We all know that the standard Tost wheel brake is ineffective.

Why? well the drum is too small, too thin.

To stop a 400 kg glider from 40kts,
with no other braking, I calculate
very approximately, the steel drum temp. rise is over 400 deg C.

The expansion means that the shoes no longer match the drum;
without this the drum/ hub would get so hot it would ruin the tire.

You do the math.

John Firth

I don't need to do the math. I've done the empirical tests.
On Monday, October 11, 2021 at 10:39:26 AM UTC-7, john firth wrote:
> We all know that the standard Tost wheel brake is ineffective.
>
> Why? well the drum is too small, too thin.
>
> To stop a 400 kg glider from 40kts,
> with no other braking, I calculate
> very approximately, the steel drum temp. rise is over 400 deg C.
>
> The expansion means that the shoes no longer match the drum;
> without this the drum/ hub would get so hot it would ruin the tire.
>
> You do the math.
>
> John Firth

On Monday, October 11, 2021 at 4:12:23 PM UTC-4, jfitch wrote:
> I don't need to do the math. I've done the empirical tests.
> On Monday, October 11, 2021 at 10:39:26 AM UTC-7, john firth wrote:
> > We all know that the standard Tost wheel brake is ineffective.
> >
> > Why? well the drum is too small, too thin.
> >
> > To stop a 400 kg glider from 40kts,
> > with no other braking, I calculate
> > very approximately, the steel drum temp. rise is over 400 deg C.
> >
> > The expansion means that the shoes no longer match the drum;
> > without this the drum/ hub would get so hot it would ruin the tire.
> >
> > You do the math.
> >
> > John Firth

do tell us, what did your tests reveal?
JMF

Are you guys over thinking this?

When I land my glider, my Tost drum brake, which is properly adjusted, will put my glider nose in the grass, if I apply too much brake.

I don't think that I need any more brake.

On Monday, October 11, 2021 at 7:05:33 PM UTC-4, Rakel wrote:
> Are you guys over thinking this?
>
> When I land my glider, my Tost drum brake, which is properly adjusted, will put my glider nose in the grass, if I apply too much brake.
>
> I don't think that I need any more brake.
How many times can you use hard braking before service of the brake? Part of why we call them "toast brakes".
ASW brakes can be used hard for years and still work well.

After a complete rebuild, new linings, arced, drum resurfaced, it will in fact put the glider on the nose. On the first flight. By the 5th flight, acceptable braking if not astonishing. By the 10th flight, a mild retarding force. After a year, just let roll it out. That was on my Pik20D. My current (ASH26Mi) has the Cleveland disc brake and will skid the wheel, has done for 20 years without attention, and I use it reasonably hard.
On Monday, October 11, 2021 at 1:28:03 PM UTC-7, john firth wrote:
> On Monday, October 11, 2021 at 4:12:23 PM UTC-4, jfitch wrote:
> > I don't need to do the math. I've done the empirical tests.
> > On Monday, October 11, 2021 at 10:39:26 AM UTC-7, john firth wrote:
> > > We all know that the standard Tost wheel brake is ineffective.
> > >
> > > Why? well the drum is too small, too thin.
> > >
> > > To stop a 400 kg glider from 40kts,
> > > with no other braking, I calculate
> > > very approximately, the steel drum temp. rise is over 400 deg C.
> > >
> > > The expansion means that the shoes no longer match the drum;
> > > without this the drum/ hub would get so hot it would ruin the tire.
> > >
> > > You do the math.
> > >
> > > John Firth
> do tell us, what did your tests reveal?
> JMF