Ebike frame design - strong enough?

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Ebike frame design - strong enough?

Author	Message
Peteo	Peteo posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 3, Visits: 37	Thanks for the reply, scottracing. I have some CF tube from HobbyKing (which I was using for another project) and wondered if their tubes - which are 20mm square, with a 1mm wall - would be suitable to build a lugged frame from. My plan is to bond these lengths together beforehand so that the frame would, effectively, be made of 40mm x 20mm tubes (as shown in the image attached). I'd then bond to the overall frame whatever flat UD cloth layers are required to make it structurally sound. I wanted to check if this is possible? Attachments tubes2.jpg (517 views, 8.00 KB) Edited 8 Years Ago by Peteo
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scottracing	scottracing posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	bike frames commonly use UD for most of the construction, carbon does not like compression at all what spec of CF are you using in the tubes? The use of bonding metallic parts into the tube is how most frames are constructed but you need to ensure the surfaces are properly abraded and cleaned to get a good bond.
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Peteo	Peteo posted 8 Years Ago HOT Topic Details
Group: Forum Members Posts: 3, Visits: 37	Hello. Newbie here. I’ve designed a front frame for an electric bike in Fusion 360 and I’d like to build it. My concern is frame strength and rigidity and I wonder if anyone can comment from the specs I have... The front frame is a triangle made from lengths of 20 x 20mm CF square tubing (woven with a 1mm wall thickness) which I have. I will structurally bond together two sections of this tube for each length required (ie, creating 40 x 20mm double-tube - the shorter sides being on the bike’s sides). I want to join these lengths into the triangle shape by bladder-moulding internally-fixing ‘lugs’ (ie, lugs with male plugs to insert into the hollow straight tubes and structurally bonded. The lugs will contain the fixings for peddle crank shaft, rear swingarm etc. I’d like to retain the angular form of the tubes and lugs but I wonder if I need to add extra layers of CF fabric onto the finished triangle (eg, unidirectional) to make the bike strong enough to use. Any comments, much appreciated.
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