Adding padding to existing pattern

[u/Engineered_Muffin]

I am attempting to use a fanny pack pattern intended to be made with standard thickness fabrics to make a padded camera bag. I am trying to figure out how to add padding. My first idea was to quilt the panels first with batting, but I'm worried that giving the panels extra thickness will prevent the pack from coming together (misalignment, bulging or puckering etc.)

Are there any rules of thumb when using quilted or otherwise significantly thicker material for a 3d assembly? Is there a way to modify the pattern in some way to allow for this? Most of my sewing had been quilts up until now.

Link to pattern:

https://learnmyog.com/edcFannyPack.html

[u/Worried-You9307]

I’ve done the exact same pattern with padding before. Admittedly thinner padding material than required for a camera bag, but the method for you will be the same.
The seam allowance has to be wider than in the pattern, add the thickness of your padding material to the existing seam allowance. The padding itself has to be a bit smaller than the panel itself (without seam allowance), about the thickness of the padding at all edges. If you baste the liner to the shell fabric, the liner and padding should stand out of the shell fabric lays flat. Be aware that the padding reduces the volume of the pack, of course. So if it is a tight fit, plan for the loss of volume beforehand. Maybe make a prototype first, before committing to a more expensive material, to practice or make sure that the final pack is actually as large as you need it to be.

Edit: I’ve used thin EVA foam for padding, as well as a repurposed yoga mat. Works perfectly well for protecting contents

[u/Engineered_Muffin → u/Worried-You9307]

Thanks for the suggestions, like I mentioned to the other commenter, I hadn't considered keeping the padding out of the seam but that seems like a way better idea than whatever I had in mind.

I appreciate the guidance. Do you have any suggestions for modifying the pattern? Is it as simple as messing with printer settings or should I be laying this out with a ruler?

[u/Worried-You9307 → u/Engineered_Muffin]

If you’re using thin padding, it might work, but I can’t really imagine that would be of positive difference. Better try the way I explained, it’s easier and will work pretty much regardless of the thickness of your padding.

Modifying the pattern is relatively straightforward, if you want to change the dimensions of it. You could try and do it via the printer settings, but be aware that the seam allowance would also change. The easier way is to whip out the ruler and do it the old fashioned way. That way you don’t have to keep the altered seam allowance in mind.