Sub-Frame spring mounts evolved! | Fuso Canter FG 4x4

[@ExpeditionCamper]

Very nice work! I can t hardly wait to start my project.

[@BruceandKrista]

Thanks! It’s a very long process!

[@contributor7219]

Given you are spring mounting yours along the entire length, you may need to add shock absorbers between the chassis rails and the box subframe so you don't get unpleasant oscillations on certain road conditions. You'll certainly know if you do need to add them as you'll feel it straight away! It's not something you can necessarily cure with spring tension, so just have a contingency plan for adding them if need be. Our Fuso is a short wheelbase truck so its module is solidly mounted at the very rear of the frame but has 'cushyfloats' centre and front. These allow enough flexibility but damp vibration quite well.

[@BruceandKrista]

Great info - hopefully the rear spring tension will be enough to prevent sway - but some shocks or dampers at the front would be fairly straightforward to add. 👍

[@thasebe13]

Keep up the good work buddy... Happy building!!!

[@BruceandKrista]

Thanks man! One day we’ll make it out west!

[@backbeatpat]

Great work. You're rebounding!

[@BruceandKrista]

Did you notice some spring in my step? 🤪

[@backbeatpat]

No, but I thought you were hopping around just fine.@@BruceandKrista

[@gator701]

thanks Bruce

[@BruceandKrista]

Thanks for watching!

[@gator701]

@@BruceandKrista do my spring specs need to be stronger if my habitat is 2000 lbs heavier? And the double spring setup was mounted just in front of the leaf spring brackets on the frame, is that correct?

[@BruceandKrista]

It’s hard to say - I don’t believe it’s just “weight” related, because the weight isn’t sitting on the springs. The springs are allowing the chassis to twist as the suspension moves (which has no relation to the weight of the box). They are also preventing the box from tipping sideways when the truck is on a side slope - which isn’t really related to weight, but would be related to vertical center of gravity. (More weight up high would require more spring tension on the high side to prevent it from tilting). I think it’s really a game of having a setup that you can tune once everything is built - adjusting pre-tension - and even swapping out springs if needed once you start experimenting. My double spring bracket (technically 4 springs) is the furthest back - it’s the stiffest, so it’s just behind the rear leaf spring hanger. The next one forward will be a single rod (two springs) mounted around the front spring hanger.

[@overlandingomar]

As always a great video. I’m a little intrigued about your setup. It’s not quite a rail on rail system, but very similar. I might not be getting it, but is the weight of the box sitting on six points of contact on both the truck chassis and the box subframe? As you mentioned corrosion between them and you were removing the wood. My system is a rail on rail system with 12 mm conveyor belt rubber strip between the chassis rail and box rails.

[@BruceandKrista]

Basically used to be rail on rail, but now the old “rail” is the sub-frame, which rests on 6 spring mounting points (and there will be two more weight bearing but “free moving” points at the very front!). The box sits with its entire weight spread over the entire flat deck (which is the top side of the sub-frame). So, habitat box sits on flat deck, deck is sub-frame, sub frame spring mounted to chassis!

[@M4Nathan007]

Question: If you don't use a subframe with this style composite box and then hit a trail with moderate offroading, what are the consequences? Are the composite panels stiff enough that they might crack? Or the glue would separate things? Or is it just going to limit some chassis flex?

[@BruceandKrista]

Great question - would be concerned of all of those happening - I would be the most concerned with damage to the composite box. If you have it mounted to a rigid sub frame, then potentially you can concentrate all the stress in the center section of the chassis and cause it to crack.

[@backbeatpat]

That is why I trying a soft box and building in allowances for movement.

[@jameelbandar]

What about the gap between the subframe and the main frame? How far should be?

[@BruceandKrista]

The size of the gap only needs to be big enough to prevent water and debris from building up between the two surfaces. If it does - the debris will mechanically grind away at the paint as the sub-frame moves, and the water will get between the paint and the steel and cause corrosion.

[@jgegere]

Trying to follow the electrical issue you found or did not find? Can you link me to a solution video if you recorded it?

[@BruceandKrista]

Not sure which electrical issue you are trying to follow - I’ve had a few! If you the videos view by playlist, you should be able to find the videos following whichever one it was you were watching… kzbin.info/aero/PLy2lw8MIt9lrrMQWY3IPBXYmr2BwNs_DV&si=CMwH8T9CoqpCx6LF

[@jgegere]

@@BruceandKrista ha, I looked through all your videos and the lists you created before I sent the message. :P Ahh this video kzbin.info/www/bejne/mYGqdHxnhsqFjqc&pp=iAQB I thought there was a more direct fix, your resolution is to find a new board.

[@BruceandKrista]

Yeah I haven’t actually replaced it yet - but keeping eye out for a used one. Once I get a used one I’d be more confident opening this one up to see if I can spot anything obvious - but for now I just have a kill switch and a float charger 😎