Why holes in formers?

[Swampfox]

I've built pretty much FG models because I like them and I think they suit my abilities.

Since I joined this group I see many models, almost all aircraft, that are constructed using 'formers', kind of like bulkhead structures, many with holes of various sizes cut through them.

I've followed a couple of build threads and it appears that the main use for these holes is that they make a convenient grip. I've seen some builders route their rigging through them.

Is there any other use for these holes? Anything else I'm missing here? If I build a model with these formers and I don't cut the holes is that a problem?

Thanks,
SFX

[rickstef]

check this link Holes in aviation frames?

[mbauer]

SFX,

Not sure about the other designers, but weight reduction for flight, in my models.

Mike

[SJPONeill]

No problem but makes life harder...

The holes are there for three reasons:

To stick your finger in to manouevre the former in the skin tube.

To let to reach in with small fingers and tools to burnish the inside of a join.

To reduce weight in some more delicate models...

[Ron40]

Swampfox,
These holes are primarily called finger holes. They aid in installing
the former into it's location in the fuselage section. You do not
have to cut them out. However they do need to be removed if say
they are just behind the area where the prop wire or prop rotation
dowel would interfere due to it's length. They also give access to
the inside area of the fuselage section. Ron

[peter taft]

The guys tell you right... if you have a former that is one that has NO cut-out {some don't - depends on structure} i usually glue a few extra tabs to the flat surface so that i can use tweezers on them to PULL the former into place - when dry, cut them off again.

[rockpaperscissor]

Holes in formers are great for larger scale aircraft - 1/33rd etc. But in small scales their use is limited. In my 1/72 builds that make use of formers, I just cut a slit to accept a screwdriver, and install/manipulate the former as needed by twisting the screwdriver. I first saw this technique on this forum - maybe one of goldenbear's aircraft build threads? Anyway, it works very well for small scale models.

[bagpiper]

Originally Posted by peter taft

The guys tell you right... if you have a former that is one that has NO cut-out {some don't - depends on structure} i usually glue a few extra tabs to the flat surface so that i can use tweezers on them to PULL the former into place - when dry, cut them off again.

Originally Posted by rockpaperscissor

Holes in formers are great for larger scale aircraft - 1/33rd etc. But in small scales their use is limited. In my 1/72 builds that make use of formers, I just cut a slit to accept a screwdriver, and install/manipulate the former as needed by twisting the screwdriver. I first saw this technique on this forum - maybe one of goldenbear's aircraft build threads? Anyway, it works very well for small scale models.

Now there's a couple of splendid ideas. Thanks for sharing.

Cheers
Jim

[Lex]

Making things clear, this is needed most when there are spanwise formers only and are installed AFTER the skin is formed into a cone. With intersecting formers in both lengthwise and spanwise directions the skin is usually applied last so holes are not found on this type of design.

[rbeach84]

Not to be discounted is the effect of 'airflow' to both sides of the seam. I like the holes because it allows me to reach in with the ol' burnishing tool and press the seams from inside while supporting from the outside. Plus, I can often re-establish my pre-formed 'compound curvature' which tends to flatten out when applying the skin to the former (I know, that is "backwards" from the usual practice.)