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What type of plastic line for this application?

What type of plastic line for this application?

What type of plastic line for this application?

(OP)
I'm trying to work out the best type of plastic line for an application requiring  good sustained load properties, minimal plastic or elastic deformation under operating conditions, good UV tolerance. If possible, it would be transparent, translucent, or at the very least white in color.

For operating conditions, it will be underwater, exposed to direct sunlight, and under a sustained load of around 60 kg. Elasticity and stretch must be minimal. Operating temperature range would be about -12° C to 45° C.

My needs sound a lot like a high-strength fishing line. But most of those lines don't really provide good data on elasticity, UV tolerance, effect of temperature on strength, etc.

A lot of high tension polymer fiber based ropes are out there, but they tend to be drastically overkill for my application - the load values and diameters are grossly larger than I need, and consequently quite expensive.

Any suggestions on what / where to look for the kind of material I need?

RE: What type of plastic line for this application?

Nylon monofilament yarn, also known as suture sewing thread or fishing line depending on diameter and grade of resin.

This is the only material that will be translucent, reasonably UV resistant and very strong.

Unfortunately as your question is quite subjective it is impossible to provide objective data.

Nylon tyre cord might be a good source of data as tyres operate at the temperature ranges you quote, although the properties will be reduced due to water absorption if the line is constantly submerged. Nylon is quite good to UV and can easily be improved with stabilisers.

Do you need to tie knots.

Could you use a thin multifilament yarn that is coaed to protect it from UV. You would loose transparency but you would open up the potential polyme choice to include aramid.  


 

Regards
Pat
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RE: What type of plastic line for this application?

(OP)
Clarity is not crucial. A white material would be acceptable, should transparent/translucent materials not be viable, particularly if it is small.

I need the line to stretch by no more than maybe 1% under full load. If possible, we'd be more like 0.1%.

Knots wouldn't necessarily be required. I guess some of this comes back to the mounting system.

Can you point me in the direction of some specs for some of these materials? I have a hard time finding things that are "more than fishing line" and "less than high tensile engineering rope" in terms of size/spec/pricing.

Because I can't figure out exactly what I'm seeking in terms of how it would be named on the market, it's hard to find suppliers, manufacturers, specifications, etc.

RE: What type of plastic line for this application?

Aramid fibre will be the best re tensile strength and elongation.

Trade names are Kevlar and Twaron.

You will need to sheath it to protect from UV light.

Generally propeties are:-

Very poor to UV.
Very poor in compression hence very poor knot strength.
Very low elongation at break.
Tensile strength stronger than steel size for size and seven times stronger than steel weight for weight.

Uses.

Bullet proof vests.
Hard armour.
Reinforcement of very high performance tyres.
Reinforcement of light weight high pressure hoses.
Guy wires for suspension bridges.
FRP as a substitute for glass where high modulus and impact are required such as top end sporting goods, high tech military and aerospace.
Optical fibre cable central strength members.

Typical idividual fibre properties:-
Denity                        1.45
Decomposition temperature     >500C
Tensile strength              1950 mN/tex
                              22.1 g/denier
                              2800 MPa
Initial Modulus               55 to 85 N/tex
                              80 to 125 GPa
Elongation at break           2.0 to 3.3%
Moisture regain               2.5 to 4.5%
Heat resistance (retained strength 48h 200C) 90%


Does this help

More information available from DuPont or Akzo Nobel.




 

Regards
Pat
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RE: What type of plastic line for this application?


Try searching for monofilament wire and aramid or kevlar fiber cable. We've used tendon wire from here:

http://www.applied-fiber.com/fiber-options.html

Trevor Clarke. (R & D) Scientific Instruments.Somerset. UK

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RE: What type of plastic line for this application?

Dynema is gel spun PE and is made by DSM. I would guess it is HDPE and the draw down a lot under heat so that the linear molecules become very well aligned.

As far as I know, it is not as strong as Aramid, but stronger than nylon. Also it does not plasticise in water. Vs Aramid:-
It is good in fatigue and compression.
It is better than Aramid to UV but still not good. It should be translucent.

Regards
Pat
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RE: What type of plastic line for this application?

(OP)
Thanks for all the comments here. To clarify, this is for permanent/semi-permanent use. This material will be threaded back and fourth through "eyes" a ways, so I won't really have to tie knots anywhere, and I'll have a somewhat more limited number of endpoints that need to be tethered down.


Kevlar
--------------------
I looked at it and was concerned about water absorption and loss of strength over time. I don't care if my line absorbs a bit of water, but if it absorbs water and increases in length by 5%, we could have a problem. I was also a bit off-put hearing some reports that Kevlar lost strength as it was used; references to firefighter escape ropes that could only be used once, etc.

(After living through several gnarly, catastrophic aluminum failures - thankfully not my design or my fault - I have become wary of any materials that include disclaimers about fatigue.)

I also didn't see any immediate sources of UV-protected, small lines. Everything I found was rope-like, rated for a thousand or more kg and just ridiculous from a size/cost perspective.

I am going to look into the Applied Fiber products, but I suspect they're overkill for my needs. In the meantime, I would welcome other supplier suggestions and clarifications to my concerns around load cycling and water absorption.


Fishing Line
--------------------
I can never get good data on performance over time (UV, embrittlement, elongation), or elasticity. Will this stuff break down in a few hours? Days? Weeks? Months? Or maybe it will just slowly elongate, resulting in eventual failure of my installation? (That's what would happen, should the line elongate too much. I'd be able to see this happening before I experience catastrophe, but it would be a huge hassle to deal with replacing this.)

It's possible that by knowing the material, I can nail these properties. The problem is that I'm not far enough into polymer production to know, with certainty, that anything that's nylon or UHMWPE is going to have a certain set of properties, and there's nothing (practically) in production that will cause said properties to be lost.

If somebody could educate me on these points, I'd appreciate it.


Other Materials
--------------------
Nylon: My primary concern is stretch/elasticity. I don't really need to tie a knot as long as tethering it to the endpoints isn't a big issue. The nylon lines I've seen in the past are amazingly close to invisible in water. Some grades of fishing line do claim to limit stretch: http://www.fishplatypus.com/products_lostretch.html

UHMWPE: I like the properties of this material, including incredible resistance to UV, chemicals, water, etc. though I'd expect it to be less transparent than nylon. I'm concerned about creep. I'm also concerned the incredibly low coefficient of friction could complicate tethering the endpoints.

Flourocarbon: I'm not exactly sure what material this is, but I'm guessing PTFE. I have similar concerns about creep and friction coefficient as UHMWPE. Several different fluorocarbon lines are listed here: http://www.hiliner.com/newimages/momoi.pdf


Conclusion
--------------------
So far, I have learned a bit more about materials, but I haven't tracked down any concrete data on the elasticity or creep of any of the materials in question.

I would appreciate any more concrete data anybody could point me to on these points...
 

RE: What type of plastic line for this application?

Dyneema and Spectra are two tradenames for UHMWPE fiber. You can read quite a lot about the material here...

http://en.wikipedia.org/wiki/Ultra_high_molecular_weight_polyethylene

I think that's worth considering for your application. It's used in rigging for yachts and high performance sails. It won't take up water and become softer, in contrast to nylon. You'll need to make sure you get a grade specifically made for outdoor use (they probably put in additives to protect against the UV light).

Its density is less than 1.00 g/cm3 so it will float on water. Not sure if that is desirable for you.


Chris DeArmitt

RE: What type of plastic line for this application?

(OP)
HPPE shows a creep of 1 x 10-2 per day at 20% load and 22° C. 0.01% per day. That means we'll see over 1% creep over 100 days. This is going to be an issue.

Unless we can show lower creep at lower loads, I don't think it would really be suitable.

Reading up on that book suggests aramid fiber might be better and makes me feel better about the load aspect of things. However, that still leaves me trying to find a source of unusually small, UV-protected armid line.

It would be nice to find some data on nylon and perhaps even PP.

FYI: density of the material doesn't matter for this use. Size doesn't matter either, within reason.

RE: What type of plastic line for this application?

Hello, what do you mean by HPPE? The material we suggested was UHMWPE (very different to PE and PP).

Aramid fibers are good for stiffness but I understand that they break without warning after multiple use. That's why they are not used for parachutes. You would need to be careful in the design and how they are used.


Chris DeArmitt

RE: What type of plastic line for this application?

Hmm.  Our needs for aramid fibers are as reinforcement fabric in diaphragms, in hot and cold water service.

As such, we avoid kevlar aramid, due to its strength degradation over time in water (hydrolysis).  We typically always specify nomex aramid fabric, as it has much better wet strength retention, even though its breaking strength is typically much lower than kevlar.  I've struggled to find a "generic" description for the difference between the two aramids, but believe the following excerpt from a report I wrote awhile back is correct:

"The Nomex fabric has been previously confirmed by test and research at XXX to outperform other polymers (e.g. polyester and Kevlar) in hot water.  The proposed knit fabric does not change the base polymer of the fabric reinforcement, only the method of construction (to knitted fibers instead of woven fibers).  Nomex is a trade name for meta-aramid polymer fibers, Kevlar is a trade name for para-aramid polymer.  It is recommended that the XXX spec. sheets for the fabrics used in our diaphragms should call out either para-aramid or Nomex fibers."

...but as always will bow to the smart folks here regarding the meta- vs. para-aramid distinction.

Far as I know, both kevlar and nomex fabrics are pale white to off-white (beige) in color, but can be dyed/colored darker.  Both will suffer strength loss with UV exposure, depending on the strength of the light source and duration of exposure.  A Dupont bulletin I received from them shows a 55% strength retention after 80 hrs. exposure to "accelerated UV degradation test (Xenon arc light) per AATCC Standard Test Method 16E".

 

RE: What type of plastic line for this application?

You are correct regarding meta- and para- designation of these tradenamed aramids.  Meta-, ortho-, and para- refer to branching from benzene rings.  If the branches are 180 degrees away, then the structure is para-.  If the branches are 120 degrees away, then the structure is meta-.  And, if the branches are 60 degrees away, then the structure is ortho-.     

Regards,

Cory

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RE: What type of plastic line for this application?

Aramid is no suitable for running around pulleys, which is a point you only just mentioned.

I stated earlier it is poor in compression. The inside surface when negotiating a pulley is in compression.

Aramid is used with success in very high performance sails. They will have aramid elements where the tension is greatest and where elongation reduces performance the most. The elements that require better fatigue and abrasion resistance but still high tensile and creep resistance are gel spun PE (Spectra or Dynema). The third element which makes up the lower laded areas is polyester.

Aramid is best in straight tension and will hydrolyse very slowly at the temperatures you quote. It is used extensively as the reinforcement in the hulls of high performance boats and in aerospace where it is only in tension and never in compression, BUT as you run through pulleys it is disqualified.

From the currently listed requirements, gel spun UHMWPE seems the go. They claim excellent UV stability which surprises me as PE is inherently quite poor to UV, so I expect they are adding a lot of UV stabiliser to it. If they simply mean it is good compared to aramid, that's not saying much. If it's good compared to nylon, then you will get a very long life outdoors. Stabilised nylon fittings last many years on the decks of boats and roofs of cars.

http://www.dsm.com/en_US/html/hpf/home_dyneema.htm
 

Regards
Pat
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RE: What type of plastic line for this application?

(OP)
Chris, regarding HPPE, that's what they're listing Dyneema under at the Google Books link. I'm assuming it's another term that encompasses UHMWPE.

As for UV and UHMWPE, I believe UHMWPE is fairly UV resistant. I'd guess they probably still would add something to improve this, but I don't think it's terribly sensitive as a raw material.

I'm concerned about the creep issues with UHMWPE. I'm not able to find much good data on creep. The question is how load and creep behave. I just can't have this line creeping a ton on me. I have no problem overdesigning, perhaps by a lot, so long as the raw material isn't exorbitant.

One bit of data I found here:
http://www.rigging.com.au/dynex1.htm

The chart for 40 mm rope shows essentially zero creep at 22 tf on a 40 mm SK75 fiber. The table they provide shows a minimum breaking strength of 119.8 tons on the same size rope. Thus that material de-rated by a bit over 80% has very little creep. Of course, I don't know whether this creep value would scale down to the sizes I would need.

Dyneema appears to have a SK78 grade just for dealing with creep, at least halving SK75's creep:
http://www.textileworld.com/Articles/2007/May-June/Departments/Quality_Fabric_Of_The_Monthx_Cutting_The_Creep.html

Unfortunately, finding smaller grade lines of dyneema is proving problematic. I am guessing ~3 mm is the largest I'd need.

Here's a 1.75 mm unspecified grade but only 400 lbs load:
http://www.leisurepro.com/prod/OSBDL17.html?ci_src=14110944&ci_sku=OSBDL17

A 3 mm grade, once again not well spec'd out:
http://cgi.ebay.com/1050lb-3mm-UHMWPE-Spectra-Dyneema-Cord-Rope-100ft-units_W0QQitemZ250297067065QQcmdZViewItem

Reality is, if we're talking about 25¢ a foot for this kind of material, I don't know that it's really viable for this application. We're now looking at the line being massively more costly than any other materials. Even 15¢ or 10¢ a ft is probably not acceptable. I'd really like a number more like 2-3¢ per foot for a minimally-creeping line that bears ~60 kg sustained load - maybe that's crazy impossible, though.

I think one major issue is that I have to design to such a low load value when working with a dyneema-type material to keep creep under control. If I didn't have to over-design by a factor of 5+, the cost would be a lot lower.

I'm starting to wonder if plastic lines are really what I should be considering here. I can deal with a little stretch in the line, if it's predictable based on load, but I can't deal with much creep.

It would be nice if I could get to the bottom of the question around creep and stretch on nylon, but I have yet to find solid numbers,

Nomex sounds like it could be viable if care was applied, as I'd be able to design a lot closer to spec without creep issues. However, I can't find anything near small enough.

Vectran is another interesting possibility. I've not heard anybody mention it, but it has unusually low creep it appears. The cost for larger ropes don't seem terrible, but I can't seem to easily find smaller lines.

Given that size is not an object, but cost is, I wonder if some other lower cost materials should be considered? Polypropylene? Even abandon polymers and jump to some kind of a metal cable?

As this particular application involves a lot of back and fourth of the line to secure the load, it would be possible to substantially reduce the length of line run, but proportionally increase the load, by using a material such as fiberglass to distribute the load. Of course, this would only be sensible if a low-load line was too costly.

RE: What type of plastic line for this application?


Like you, I'm beginning to wonder if plastics are the right way to go to meet your for your requirements (apart from translusceny/transparency).

In the UK we've used miniature stainless wire ropes like these:

http://www.tecni-cable.co.uk/Stainless-Steel-Wire-Rope-Cable-Fittings/Miniature-Stainless-Wire-Rope

 

Trevor Clarke. (R & D) Scientific Instruments.Somerset. UK

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RE: What type of plastic line for this application?

(OP)
Translucency/transparency is not an utterly absolute parameter, so metal is a possibility... if the cost can make sense.

RE: What type of plastic line for this application?

Finding creep data can be very hard, the measurements take too long and no-one wants to do them even though creep is an important cause of failure.

I have done some checking on creep stress versus yield stress. As a rule of thumb, if the stress you are applying to the polymer is less than 20-25% of the yield stress then there will be very little creep. Luckily data for yield stress is very common so that may be of some help to you in the absence of solid creep data.

It is estimates that 10% of all polymer part failures are due to creep. Source:

Polypropylene Definitive User´s Guide & Databook, Plastics
Design Library, New York, USA, 1998

Here is some data taken from a course I teach on polymers and composites.

     Creep Stress     Yield Stress
LDPE    2.1 MPa           8 MPa
HDPE    5.0 MPa          27 MPa
PP      5.0 MPa         25-34 MPa
ABS     6.3 MPa          48 MPa
uPVC    10-12 MPa        50 MPa


Chris DeArmitt

RE: What type of plastic line for this application?

The Gel spinning process greatly reduces the creep, so you cannot compare normal extruded rod to gel spun HDPE or UHMWPE. I believe the difference in the Dynema/Spectra yarns vs normal PE yarns is the spinning process rather than the base polymer grade. The gel spinning process results in VERY highly oriented VERY crystalline micro structures. A very long linear base polymer molecule obviously also helps. Terms for PE like UHMW or HD re arbitrary and relative.

I have a lot of data on creep of aramid fibre and I know it is very low as it has to be for use as the central strength member in aerial optical fibre cables. A gel spun PE competes with araid in support cable and reinforcement applications,I would be astounded if they did not have similar data.

CONTACT DSM direct. Contact the head office of the Dynema division in the Netherlands. They will have the data. Call them.They will speak excellent english.
 

Regards
Pat
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RE: What type of plastic line for this application?

Have you considered carbon fibre? I am not familiarised on it being used on its own, but perhaps would meet most of your requirements. Not the translucency, of course, but I doubt any of the proposed, except Nylon will.

I think Dyneema might be a material to look into, as well. I totally agree with Pat regarding contacting DSM.
UHMWPE is used in prosthetics, for hip-joints replacements, and, genearlly this type of prosthesis is aimed to last 10/15 years. And it has to survive the amazingly hostile environment in the body, which includes the frequent and, some times prolonged loading of the parts.

Concerning strain, it is really convenient that you aim for very low values, because polymeric fibres contain highly orientated molecules and won't "give in" much.

I don't know the application, but it might be more cost effective to go for a cheaper material, but sell the product at a cheaper price. Not so environmentally friendly, but might be better.

But if you want to achieve such a low material cost,  metal, as SincoTC mentioned, should be considered. For that you would have to check if the pulley system materials would be able to cope with metal. If the metal string went through plastic rings, youo would have a problem.

By the sound of it (particularly the translucent part), you want a fishing line for medium-sized fish. :]

"Ask DNA"

RE: What type of plastic line for this application?

A friend of mine did a post-doc on UHMWPE for hip joints. They radiation cross-link the material to give the good creep resistance. That's actually a pity as it degrades the PE.


Chris DeArmitt

RE: What type of plastic line for this application?

(OP)
Thank you for the constructive replies.

I'm really interested in carbon fiber. I think it may have just the properties I need. The applications I've seen it used in all would seem to specifically rely on its unique creep resistance and strength.

I'm going to look into carbon fiber further, as I know I have seen even fabrics and whatnot made of it, so I suspect it may be quite cheap.

For the moment, I'm setting Dyneema aside. Contacting the maker may help with some data, but Dyneema seems a bit expensive even if the creep values were significantly improved over lower quality products. If carbon fiber proves a dead end, I'll come back to Dyneema.
 

RE: What type of plastic line for this application?

Being subjective: Carbon fibre is awesome. :D

I don't actually know monetary values, but I think Patprimer might know a bit. But it should be expensive.
As carbon fibre is used a lot on composites, I suggest for you try the composite engineering forum in this website.
Just a small comment: There are several types of carbon fibres (High strength, high modulus, etc), so you should bear in mind this.

there is another fibre yuo can try, which is a PU. I can only remember one of the commercial names, which is M5 (developed by Magellan and Dupont), but there was anotehr brand. Maybe our materials experts know it.
The problem is taht it is not wide spread and it is expensive. :D
Ye, I know...Not much help. At least you get to know another high-performance fibre.

Still regarding Dyneema, perhaps yu should use concurrent engineering ( :D ) and contact DSM, while looking for alternatives.
 

"Ask DNA"

RE: What type of plastic line for this application?

Aramid, Carbon and Gel spun PE are all quite expensive. I am out of date, but carbon was the most expensive and gel spun PE as the cheapest, but hings can change a bit over 10 years.

Carbon is generally classified as carbon or graphite. Graphite is the mor expensive and from memory has the highest modulus.

Regards
Pat
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RE: What type of plastic line for this application?

Man, how old are you Pat?

I am not quite certain if nowadays carbon is still the most expensive, due to the increase of capacity.
I know the price peaked a few years ago (maybe between 2003-2005), because of Airbus and Boeing.

There are several E-moduli for carbon fibre. The most common is about 230GPa (all you americans fetch a converter), but you can get as high as 900 something GPa. But, of course that strength and strain suffer.

http://en.wikipedia.org/wiki/Carbon_Fibre
It contains a few suppliers, as well.

 

"Ask DNA"

RE: What type of plastic line for this application?

(OP)
I am trying to find some prices from a distributor or online retailer and not having a lot of luck. I'm finding tons of fabrics, but not cords/ropes/lines.

I want to just buy a moderate amount (a few thousand feet at most) at first, so I'd prefer not to try and deal with the manufacturer quite yet.

Anybody have ideas on who might sell it directly?

Pat, the primary motivating factor for carbon fiber from my view is that it should have drastically lower creep. This means I will need less of it than other materials where I need to design to a tiny fraction of capacity to avoid creep issues.

I also came across fiberglass cords. I wonder how they do with creep?
http://www.davlyn.com/products/product.php?id=3&gclid=CNO85of6spcCFQQRswodtVRYjQ
 

RE: What type of plastic line for this application?

I've suggested your best course of action in my opinion. You choose not to do that. I can't help any further.

Regards
Pat
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RE: What type of plastic line for this application?

(OP)
Pat,

I'm appreciate all the effort you've put into generating suggestions, and I'm not trying to devalue your advice. I just need to find time during business hours to contact the local DSM office, hence my not trying delve into it further online. I have an email pending to DSM, but I have not heard back yet.

I have wondered about Zylon, a thermoset polyurethane similar to various aramids in terms of strength it seems. I can't find a lot of data on the cost of this product.

I was eyeing up polypropylene and polyester ropes and noted that 1/4" ropes can be head for under $0.04/ft in roll quantities at retail. Their safe working load looks to be suitable.

Of course, this is pretty huge stuff for such a small load versus what might be possible with other materials. UV tolerance may be an issue with PP, and creep has to be resolved, are there any other reasons I should not consider PP?

Polyester also seems promising, it is considered to not stretch. I don't know about creep, however. UV appears not to be an issue. Are there any other reasons I shouldn't consider polyester?

Chris, you posted some nice numbers on creep stress. Can you give me an indicator as to how to apply the numbers?

Are these numbers that represent a threshold below which there's no creep, or simply a number that represents a creep of a certain amount?

     Creep Stress     Yield Stress
LDPE    2.1 MPa           8 MPa
HDPE    5.0 MPa          27 MPa
PP      5.0 MPa         25-34 MPa
ABS     6.3 MPa          48 MPa
uPVC    10-12 MPa        50 MPa  
 

RE: What type of plastic line for this application?

Hi guys.

First, Pat I didn't mean to be disrespectful. I surely would like to have the knowledge you have on materials.
Do you deal with natural fibres?

I am not really certain about distributors/retailers for carbon fibres.
Generally, you can find yarns of carbon fibre as they are used for Filament Winding process.
if you don't a awful lot, perhaps you can ask the manufacturers for samples.

As I mentioned before, you should consider asking these questions in the Composite Engineering forum in this website.

Blue&white: The M5 fibre I mentioned is similar to Zylon and, I actually wanted to name the latter.
Similarly to M5, you should have a lot of difficulty in finding data for the material.

PP and PET will always creep. And I believe they would  more creep than Dyneema, for instance.

Creep stress should be the stress value at which below of it you would not see any creep.  

"Ask DNA"

RE: What type of plastic line for this application?

Quote:

I've suggested your best course of action in my opinion. You choose not to do that. I can't help any further.

If this was seen as a hissy fit by me, it is not. It is a simple statement of fact with no intention to imply emotion

I am 61 years old and once again I consider my age a simple fact and attach no emotion to the number.

My initial study and work was in the textiles industry in colour application, but I soon moved to the plastics industry. I eventually reached a position where had some responsibilities for both plastic, apparel and high tech yarns. This was with Akzo Nobel and DSM. I have not ben involved with yarns or Akzo Nobel since 1995 nor DSM since 1997.

My experience with natural fibres stopped in 1977, although I ecxpect they have not changed much.

Regards
Pat
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RE: What type of plastic line for this application?

Right, the creep stress is the stress below which there should be "no" creep. In reality there is likely to be some creep at almost any stress if you wait long enough but for practical purposed you can ignore it.


Chris DeArmitt

RE: What type of plastic line for this application?

Wow Pat. Congratulations in the sense that most senior (wiser) people don't generally use the internet, at least for fora.
I did Polymer Engineering and at (and before) the first year of my degree I wanted to go and work for Dupont (because of the high performance materials, such as Kevlar). After changed my mind, as , among several other reasons, I would not like to move to the US.

I think we left out glass fibre from the spectra of choices. Blue&white: you should be able to get plenty of info on these.

Chris: I left out that part, because blue&white seems a bit paranoid about creep. hehe

Nuno
 

"Ask DNA"

RE: What type of plastic line for this application?


NunoH: I hope you are not taking the p*ss from your elders..

I am older (but not much wiser!) than Pat..

Your desire at one time to work for DuPont (grey suit, shiny brown shoes) gives you no Brownie points at all on this forum.

Respect your elders - for we have been there, done it, smoked it and got the scars to prove it.


Harry

ps: Any idea how to set a moulding press up on a new tool?

RE: What type of plastic line for this application?

Harry: No, I wasn't taking the piss. I was merely saying that I was positively surprised.

I don't see how the desire to work for a particular company would give any points.
As Pat described a bit his background, I felt impelled to do the same.
So, Dupont personnel is a bit like the US federal agents, wearing "standardised suits"?

I do hope you guys stay about, because, as I mentioned in Pats case, I sure would like to have his knowledge on materials, although 1/5 would be very nice already.

Regarding your question, I am afraid that I cannot be much help. But, I would suggest for you to open a new thread with the matter and further explain a bit more.

"Ask DNA"

RE: What type of plastic line for this application?

"ps: Any idea how to set a moulding press up on a new tool? "

Put tool on floor.  Lift press and place on top.  Go have a beer and celebrate.

Or am I missing something?

Harry, do you shoot compound bows?  Been looking into making an acquistion of a couple for awhile now.  Next you'll tell me your company molds them, and I can purchase the parts cheap from you on ebay.  Speaking of which, I still owe you some photos from a kayak trip I took awhile back, have not forgotten, just seem to never have time.

RE: What type of plastic line for this application?

Apologies to the op - this is degenerating completely off topic (again).


Ben:

You forgot stage 1: Put on support truss. And you missed the "s" off beer!

Bows, afraid we don't mould them! Just bought 2 (USA/Browning Micro Midas') for the kids. Fancy one (adult) for myself though, but might treat myself to a traditional English longbow for xmas firstly. http://www.bickerstaffebows.co.uk/proddet.php?cat=Standard&prod=5


Photo's would be nice but no rush...hope blades were ok.

Harry



 

RE: What type of plastic line for this application?

:) Beers...mmmm.

Blades worked extremely well, we (well, really, me) kept up with the guys with fancy carbon fiber shafts (but smaller area blades) quite nicely.  And when we raced...well, we kicked everybody else's butts; the bigger blades could really dig in, and the two-man shell is just more hydrodynamic than 1-man shells, methinks.

RE: What type of plastic line for this application?

(OP)
Thanks for all the information, everybody!

I am still trying to get ahold of all these possible suppliers to track down the exact data, pricing, etc. on everything but I will report back when I reach a conclusion.

RE: What type of plastic line for this application?


blue and whiteg3:

Please do report back - it will be appreciated I am sure. (Not many do!)

My wife always says to report back when I have reached a conclusion, but she may be referring to something else...

Cheers

Harry  

www.tynevalleyplastics.co.uk

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