A Question about Bracing and other warping-preventables

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x30ffx

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As I assembled my first pep out of cardstock, the model came together, but ended up being badly deformed at places. I'm not quite sure how to maintain its integrity and structure, but bracing seems to be best.

I'm working from Flying_Squirl's Mark VI helmet model, which comes with bracing. At seems to be extremely important in the resin stage, but has it any use for the assembly stage?

Should I install the bracing before or after everything is assembled?

Thanks!
 
Make sure you are using thick enough cardstock.

If it's warping before you've even added a layer of resin then you've gone wrong somewhere. Don't make the folds by hand, score the lines with a blade or go over the lines a few times with a pen to get perfectly straight folds. What glue are you using?

Depending on how badly warped it is, it might be possible to save with filler. As for bracing/support struts, you can quite easily make some yourself, they don't need to be part of the pep file, just cut some strips of cardstock and fold them longways, and adjust the size until it fits the piece.
 
Since cardstock is relatively flexible, the bracing basically adds more rigidity to the piece and makes sure certain distances are correct (such as the width of a helmet at certain points). It should be installed while it is still cardstock, then, once a couple of layers of resin (or whatever initial hardening technique you are using) has been applied and the piece is more rigid and better able to hold its shape, they can be removed and fibreglass (or an alternative secondary hardening technique) can be applied safely without the piece warping.

Beyond that, some people use cardboard struts (similar to the default bracing, but easier to remove after the fibreglass has set) during the fibreglass stage, especially with larger pieces, to be completely certain that no warping will occur, but generally the bracing is only used during the initial resin application, and serves no purpose during assembly.

What thickness of card did you use? It shouldn't be too deformed at this stage. You can try installing the braces and seeing if this rectifies the problem, but if you find it's still warping too easily or not holding its shape well, you may be better off starting from scratch with thicker card.
 
Since cardstock is relatively flexible, the bracing basically adds more rigidity to the piece and makes sure certain distances are correct (such as the width of a helmet at certain points). It should be installed while it is still cardstock, then, once a couple of layers of resin (or whatever initial hardening technique you are using) has been applied and the piece is more rigid and better able to hold its shape, they can be removed and fibreglass (or an alternative secondary hardening technique) can be applied safely without the piece warping.

Thanks for answering the question! Installing the bracing during the card stock stage was my intention, but rather, what I was asking was whether to install the bracing as I assemble the individual pieces, or to install them while the entire helmet is already assembled.

It seems like i could install the bracing once the entire piece is assembled, so I'll try that out. Thanks!
 
Make sure you are using thick enough cardstock.

If it's warping before you've even added a layer of resin then you've gone wrong somewhere. Don't make the folds by hand, score the lines with a blade or go over the lines a few times with a pen to get perfectly straight folds. What glue are you using?

Depending on how badly warped it is, it might be possible to save with filler. As for bracing/support struts, you can quite easily make some yourself, they don't need to be part of the pep file, just cut some strips of cardstock and fold them longways, and adjust the size until it fits the piece.

I am already scoring my folds quite nicely (and getting better at it!), so that doesn't seem to be the problem.

Super glue and hot glue? I am using Loctite super glue for the small pieces, and hot glue for the larger ones. Loctite is good when it works properly, but often times, I find myself waiting a longer time for the parts to stick (and sometimes they don't, and sometimes, they stick to my fingers or the tweezers more than the two pieces of cardstock!). I am already learning quite a lot; Loctite tended to slip the pieces around and caused it to set incorrectly. Additionally, the hot glue tended to be too bulky for some pieces, and distended some parts. That's where my warping problem was.

That's why I've decided to use flying_squirl's model; his bracing comes with the model, and it is measured to size quite accurately. So, I would at least want to know the best way to glue these pieces together - so they go where they're supposed to go.

By the way, I am using 110lb card stock.
 
x30ffx

I don't like using hotglue to do the initial gluing, I find it hard to work with and prefer just to use a craft glue. Its easier to work with and gives you a bit more time to align pieces but as similar to what you say about loctite, the joins aren't too strong and can let go especially on smaller pieces. I tent to use the hotglue as a secondary first gluing a part of the pepwork together with craft glue and the going over the back of each join with a thin layer of hot glue for strength. For hard to reach places just squirt a bit of hot glue on a popsicle stick and then rub it on the joins.

I didn't experience any of the deforming while doing the pepwork itself though so I too wonder if you're using thick enough cardstock. I did have issue during resin stage but am getting that under control now..
 
x30ffx

I don't like using hotglue to do the initial gluing, I find it hard to work with and prefer just to use a craft glue. Its easier to work with and gives you a bit more time to align pieces but as similar to what you say about loctite, the joins aren't too strong and can let go especially on smaller pieces. I tent to use the hotglue as a secondary first gluing a part of the pepwork together with craft glue and the going over the back of each join with a thin layer of hot glue for strength. For hard to reach places just squirt a bit of hot glue on a popsicle stick and then rub it on the joins.

I didn't experience any of the deforming while doing the pepwork itself though so I too wonder if you're using thick enough cardstock. I did have issue during resin stage but am getting that under control now..

Sounds good, I'll try that out!
 
It really is down to preference, back in my pep days I would use Hot-Glue and only Hot-Glue. You eventually learn how to keep the hot glue tidy and you can use the nozzle of the glue gun to re-melt glue so if you mess up it can be corrected. You also need to learn the right amounts, too much hot glue and it will either seep out onto the exterior of the piece or it will dry too thick leaving unwanted bulges and gaps between flaps. You especially need to be careful with the tiny tabs, they literally need the tiniest amount of hot glue.

Use what you feel most comfortable with. I think the issue with water-based glues is that they are absorbed by the cardstock, which can result in warping. Hot glue just sits on top of the card and bonds to it, not to mention it dries very fast and fairly hard. The hot glue alone provides good stability to a piece.
 
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