut · Hero

Finally got around to having a play with the 3D printer tonight, had a go at the track tension adjuster.

The first pic is the adjuster still on the printing bed. For those who don't know the Makerbot printers, they work by building up layers of plastic giving a 3D object which can then be filed, sanded, glued and painted.

On the rear of the machine is a reel of 1.7mm plastic rod, which is heated at the printing head to create a piped icing type effect. This piped molten plastic is printed out into a pattern and then the printing bed moves down a few parts of a mm, and then the whole process begins again. To save weight and platic, you can choose to print with a mesh infill instead of solid. You can also choose the wall thickness, so that a print with little infill can stay strong.

All these options and setting mean it can be a bit of an uphill struggle at first, with more going in the bin than becoming useful parts. The finish is not great, but being ABS plastic it can soon become something acceptable with a little modelling effort.

�

The photos are of the Track Tensioner being printed, it looks a little odd because there's a support grid that gets printed where ever there is overhang. It is clearer what I'm waffling on about in the rest of the photos. :)

Once all the support grid is cut away it becomes clear the job it was performing.

I will clean this one up, sand and paint it... give you an idea of a finished object.

Hel x

TinCanTadpole · Legend

You mentioned in one of your earlier posts, Helen, that the quality was not set to maximum because you had just started experimenting; is this still the case, or is there still the need to sand parts anyway?
It may not be useful for WW1 models, but I think that rippled finish would be great for WW2 modellers wanting a zimmerit effect.

MK1 Nut · Hero

TinCanTadpole wrote:
You mentioned in one of your earlier posts, Helen, that the quality was not set to maximum because you had just started experimenting; is this still the case, or is there still the need to sand parts anyway?
It may not be useful for WW1 models, but I think that rippled finish would be great for WW2 modellers wanting a zimmerit effect.

Yeah the parts will always show how they were built up. I have now cleaned up and painted the track tensioner. Will try and get a photo on here tomorrow.

I do like the idea of using it to show zimmerit, although it only prints like that on horizontal surfaces. You could though make up flat panels and then glue them to a model. Hmmm... might work.�

MK1 Nut · Hero

A few photos of the track adjusters, now sanded and painted. The grey is a primer, so I could sand again and get an even finer finish if I wished. I'm just after a cast item look, like the real thing, so it's good enough for me.

H x

TinCanTadpole · Legend

Looks good, Helen. I like that you've used a paint with sheen, matt paint just wouldn't be right for that date.

Assuming the whole tank gets built at some point, is the intention to use these printed parts as masters for metal castings?

MK1 Nut · Hero

TinCanTadpole wrote:
Looks good, Helen. I like that you've used a paint with sheen, matt paint just wouldn't be right for that date.

Assuming the whole tank gets built at some point, is the intention to use these printed parts as masters for metal castings?

Yep the paint finish was just as I planned!�

Well... umm... err... kinda...

Ok, ok, ok so I didn't stir the paint properly!!!�

It's primer grey, although I have to agree, it looks spot on with the slight sheen to it.�

My plan is to use the 3D printer to make the masters for all the parts I want to get cast in metal. Cad programs are great, but you can't beat something you can hold in your hand. Saves time and increases the chance of getting what you wanted.

H x

MK1 Nut · Hero

A few more parts....

TinCanTadpole · Legend

I remembered last night that "The Guinness Book of Tank Facts and Feats" (by Kenneth Macksey), of which I bought a copy a few weeks ago, has the weight of a track link: 82.15lb each!

At that weight, with 89 links per track, a 1:6 model would have tracks weighing a total of 30.7kg (if made from steel and to the same pattern as the original - it would be a bit more for your inner links, I think). That's 67.7lb or 4 stone 11.7lb for those who prefer imperial weights.

This may be something to bear in mind when selecting the material for casting; of course, you could always take up weightlifting!

MK1 Nut · Hero

It's a frightening thought that the track alone could weigh around 4 or 5 stone... although not unexpected. I have seen a lot of large scale rc tank modelers 'drive' their model into the back of their car/van up ramps. Can't say I blame them. :)

TinCanTadpole · Legend

If you think the tracks are scary, the whole tank at scale weight (divide original weight by the cube of the scale denominator, ie the cube of 6 in this case, which is 216) would be over 20 stone!

GWMA · Private

Hi,

�I've only just discovered the forum an messed up the fisrst message so hopefully this won't be repeated.

Anyway a couple of years ago I completed a modle of the Foster MK1 male tank in fact I built it for a friend who's uncle operated one during the conflict.

The model is a 1/5th scale built from HE30 aluminium and the tracks were 3D printed and subsequently copied...a few times!! I finshed this in 2011 and since then it's been around to a few shows the photo, if I mange to win over the technology, was taken last in Lincoln at the Lincs Life Museum they had a WW1 day at Easter I think it was.

I hope you find it of interest and keep up the very good work.

PJ

�

-- Edited by GWMA on Sunday 3rd of February 2013 08:12:58 PM

MK1 Nut · Hero

Oh god that's lovely!!! Thank you for posting this information.... soooo many questions... first off... Any more photos????

You say the track was 3D printed, did you then cast the track? Would love to see how you solved the issue of track, it's the biggest headache as it is such a key mechanical part which also gives the tank her character..

Helen x

MehdiT · Lieutenant

Hi Helen, you are a real inspiration. I am attempting to build a 3D CAD model of a MK IV as well as a 1/12 scale plastic model. At the moment the plastic model is moving forward faster as I need it to understand better the construction sequence (I am attempting to build the tank using the same construction of the original) before I attempt to assemble in CAD.
I have been lookin at 3D printers for some of the complex shaped parts as the price is getting pretty reasonable now.
I just wanted to ask how long it takes to print a component like the drive gears, guns, rollers and tracks. Also is there much of an odour while printing (ie is my wife likely kick me out of the house into the garage!)
regards
Andrew

MK1 Nut · Hero

Hi Andrew,

Sounds like you have a pretty interesting model on the go there.

Printing times.... ummm... I really should make a note of them.�

From memory, the big blue cog you see me holding above took about two hours. Although large it is mainly spaces and so not a lot of plastic and time involved. The track adjuster took about an hour. I promise to make a note in future.

Yeah, I don't fancy your chances of printing in the house. :)�

Although having said that, you do need to keep an eye on the machine while printing. I'm not being paranoid or anything, but I'm sure it 'knows' when I walk away! I start a print and leave all confident... only to see a spaghetti of plastic where my printed object should be.

As for smell, there's a slight one of burning plastic... you are after all melting plastic onto a hot plate (This helps it stick and not do strange stuff like bow at the corners... grrrr!). It goes as soon as the printing stops and not anything major.�

The noise is more of an issue if it's in the house... think of how popular you would be if you left a normal paper printer running for hours. Not loud, but can get you on edge after a while.�

I think you're heading for the garage, but you may get a repreave if it's cold there, as the printer reallt needs to be warm for good results.

Helen x

MK1 Nut · Hero

Hi All, Not been printing recently, but have been adding to the 3D model for an RC mk1 tank. Playing with a few ideas, my favourite being of a main frame of marine ply, laser cut to slot together. Then a 2mm aluminium metal outer skin, again laser cut, to give her the right look. Fixtures and fittings cast metal.

H x

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