Grant,
On 1/3/2012 10:05 PM, Grant Saviers wrote:
> I checked my reference text, "Handbook of Fibre Rope Technology" and
> Dyneema has excessive creep vs Kevlar.
Thanks for the confirmation.
Looks like these Mastrant ropes might be useful for temporary tower
installations at 10% preload but would require constant adjustment in
permanent service. These ropes might also be interesting for use with
an AB-577 or AB-621 with their temporary nature or for guying 80/160
meter verticals with their relatively low static loads.
73,
... Joe, W4TV
On 1/3/2012 10:05 PM, Grant Saviers wrote:
> I checked my reference text, "Handbook of Fibre Rope Technology" and
> Dyneema has excessive creep vs Kevlar.
>
> Dyneema SK60 creeps 0.63% at 15% of breaking load in 100 days. At 30%
> load it creeps 9% in 100 days!
>
> Kevlar 49 creeps 0.041% and 0.05% respectively. A search for "creep" on
> the Phillystran web site yielded no hits.
>
> The Mastrant web site says they are using Dyneema SK75 which another
> reference shows 22% creep at 30% load in 20 days
> http://www.abcm.org.br/symposiumSeries/SSSM_Vol2/Contents/SSSM_05.pdf
>
> So the guying application seems wrong for Dyneema fibers. Spectra is an
> even worse choice. Polyester creep is about 5x worse than Kevlar
>
> OTOH, Phillystran is well proven and presumably contains the best Kevlar
> fiber for making permanent guy wires.
>
> Grant KZ1W
>
>
> On 1/3/2012 6:15 PM, Joe Subich, W4TV wrote:
>> On 1/3/2012 5:18 PM, K1TTT wrote:
>>> Check the original linked page, that place is only selling the 'P'
>>> type which is the polyester one(and only on special order at that).
>> Check again ... list all the products from that company on the R and L
>> site. You will find both the D and the F2-D ropes which are Dyneema
>> core (similar in performance/strength to Kevlar). The problem - as
>> explained to me - is that although Dyneema will not stretch under
>> dynamic load it will "creep" (slowly elongate) under static loads
>> like those encountered in guying applications.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>> On 1/3/2012 5:18 PM, K1TTT wrote:
>>> Check the original linked page, that place is only selling the 'P' type
>>> which is the polyester one(and only on special order at that). The 'D'
>>> versions are on the manufacturer's page, and while the specs are
>>> better they
>>> are still only hd polyethylene rope.
>>>
>>> David Robbins K1TTT
>>> e-mail: mailto:k1ttt@arrl.net
>>> web: http://wiki.k1ttt.net
>>> AR-Cluster node: 145.69MHz or telnet://k1ttt.net
>>>
>>> -----Original Message-----
>>> From: Wayne Kline [mailto:w3ea@hotmail.com]
>>> Sent: Tuesday, January 03, 2012 20:58
>>> To: K1TTT; towertalk@contesting.com
>>> Subject: Re: [TowerTalk] Mastrant Rope ? guy wire ?
>>>
>>>
>>> My Frist Thought Dave Till I dug into it http://www.mastrant.com/en
>>> Wayne
>>> W3EA> Date: Tue, 3 Jan 2012 11:57:06 -0600
>>>> From: k1ttt@verizon.net
>>>> To: towertalk@contesting.com
>>>> Subject: Re: [TowerTalk] Mastrant Rope ? guy wire ?
>>>>
>>>>
>>>> thats just a polyester rope not a tower guy material unless you need it
>>> for a temporary field day type tower.
>>>>
>>>>
>>>> Jan 3, 2012 12:43:42 PM, w3ea@hotmail.com wrote:
>>>>
>>>>
>>>>
>>>> Hi TT'ers HNY Planning my spring 10 meter tower antenna 5/5 35'-72'
>>>> rebuild. The 3/16 guy wire broken up with 502 insulators levels 32'
>>>> 64' It's in good shape but has rust wash near there attachment points
>>>> ! It's been up 22 years in this acid NE rain a new paint job new feed
>>>> lines rebuild the rotors .. why not new guy support. I Was thinking of
>>>> doing Phillystran, at least on the top layer. While researching it I
>>>> stumbled across a product Sold in the USA by RL Electronics in OH.
>>>> Mastrant guy rope !
>>>> http://store.rlham.com/shop/catalog/advanced_search_result.php?keyword
>>>> s=mastrant+and+mp&x=5&y=5Any TT'ers have any experience with this
>>>> stuff ? Have experience with all the old style and new type Philly
>>>> stuff and the Fiber-rod. nonconductive guying material . But this is a
>>>> new one for me. Thanks 73's Wayne W3EA
>>>> _______________________________________________
>>>>
>>>>
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