Trimmed M5A1 Stuart

[MonsieurTox]

I see what you are talking about now! I will probably start with weight like E-brute mentioned and I'd like to take some spring out of the rear idler (soft front/stiff rear).

Yeah when you see the side skirts+the high suspensions stance, the Coolbank looks very massive when viewed from the side

If you can get it lower it will look perfect, I hope the extra weight will work!

[Ecam]

Before anyone asks... I have no idea where this spring came from. I tend to keep certain parts in containers for use in tanking. The original spring was about 3 inches (7.5 cm) in length before I cut it down. I used a trigger pull gauge to measure the stock springs against the new. 400 grams (14 oz) original and down to just less than 200 g (6oz) with the replacements. The stock Stuart kit reminded me of a 60s American muscle car, heavy big block up front on relatively soft springs and massive stiff leaf springs to control axle wrap in the back. Over a speed bump, you got a Caddy like ride from the front and an unloaded one ton truck from the rear.

The installed spring and the bottom spring near the idler are the ones that came with the kit. The upper spring near the idler (and the one top right) are the pieces/parts I cut from the 3" spring. Those two on the lower right are from ball point pens.

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[ColemanCollector]

Interesting modification!
How'd you get the pin out that the idler assembly pivots on? I'm assuming progressively less gentle taps with a hammer and drift? Mine looks like it has a bit of glue on it that I'll need to break the grip of. My idler assembly isn't pivoting properly on one side so time to investigate.
Thanks,
Mike.

[Ecam]

Stuck a screwdriver against the pin on the inside of the hull and gradually added pressure, both sides went "pop". No damage. Gentle taps with a brass hammer to install.

Side note, I think Mr Tox is correct in trimming the springs in the bogies. Adding a significant amount of weight to lower the ride height may be detrimental to the gearbox and tracks. And I still think my lesser spring rate on the idler is still too much! Will do some adjustments and report on the results.

[Ecam]

It is going to take someone smarter and braver than me to figure out how to get the bogie springs out of the Stuart. The outer part of the bogies are moulded onto the hull. I flexed one as far as I dared but could not free the spring assembly. Any more flexing and I fear a "snap" is next. So I'm going with a little of both methods. I did trim the Idler spings I installed yesterday an additional coil and a half. Down to 100 grams (3.5 oz) in spring rate. Then 550 grams (19.4 oz) of additional weight and I think the suspension is reasonably compressed.

I did not use the tripod in testing, it was only for the picture.

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And finally, those of you who have this kit, did your left rear fuel cover (smoker fill port) come installed on your tank? I went through the packaging several times and mine was MIA. Decided to make a replacement.

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[ColemanCollector]

Hi Eric,
On my tank the fuel cover was installed, and a real thumbnail bender to open!

I removed the suspension arms by removing the pivot screw (1) and then pulling out the pin (2) that moves up and down in the slot. That releases everything for work. Fun to put back together!

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Mike.

[Ecam]

Thank you. I pushed and pulled on that pin at first but it didn't budge. I'm building lead boxes now and want to see how the additional weight makes the tank ride. I may come back and pull the weights and go back to trimming springs in the future.

[Ecam]

Rear box

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Front box

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Side boxes with front and rear installed. That space in the left side box is for a rib (in the upper hull) that runs to the turret (turn) servo mount.

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With battery onboard as well. Spring rate at 200 grams (per side) was too stiff - 100 G too soft. Goldielocks will try for 150 grams next.

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[MonsieurTox]

Great job Eric, it looks fantastic with the lower suspension, I hope the extra weight won't be too hard on the gearboxes, can't wait to see a vid of it runing with the softer spring in the idler !

[Ecam]

And Goldie said "just right".

Trimmed down those retractable ball point pen springs. Snuck up on 150 grams and the Stuart sits at the height I was hoping for. Just setting the tank down, idlers and bogies all compress a bit.

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