I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.

--
Creativity is allowing yourself to make mistakes.
Art is knowing which ones to keep.
-- Scott Adams, 'The Dilbert Principle'

"unk" wrote in message
...
I'm repairing an crank handle for a nice old tripod. The handle is
made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the
u-shaped
channel of the plastic. I expect there is a bit of draft so the
epoxy
I'm planing on using to embed the steel bit has to stick good to
that
plastic.

Recommendations?

http://antiqueradios.com/forums/viewtopic.php?t=103903

I reinforce handles that have broken and may (will) again with a metal
sleeve, a hobby-store brass tube in the center if it's decorative or
outside ferrules pressed and swaged onto the ends if it isn't.

-jsw

On Mon, 28 Dec 2015 04:55:53 -0800, Larry Jaques wrote:

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.


This one's broken right where the end of the u-channel meets the spinner-
knob mount. It's across the narrowest part of the 45 degree join.
Here's a pic of the handle:

https://www.manfrottospares.com/en/i...route=product/
product&product_id=9294

The knob mounts into a 15/64" hole that leaves about 1/2" vacant on the
back side. I cut a bit of drill that size and silver soldered it into a
bit of 3/16" by file-to-fit that is bent at 45 - disappears right into
the u-channel and as long as it stays there it will be stronger than the
original.

I was wondering if prepping it with an agressive solvent like carb
cleaner would help; also though of keying the sides of the channel so the
epoxy block would not just be reliant on surface adhesion.

On Mon, 28 Dec 2015 14:07:50 -0000 (UTC), unk wrote:

On Mon, 28 Dec 2015 04:55:53 -0800, Larry Jaques wrote:

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.


This one's broken right where the end of the u-channel meets the spinner-
knob mount. It's across the narrowest part of the 45 degree join.
Here's a pic of the handle:

https://www.manfrottospares.com/en/i...route=product/
product&product_id=9294

The knob mounts into a 15/64" hole that leaves about 1/2" vacant on the
back side. I cut a bit of drill that size and silver soldered it into a
bit of 3/16" by file-to-fit that is bent at 45 - disappears right into
the u-channel and as long as it stays there it will be stronger than the
original.

I was wondering if prepping it with an agressive solvent like carb
cleaner would help; also though of keying the sides of the channel so the
epoxy block would not just be reliant on surface adhesion.

Whether the epoxy sticks will depend on the type of plastic and how
much plasticizer it has in it. In any case, that's a marginal joint.

If that bent piece is long enough, you could wrap the joined area in
fiberglass, soaking it with epoxy as you wrap, until it's as ugly as
you can tolerate it. g Overwrap that with Saran wrap and then sand
it off when you're done. That will make it a little neater.

--
Ed Huntress

Ed Huntress fired this volley in
:

Whether the epoxy sticks will depend on the type of plastic and how
much plasticizer it has in it. In any case, that's a marginal joint.

Why not use the old handle as a pattern, and make another from (say) solid
aluminum?

L

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?
There is available now at many hardware stores a two part adhesive
made for plastics. I bought some to make a temporary repair to the
plastic radiator in a Toyata Camry. The top was cracked so I used the
two part stuff with cloth reinforcement to seal the two inch long
crack until the new radiator arrived. The repair held for over a week.
I don't know how long it would have held because the new radiator
arrived and I installed it. I don't know how well it would stick to
steel though.
Eric

On Mon, 28 Dec 2015 14:07:50 -0000 (UTC), unk wrote:

On Mon, 28 Dec 2015 04:55:53 -0800, Larry Jaques wrote:

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.


This one's broken right where the end of the u-channel meets the spinner-
knob mount. It's across the narrowest part of the 45 degree join.
Here's a pic of the handle:

https://www.manfrottospares.com/en/i...route=product/
product&product_id=9294

The knob mounts into a 15/64" hole that leaves about 1/2" vacant on the
back side. I cut a bit of drill that size and silver soldered it into a
bit of 3/16" by file-to-fit that is bent at 45 - disappears right into
the u-channel and as long as it stays there it will be stronger than the
original.

I was wondering if prepping it with an agressive solvent like carb
cleaner would help; also though of keying the sides of the channel so the
epoxy block would not just be reliant on surface adhesion.
Mechanically rough up the surface of the plastic to give it some
"tooth", then glue with a good repair epoxy.(I have no brand
preference, but I have some "west system" stuff left over from
aircraft work that I would likely use in a case like that - if it were
me.

Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
Ed Huntress fired this volley in
:

Whether the epoxy sticks will depend on the type of plastic and how
much plasticizer it has in it. In any case, that's a marginal joint.

Why not use the old handle as a pattern, and make another from (say) solid
aluminum?

Or just buy a new one? Manfrotto has lots of spare parts for sale. Any
hacked up plastic crank is bound to look horrible after repair anyways.

On Mon, 28 Dec 2015 12:15:11 -0500, wrote:

On Mon, 28 Dec 2015 14:07:50 -0000 (UTC), unk wrote:

On Mon, 28 Dec 2015 04:55:53 -0800, Larry Jaques wrote:

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.


This one's broken right where the end of the u-channel meets the spinner-
knob mount. It's across the narrowest part of the 45 degree join.
Here's a pic of the handle:

https://www.manfrottospares.com/en/i...route=product/
product&product_id=9294

The knob mounts into a 15/64" hole that leaves about 1/2" vacant on the
back side. I cut a bit of drill that size and silver soldered it into a
bit of 3/16" by file-to-fit that is bent at 45 - disappears right into
the u-channel and as long as it stays there it will be stronger than the
original.

I was wondering if prepping it with an agressive solvent like carb
cleaner would help; also though of keying the sides of the channel so the
epoxy block would not just be reliant on surface adhesion.
Mechanically rough up the surface of the plastic to give it some
"tooth", then glue with a good repair epoxy.(I have no brand
preference, but I have some "west system" stuff left over from
aircraft work that I would likely use in a case like that - if it were
me.

A1 Metalset is an example

On 12/28/2015 11:15 AM, wrote:
On Mon, 28 Dec 2015 14:07:50 -0000 (UTC), unk wrote:

On Mon, 28 Dec 2015 04:55:53 -0800, Larry Jaques wrote:

On Mon, 28 Dec 2015 12:23:39 -0000 (UTC), unk wrote:

I'm repairing an crank handle for a nice old tripod. The handle is made
of some sort of black plastic, and the bit made to repair (reinforce
across the break) it is steel. The steel bit sits inside the u-shaped
channel of the plastic. I expect there is a bit of draft so the epoxy
I'm planing on using to embed the steel bit has to stick good to that
plastic.

Recommendations?

That's a high-energy repair, with rotational as well as axial loads.

I'd probably drill, tap, and screw the piece together with 4 small
screws, perhaps with some 3m 5200 adhesive (or ShoeGoo) to initially
stick it together.


This one's broken right where the end of the u-channel meets the spinner-
knob mount. It's across the narrowest part of the 45 degree join.
Here's a pic of the handle:

https://www.manfrottospares.com/en/i...route=product/
product&product_id=9294

The knob mounts into a 15/64" hole that leaves about 1/2" vacant on the
back side. I cut a bit of drill that size and silver soldered it into a
bit of 3/16" by file-to-fit that is bent at 45 - disappears right into
the u-channel and as long as it stays there it will be stronger than the
original.

I was wondering if prepping it with an agressive solvent like carb
cleaner would help; also though of keying the sides of the channel so the
epoxy block would not just be reliant on surface adhesion.
Mechanically rough up the surface of the plastic to give it some
"tooth", then glue with a good repair epoxy.(I have no brand
preference, but I have some "west system" stuff left over from
aircraft work that I would likely use in a case like that - if it were
me.

My go to epoxy is Huntsman 10, previously Araldite by Ciba Geigy
http://tinyurl.com/nlnldt3
That's the small tube, I generally buy it in the 9 oz size, but Amazon
is out, you can probably find it elsewhere. I has a long shelf life even
after opened. I've used it after 10 years. It's grey when mixed.
http://www.amazon.com/Huntsman-Fastw...ct_top?ie=UTF8
I did a repair similar to yours on a on my radial arm saw crank handle
more than 15 years ago, it's still holding strong. That handle is all
aluminum, but I used Fastweld 10 for years on plastic parts in the
consumer electronics repair business. Where ever possible we used 0.25"
or 0.35" steel rod to pin parts before epoxy.
Mikek