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Delivery-date: Sat, 13 Aug 2022 23:29:41 -0500
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From: DAP AERO <craig@dapaero.com>
Mime-Version: 1.0 (1.0)
Subject: Re: hand car
Message-Id: <21F97698-0560-49C8-A879-CC56C09D360E@dapaero.com>
References: <2c1aa060-0663-76a3-f416-2b5f23f389e4@nctv.com>
In-Reply-To: <2c1aa060-0663-76a3-f416-2b5f23f389e4@nctv.com>
To: Curtis Andrews <andrewscc@nctv.com>
Date: Sat, 13 Aug 2022 21:29:39 -0700

no. I never would have seen that. And I don=E2=80=99t see why it is the solu=
tion =20

> On Aug 13, 2022, at 7:01 PM, Curtis Andrews <andrewscc@nctv.com> wrote:
>=20
> =EF=BB=BFi either figured it out or found a strange coincidence
>=20
> When the crank and connecting rod pivot are not symmetrical there are only=
  a few connection points that will make the rocker arm motion equal above a=
nd below center, and equal motion on both side of the rocker pivot.
>=20
> Our distance from the center of the crank to the center of the rocker arm p=
ivot point is 38" .  using the center of the crank for the center of a circl=
e, draw a 38" radius arc from the rocker pivot.
>=20
> With the rocker arm horizontal, then the connecting rod must be pinned on t=
hat line.  hence the offset.  anyplace else and the motion will not be unifo=
rm.
>=20
> for our configuration, the three offsets that i used are 8 5/8 Horizontal f=
rom rocker pivot shaft,  and 2 1/4 vertical below center of rocker arm. Prod=
ucing 27" stroke at both handles.
>=20
> 11 1/8 horizontal and 3 3/8 " vertical,  for 21" stroke
>=20
> 13 5/8" Horizontal and 4 1/2" vertical.   for 17" stroke
>=20
>=20
>=20
>> On 8/12/22 11:12 pm, DAP AERO wrote:
>> I spent days looking at modeling and could not figure it out. I don=E2=80=
=99t think it is trivial. I couldn=E2=80=99t even finish the equation that g=
ives the position of the pump end of the push rod as a function of the drive=
 gear position.
>>=20
>> This last video has the maximum torque point which I think is when the pu=
sh tod id tangent to the drive gear. But that may not be correct.
>>=20
>> Not sure when I will drive up next, how many windows are there?
>>=20
>>>> On Aug 12, 2022, at 6:35 PM, Curtis Andrews <andrewscc@nctv.com> wrote:=

>>>=20
>>> =EF=BB=BFFor something so simple, i spent hours today and can't figure i=
t out.
>>>=20
>>> i have noticed my mental abilities are deteriorating and this is a test o=
f how bad.
>>>=20
>>> Oddly, my initial offset which was placed based on the size of a scrap p=
iece of steel and where it had existing holes seems to be amazingly close.  t=
he connection simply does not work in many other places, one end of the stro=
ke or the other is off.
>>>=20
>>> Now i am thinking of making the stroke adjustable on the rocker arm so o=
n a down hill movement it moves 21" and uphill it moves 27"   With 24" being=
 the flat track middle stroke.
>>>=20
>>> Have never seen any original ones with adjustable pivot point, so don't k=
now how useful it will be.  But to do that with the same length arm,   has t=
he offset about 2.5 down at 8.5" from center, and 4.5" down at 12" from cent=
er.  I will built a test tomorrow to see if it works.
>>>=20
>>> When are you planning on driving up this way to bring glass?
>>>=20
>>> --=20
>>> Thank You
>>>=20
>>> Curtis Andrews
>>> 1336 E Oak St
>>> Othello WA. 99344
>>> andrewscc@aol.com
>>> 509 346 8108
>>>=20
> --=20
> Thank You
>=20
> Curtis Andrews
> 1336 E Oak St
> Othello WA. 99344
> andrewscc@aol.com
> 509 346 8108
>=20