Source for 20mm & 25mm diameter elastomers?



R

Robert Perkins

Guest
I have a 20" suspension fork on my Hornet recumbent
(www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
defunct. I am looking for replacement MCU urethane or other elastomers.

I don't want to replace the fork because it has a special fitting to
allow the remote steering rod to attach to the fork. Plus, the headset
is 1 1/4" threaded- try finding one of those.

I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
of both. I plan to cut them to the right length, since the elastomers
are themselves 10mm thick, then separated from the next elastomer by a
plastic piece.

So, does anyone know where I can locate such beasts?

Thanks, Rob
 
Rob,

You could try [email protected] to ask for it. I don't know any
other source.

/Helge


"Robert Perkins" <[email protected]> wrote in message
news:[email protected]...
>I have a 20" suspension fork on my Hornet recumbent
>(www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
>defunct. I am looking for replacement MCU urethane or other elastomers.
>
> I don't want to replace the fork because it has a special fitting to allow
> the remote steering rod to attach to the fork. Plus, the headset is 1
> 1/4" threaded- try finding one of those.
>
> I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
> of both. I plan to cut them to the right length, since the elastomers are
> themselves 10mm thick, then separated from the next elastomer by a plastic
> piece.
>
> So, does anyone know where I can locate such beasts?
>
> Thanks, Rob
 
Robert Perkins wrote:
> I have a 20" suspension fork on my Hornet recumbent
> (www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
> defunct. I am looking for replacement MCU urethane or other elastomers.
>
> I don't want to replace the fork because it has a special fitting to
> allow the remote steering rod to attach to the fork. Plus, the headset
> is 1 1/4" threaded- try finding one of those.
>
> I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
> of both. I plan to cut them to the right length, since the elastomers
> are themselves 10mm thick, then separated from the next elastomer by a
> plastic piece.
>
> So, does anyone know where I can locate such beasts?
>
> Thanks, Rob


http://www.mcmaster.com/

go to the section with o-rings, and look for cord stock. you can buy 3'
of 1" [25mm] round buna-n for $3.79. 3/4" is 19mm. should last you a
while.
 
On Sun, 03 Feb 2008 11:38:20 -0500, Robert Perkins
<[email protected]> may have said:

>I have a 20" suspension fork on my Hornet recumbent
>(www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
>defunct. I am looking for replacement MCU urethane or other elastomers.
>
>I don't want to replace the fork because it has a special fitting to
>allow the remote steering rod to attach to the fork. Plus, the headset
>is 1 1/4" threaded- try finding one of those.
>
>I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
>of both. I plan to cut them to the right length, since the elastomers
>are themselves 10mm thick, then separated from the next elastomer by a
>plastic piece.
>
>So, does anyone know where I can locate such beasts?


You might want to investigate the possibility of using 20mm and 25mm
circular punches to cut rings from sheet stock of an appropriate
material. Of course, this presumes that the material can be had from
some source, which is itself a problem. I've had limited success
finding such sheet foams in the past when they were needed for the
construction of padded cases for equipment, but a little casting about
may produce a source. Part of the generalized problem in this regard
is that with the death of the paradigm of local production of goods,
the demand for small quantities of such materials is effectively
absent in many areas, and as a result there is no supply available
from any obvious source.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
 
In article <[email protected]>,
Werehatrack <[email protected]> wrote:

> On Sun, 03 Feb 2008 11:38:20 -0500, Robert Perkins
> <[email protected]> may have said:
>
> >I have a 20" suspension fork on my Hornet recumbent
> >(www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
> >defunct. I am looking for replacement MCU urethane or other elastomers.
> >
> >I don't want to replace the fork because it has a special fitting to
> >allow the remote steering rod to attach to the fork. Plus, the headset
> >is 1 1/4" threaded- try finding one of those.
> >
> >I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
> >of both. I plan to cut them to the right length, since the elastomers
> >are themselves 10mm thick, then separated from the next elastomer by a
> >plastic piece.
> >
> >So, does anyone know where I can locate such beasts?

>
> You might want to investigate the possibility of using 20mm and 25mm
> circular punches to cut rings from sheet stock of an appropriate
> material. Of course, this presumes that the material can be had from
> some source, which is itself a problem. I've had limited success
> finding such sheet foams in the past when they were needed for the
> construction of padded cases for equipment, but a little casting about
> may produce a source. Part of the generalized problem in this regard
> is that with the death of the paradigm of local production of goods,
> the demand for small quantities of such materials is effectively
> absent in many areas, and as a result there is no supply available
> from any obvious source.


Werehatrack, was there ever an era when MCU urethane would have been
widely produced by local producers? I'm sure you could have found it in
certain cities (either very large or where industry called for it), but
it seems to me that the centralizing and offshoring of a lot of goods
production has contributed to the diversity of materials easily
available to hobbyists.

I'm sorta trying to suggest that the era of small local manufacture
probably wasn't widely better at distributing goods, though places like
LA (aerospace!) were probably a bit more fun :).

-RjC, who hears the Boeing surplus sales in Seattle continue to be
pretty awesome,

--
Ryan Cousineau [email protected] http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."
 
On Sun, 03 Feb 2008 18:23:46 GMT, Ryan Cousineau <[email protected]>
may have said:

>In article <[email protected]>,
> Werehatrack <[email protected]> wrote:
>> ... Part of the generalized problem in this regard
>> is that with the death of the paradigm of local production of goods,
>> the demand for small quantities of such materials is effectively
>> absent in many areas, and as a result there is no supply available
>> from any obvious source.

>
>..Was there ever an era when MCU urethane would have been
>widely produced by local producers? I'm sure you could have found it in
>certain cities (either very large or where industry called for it), but
>it seems to me that the centralizing and offshoring of a lot of goods
>production has contributed to the diversity of materials easily
>available to hobbyists.


Local production largely died before MCU existed; prior to that,
however, many sources of the raw materials needed for a variety of
technologies were both common and readily available in most cities.

>I'm sorta trying to suggest that the era of small local manufacture
>probably wasn't widely better at distributing goods, though places like
>LA (aerospace!) were probably a bit more fun :).


In many instances, that which was not locally stocked could be had
with ease from readily identifiable and well-known mail-order sources,
but even those have gone away with the concentration of production of
most goods in large factories and/or overseas. I recall the tail end
of the death of local production of non-food items, and I also
remember some of those materials catalogs.

>-RjC, who hears the Boeing surplus sales in Seattle continue to be
>pretty awesome,


Some of that ends up on eBay from time to time. Sometimes, the
sellers have no idea what the stuff really is.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
 
In article <[email protected]>,
Werehatrack <[email protected]> wrote:

> On Sun, 03 Feb 2008 18:23:46 GMT, Ryan Cousineau <[email protected]>
> may have said:
>
> >In article <[email protected]>,
> > Werehatrack <[email protected]> wrote:
> >> ... Part of the generalized problem in this regard
> >> is that with the death of the paradigm of local production of goods,
> >> the demand for small quantities of such materials is effectively
> >> absent in many areas, and as a result there is no supply available
> >> from any obvious source.

> >
> >..Was there ever an era when MCU urethane would have been
> >widely produced by local producers? I'm sure you could have found it in
> >certain cities (either very large or where industry called for it), but
> >it seems to me that the centralizing and offshoring of a lot of goods
> >production has contributed to the diversity of materials easily
> >available to hobbyists.

>
> Local production largely died before MCU existed; prior to that,
> however, many sources of the raw materials needed for a variety of
> technologies were both common and readily available in most cities.
>
> >I'm sorta trying to suggest that the era of small local manufacture
> >probably wasn't widely better at distributing goods, though places like
> >LA (aerospace!) were probably a bit more fun :).

>
> In many instances, that which was not locally stocked could be had
> with ease from readily identifiable and well-known mail-order sources,
> but even those have gone away with the concentration of production of
> most goods in large factories and/or overseas. I recall the tail end
> of the death of local production of non-food items, and I also
> remember some of those materials catalogs.


On the other hand, the Internet is pretty cool too:

http://www.acrotechinc.com/sheets.htm
http://www.acrotechinc.com/pdf_library.htm

Alas, their eBay store for overstock and seconds no longer appears to be
active.

I do not believe that in previous decades it would have been quite as
simple for me to find a supplier for a random material from my bathtub.
:)

--
Ryan Cousineau [email protected] http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."
 
Robert Perkins wrote:
> I have a 20" suspension fork on my Hornet recumbent
> (www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
> defunct. I am looking for replacement MCU urethane or other elastomers.
>
> I don't want to replace the fork because it has a special fitting to
> allow the remote steering rod to attach to the fork. Plus, the headset
> is 1 1/4" threaded- try finding one of those.
>
> I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
> of both. I plan to cut them to the right length, since the elastomers
> are themselves 10mm thick, then separated from the next elastomer by a
> plastic piece.
>
> So, does anyone know where I can locate such beasts?
>
> Thanks, Rob


Try McMaster-Carr <http://www.mcmaster.com/>. They have a variety of
elastomers in stock sizes. I wouldn't obsess too much about finding the
exact material, it wasn't all that special. You might be better off
finding a compression spring of the right characteristics.
 
On Mon, 04 Feb 2008 09:08:17 -0500, Peter Cole wrote:

> Robert Perkins wrote:
>> I have a 20" suspension fork on my Hornet recumbent
>> (www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
>> defunct. I am looking for replacement MCU urethane or other elastomers.
>>
>> I don't want to replace the fork because it has a special fitting to
>> allow the remote steering rod to attach to the fork. Plus, the headset
>> is 1 1/4" threaded- try finding one of those.
>>
>> I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
>> of both. I plan to cut them to the right length, since the elastomers
>> are themselves 10mm thick, then separated from the next elastomer by a
>> plastic piece.
>>
>> So, does anyone know where I can locate such beasts?
>>
>> Thanks, Rob

>
> Try McMaster-Carr <http://www.mcmaster.com/>. They have a variety of
> elastomers in stock sizes. I wouldn't obsess too much about finding the
> exact material, it wasn't all that special. You might be better off
> finding a compression spring of the right characteristics.


Elastomers have internal damping - that's one of the reasons they are
used(so do spings, but it is very very much smaller).
 
"Ryan Cousineau" <[email protected]> wrote in message
news:rcousine-342AAC.10234203022008@[74.223.185.199.nw.nuvox.net]...
| In article <[email protected]>,
| Werehatrack <[email protected]> wrote:
|
| > On Sun, 03 Feb 2008 11:38:20 -0500, Robert Perkins
| > <[email protected]> may have said:
| >
| > >I have a 20" suspension fork on my Hornet recumbent
| > >(www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
| > >defunct. I am looking for replacement MCU urethane or other
elastomers.
| > >
| > >I don't want to replace the fork because it has a special fitting to
| > >allow the remote steering rod to attach to the fork. Plus, the
headset
| > >is 1 1/4" threaded- try finding one of those.
| > >
| > >I need 20mm diameter, and 25mm diameter elastomers. I need 200mm
length
| > >of both. I plan to cut them to the right length, since the elastomers
| > >are themselves 10mm thick, then separated from the next elastomer by a
| > >plastic piece.
| > >
| > >So, does anyone know where I can locate such beasts?
| >
| > You might want to investigate the possibility of using 20mm and 25mm
| > circular punches to cut rings from sheet stock of an appropriate
| > material. Of course, this presumes that the material can be had from
| > some source, which is itself a problem. I've had limited success
| > finding such sheet foams in the past when they were needed for the
| > construction of padded cases for equipment, but a little casting about
| > may produce a source. Part of the generalized problem in this regard
| > is that with the death of the paradigm of local production of goods,
| > the demand for small quantities of such materials is effectively
| > absent in many areas, and as a result there is no supply available
| > from any obvious source.
|
| Werehatrack, was there ever an era when MCU urethane would have been
| widely produced by local producers? I'm sure you could have found it in
| certain cities (either very large or where industry called for it), but
| it seems to me that the centralizing and offshoring of a lot of goods
| production has contributed to the diversity of materials easily
| available to hobbyists.
|
| I'm sorta trying to suggest that the era of small local manufacture
| probably wasn't widely better at distributing goods, though places like
| LA (aerospace!) were probably a bit more fun :).
|
| -RjC, who hears the Boeing surplus sales in Seattle continue to be
| pretty awesome,
|
| --

I've read that skateboard bushings (see link below) can be used to replace
the elastomers on Girvin Flexstems. I don't know the size of the elastomers
at the following link, but check them out ...they may work for your fork

http://www.outlookskates.com/Bushings2.htm
 
On Mon, 04 Feb 2008 14:12:16 GMT, _
<[email protected]> may have said:

>On Mon, 04 Feb 2008 09:08:17 -0500, Peter Cole wrote:
>
>> Robert Perkins wrote:
>>> I have a 20" suspension fork on my Hornet recumbent
>>> (www.radius-liegerader.de). The fork manufacturer, Kangaroo, is now
>>> defunct. I am looking for replacement MCU urethane or other elastomers.
>>>
>>> I don't want to replace the fork because it has a special fitting to
>>> allow the remote steering rod to attach to the fork. Plus, the headset
>>> is 1 1/4" threaded- try finding one of those.
>>>
>>> I need 20mm diameter, and 25mm diameter elastomers. I need 200mm length
>>> of both. I plan to cut them to the right length, since the elastomers
>>> are themselves 10mm thick, then separated from the next elastomer by a
>>> plastic piece.
>>>
>>> So, does anyone know where I can locate such beasts?
>>>
>>> Thanks, Rob

>>
>> Try McMaster-Carr <http://www.mcmaster.com/>. They have a variety of
>> elastomers in stock sizes. I wouldn't obsess too much about finding the
>> exact material, it wasn't all that special. You might be better off
>> finding a compression spring of the right characteristics.

>
>Elastomers have internal damping - that's one of the reasons they are
>used(so do spings, but it is very very much smaller).


It's much easier and cheaper to make an elastomer damped-spring unit
than a hydraulically-damped coil or compressed gas spring, that's for
sure. And there have been some abysmal versions of the latter in the
suspension fork area. (A certain "Zokes Nitro", which was NOT made by
Marzocchi, comes to mind as a brilliant example of excrescence in
execution of a poor design.)

One thing that must be taken into consideration when choosing
materials to use in a fork, however, is compatibility with the
essential grease that they will be exposed to. Some foams will
degrade quickly in the presence of certain greases. Skateboard
doughnuts should be OK in that regard, but their compression rate may
be much too stiff to be useful.

I recall that some of the fork makers used to provide optional MCU
replacement packages for heavier or lighter riders; perhaps casting
around for some of those might be a fruitful way to find what the OP
needs.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.