Primary Member: Firewall

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    Hello, quick question. In regards to designing the frame, more specifically the firewall tubing. Can the sides and top of the firewall be all one piece of tubing with multiple bends? If you look at the key-points for the primary members in the rulebook, my question is: can one tube be welded on to the bottom member (AL to AR) and go through SL, BL, BR, and SR or will that break the rule of "Straight members may not
extend longer than 1016 mm (40 in.) between Named Points or comply with Rule B.3.2.4 - Additional
Support Members". 

Please let me know if I need to rephrase my question. Thank you

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krlindgr Members Profile Send Private Message Find Members Posts Add to Buddy List Double Secret Probation Joined: Jul/27/2020 Status: Offline Points: 3	Post Options Post Reply Quote krlindgr Report Post Thanks(0) Quote Reply Topic: Primary Member: Firewall Posted: Jul/27/2020 at 7:28pm
	Hello, quick question. In regards to designing the frame, more specifically the firewall tubing. Can the sides and top of the firewall be all one piece of tubing with multiple bends? If you look at the key-points for the primary members in the rulebook, my question is: can one tube be welded on to the bottom member (AL to AR) and go through SL, BL, BR, and SR or will that break the rule of "Straight members may not extend longer than 1016 mm (40 in.) between Named Points or comply with Rule B.3.2.4 - Additional Support Members". Please let me know if I need to rephrase my question. Thank you

Derrick lr Members Profile Send Private Message Find Members Posts Add to Buddy List Double Secret Probation Joined: Dec/09/2019 Location: Montana, USA Status: Offline Points: 4	Post Options Post Reply Quote Derrick lr Report Post Thanks(0) Quote Reply Posted: Jul/27/2020 at 8:37pm
	If I'm understanding your question correctly, the answer you're looking for is in your post. The rules, specifically B.3.2.1 like you quoted, state that the max length for straight members between named points is 40 in. and combining it with a sentence later in the same rule: "Small bend radii (<152 mm or 6 in.) that terminate at Named Points are expected, and are not considered to make a member bent, regardless of angle." should help to clear things up for you. As long as the bend radius of the bend at each named point it passes through is under 6 in., then the bend effectively becomes that named point. In short, the firewall can certainly be made out of only 2 sections of tubing, so long as you design the bends to be at the named points and use a small enough bend radii. Refer to Figure B-8 of the rear roll hoop in the rules for a better idea of what I'm describing. Is that what you were asking about?