Motorbike Forums


Reply
Thread Tools Display Modes

Paging the stripped thread recovery experts - Plastic so helicoil not an option.

 
 
Pete Fisher
Guest
Posts: n/a
 
      11-19-2010, 04:49 PM
So the new M4x70 screws I sourced for the CEV rear light unit are
exactly right, except that now I remember why one was missing - the
thread in the mounting has stripped. This is the thread in a plastic
moulded 'tube' that forms part of the light reflector base. I have a
spare from the Strada I am breaking, but surprise, surprise that lens
was also held on by electrical tape and both the threads are stripped.

No chance of a helicoil or similar and as the lens obviously needs to
come off to change a bulb occasionally a simple adhesive solution isn't
practical.

All I can think of doing is filling the tube completely with bumper
repair (the two part black stuff which is v. good for repairing well
bumpers and other plastic parts) and then screwing in a screw liberally
coated with copper grease. Wait for the goo to have nearly set and
carefully take out the screw to leave a new 'plastic' thread to harden.

Is this likely to work, or am I going to end up with a permanently
bonded screw and tube?
--
+-------------------------------------------------------------------+
| Pete Fisher at Home: (E-Mail Removed) |
| Aprilia Shiver Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+
 
Reply With Quote
 
 
 
 
Pete Fisher
Guest
Posts: n/a
 
      11-19-2010, 05:11 PM
In message <(E-Mail Removed)>, Mark Olson
<(E-Mail Removed)> writes
>Pete Fisher wrote:
>> So the new M4x70 screws I sourced for the CEV rear light unit are
>>exactly right, except that now I remember why one was missing - the
>>thread in the mounting has stripped. This is the thread in a plastic
>>moulded 'tube' that forms part of the light reflector base. I have a
>>spare from the Strada I am breaking, but surprise, surprise that lens
>>was also held on by electrical tape and both the threads are stripped.
>> No chance of a helicoil or similar and as the lens obviously needs
>>to come off to change a bulb occasionally a simple adhesive solution
>>isn't practical.
>> All I can think of doing is filling the tube completely with bumper
>>repair (the two part black stuff which is v. good for repairing well
>>bumpers and other plastic parts) and then screwing in a screw
>>liberally coated with copper grease. Wait for the goo to have nearly
>>set and carefully take out the screw to leave a new 'plastic' thread
>>to harden.
>> Is this likely to work, or am I going to end up with a permanently
>>bonded screw and tube?

>
>Just fill the hole with JB Weld and drill and tap it afterward.


Probably the more elegant solution. Which reminds me that I didn't get
to Lidl for that cheap set of taps and dies. I'm not sure if I have an
M4 tap, though I think I have an ancient pikey compendium somewhere. Got
a set of three (1st cut, 2nd cut and plug) good quality ones for M8, but
not much else.

I already have tubes of Bumper Repair and copper grease though.
Spoiling the ship for a 'happorth of tar perhaps.


--

+-----------------------------------------------------------------+
| Pete Fisher at Home: (E-Mail Removed) |
| Visit my *NEW* Home Page : http://www.flarefox.com/Joomla |
| "Do not adjust your mind - there is a fault in the reality" |
+-----------------------------------------------------------------+
 
Reply With Quote
 
The Older Gentleman
Guest
Posts: n/a
 
      11-19-2010, 05:46 PM
Mark Olson <(E-Mail Removed)> wrote:

> JB Weld is the best product I have ever seen for fixing what it otherwise
> unfixable. It really is the next thing to miraculous.


Agree 100%.


--
BMW K1100LT Ducati 750SS Honda CB400Fx2 Triumph Street Triple
Kawasaki GT550 Suzuki TS250ERx2 GN250 Back to nine bikes!
Try Googling before asking a damn silly question.
chateau dot murray at idnet dot com
 
Reply With Quote
 
Pete Fisher
Guest
Posts: n/a
 
      11-19-2010, 05:59 PM
In communiqué <1js7w07.b4k00rc0zfl2N%(E-Mail Removed) .uk>,
The Older Gentleman <(E-Mail Removed)> cast forth these
pearls of wisdom
>Mark Olson <(E-Mail Removed)> wrote:
>
>> JB Weld is the best product I have ever seen for fixing what it otherwise
>> unfixable. It really is the next thing to miraculous.

>
>Agree 100%.
>
>


<googles>

--
+-------------------------------------------------------------------+
| Pete Fisher at Home: (E-Mail Removed) |
| Aprilia Shiver Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+
 
Reply With Quote
 
Andy Bonwick
Guest
Posts: n/a
 
      11-19-2010, 06:01 PM
On Fri, 19 Nov 2010 18:11:25 +0000, Pete Fisher
<(E-Mail Removed)> wrote:

>In message <(E-Mail Removed)>, Mark Olson
><(E-Mail Removed)> writes
>>Pete Fisher wrote:
>>> So the new M4x70 screws I sourced for the CEV rear light unit are
>>>exactly right, except that now I remember why one was missing - the
>>>thread in the mounting has stripped. This is the thread in a plastic
>>>moulded 'tube' that forms part of the light reflector base. I have a
>>>spare from the Strada I am breaking, but surprise, surprise that lens
>>>was also held on by electrical tape and both the threads are stripped.
>>> No chance of a helicoil or similar and as the lens obviously needs
>>>to come off to change a bulb occasionally a simple adhesive solution
>>>isn't practical.
>>> All I can think of doing is filling the tube completely with bumper
>>>repair (the two part black stuff which is v. good for repairing well
>>>bumpers and other plastic parts) and then screwing in a screw
>>>liberally coated with copper grease. Wait for the goo to have nearly
>>>set and carefully take out the screw to leave a new 'plastic' thread
>>>to harden.
>>> Is this likely to work, or am I going to end up with a permanently
>>>bonded screw and tube?

>>
>>Just fill the hole with JB Weld and drill and tap it afterward.

>
>Probably the more elegant solution. Which reminds me that I didn't get
>to Lidl for that cheap set of taps and dies. I'm not sure if I have an
>M4 tap, though I think I have an ancient pikey compendium somewhere. Got
>a set of three (1st cut, 2nd cut and plug) good quality ones for M8, but
>not much else.
>

Fill it and re-tap it properly. If I haven't got an M4 tap I can drop
in the post to you I'll abuse my power and order a set.

Why can't you use a helicoil? The only reason I can think of is if
it's too badly ****ed and if that's the case then you'll be better
trying to plastic weld it with a bit of similar plastic and a
soldering iron before tapping it rather than using a chemical filler.

 
Reply With Quote
 
Pete Fisher
Guest
Posts: n/a
 
      11-19-2010, 06:10 PM
In communiqué <(E-Mail Removed)>, Andy Bonwick
<(E-Mail Removed)> cast forth these pearls of wisdom
>On Fri, 19 Nov 2010 18:11:25 +0000, Pete Fisher
><(E-Mail Removed)> wrote:
>
>>In message <(E-Mail Removed)>, Mark Olson
>><(E-Mail Removed)> writes
>>>Pete Fisher wrote:
>>>> So the new M4x70 screws I sourced for the CEV rear light unit are
>>>>exactly right, except that now I remember why one was missing - the
>>>>thread in the mounting has stripped. This is the thread in a plastic
>>>>moulded 'tube' that forms part of the light reflector base. I have a
>>>>spare from the Strada I am breaking, but surprise, surprise that lens
>>>>was also held on by electrical tape and both the threads are stripped.
>>>> No chance of a helicoil or similar and as the lens obviously needs
>>>>to come off to change a bulb occasionally a simple adhesive solution
>>>>isn't practical.
>>>> All I can think of doing is filling the tube completely with bumper
>>>>repair (the two part black stuff which is v. good for repairing well
>>>>bumpers and other plastic parts) and then screwing in a screw
>>>>liberally coated with copper grease. Wait for the goo to have nearly
>>>>set and carefully take out the screw to leave a new 'plastic' thread
>>>>to harden.
>>>> Is this likely to work, or am I going to end up with a permanently
>>>>bonded screw and tube?
>>>
>>>Just fill the hole with JB Weld and drill and tap it afterward.

>>
>>Probably the more elegant solution. Which reminds me that I didn't get
>>to Lidl for that cheap set of taps and dies. I'm not sure if I have an
>>M4 tap, though I think I have an ancient pikey compendium somewhere. Got
>>a set of three (1st cut, 2nd cut and plug) good quality ones for M8, but
>>not much else.
>>

>Fill it and re-tap it properly. If I haven't got an M4 tap I can drop
>in the post to you I'll abuse my power and order a set.
>


I ought to be properly equipped as I now have more time to fettle SO
bikes but the offer is appreciated. Off to Lidl tomorrow and will also
get a drill stand if there are any left.

>Why can't you use a helicoil? The only reason I can think of is if
>it's too badly ****ed and if that's the case then you'll be better
>trying to plastic weld it with a bit of similar plastic and a
>soldering iron before tapping it rather than using a chemical filler.
>


The plastic tubes that stick out from the rest of the back of the light
unit are very thin walled (one is also coming loose from the rest of the
assembly and needs strengthening with JBweld or similar anyway). I can't
see that there is enough meat for a helicoil. Otherwise I might have got
brutal and just drilled and tapped them out to M5 and worried how to
enlarge the hole in the lens without cracking it later. As someone
suggested when I couldn't find long screws, I could use lengths of all
thread right through to the back of the unit with nuts on that end and
dome nuts to hold the lens on. Or just even longer screws and nuts. TBH
that's probably the easiest fix of all if I could find M4 x 80 screws.



--
+-------------------------------------------------------------------+
| Pete Fisher at Home: (E-Mail Removed) |
| Aprilia Shiver Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+
 
Reply With Quote
 
Wicked Uncle Nigel
Guest
Posts: n/a
 
      11-19-2010, 06:45 PM
Using the patented Mavis Beacon "Hunt&Peck" Technique, Pete Fisher
<(E-Mail Removed)> typed
>
>Probably the more elegant solution. Which reminds me that I didn't get
>to Lidl for that cheap set of taps and dies. I'm not sure if I have an
>M4 tap


I have. Chuck me an address and I'll pop it in the post. You can send it
back when you're done.

--
Wicked Uncle Nigel - "He's hopeless, but he's honest"

Contains moderate bullshit and simulated opinions.
 
Reply With Quote
 
Pete Fisher
Guest
Posts: n/a
 
      11-19-2010, 06:53 PM
In communiqué <(E-Mail Removed)>, Wicked Uncle
Nigel <(E-Mail Removed)> cast forth these pearls of wisdom
>Using the patented Mavis Beacon "Hunt&Peck" Technique, Pete Fisher
><(E-Mail Removed)> typed
>>
>>Probably the more elegant solution. Which reminds me that I didn't get
>>to Lidl for that cheap set of taps and dies. I'm not sure if I have an
>>M4 tap

>
>I have. Chuck me an address and I'll pop it in the post. You can send
>it back when you're done.
>


Very kind, but see reply to Andy. If I can't find my ancient pikey tap
and die set I will get one from Lidl tomorrow. I'm bound to need them
more in the future. Once the 2C/375 is complete (and it very nearly is)
I am turning my attention to the SO YZ250 and the spare Morini 350
engines. Bound to hit some dodgy threads on those. Mind you, I'm upping
the prioritisation of the not required Morini bits Togging out on Ebay.
Two plastic knobs with a bit of M5 thread sticking out for securing the
dual seat on a 350. Already up to £6.50 with 9 days to go. TOG is right,
it's many a mickle that macks a muckle.

--
+-------------------------------------------------------------------+
| Pete Fisher at Home: (E-Mail Removed) |
| Aprilia Shiver Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+
 
Reply With Quote
 
Wicked Uncle Nigel
Guest
Posts: n/a
 
      11-19-2010, 07:07 PM
Using the patented Mavis Beacon "Hunt&Peck" Technique, Pete Fisher
<(E-Mail Removed)> typed
>In communiqué <(E-Mail Removed)>, Wicked Uncle
>Nigel <(E-Mail Removed)> cast forth these pearls of wisdom
>>
>>I have. Chuck me an address and I'll pop it in the post. You can send
>>it back when you're done.
>>

>
>Very kind, but see reply to Andy.


Saw that later, fair enough. Let me know if you get stuck, and the
WUNderland machine shop is always at your disposal.

--
Wicked Uncle Nigel - "He's hopeless, but he's honest"

Contains moderate bullshit and simulated opinions.
 
Reply With Quote
 
GeoffC
Guest
Posts: n/a
 
      11-19-2010, 08:00 PM
Mark Olson wrote:
> Pete Fisher wrote:

<SNIP>

>> All I can think of doing is filling the tube completely with bumper
>> repair (the two part black stuff which is v. good for repairing well
>> bumpers and other plastic parts) and then screwing in a screw
>> liberally coated with copper grease. Wait for the goo to have nearly
>> set and carefully take out the screw to leave a new 'plastic' thread
>> to harden. Is this likely to work, or am I going to end up with a
>> permanently
>> bonded screw and tube?

>
> Just fill the hole with JB Weld and drill and tap it afterward.


I've used epoxy for building boats and it is indeed wonderful stuff. It sets
rockhard so that self-tappers will not work, you have to drill and tap.
It will stick to virtually anything except PVC and if you accidentally
manage to glue a screw tight you just have to heat the screw with a
soldering iron and it will melt the epoxy just enough to free the screw.

--

Geoff


 
Reply With Quote
 
 
 
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Paging the stripped thread recovery experts - Plastic so helicoil not an option. Pete Fisher UK Motorcycles 25 11-23-2010 09:48 PM


All times are GMT. The time now is 10:24 PM.

1 2 3 4 5 6 7 8 9