Honeycomb cell size affect on radius of curvature of cylinder

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Honeycomb cell size affect on radius of curvature of cylinder

Author	Message
Tim Ane	Tim Ane posted 4 Years Ago HOT Topic Details
Group: Forum Members Posts: 14, Visits: 107	Hi everyone, I am working with aluminum honeycomb structure to manufacture 2 meter diameter cylinder. my question is how cell size ore core density affect the formation of curved surfaces like cylinder? i am using overexpaned core for cylinder and confused in the selection of cell size. Is there any literature about honeycomb cell size affect on radius of curvature?
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Rosta Spicl	Rosta Spicl posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 54, Visits: 250	For your imagine, panel R1100mm contains AL honeycomb HEX 9mm, THK 5mm. I don't know about the rules cell size vs. bend radius.
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oekmont	oekmont posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	That's a simple geometry problem. If the cell size (along the radius) on the outside is x the cell size will be 1995/2000x on the inside. Given the diameter and the core thickness.
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Tim Ane	Tim Ane posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 14, Visits: 107	+x Rosta Spicl - 10/26/2020 11:45:17 AM For your imagine, panel R1100mm contains AL honeycomb HEX 9mm, THK 5mm. I don't know about the rules cell size vs. bend radius. Thank you for guidance. Did you used overexpanded aluminum honeycomb core for curved surface? Did you used bonding film to bond core and face sheet? If you have used bonding film, what is the material or common name of bonding film compatible with aluminum honeycomb core and carbon fiber prepreg?
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Tim Ane	Tim Ane posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 14, Visits: 107	+x oekmont - 10/26/2020 12:23:36 PM That's a simple geometry problem. If the cell size (along the radius) on the outside is x the cell size will be 1995/2000x on the inside. Given the diameter and the core thickness. Thank you for the time. but I did not understand. Can you elaborate more?
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Rosta Spicl	Rosta Spicl posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 54, Visits: 250	+x Tim Ane - 10/27/2020 4:48:04 AM +x[quote] Rosta Spicl - 10/26/2020 11:45:17 AM Both, HEX or OX, it depends on surface complexity and required rigidity properties. OX offers different rigidity depends on cells direction. I much more like use Rohacell, because there is a possibility to 3D shaping very easily. Yes, on 2-shot process use self adhesive film, but lately often I use RG 5min epoxy glue, coat the surface using spatula, wait for geltime - tacky surface and apply core and next plies. Then standart curing process in oven, resp. autoclave. If I have pre-cured carbon skins, or AL skins, I use standart laminating epoxy + microballons to make tixotropics compound, coat the skins, vacuuming, curing at RT.
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Tim Ane	Tim Ane posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 14, Visits: 107	+x Rosta Spicl - 10/27/2020 9:29:32 AM +x Tim Ane - 10/27/2020 4:48:04 AM +x[quote] Rosta Spicl - 10/26/2020 11:45:17 AM Both, HEX or OX, it depends on surface complexity and required rigidity properties. OX offers different rigidity depends on cells direction. I much more like use Rohacell, because there is a possibility to 3D shaping very easily. Yes, on 2-shot process use self adhesive film, but lately often I use RG 5min epoxy glue, coat the surface using spatula, wait for geltime - tacky surface and apply core and next plies. Then standart curing process in oven, resp. autoclave. If I have pre-cured carbon skins, or AL skins, I use standart laminating epoxy + microballons to make tixotropics compound, coat the skins, vacuuming, curing at RT. what is the panel (honeycomb core) thickness and you have used 9 mm cell size so strength is compromised in favor of light density core? Did you find reduced strength in your case? Can cylinder be formed with hexagonal honeycomb core in place of OX?
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Rosta Spicl	Rosta Spicl posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 54, Visits: 250	+x Tim Ane - 10/27/2020 10:45:18 AM +x Rosta Spicl - 10/27/2020 9:29:32 AM +x[quote] Tim Ane - 10/27/2020 4:48:04 AM +x[quote] Rosta Spicl - 10/26/2020 11:45:17 AM The core is 5mm thickness + 2x 1mm skins. I can't say strictly the smaller cell size causes much more strength and rigidity, probably yes a little bit, but I can say much more load resistance and impact resistance...and a little bit weight increasing of course. At the panel above the impact resistance was the crucial, I used aluminium skins instead laminated. The AL price was much more lower than kevlar. From my point of view, on R1000 no issues with honeycomb cell size 5-10mm. It's up to you, depends on what you want to have...
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