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OldOfflineMan
01-01-2019, 06:10 PM
I recently bought a used Trypticon and it had both the common critical hip and tail joint issues that plague this otherwise wonderful toy. If left unfixed these issues will result in the joints completely breaking down and render the toy unplayable. There are a number of fixes available on Youtube and on tfw2005.com and I've documented here what I ultimately did to fix these critical issues.

The Trypticon I bought also had issues with the chest door being slightly too small (it doesn't fully lock) and a warped right panel (so the panel doesn't clip shut at the top near the neck), but these are very minor issues that can be fixed at a later date.


Hip Issue:

The issue here is the spring inside the hip ratchet joint is way too long, resulting in excessive force required to compress the spring enough for the ratchet to move (thus allowing the leg to move). The force comes from a thin cross piece in the hip (you'll see what I mean from my quoted video) which is not strong enough to sustain the force, eventually shattering and destroying the joint.

The best video I have found for the description of the problem and how to disassemble the joint is here:

https://www.youtube.com/watch?v=gf_5bS8HXi4

However, it prescribes pre-compressing the spring to fix this problem, but I am not entirely sure it is a long term fix. My reasoning is below:

Most springs follow Hooke's law. Let:
F = force required to compress the spring,
k = spring constant (how stiff the spring is),
x = amount the spring is compressed from its rest position.

Hooke's law states that:
F = kx

So essentially, the amount of force required to compress the spring further increases as the spring is compressed. It also implies there are two ways to reduce the force needed to compress the spring:

1) change the spring characteristics (either change the material or make the wire of the spring thinner), and/or,
2) change the length of the spring.

The solution in the quoted video does neither. It pre-compresses the spring to hold the ratchet in place, but then it still requires that excessive force to compress the spring further to allow the ratchet joint to move. So, I can:

1) Cut the spring (thus reduce "x"),
2) Soften the spring by keeping it over-compressed (thus reduce "k"), and/or
3) Replace the spring with another spring (thus reduce "k").

I didn't want to cut or soften the spring, as it is irreversible. I ended up using scrunched up newspaper/packing paper as a spring. The amount of paper stuffed into that joint controls how stiff that joint is. The joint does need to be a bit stiff or Trypticon won't hold a pose.

I don't recommend using lubricant on the teeth of the ratchet interface as some of the videos suggest, as lubricants have a bad habit of leaking out of an unsealed joint and/or degrading the plastic.


Tail Issue:

This thread describes the problem very well, and its prescribed solution is good in principle:

http://www.tfw2005.com/boards/threads/titans-return-trypticon-tail-fix.1120326/

Two things I would change:

1) Don't use superglue. It is a horrible adhesive for plastic in toys as it easily fractures under the stress. I would follow Gotbot's suggestion in this thread (http://www.cybertron.ca/boards/showthread.php?t=74627) and use Bondic. That stuff is pretty close to plastic welding.

2) When you get to the step where he says "You may well be able to pry out that piece of the assembly but I couldn't so now we resort to spatchcocking our Trypticon and take the body apart to get to that bloody thing", it is not necessary to disassemble the entire Trypticon, just simply poke out the remaining piece of the ratchet joint from the other side.


After doing these critical fixes, Trypticon moves as he's meant to (and I can play with him with ease of mind).

Happy fixing!

Collectingtoys
01-02-2019, 01:06 PM
Thank you OldOffineMan!

This is must appreciated, it's a great way to buy a problem Trypticon at a great price and nurse it back to full health.

wervenom
01-02-2019, 01:35 PM
Pretty sure I have the tail issue. I'll have to check it out but thanks for posting

imfallenangel
01-02-2019, 03:17 PM
Mine broke (the leg/hip) even before I finished putting it together so I simply returned it.

It simply snapped and the leg was free-floating. For something in that price range, I found it crazy that they had such weaknesses in their design.

But good for you and would highly recommend doing such fixes before it actually breaks.

GotBot
01-02-2019, 05:43 PM
First, thanks for the nod and I have used that stuff a few times now to both repair and build up plastic.

Secondly, I have been lucky and not had the issues but your detailed analysis here is a welcome and seemingly more simple fix for both issues. Thanks for sharing and I know this can help so many people.

Landstander
01-02-2019, 09:36 PM
When I got my copy neither of the legs would move, so I did the disassembly and repeated compression of the springs, and that seemed to fix the problem for me.

ngnaw
10-29-2019, 11:07 PM
I have the tail problem!!!! I did the hip fixes with the hour of compressing the springs, that worked.



I have Bondic for the tail fix but would epoxy be better? or Bondic? I'm just concerned that it's a ratchet and never used Bondic on a ratchet joint.

OldOfflineMan
10-30-2019, 08:01 AM
I have the tail problem!!!! I did the hip fixes with the hour of compressing the springs, that worked.

I have Bondic for the tail fix but would epoxy be better? or Bondic? I'm just concerned that it's a ratchet and never used Bondic on a ratchet joint.

You're really not using it on the joint itself, but on non-moving part that forms part of the joint.

Bondic requires quite a bit of prep to use properly (e.g. sloping and roughening surface) and ultimately failed for me after some play as a lot of shear force is applied to the weld surface.

I'd give epoxy a go, but it's gotta be the right type for the plastic.

ngnaw
10-30-2019, 08:12 AM
You're really not using it on the joint itself, but on non-moving part that forms part of the joint.

Bondic requires quite a bit of prep to use properly (e.g. sloping and roughening surface) and ultimately failed for me after some play as a lot of shear force is applied to the weld surface.

I'd give epoxy a go, but it's gotta be the right type for the plastic.I have to open mine up after work. I'm still not getting why it's not grabbing the ratchet. I saw pictures on tfw2005 but he glues that piece on not sure why... Is that part the problem?

OldOfflineMan
10-30-2019, 09:05 AM
I have to open mine up after work. I'm still not getting why it's not grabbing the ratchet. I saw pictures on tfw2005 but he glues that piece on not sure why... Is that part the problem?

Yes. That piece is supposed to be attached to that post, but it is not.

I think you'll understand when you open it up.

wervenom
10-30-2019, 11:46 AM
Damn forgot all about this. have to remember to try it this weekend

evenstaves
10-30-2019, 07:21 PM
I did the fix as soon as I opened him two Xmas's ago, didn't want to take any chances

Used the "working the spring" method instead of clipping it

He was great for me, a good purchase
Full-Tilt is amazing

EDIT - forgot to mention, I made sure my copy was of one those "this lot number is one of the good ones" copies
Don't know how much of anything there was to that, but hey

RNSrobot
10-30-2019, 08:05 PM
Mine broke (the leg/hip) even before I finished putting it together so I simply returned it.

It simply snapped and the leg was free-floating. For something in that price range, I found it crazy that they had such weaknesses in their design.

But good for you and would highly recommend doing such fixes before it actually breaks.

Mm. The hip/tail issues are documented. Sounds like you just got a lemon, as that is a different issue.

I've had two Trypticons with no issues. Good to know about the easy fix if the hip springs grow weak down the road.

ngnaw
10-30-2019, 10:03 PM
I opened him up tonight and managed to fix his tail issue. There is no need to glue the ratchet for the tail, all it needs is a spacer. The reason it warps or breaks the tabs is because of the space left between the ratchet and joint. Hence why one would want to glue it so it doesn't slip down the pivot point. I used a nut as a spacer which keeps the ratchet tight against the tabs. It has nowhere to go now. After doing this and putting him back together you get a nice sounding click and he holds his tail up.