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>
> Dave: Thank you for your thoughtfull reply! The groove in the main
> shaft that locates the split collars is not as bad as it looks - most of
> the taper turns out to be material worn off of the split collars and welded
> onto the main shaft. I have cleaned up the groove, to the same dimesion as
> the groove on the new main shaft I bought (that has the oversize issues)
> and that took out all the taper.
> The concern I still have is *how to prevent the split collars from
> spinning in the future* to prevent this from happening again - either on
> the old shaft or on a new shaft. The split collars are not bearings or
> bushings and if they keep spinning in the future I'll see the same problem.
>
>
>
>
> From: DAVID MASSEY <dave1massey@cs.com>
> To: "aribertn@gmail.com" <aribertn@gmail.com>, "triumphs@autox.team.net" <
> triumphs@autox.team.net>
> Cc:
> Bcc:
> Date: Mon, 20 Mar 2023 12:39:48 +0000 (UTC)
> Subject: Re: [TR] Calling anyone with transmission rebuilding experience -
> second attempt, part 1
> It has been many years (< 25, I think) but I once rebuilt a TR6
> transmission with a used mainshaft that had similar wear on a shoulder like
> that. There was a thrust washer that fitted up against shoulder. A few
> years later I was rebuilding it again. The thrust washer had broken into
> parts. My solution was to buy a new mainshaft (that is a story in itself)
> along with some other parts. 25 years later that part is still soldering
> on. (I had to rebuild again for layshaft issues but that's unrelated)
>
> I would be very reluctant to reuse that mainshaft. The raised ridge is
> not what worries me it is the fact that the edge of the grove is not square
> and the thrust applied by the helical gears will point load the split
> collars and they will fail again. The TR6 transmission si probably
> different but the basic design is similar and the force loading is also
> similar. Helical gears are sued to keep tooth noise down but the fact that
> they are wound in a helical manner around the axis means the forces applied
> to the gears is at an angle to that axis. Part of that force is used to
> rotate the shaft but the other is applied to the bearings at either end of
> the transmission meaning the split collars in your case will take up that
> force as an interface between the shaft and the bearing inner race. I
> don't have enough experience to say whether the transmission will last a
> week, month, year or 10 years with that shaft but I would have much more
> confidence in a new, quality shaft.
>
> Dave
>
>
>
>
>
>
>
>
>
>
>
> ---------- Forwarded message ----------
> From: DAVID MASSEY <dave1massey@cs.com>
> To: "aribertn@gmail.com" <aribertn@gmail.com>, "triumphs@autox.team.net" <
> triumphs@autox.team.net>
> Cc:
> Bcc:
> Date: Mon, 20 Mar 2023 13:30:54 +0000 (UTC)
> Subject: Re: [TR] Calling anyone with transmission rebuilding experience -
> 2nd attempt, part2
> That looks like the heat treated, hardened surface is starting to break
> up. That is what happened to my layshaft. Another reason to abandon that
> mainshaft. If you have an alternate bearing combination that doesn't relay
> on that surface for the bearing rollers then the hardened surface is no
> longer critical. But this is above my pay grade.
>
> BTW, I misinterpreted one of your previous photos. The split washers
> transfer the lateral forces from the synchro hub to the mainshaft but the
> end result is the same, with a compromised groove surface like that the
> split collars will fail prematurely. If you open the grove to clean up
> the shoulder will the split washers stay in place? If they fall out you
> have serious problems. Even if they stay in place will it increase
> backlash? Can you get oversized split collars? Make shims? All this is
> above my pay grade.
>
> Dave
>
>
>
>
>
>
>
>
>
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<div dir=3D"ltr"><div class=3D"gmail_quote"><blockquote class=3D"gmail_quot=
e" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204)=
;padding-left:1ex">Dave:=C2=A0 =C2=A0Thank you for your thoughtfull reply!=
=C2=A0 =C2=A0The groove in the main shaft that locates the split collars is=
not as bad as it looks - most of the taper turns out to be material worn o=
ff of the split collars and welded onto the main shaft.=C2=A0 I have cleane=
d up the groove, to the same dimesion as the groove on the new main shaft I=
bought (that has the oversize issues) and that took out all the taper.=C2=
=A0 </blockquote><div>=C2=A0<br></div><blockquote class=3D"gmail_quote" sty=
le=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);paddi=
ng-left:1ex">The concern I still have is=C2=A0<b>how to prevent the split c=
ollars from spinning in the future</b>=C2=A0to prevent this from happening =
again - either on the old shaft or on a new shaft.=C2=A0 =C2=A0The split co=
llars are not bearings or bushings and if they keep spinning in the future =
I'll see the same problem.<br><br>=C2=A0 =C2=A0=C2=A0<br><br><br>From:=
=C2=A0DAVID MASSEY <<a href=3D"mailto:dave1massey@cs.com"; target=3D"_bla=
nk">dave1massey@cs.com</a>><br>To:=C2=A0"<a href=3D"mailto:aribertn=
@gmail.com" target=3D"_blank">aribertn@gmail.com</a>" <<a href=3D"m=
ailto:aribertn@gmail.com" target=3D"_blank">aribertn@gmail.com</a>>, &qu=
ot;<a href=3D"mailto:triumphs@autox.team.net"; target=3D"_blank">triumphs@au=
tox.team.net</a>" <<a href=3D"mailto:triumphs@autox.team.net"; targe=
t=3D"_blank">triumphs@autox.team.net</a>><br>Cc:=C2=A0<br>Bcc:=C2=A0<br>=
Date:=C2=A0Mon, 20 Mar 2023 12:39:48 +0000 (UTC)<br>Subject:=C2=A0Re: [TR] =
Calling anyone with transmission rebuilding experience - second attempt, pa=
rt 1<br>
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div> <font size=3D"3">It has been many years (< 25, I think) but I once=
rebuilt a TR6 transmission with a used mainshaft that had similar wear on =
a shoulder like that.=C2=A0 There was a thrust washer that fitted up agains=
t shoulder.=C2=A0 A few years later I was rebuilding it again.=C2=A0 The th=
rust washer had broken into parts.=C2=A0 My solution was to buy a new mains=
haft (that is a story in itself) along with some other parts.=C2=A0 25 year=
s later that part is still soldering on.=C2=A0 (I had to rebuild again for =
layshaft issues but that's unrelated)</font></div>
<div><font size=3D"3"><br>
</font></div>
<div><font size=3D"3">I would be very reluctant to reuse that mainshaft.=C2=
=A0 The raised ridge is not what worries me it is the fact that the edge of=
the grove is not square and the thrust applied by the helical gears will p=
oint load the split collars and they will fail again.=C2=A0 The TR6 transmi=
ssion si probably different but the basic design is similar and the force l=
oading is also similar.=C2=A0 Helical gears are sued to keep tooth noise do=
wn but the fact that they are wound in a helical manner around the axis mea=
ns the forces applied to the gears is at an angle to that axis.=C2=A0 Part =
of that force is used to rotate the shaft but the other is applied to the b=
earings at either end of the transmission meaning the split collars in your=
case will take up that force as an interface between the shaft and the bea=
ring inner race.=C2=A0 I don't have enough experience to say whether th=
e transmission will last a week, month, year or 10 years with that shaft bu=
t I would have much more confidence in a new, quality shaft.<br>
</font></div>
<div> <br>
</div>
<div style=3D"clear:both">
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div><font size=3D"4">Dave <br>
</font></div>
<div><span style=3D"font-size:10pt;font-family:sans-serif;color:black"><br>
</span></div>
<br>
</div>
</div>
</div>
<div> <br>
</div>
<div> <br>
</div>
<div style=3D"font-family:arial,helvetica;font-size:10pt;color:black"><font=
size=3D"2"><div id=3D"m_6593041711186351867yiv0386429821"><div dir=3D"ltr"=
><div><br>
<div dir=3D"ltr"><div><br>
</div>
<div><br></div>
<div><br>
</div>
<div><br>
</div>
</div>
</div>
</div>
</div></font></div></div><br><br>---------- Forwarded message ----------<br=
>From:=C2=A0DAVID MASSEY <<a href=3D"mailto:dave1massey@cs.com"; target=
=3D"_blank">dave1massey@cs.com</a>><br>To:=C2=A0"<a href=3D"mailto:=
aribertn@gmail.com" target=3D"_blank">aribertn@gmail.com</a>" <<a h=
ref=3D"mailto:aribertn@gmail.com"; target=3D"_blank">aribertn@gmail.com</a>&=
gt;, "<a href=3D"mailto:triumphs@autox.team.net"; target=3D"_blank">tri=
umphs@autox.team.net</a>" <<a href=3D"mailto:triumphs@autox.team.ne=
t" target=3D"_blank">triumphs@autox.team.net</a>><br>Cc:=C2=A0<br>Bcc:=
=C2=A0<br>Date:=C2=A0Mon, 20 Mar 2023 13:30:54 +0000 (UTC)<br>Subject:=C2=
=A0Re: [TR] Calling anyone with transmission rebuilding experience - 2nd at=
tempt, part2<br>
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div> <font size=3D"3">That looks like the heat treated, hardened=C2=A0 sur=
face is starting to break up.=C2=A0 That is what happened to my layshaft.=
=C2=A0 Another reason to abandon that mainshaft.=C2=A0 If you have an alter=
nate bearing combination that doesn't relay on that surface for the bea=
ring rollers then the hardened surface is no longer critical.=C2=A0 But thi=
s is above my pay grade.<br>
</font></div>
<div><font size=3D"3"><br>
</font></div>
<div><font size=3D"3">BTW, I misinterpreted one of your previous photos.=C2=
=A0 The split washers transfer the lateral forces from the synchro hub to t=
he mainshaft but the end result is the same, with a compromised groove surf=
ace like that the split collars will fail prematurely.=C2=A0=C2=A0 If you o=
pen the grove to clean up the shoulder will the split washers stay in place=
?=C2=A0 If they fall out you have serious problems.=C2=A0 Even if they stay=
in place will it increase backlash?=C2=A0 Can you get oversized split coll=
ars?=C2=A0 Make shims?=C2=A0 All this is above my pay grade.<br>
</font></div>
<div> <br>
</div>
<div style=3D"clear:both">
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div style=3D"color:black;font:12pt Arial,Helvetica,sans-serif">
<div><font size=3D"4">Dave <br>
</font></div>
<div><span style=3D"font-size:10pt;font-family:sans-serif;color:black"><br>
</span></div>
<br>
</div>
</div>
</div>
<div> <br>
</div>
<div> <br>
</div>
<div style=3D"font-family:arial,helvetica;font-size:10pt;color:black"><font=
size=3D"2"><div id=3D"m_6593041711186351867yiv7397812571"><div dir=3D"ltr"=
><div><div dir=3D"ltr"><br></div><div dir=3D"ltr">
<div><br>
</div>
<div><br>
</div>
</div>
</div>
</div>
</div></font></div></div><br>
</blockquote></div></div>
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** triumphs@autox.team.net **
Archive: http://www.team.net/pipermail/triumphs http://www.team.net/archive
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