Injection Molded Gutter Components 3

[Byrd74]

I am in the process of designing gutter end caps and gutter brackets. The bracket is attached inside the gutter and has a hood overtop to keep leaves from going into the gutter. Currently I am looking at PA 66 +20%GF for the bracket and PA66 for the end cap. As you can imagine it is a little pricey so I want to get some suggestions on alternatives. The bracket will need to be rigid due to supporting a load and be able to withstand the temperature swings anywhere in North American. The endcaps need good UV resistance. I would also like to have the option of painting the endcap or add color to the material. Just not convinced yet that adding the color to the material is a good idea due to fading. The gutters are aluminum and the endcap and bracket will have a few screws and caulking put on it during assembly. I noticed from other threads that ASA seems like a good option for the end caps but I am not sure if it can be painted? Thanks in advance for any recommendation on material or pitfalls!

 

[patprimmer]

Both ASA and PVC can be painted quite successfully.

They can both also be coloured during moulding.

PVC is somewhat more economical and while quite good to UV when stabilized it is not so good as ASA.

If the paint used is UV opaque, it can offer perfect protection so long as it remains intact.



Regards
Pat
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[Byrd74]

Thanks!
What are your thoughts on ASA for the bracket. Can GF be added to ASA for strengh?

 

[Pud]

PA6 has virtually the same mechanical properties as PA6.6, and it's much cheaper.

Never seen GF ASA, but I guess someone will make it for you given enough call off.

Agree with Pat re PVC, but it's getting a bit of a no-no in some territories.

If you are going to paint it, you may as well use GF ABS (which is available "off the shelf")

Cheers

Harry

http://www.tynevalleyplastics.co.uk

 

[patprimmer]

I would stick with GF nylon for the bracket. I tend to have a prejudiced to specify nylon for general purpose load bearing applications due to cost effectiveness and no nasty surprises and a long track record of success in such applications.

Pud is right that type 6 tends to be cheaper, but that depends on when and where to some extent. Even in regions where they are similar in price, type 6 is considerably easier to mould.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[Demon3]

Indeed, there is no mention of GF reinforced ASA at

http://www.matweb.com

There is no point using ASA if you will paint it. ASA has the same mechanicals as ABS but at twice the price because ASA can withstand years outdoors and keep good properties and constant color. If you are going to paint it then you will get the same performance out of ABS at half the price because the paint blocks the UV light and protects the ABS.

It makes sense to use ASA when you add the color directly to the ASA (e.g. car mirror housings, siding) because then you can save money by skipping the painting step.

Chris DeArmitt

http://www.phantomplastics.com

consulting for the plastics industry