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MANTIS BUILD part 2
(Again, this my 1st time doing a build thread so any constructive criticism is welcome.)
Edit: Here's the Link to Part 1
If you want to see better Pictures, I have most the same information on a Flickr "Phlog" Album:
https://www.flickr.com/photos/he1mut/albums/72157660113270843
PAINT
Color tests: I used CorelDraw to render different color combos on a trace of the previous progress photo.
Cutout shapes were used for masking on most detail work.
To maintain the assembly markings for the parts, the interior edge of the parts was marked.
I just used latex canned spray paint.
Masking on the abdomen
Stages for the wings; Veins were created by scratching the wet top coats to expose the color of the undercoats :
Everything drying:
Head V2 – Fire and Ice Lights fit perfect into the head housing. The bottom slot holds the cords so no mounting hardware was required.
Atomic age eyeballs! :
TRIAL RUN
All the parts laid out.
Test fit the elbows to the limbs and reestablishes the line markings.
Assemble from the waist down except the longest bottom sections. Run the electrical from the head through the torso, through the “hips”, and down one leg.
NOTE: I hope to figure a smarter way to run the cord next year. Having to having to feed, tighten and pull out the slack of the cord were the upper and lower body meet added sooo many more degrees of difficulty!
So far, so good, stand at about 8ft at this point
This is where the assembly goes South;
I tried assembling everything but the front legs, and then raise it all to attach the legs.
It was just toooo big and unwieldy – swaying, and crashing came next.
A couple of neighbors helped me get it fully assembled, then it did not want to stand!
It kept swaying and tipping forward. As light as the cladding was, those long arms added a lot of leverage induced stress. Everything sagged and swayed. Then one of the rear leg PVC elbows split into pieces. More ginormous crashing.
(Sorry no pictures of any of this, was too “occupied”)
To reduce swaying in all the joints, I put in more screws in the elbows. I removed the arms at the elbows. In an attempt to get things more upright and balanced, I cut the rear legs down another 6-8 inches.
That seemed to do the trick.
BUT – It was leaning forward a lot farther than in the initial skeleton builds and renders. I knew this would put too much stress on the front legs and on the prop in general. Damn you, physics!
I would figure out a fix after tear down. I left it standing for 48 hours and things held up.
Here’s one of the local youngsters pointing at a flaw!
Good catch, buddy! :
Another scale shot with the neighborhood oddball:
I re-marked ALL the meeting points except at the hips where I planned to make adjustments.
ADJUSTMENTS/REFINEMENTS
Some touch up on the paint.
Adjust the angles of the legs at the hip joints to make the prop more upright.
Put some thin plastic water piping over the 9 gauge wire antennae then painted.
FINAL ASSEMBLY.
All the parts waiting to go once again
This time I pre-assembled everything from the waist down and elevated the upper half to take up the cord slack.
Other than dealing with that cord, this assembly was pretty easy.
Being more upright, there was so much less stress on everything, AND I got it back to 12 ft tall.
MONITORING/MAINTENANCE[/SIZE][/B]
I never stopped worrying about something this big failing under one type of stress or another (wind, gravity, etc.) I’d occasionally measure the height to check for sagging, and put a straight edge against the legs to check for warping.
29 DAYS LATER
I had plans to reinforce everything internally and externally if needed, but other than about 8 inches or so of total sagging, and the upper torso turning a bit after wind storms, everything stayed intact!
From the Roof - ready for tear down:
Storage Prep – Most of the limb cladding fit within the torso. I got some clearance felt cloth to protect the paint. It broke down fairly compact. Went trough my attic hatch with no problems.
FINAL NOTES:
As I mentioned earlier, I wish I tried using a heat gun to manipulate the plastic sheet, I might have come up with a more realistic, refined result.
The feet – I didn’t bother talk through these - they’re just zipped on wedges.
The head – I realized all along that it was not a correct mantis head at all. It’s more like an ant head, but heck, mandibles are cool and – it’s a GIANT MUTANT Halloween creature!
Again - Any question or constructive criticism is encouraged.
(Again, this my 1st time doing a build thread so any constructive criticism is welcome.)
Edit: Here's the Link to Part 1
If you want to see better Pictures, I have most the same information on a Flickr "Phlog" Album:
https://www.flickr.com/photos/he1mut/albums/72157660113270843
PAINT
Color tests: I used CorelDraw to render different color combos on a trace of the previous progress photo.

Cutout shapes were used for masking on most detail work.
To maintain the assembly markings for the parts, the interior edge of the parts was marked.
I just used latex canned spray paint.
Masking on the abdomen

Stages for the wings; Veins were created by scratching the wet top coats to expose the color of the undercoats :


Everything drying:

Head V2 – Fire and Ice Lights fit perfect into the head housing. The bottom slot holds the cords so no mounting hardware was required.

Atomic age eyeballs! :

TRIAL RUN
All the parts laid out.
Test fit the elbows to the limbs and reestablishes the line markings.

Assemble from the waist down except the longest bottom sections. Run the electrical from the head through the torso, through the “hips”, and down one leg.
NOTE: I hope to figure a smarter way to run the cord next year. Having to having to feed, tighten and pull out the slack of the cord were the upper and lower body meet added sooo many more degrees of difficulty!

So far, so good, stand at about 8ft at this point

This is where the assembly goes South;
I tried assembling everything but the front legs, and then raise it all to attach the legs.

It was just toooo big and unwieldy – swaying, and crashing came next.
A couple of neighbors helped me get it fully assembled, then it did not want to stand!
It kept swaying and tipping forward. As light as the cladding was, those long arms added a lot of leverage induced stress. Everything sagged and swayed. Then one of the rear leg PVC elbows split into pieces. More ginormous crashing.
(Sorry no pictures of any of this, was too “occupied”)
To reduce swaying in all the joints, I put in more screws in the elbows. I removed the arms at the elbows. In an attempt to get things more upright and balanced, I cut the rear legs down another 6-8 inches.
That seemed to do the trick.
BUT – It was leaning forward a lot farther than in the initial skeleton builds and renders. I knew this would put too much stress on the front legs and on the prop in general. Damn you, physics!
I would figure out a fix after tear down. I left it standing for 48 hours and things held up.
Here’s one of the local youngsters pointing at a flaw!
Good catch, buddy! :

Another scale shot with the neighborhood oddball:

I re-marked ALL the meeting points except at the hips where I planned to make adjustments.
ADJUSTMENTS/REFINEMENTS
Some touch up on the paint.
Adjust the angles of the legs at the hip joints to make the prop more upright.
Put some thin plastic water piping over the 9 gauge wire antennae then painted.
FINAL ASSEMBLY.
All the parts waiting to go once again

This time I pre-assembled everything from the waist down and elevated the upper half to take up the cord slack.


Other than dealing with that cord, this assembly was pretty easy.
Being more upright, there was so much less stress on everything, AND I got it back to 12 ft tall.

MONITORING/MAINTENANCE[/SIZE][/B]
I never stopped worrying about something this big failing under one type of stress or another (wind, gravity, etc.) I’d occasionally measure the height to check for sagging, and put a straight edge against the legs to check for warping.
29 DAYS LATER
I had plans to reinforce everything internally and externally if needed, but other than about 8 inches or so of total sagging, and the upper torso turning a bit after wind storms, everything stayed intact!
From the Roof - ready for tear down:

Storage Prep – Most of the limb cladding fit within the torso. I got some clearance felt cloth to protect the paint. It broke down fairly compact. Went trough my attic hatch with no problems.

FINAL NOTES:
As I mentioned earlier, I wish I tried using a heat gun to manipulate the plastic sheet, I might have come up with a more realistic, refined result.
The feet – I didn’t bother talk through these - they’re just zipped on wedges.
The head – I realized all along that it was not a correct mantis head at all. It’s more like an ant head, but heck, mandibles are cool and – it’s a GIANT MUTANT Halloween creature!
Again - Any question or constructive criticism is encouraged.