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So, I've got a FW Hydra emplacement (link) and the whole base of it is cast as a single large part. So naturally it is bent, a slight but noticeable curve so that the radar dish end of it is about a quarter to half an inch off the ground when the other end is lying flat on the table. How do I fix this? It's too large to dip in boiling water with any of the pots I have, and when I tried using a large flat pan it and pouring the water over it the water cooled off too quickly to get it bent significantly. Are there any alternatives that people have had any luck with? It's a really frustrating problem because the model is long OOP and there's no way to just get a replacement for it.


Note that this is NOT about smaller thin parts that you can just dip in boiling water, I've had plenty of those to fix and had no problems with them. This is about something where the basic method does NOT work.

A lighter can work. But it might be too thick a piece of resin.

Try heating it with a hair dryer and then working it back straight

I just tried the hair dryer and that didn't work. It was fine for the thinner test bit of the current resin, but this is a large thick piece of the old hard and brittle stuff and the hair dryer didn't even soften it a bit.

Have you got a photo of this part so we can see just how thick it is?

I've never tried this, but I wonder if you could bake in on a baking pan. Maybe set the oven on something low, like 100 degrees. Maybe even lower. Just let the heat work nice and slow. I would be concerned about the model sticking to the pan.


Automatically Appended Next Post:

Eldercaveman wrote:
Have you got a photo of this part so we can see just how thick it is?

He linked it in the OP.

The thing with the heating trick, hair dryer, water, wahtever you use, is you need to heat the resin to the core. It works quickly for thin peices because the core heats quickly, but for a peice like that, it's going to need to be warmed for a lot longer period of time. Keep it soaking in warm water for a lot longer, then give it a gentle attempt.

mount it on a piece of plasticard. had to do this with my chaos temple. get plasticard, add green stuff under dish to stabilise it, superglue other end. let it dry, fill in edge near radar with greenstuff. cut around emplacement to preserve general shape.

Microwave dry rice, I'm not sure whether you should put the resin in there or not. It seems like I've heard you can do that over stove top. Personally I've always been able to fix my resin under the hottest the tap water would go. If it is still to much I would suggest boiling it. Use a vegetable steamer to keep it off the actual pot (so it doesn't melt). But I think it floats depending on the size.

I'm terrified of using any heating method.. too many botched tries... LOL

I'll second the hair dryer. Don't hold it in one place, keep it moving, you need to heat the whole piece quite evenly.

With some pieces, it's worth making a jig to support any arches in the part.

Update: I've had some luck submerging it in boiling water for a few minutes and then bending it over the edge of the table. Using enough force to completely destroy anything made out of the current resin has succeeded in slowly bending it some of the way back into shape, so maybe with enough persistence that will get the job done.

I'm still interested in answers though, since this isn't even close to precise and I'm going to be lucky if I don't break anything.

 Orinoco wrote:
mount it on a piece of plasticard. had to do this with my chaos temple. get plasticard, add green stuff under dish to stabilise it, superglue other end. let it dry, fill in edge near radar with greenstuff. cut around emplacement to preserve general shape.

Sadly not an option. This was what I thought of first but the actual structure of the fortification is bent too, with the square radar dish end of it being noticeably bent upward from the Hydra mount. Filling it in would make it sit level, but it wouldn't look right otherwise.

winterdyne wrote:
I'll second the hair dryer. Don't hold it in one place, keep it moving, you need to heat the whole piece quite evenly.

This is what I tried doing, it worked fine with my test part but all it did to the real one was make it a bit warmer. Either the old resin just needs hotter temperatures, or my hair dryer is inadequate.

It takes quite a long time. Resin is not particularly thermally conductive - to warm the middle of the part takes ages, and certain mixes will not soften quickly!

However you don't need the part to be very warm - do not expect the piece to go flimsy or 'soft'; it may not appear to, but resin is not a fixed structure solid - . Any movement of the part can be very slow. It may be worth putting it on a flat board, warming it for 10 minutes, then leaving it for gravity to do its thing.

I've had to do this before too.

My only solution was my heat gun. Now before anyone flies off the handle about the suggestion, I have a variable temperature and air flow heat-gun. It basically allows me to use it as a more powerful hairdryer. Moving in circles over the warped area (damage occurs with too much heat in one place for too long.) will prevent any damage.

Heat from the flat bottom, this way if any damage does occur, it's to the part that doesn't matter as much as it's details. Once the resin becomes warm it will be maleable enough for you to flatten. Reheat the resin as many times as necessary.

You could also use a electric griddle (must be flat) - but this is more reliant on the temperature settings of the griddle itself. You would have to be able to hold your hand down on the griddle, as a rough temperature gauge.

Try putting it in a bowl of very hot water, if it works then quickly put in a bowl of very cold water and that should seal it.

Quenching (rapidly cooling) doesn't really work well on thick resin pieces; remember; resin does not conduct heat well.

You are likely to make cracks in the surface if you do this. Fair warning has been given.

The thicker the piece, the slower and more gently you should warm it to heat it evenly.

boiling hot water may be your only option if it's really bent up.

I've used boiling water to great success with forgeworld parts. When I built my storm eagle the fuselage sides looked like bananas. standard substandard forgeworld casting and this was a pre-order. After submerging the sides in boiling water they went as limp as a wet noodle and as I removed them they were straight under their own weight. I put them in cold water. really cold water. cold water + ice + salt = really really cold water. I would try a similar technique here.

I can't think of anything that will make it more malleable. The hair dryer will take ages if it works at all. Once the inside gets warm the outside will already be badly melted.

How about a heavy stack of well placed rule books ect, just let it set for a few days and see if it will flaten out.

Is there anyway you can just add green stuff or foam insulation to fill the gap from the warping?

I used hot water in the bath for my thunderhawk hull as that was pretty badly warped. Seemed to do the trick but needed to soak for a fair amount of time

 Vithmorax wrote:
How about a heavy stack of well placed rule books ect, just let it set for a few days and see if it will flaten out.

Without heating the resin, this will result in one of two outcomes - nothing happens, or the peice snaps. The part he's talking about it a very brittle type of resin Forgeworld use for large single peices. My Heirophant body is made from the same stuff.

The only time I've had to do this to a large flat resin part I put it on some tin foil on a baking tray in the bottom of the oven, put another baking tray on top and put a brick on it. I set the oven to 110 degrees and kept an eye on it for an hour or two so until it bent to shape, then turned the oven off and left it to cool.

It worked nicely, although I'm not sure if it might squash the walls of the emplacement if you try it with that particular piece, you'd need to keep a close eye on it.

Get them to send you a replacement. Repeat until you receive a correct piece.

 JohnnyHell wrote:
Get them to send you a replacement. Repeat until you receive a correct piece.

 JohnnyHell wrote:
Get them to send you a replacement. Repeat until you receive a correct piece.

OP:

 Peregrine wrote:
It's a really frustrating problem because the model is long OOP and there's no way to just get a replacement for it.

Meh. So I should read better! Sue me. ;-)

You should also learn the ropes of resin models.

Warping can occur from a variety of reasons, many of which are unavoidable if you are holding stocks of models.

Bends (especially in large parts) cannot really be considered a flaw in the same way as bubbles or voids. This said, 'twists' and some severe bends caused by pre-cure pulling can be problems to fix. Simply demanding replacement on replacement if the cast is reasonable will cost you more time and effort than performing a simple fix.

Very common problem - and a warped bit (no matter how large) wouldn't automatically be a defect. Believe it or not - sometimes it can happen just because of the way it is stored in a box...especially if it has been sitting for long periods of time with other stuff pushing on it.

The way I generally handle big stuff is a toaster oven. I have one with a temperature range that starts down at 125 which is cool enough to deal with resins and I can crank it up to melt some of my low melt metals as well (different process for that need).

Anyway, I have some plate steel which was cut to give me something flat to set the resin on (as opposed to flimsy cookie sheets which can be just as badly warped as the resin). In addition I have some small steel blocks of varying thicknesses and sizes just in case there are knockouts and other things which I need to go ahead and support to get it flat.

Set the part to be heated on the plate - support as needed. Turn the temperature up to around 125-150 and go do something like mow the lawn. The exact time depends on the thickness of the part and the particular resin in question. Thickness of the parts end up creating an almost exponential relationship to the heating. If something is 1/16" and it takes 5 minutes then something that is 1/8" thick might take 25 minutes (not an exact formula - but you see the train of thought).

Quite often - the part will just settle down onto the steel plate, though more often than not you will need to fudge things by hand. Get it all lined up and straight then leave to cool on its own.