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Armor/AFV: Modern Armor
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Bushmaster PMV - 1/16 experiment.
2805662
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Australian Capital Territory, Australia
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Posted: Saturday, May 16, 2020 - 12:25 PM UTC
Having started to learn CAD at the start of the confinement period in March, I’ve started to draft up a Bushmaster Protected Mobility Vehicle - essentially an Australian MRAP, albeit conceived in the 1990s.

The idea is to print a lot of the structure in PLA plastic, then skin in sheet styrene. This will allow detailing with minimal use of CA.

Here’s the monocoque hull as of this morning. Pretty happy so far.



2805662
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Posted: Saturday, May 16, 2020 - 08:25 PM UTC
My printer is FDM, a process that leaves quite prominent “striations” or layers. For detail work, a mate has a resin printer that produces great results. CAD is mine:



jon_a_its
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Posted: Saturday, May 16, 2020 - 09:51 PM UTC
I'll sit in here, as I spent some time learning CAD, what are you using?

Also consider that your subject is mostly flat plates, & would lend itself to be cut from flat plates & LASERcut from ABS, Acrylic, Styrene, or even brass or steel!

I have sometime access (not right now though) to a laser cutter than can cope with 4 by 8 foot sheet steel up to an inch thick!

Not.jealous.at.all about the resin printer, btw!
Maki
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Croatia Hrvatska
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Posted: Saturday, May 16, 2020 - 10:53 PM UTC
An interesting project! Will keep an eye on this one.

Mario
2805662
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Posted: Saturday, May 16, 2020 - 11:01 PM UTC

Quoted Text

I'll sit in here, as I spent some time learning CAD, what are you using?

Also consider that your subject is mostly flat plates, & would lend itself to be cut from flat plates & LASERcut from ABS, Acrylic, Styrene, or even brass or steel!

I have sometime access (not right now though) to a laser cutter than can cope with 4 by 8 foot sheet steel up to an inch thick!

Not.jealous.at.all about the resin printer, btw!



Not my resin printer, sadly.

I agree about the Ikea flat-pack approach by using cut out styrene. That was my original plan, but the CNC bed on my machine isn’t large enough. There’s a 1,600 watt laser option on the machine, too.

Jealous of your huge laser cutter!

jon_a_its
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Posted: Saturday, May 16, 2020 - 11:57 PM UTC
I work for a uni in the UK,
We have industrial laser cutters & 3D printers capable of printing car bumpers for prototyping....
I don't get to play with the big stuff, hardly st all....

You could send out your flat pack cutting files to a local shop, or do them in sections?
Or print 1:1 for 1/16th on paper & scroll saw cut them, oldschool
2805662
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Posted: Sunday, May 17, 2020 - 04:30 PM UTC
Could definitely be an option.

2805662
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Posted: Monday, May 18, 2020 - 01:20 PM UTC
Test prints of the upper hull identified some issues from transferring CAD to physical. Transitioning from design to production can be a bit of a learning curve.



2805662
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Posted: Tuesday, May 19, 2020 - 02:42 PM UTC
After a bit of rework, I taped together the back 1/4 (125mm) of the hull. Apart from some self-induced print defects, it’s looking pretty good!





Here’s a view of the interior & the asymmetrical cross-section of the lower hull. Also visible is the ‘stringing’ from bad print design on my part, namely omitting print supports.



Cheers.
gibbo
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Posted: Friday, May 22, 2020 - 02:12 AM UTC
Hi Mate,
It's looking good. Big project.

Cheers,

G
2805662
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Posted: Friday, May 22, 2020 - 05:40 AM UTC

Quoted Text

Hi Mate,
It's looking good. Big project.

Cheers,

G



Thanks Mate, appreciated. Yep, lots of work to be done!

Have been working on other parts, such as the antenna bases/mounts:



And test-printed the prototypes..



Started the remote weapon station (known as “PWS” on Australian Bushmasters).



With a low-quality test print to check with some other parts:



More to come.
2805662
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Posted: Sunday, May 24, 2020 - 10:42 AM UTC
More progress on the upper hull. The design has progressed enough to move on to proper prints.

Here’s the slicing software’s visual representation of gcode. Purple bits are support structures that will be removed after printing.



18 hours later:



The support structures are more visible from this angle:

https://i.imgur.com/WZxfqo7.jpg" BORDER="0">

Cheers.



jon_a_its
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Posted: Sunday, May 24, 2020 - 08:13 PM UTC
Looking & good!

Fixed Link
2805662
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Posted: Sunday, May 24, 2020 - 09:16 PM UTC

Quoted Text

Looking & good!

Fixed Link



Thanks!

Moving on...



Which results in this:

2805662
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Posted: Wednesday, May 27, 2020 - 06:30 AM UTC
Finished the print of the upper hull; about 80 hours of printing across the six parts.



The sides & rear will be skinned with 1mm-thick styrene to reduce cleanup.



The reference dimension card is 2cm x 10cm (~.80” x 4”).
2805662
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Posted: Friday, June 05, 2020 - 11:08 PM UTC
Have been busy designing & printing. Getting there.



Which leads to this:



The front end has been the trickiest, noting that I’m only just learning CAD.


2805662
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Posted: Tuesday, June 09, 2020 - 08:59 PM UTC
Making a bit of progress on the front of the hull. Still have to refine the design, but I need to sort how some of the suspension components from Trumpeter’s 1/16 M-ATV will fit onto the Bushmaster.



Mocked everything up to get an overall impression & to give a morale bump.



Looking like the actual vehicle.



deerstalker36
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Posted: Tuesday, June 09, 2020 - 10:33 PM UTC
some awesome work going on here

2805662
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Posted: Wednesday, June 10, 2020 - 10:09 PM UTC
Thanks, Colin. Appreciated.
2805662
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Posted: Tuesday, June 16, 2020 - 05:39 AM UTC
More progress on the fabrication side of the build. I did make a pretty elementary error on the first prints of the engine bay, leaving a .75mm step on either side of the lower hull.

So, took the opportunity to fix the design, plus add some more detail, improve the detail, and make the parts more representative.



The sharp-looking grey coloured print on the left is the wrong one, with the shabby looking grey primer on yellow being the corrected & improved part. Grey old mate is 20 hours of (now wasted) printing, with shabby being 29 hours. Another view:



Changing the print orientation from horizontal to vertical helped with removing the part from the print bed, but introduced additional clean up from having more support material to remove.



This block of cheese is the other side, fresh off the printer. Had to use the distractingly-yellow filament to keep the project moving as it was all I had laying around.



Removing the support structures reveals the part, with some serious clean up required to remove the striations from the printing process.
2805662
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Posted: Friday, June 19, 2020 - 08:56 PM UTC
Figured I should look at the basic geometry of the interior.





Trying a test print at 1/48 to check it out.

HermannB
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Posted: Friday, June 19, 2020 - 09:27 PM UTC
Out of curiousity, what type of printer do you have? I`ve seen several types at Nuremberg Toy Fair a few years ago. Is the printer expensive?
HermannB
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Posted: Friday, June 19, 2020 - 09:58 PM UTC
Speaking of printers, there a company that builds laser metal printers about 15 km away from here.

https://www.youtube.com/watch?v=0xGOFACsFh0

but I think the price of the machine is not for the hobbyist.
HermannB
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Posted: Friday, June 19, 2020 - 10:02 PM UTC
Speaking of prices, a Concept Laser printer is about 235.000 Euros and the machine weights about 2.4 metric tons.
2805662
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Posted: Friday, June 19, 2020 - 10:17 PM UTC
Hey Hans-Herman,

The printer is Snapmaker; it’s also a CNC mill & laser cutter. Good for bigger structures, but not the best for detail. For 1/35, I’d recommend a resin printer.

Cheers.

Greg
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