Foot Fiddle Brakes

[LandyManLuke]

What callipers do you have on the back? We fitted 4 pot callipers which made a massive improvement.

[Team Idris]

Yep, that'd be the popular fix and undoubtedly the good one.

Just want to be sure that I'm close with 3/4" bore CNC brake set, when one fix is the 5/8" set. (283mm^2 vs 197mm^2). I might as well get the most leverage I can, as that is as simple as drilling and filing at this stage.

What did you do to the 2pot brackets to make the 4 pot ones fit? Is the offset from the bracket to the disk the same? Do I only need one more lug?

I see folk with the calliper on top, so I guess they use one old mount lug as fitted, and weld on a second, cut off another axel?

[LandyManLuke]

We made a bolt-on bracket that sits between three extended stub axle bolts and the calliper, based on some original work by SiR.

[RedLineMike]

Only issue with those brackets is they can allow the shock to hit the caliper in some situations

[LandyManLuke]

Yes, shocks can be a problem in some cases. Not a problem with air shocks.

[Diesel_90]

We use the CNC fiddle brakes with 4 pot calipers on our trialer and they work a treat. We have drilled the discs so the pad "bites in" easier. On Saturday one vehicle with the same set up managed to split a 4 pot caliper. It cracked open where the 2 halves are bolted together.

[Team Idris]

The doubt I have in my mind, is rear lock up with 4 pot. Fine for slow off road, but if I'm larking about, do I really want the back locking up at 30mph?

I had a look at a spare rear axel case and I see how a plate would fit to longer bolts. The flange even looks to be in the right place, so thanks for the description Luke. Looks like a job for local laser cutters

[Lewis]

Would you be able to get a second set of brackets cut at the same time? In exchange for some beer tokens of course

I'm local to you

[Team Idris]

Odd though it sounds, I was planning that, as 10 isn't normally twice the cost of 2, as it's the set up that builds the price. I found that with the drop-pin-fairleads. Steel Services at Hixon would be my first ask.

I'll see how I go though first, as my current re-pivoting might fix him?

Maybe it's another thing that should be in the CAD archive anyway?

[Lewis]

Great stuff

[RedLineMike]

Steve, ill do you a swap for a pair of caliper relocation brackets?

[Team Idris]

On the face of it, that does sound a good idea. And I can always sell them to Lewis

But us two crossing paths on the 1.6 tranny does seem to be an issue When are you where?

Or, I could put an axel on the back that already has 4 pot callipers, like another front axel

Better not I guess

[Team Idris]

I set the truck up on axel stands to clean the rear disks with Petrol POWER ! Having 3 lockers makes that much easier, except for a twitchy sensation, due to all the parked vehicles around it

I got at least 70% of the disk clean on the RH rear, which gave me a true idea of what I can achieve in a brake test. Using my left leg I can keep the RH rear wheel locked on concrete, with all the locks open. LH rear isn't as capable, but the disk isn't as well bedded in. So I can expect reasonable performance from my foot operated cutting brakes, and if I need more, I'll get the 5/8" set.

[Team Idris]

Really good

Very pleased with the results in todays trial with Shropshire Off road Club. Much easier to work as hoped, with both hands free to steer.

[simonr]

On old tractors, they used to have a split pedal with a clip that locked the two together for use on the road. Looked just like a single pedal sawn in half!

I experimented a little with this - and wanted push button operation.

First was to use a hydraulic valve which just connected the power steering pump to one pair of pistons on a dual circuit 4 pot caliper, with the foot brake connected to the other two. The pump pressure is almost the same as normal brake pressure (1500psi). This worked very well.

On the next vehicle, I couldn't fit that type of caliper easily so I connected two series clutch master cylinders facing in opposite directions to a pneumatic ram. Connect air to one end of the ram or the other and it presses one of the master cylinders. With 100psi and a 3" bore ram it jammed on the brake 100%.

Food for thought!

Si

[Soren Frimodt]

Is there anything, less spacetravel perhaps, that you have not tried Si? I'm truly amazed at how much time you must have/is spending on experimenting!

[Team Idris]

He is annoying ain't he

He even fitted in some Robot Wars !

I nearly went air-over-hydraulic, or just air-assist on the existing CNC lever set. It was essentially foot vs arm, and I had a spare clutch pedal, (as I left it in place as a foot rest). I even considered it as a single pedal with a throw over valve triggered by the steering being bias left or bias right.

The decider was trial last year where I was fighting to steer and work the fiddle brakes, while my left leg sat on the foot rest! At this point the left-foot-operated-winch-valve idea left the design book and foot fiddles became a priority.

The nice thing over tractor brakes is you can run the front locker a lot, which we do

I would like electric control on the winch levers. Then terry can pay out rope from the remote. I'd like the same system to let me winch in while I change from forward to reverse. But keep my original levers, so I can creep rope in or out. I think this might be the next 'idea' after the current repairs Maybe a wiper motor?