Fuselage side bending question

[CdnMedic]

Im fitting up my fuselage sides on my 2L.
Thinking ahead to the next step of bending the sides inwards, I'm concerned with the horizontal tube that the rear spar attaches to.
When I go to bend the longerons, that horizontal tube has to either be bent along with them if it is tack welded in to place, or I don't have it tacked in to place and place it in once the sides are bent. Since the tubes it attaches to are at an angle, if I pre-fit the tube when the sides are flat on the table, the cope will change and will no longer fit.
So, is it best to just heat it up in line with the bend location of the longerons when I go to do the bend?

The bend line is vertical with the red-blue arrows shown, and you can see the horizontal tube in question.

 

[proppastie]

Difficult to answer with information given unless one is familiar with the structure in which case any 2L builder that is past this point will be able to answer better.
If there is a user group or plans vendor this question should be mounted there.

 

[CdnMedic]

Difficult to answer with information given unless one is familiar with the structure in which case any 2L builder that is past this point will be able to answer better.
If there is a user group or plans vendor this question should be mounted there.

This is our user group for the Sonerai since we lost sonerai.net.
Our plans vendor is not very useful, they sold me plans with some obvious mistakes that weren't caught until I built the components as per the plans. They basically said I was SOL for the time and money wasted.

 

[TFF]

I would pick red arrows where I would want to bend it, but that’s me. A lot of designs leave the nesting a bit loose like at blue to facilitate angle changes. I bet if you looked at 20 planes, you would see multiples of each version. Plans built is about making these choices. Subtract all the RVs and other prefab kits and this is what everyone has to contend with.

 

[proppastie]

This is our user group for the Sonerai since we lost sonerai.net.

Oops...did not notice the Forum title in the post.....hopefully there is someone here that can help you.

 

[BJC]

I would bend it up from flat on the table. I would start the bend just aft of the clusters at the red arrows. Then fit the cross pieced and the cross-diagonals. Once the cross pieces at the bend line and the tail post have been placed, it is easy tho true up the bends, if necessary. Some people overestimate the accuracy required. The bending is easier to do by having two heating torches and assistants.

Never been in a Sonerai, but the several aircraft in that general size range that I have been in all benefit from displacing the upper cross fuselage tube at the seat back area by curving the tube back or having two offsets in it to make for a more comfortable seating angle.


BJC

 

[soneraifred]

The intent of the drawings is to bend the fuselage sides at your two red arrows. I would install the horizontal rear spar support tube after the bending is complete.

 

[CdnMedic]

The intent of the drawings is to bend the fuselage sides at your two red arrows. I would install the horizontal rear spar support tube after the bending is complete

Thanks, you are who I was hoping to hear from.
I did see in the post where I got that picture from you suggested the red and blue line.
If I go red-red (which I did find matched with the plans) the longerons will lift up off the table. The manuals (or maybe it was the newsletter) mention that happening on the stretch specifically but not the original.

That would also change the vertical positioning of the horizontal stabilizer spar.

This is the bit of the blueprints that indicate the bend is at the red-red arrows... I'm tempted to go red-blue to keep the longerons flat.

 

[soneraifred]

The Sonerai II Original used the red-blue line, and that’s the way I built mine, which does keep the top longeron flat. It makes it easier to assemble the fuselage cross-members when the fuselage is upside down on the build table.

 

[CdnMedic]

The Sonerai II Original used the red-blue line, and that’s the way I built mine, which does keep the top longeron flat. It makes it easier to assemble the fuselage cross-members when the fuselage is upside down on the build table.

Ok, I'll follow along with what you did. Simplifies things for me.

For some reason that page in my plans has 2 different stations for the bend that coincide with the clusters at red and red and I do have the 2 original plan set...
But, I'm also the guy that found all of that improper info for the spar box in my plans, so who knows what other surprises my plans will have.