View Full Version : ASK-21 and Grob 103 cockpit ballast weights
kirk.stant
January 3rd 12, 03:34 PM
Our club (St Louis Soaring Association) is looking for a set of
factory ASK-21 ballast weights, the triangular lead plates with a long
pin that screws into a fitting under the pilots knees. We recently
acquired an older ASK-21 and it didn't come with any.
Ditto a set of the factory Grob 103 ballast weights - the triangular
yellow pig iron plates that are fitted under the pilots left knee, and
come in a set of 2, I seem to recall.
If anyone knows of any lying around, please contact me.
TIA,
Kirk
66
Bill D
January 3rd 12, 06:14 PM
This is not a direct answer but still possibly useful to you.
The ASK-21 weights are lead slabs about 12mm thick each representing
2.76 Lbs of pilot weight. This increment is too small and would be
more convenient if larger - say, 10 - 15 Lbs. The bolt which holds
the weights in place is very long with fine threads requiring many
turns to tighten it. Flying with CAP cadets and seniors means weights
are frequently changed which has turned out to be a hassle.
I'm considering casting new, larger 15 Lb pilot-equivalent weights
with a captive bolt of the proper length and a large knob for easy
tightening. These could be swapped out with minimal fuss between
flights. A pair of these new weights would be about right for
teenagers. Grob weights can be made the same way.
If you don't have the tools, you can rent a plumbers lead pot and make
simple molds from plaster of Paris.
Bill D
On Jan 3, 8:34*am, "kirk.stant" > wrote:
> Our club (St Louis Soaring Association) is looking for a set of
> factory ASK-21 ballast weights, the triangular lead plates with a long
> pin that screws into a fitting under the pilots knees. We recently
> acquired an older ASK-21 and it didn't come with any.
>
> Ditto a set of the factory Grob 103 ballast weights - the triangular
> yellow pig iron plates that are fitted under the pilots left knee, and
> come in a set of 2, I seem to recall.
>
> If anyone knows of any lying around, please contact me.
>
> TIA,
>
> Kirk
> 66
kirk.stant
January 3rd 12, 07:24 PM
On Jan 3, 12:14*pm, Bill D > wrote:
> This is not a direct answer but still possibly useful to you.
>
> The ASK-21 weights are lead slabs about 12mm thick each representing
> 2.76 Lbs of pilot weight. *This increment is too small and would be
> more convenient if larger *- say, 10 - 15 Lbs. *The bolt which holds
> the weights in place is very long with fine threads requiring many
> turns to tighten it. *Flying with CAP cadets and seniors means weights
> are frequently changed which has turned out to be a hassle.
>
> I'm considering casting new, larger 15 Lb pilot-equivalent weights
> with a captive bolt of the proper length and a large knob for easy
> tightening. *These could be swapped out with minimal fuss between
> flights. *A pair of these new weights would be about right for
> teenagers. *Grob weights can be made the same way.
>
> If you don't have the tools, you can rent a plumbers lead pot and make
> simple molds from plaster of Paris.
>
> Bill D
Bill, thanks for the input. I'm familiar with the ASK weights and
what a PITA they can be - having done numerous commercial rides with
them. If I can't find any, I'll probably get back to you!
The problem is that right now we are using shot bags - scary!.
Fortunately no acro yet, but I'm trying to get that started and we
will definitely need secure weights then.
Cheers
Kirk
66
flymaule
January 3rd 12, 08:18 PM
We often fly with young folks too light for even the weights. We add
custom made seat weights below their seat cushons (they are always
short as well). Simply cut heavy canvas to the pattern of the seat.
Then compartmentaize it with longtitudinal stitching. Next add the
lead shot weight. Finally sew the end. REMEMBER TO DOUBLE STITCH!!
Our G-103 weights are usually 20 pounds. Weigh them and mark. Under
even a light weight cushion you will not feel them.
Skip
Tony V
January 3rd 12, 11:55 PM
On 1/3/2012 3:18 PM, flymaule wrote:
> We often fly with young folks too light for even the weights. We add
> custom made seat weights below their seat cushons
We give them a scuba diver weight belt.
Tony
T[_2_]
January 4th 12, 01:54 AM
On Jan 3, 10:14*am, Bill D > wrote:
> This is not a direct answer but still possibly useful to you.
>
> The ASK-21 weights are lead slabs about 12mm thick each representing
> 2.76 Lbs of pilot weight. *This increment is too small and would be
> more convenient if larger *- say, 10 - 15 Lbs. *The bolt which holds
> the weights in place is very long with fine threads requiring many
> turns to tighten it. *Flying with CAP cadets and seniors means weights
> are frequently changed which has turned out to be a hassle.
>
> I'm considering casting new, larger 15 Lb pilot-equivalent weights
> with a captive bolt of the proper length and a large knob for easy
> tightening. *These could be swapped out with minimal fuss between
> flights. *A pair of these new weights would be about right for
> teenagers. *Grob weights can be made the same way.
>
> If you don't have the tools, you can rent a plumbers lead pot and make
> simple molds from plaster of Paris.
>
> Bill D
>
> On Jan 3, 8:34*am, "kirk.stant" > wrote:
>
>
>
>
>
>
>
> > Our club (St Louis Soaring Association) is looking for a set of
> > factory ASK-21 ballast weights, the triangular lead plates with a long
> > pin that screws into a fitting under the pilots knees. We recently
> > acquired an older ASK-21 and it didn't come with any.
>
> > Ditto a set of the factory Grob 103 ballast weights - the triangular
> > yellow pig iron plates that are fitted under the pilots left knee, and
> > come in a set of 2, I seem to recall.
>
> > If anyone knows of any lying around, please contact me.
>
> > TIA,
>
> > Kirk
> > 66
Designing new ballast weights and attach methods for the ASK-21 could
get tricky. If the glider is in the Std Category and not experimental,
you would be changing approved design from the original aircraft. New
337s may be required and approved by local FSDO with appropriate
changes to the glider manual.
We have a Grob 103 with the big ballast weights and sometimes that is
not enough. A member melted down a lot of used auto wheel balance
weights into a flat plate about 1/4 - 3/8 inch thick and about the
size of the Grob seat. Place it in the seat, add a cushion. I forget
it's weight but it is 10-15lbs.
T
Burt Compton - Marfa
January 4th 12, 03:03 AM
If it is just a ride then you might consider putting the lightweight
passenger in the back seat.
Actually after giving rides for over 40 years, I recently realized
that non-pilot passengers of all weights tend to be more comfortable
back there . . . and sitting in front I can see the towplane signals,
slack rope, dust devils, air traffic, read the sky, twiddle the radio,
transponder, varios much better in my ASK-13, ASK-21 or DG-1000.
If it is a student glider pilot then a parachute helps and that's a
"legal" ballast addition . . . if the chute has been repacked recently
by the regulations. (Insert your country's repack rules here.)
Just be sure to teach light weight students to install the factory
ballast weights themselves at preflight during their flight
instruction and how absolutely essential it will be before every solo
flight. (Law of Primacy and that "first things they learn" concept.)
Burt
Marfa, Texas USA
Are you sure?
January 4th 12, 03:04 AM
On Jan 3, 2:24*pm, "kirk.stant" > wrote:
> On Jan 3, 12:14*pm, Bill D > wrote:
>
>
>
>
>
>
>
>
>
> > This is not a direct answer but still possibly useful to you.
>
> > The ASK-21 weights are lead slabs about 12mm thick each representing
> > 2.76 Lbs of pilot weight. *This increment is too small and would be
> > more convenient if larger *- say, 10 - 15 Lbs. *The bolt which holds
> > the weights in place is very long with fine threads requiring many
> > turns to tighten it. *Flying with CAP cadets and seniors means weights
> > are frequently changed which has turned out to be a hassle.
>
> > I'm considering casting new, larger 15 Lb pilot-equivalent weights
> > with a captive bolt of the proper length and a large knob for easy
> > tightening. *These could be swapped out with minimal fuss between
> > flights. *A pair of these new weights would be about right for
> > teenagers. *Grob weights can be made the same way.
>
> > If you don't have the tools, you can rent a plumbers lead pot and make
> > simple molds from plaster of Paris.
>
> > Bill D
>
> Bill, thanks for the input. *I'm familiar with the ASK weights and
> what a PITA they can be - having done numerous commercial rides with
> them. *If I can't find any, I'll probably get back to you!
>
> The problem is that right now we are using shot bags - scary!.
> Fortunately no acro yet, but I'm trying to get that started and we
> will definitely need secure weights then.
>
> Cheers
>
> Kirk
> 66
Flying with loose weights or a scuba belt is scary; imagine what will
happen in a crash. Loose weights or a scuba belt will make any crash
even worse.
Our club was in the same situation a few years back. We had two ASK
21s and we had lost all but one of the factory weights and we gained a
new member who was 112 pounds.
I cast two 13.5 pound weights for each ASK 21 to replace the 12
original factory weights. The description of how to do it sounds far
worse than it actually was.
I first used our one remaining factory weight to make a wood replica
that was the shape and size of the intended new 13.5 weights. I then
shaped a band of 2” copper flashing around the wooden form and screwed
the ends together with #6 screws. I then unscrewed them, removed the
wooden form, and screwed the ends together again. This copper form
will become the mold and final outer surface of the weight.
I then set this copper band on a sheet of heavy duty aluminum foil,
and folded the foil up the sides of the copper so it looked like a
bowl the shape of the intended weight.
To create a bolt-hole, I used a copper 1/2” pipe that is 2 1/8” long.
To keep the pipe upright during the casting, I drilled a 1/2” hole
1/8” deep in a board using a forsner bit. I put this board in the
bottom of a pail. I positioned the copper/aluminum form over the
board so that the hole would be in the proper place. I then pushed
the copper pipe through the aluminum into the 1/8” deep hole. I then
carefully poured sand around the outside of the copper form.
I then poured the molten lead into the copper form. The outer copper
sheet and the copper pipe remain and become part of the final product.
The board will get charred with each casting, but I cast 4 weights
using one board.
The aluminum foil is VERY important. I first thought I could do a
sand casting and the copper would hold the sand back while I did the
pouring. Well, the molten lead flowed under the copper band, into the
sand and I had a real mess after that. The aluminum foil creates a
bowl that prevents the lead from flowing out into the sand.
The bolts are 8mm x 160mm. They can be purchased at www.mcmaster.com
I made a large wooden knob over the hex bolt head for easy turning.
You might come up with your own idea on what is the easiest for your
talents.
Then, the most important part: I made two boxes to hold the weights.
That way the weights have a "home" for storage. Without the boxes, it
is very tempting to lay the weights on the ground where they are
removed between flights. That is how we lost the original factory
weights.
If you want photos, let me know.
Are you sure?
January 5th 12, 03:40 PM
On Jan 3, 2:24*pm, "kirk.stant" > wrote:
> On Jan 3, 12:14*pm, Bill D > wrote:
>
>
>
>
>
>
>
>
>
> > This is not a direct answer but still possibly useful to you.
>
> > The ASK-21 weights are lead slabs about 12mm thick each representing
> > 2.76 Lbs of pilot weight. *This increment is too small and would be
> > more convenient if larger *- say, 10 - 15 Lbs. *The bolt which holds
> > the weights in place is very long with fine threads requiring many
> > turns to tighten it. *Flying with CAP cadets and seniors means weights
> > are frequently changed which has turned out to be a hassle.
>
> > I'm considering casting new, larger 15 Lb pilot-equivalent weights
> > with a captive bolt of the proper length and a large knob for easy
> > tightening. *These could be swapped out with minimal fuss between
> > flights. *A pair of these new weights would be about right for
> > teenagers. *Grob weights can be made the same way.
>
> > If you don't have the tools, you can rent a plumbers lead pot and make
> > simple molds from plaster of Paris.
>
> > Bill D
>
> Bill, thanks for the input. *I'm familiar with the ASK weights and
> what a PITA they can be - having done numerous commercial rides with
> them. *If I can't find any, I'll probably get back to you!
>
> The problem is that right now we are using shot bags - scary!.
> Fortunately no acro yet, but I'm trying to get that started and we
> will definitely need secure weights then.
>
> Cheers
>
> Kirk
> 66
One other note about the weights. Kirk.stant stated that each factory
weight represented 2.76 pounds of pilot weight. That is correct and
is stated in the POH. Each factory weight weighs 2.25 pounds, but
since it is forward of the Pilot's center of mass (moment arm), it
will be equal to 2.76 pounds of pilot weight. Hence, each of your two
new weights that you cast should be 13.5 pounds.
Bill[_20_]
January 5th 12, 08:10 PM
I do have a spare set of Factory original weights for a Grob 103.
Any offers?
bill palmer
January 16th 12, 06:10 AM
Kirk,
Try posting a Wanted ad on Glidersource.com for your ASK21 weights.
kirk.stant
January 16th 12, 03:08 PM
On Jan 16, 12:10*am, Bill Palmer > wrote:
> Kirk,
>
> Try posting a Wanted ad on Glidersource.com for your ASK21 weights.
Bill, thanks, I'll try that.
Kirk
September 2nd 15, 08:57 PM
On Thursday, January 5, 2012 at 1:10:28 PM UTC-7, Bill wrote:
> I do have a spare set of Factory original weights for a Grob 103.
> Any offers?
I am interested in the weights if you still have them?
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