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One-sided brake piston?
David Jenkins - 6/5/13 at 07:01 PM

I want to build one of these beasties:



I've got all the bits I need EXCEPT the brake cylinder that goes at the wheel rim. I could hack a 2-sided cylinder, but it would be much easier with a single-sided one.

Can anyone suggest an easily available brake cylinder that would do the job?


Andy S - 6/5/13 at 07:12 PM

Use a clutch slave -

ETA -will you not also need a specific 1" CSA piston to give to a direct reading or are you going to use a correction factor?

Which to save to the calculation is a 1.128" bore

[Edited on 6/5/13 by Andy S]

[Edited on 6/5/13 by Andy S]


britishtrident - 6/5/13 at 07:19 PM

Mini slave but it an adaptor for the piston.


mookaloid - 6/5/13 at 07:20 PM

Classic mini front drum?


britishtrident - 6/5/13 at 07:36 PM

MGB clutch slave might be even better + cheaper.


daviep - 6/5/13 at 07:37 PM

I guess it depends on the pressure rating of the gauge as you want the reading to be to be using a large amount of the scale for best accuracy.

What is the approximate weight of each corner?
What pressure gauge do you have?

Regards
Davie


dave r - 6/5/13 at 08:02 PM

biggest problem, i found with this type of gauge (i have a comercial one, ) is unless you steel wheels, you end up buggering up the rim


David Jenkins - 6/5/13 at 08:08 PM

As for the gauge - I'll have to go and dig in my garage shelves - it's there somewhere! It's a calibrated one reading several hundred psi, so I'm sure the range will be more than sufficient. I'm not bothered about getting an exact measure - as long as I can get a number off the dial I can compare from one side to the other and get the weights balanced across the car.

I borrowed a professionally-made one of these years ago from Rusty Nuts, and it makes the job really easy. I want to do some work on the front end over the next year, so I decided to make one for myself.

dave r - I know what you mean - last time I used one of these I put a small block of very hard rubber between the piston and the wheel rim. Didn't get any damage.


[Edited on 6/5/13 by David Jenkins]


rusty nuts - 6/5/13 at 08:15 PM

Still have mine if you want to borrow it David


britishtrident - 6/5/13 at 09:30 PM

Thinking out the box you could use dial meter type torque wrench instead of a hydraulic load cell.


britishtrident - 6/5/13 at 10:01 PM

Found on ebay LARGE 300Kg 660lb Heavy Duty Parcel Platform Shipping Warehouse Floor Vet Scales | eBay


coyoteboy - 6/5/13 at 10:57 PM

You would need 4 though, not cheap


David Jenkins - 7/5/13 at 01:52 PM

Yep - apart from the slave cylinder, everything will come from the odds and ends lying around my garage, so super-cheap to build! I'm not looking for high sophistication or excessive complication (or high expense).

I'll take a look at those slave cylinders mentioned above - if I can get one cheap off ebay I'll be on a roll.

[Edited on 7/5/13 by David Jenkins]


PSpirine - 7/5/13 at 02:42 PM

Dual cylinder mini brakes use one-sided brake cylinders:

Mini Front Wheel Brake Cylinders LH RH sided pair GWC126 GWC127 for drums | eBay


mark chandler - 7/5/13 at 03:45 PM

Land Rover Series 3 Clutch Slave Cylinder 591231 | eBay

Landrover slave


David Jenkins - 7/5/13 at 03:47 PM

quote:
Originally posted by PSpirine
Dual cylinder mini brakes use one-sided brake cylinders:

Mini Front Wheel Brake Cylinders LH RH sided pair GWC126 GWC127 for drums | eBay


I've just put an ebay order in for something very similar - a single mini brake cylinder. Should do the job nicely!


owelly - 7/5/13 at 04:06 PM

Four Argos bathroom scales at £4 each worked for me!


whitestu - 7/5/13 at 04:07 PM

quote:

Four Argos bathroom scales at £4 each worked for me!



That was my approach as well!

Probably not that accurate but close enough.

Stu