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Old 09-06-2020, 03:22 PM
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multiweb (Marc)
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Any material/mechanical engineer here?

What type of material (flat washer) would potentially give back ~3kg of pressure over an area of 1 square centimeter when compressed by ~1mm and come back to its normal thickness while reasonably keeping its elasticity properties within a temperature range of let's say 0c to 20c?

Rubber? Cork? Plastic?

TIA.
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Old 09-06-2020, 03:58 PM
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Neoprene.
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Old 09-06-2020, 04:04 PM
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Neoprene.
Thanks David. Like water taps seats?
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Old 09-06-2020, 04:34 PM
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sort of, neoprene sheet can be cut to suit.
Some hi temp silicone would work as well
https://au.rs-online.com/web/p/silic...E&gclsrc=aw.ds
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Old 09-06-2020, 05:03 PM
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Quote:
Originally Posted by DavidU View Post
sort of, neoprene sheet can be cut to suit.
Some hi temp silicone would work as well
https://au.rs-online.com/web/p/silic...E&gclsrc=aw.ds
Those sheets are a bit costly. Would that work? https://www.bunnings.com.au/zenith-1...-pack_p2400051
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Old 09-06-2020, 05:26 PM
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Thumbs up

yep
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Old 09-06-2020, 05:41 PM
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yep
Cool - got a pack tonight from Bunnings and will try. Thanks David.
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Old 09-06-2020, 05:56 PM
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One more question David, if I was to stack two would I get twice the travel and the same elasticity or less stiffness?
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Old 09-06-2020, 06:05 PM
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You would have to try it, generally this type of compression is a type of logarithmic function
https://courses.lumenlearning.com/wa...hmic-function/
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Old 09-06-2020, 06:23 PM
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You would have to try it, generally this type of compression is a type of logarithmic function
https://courses.lumenlearning.com/wa...hmic-function/
ha ok... I vaguely recall seeing that type of graph when stacking belleville washers. Will look into it. Thanks.
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Old 09-06-2020, 07:11 PM
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Hi Marc

Do you live in, or near to, a marine environment - if so, have a look at the attached file.

Cheers

Dennis


EPDM washers link:

https://www.bunnings.com.au/zenith-2...-pack_p2409517

EPDM stands for Ethylene Propylene Diene Monomer, a synthetic rubber used in a range of applications. EPDM is used most commonly used in the automotive and construction industries for various seals due to its excellent resistance to environmental factors such as Ozone, UV and general weathering.
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Old 09-06-2020, 08:16 PM
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Hi Marc

Do you live in, or near to, a marine environment - if so, have a look at the attached file.

Cheers

Dennis


EPDM washers link:

https://www.bunnings.com.au/zenith-2...-pack_p2409517

EPDM stands for Ethylene Propylene Diene Monomer, a synthetic rubber used in a range of applications. EPDM is used most commonly used in the automotive and construction industries for various seals due to its excellent resistance to environmental factors such as Ozone, UV and general weathering.
Thanks Dennis. I'm ~35km from the coast so no issues with salt (yet) I saw those in the same aisle as the ones I bought in Bunnings. The way I did the mod I can go back to the way the mount was if it's not working and I can also change the material used so will do some testing tomorrow. Just finished filling the holes. All drilled and tapped. Will post some pics tomorrow. Did the DEC only. RA backlash doesn't matter as much as the worm is always loaded.
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Old 10-06-2020, 09:44 AM
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Here's the idea. Like a crumple zone to stop binding and eliminate backlash. Got room for other material or belleville washers or small wave/disc/coil springs. Whatever will work. But I like the idea of the neoprene if it's elastic and comes back after compression over a hard spot. Also need to check if this will have any impact on guiding once the clouds clear. I can easily go back to previous mount operation as I used an existing hole.
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Last edited by multiweb; 10-06-2020 at 11:04 AM.
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