Alternative ways of de-warping resin?

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Shinnentai
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Alternative ways of de-warping resin?

Post by Shinnentai »

I've got the big Zentradi warship kit from Scale Solutions. I keep putting off working on it because one of the hull halves is slightly bowed outward. The degree of deflection is slight, but since the parts are very long it still makes for a big gap at the ends.

I've tried the hot water thing, but the resin SS uses is very stiff stuff, and even with the water boiling I wasn't able to move the part hardly at all. I also tried clamping the part straight, and leaving it in the attic for a few days (I live in SoCal, in summer attics and parked cars get frighteningly hot inside), with no success.

Is there another way to do this?
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DasPhule
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Post by DasPhule »

You could try a heating gun, but you have to be really careful if you do. You could burn the resin or yourself if you're not careful. Heat only the bent area, make sure you have on heat gloves, do minute rebends until it's right. The biggest problem I've had doing this is heating too big of an area and causing other areas to bend out of shape. Heating the resin until it discolors is also a bad thing, that means it's close to ignition and will turn black soon. You WILL NOT like the soot it makes!

You could also put it on a rack and stick it in the oven, but this makes the whole thing hot and hard to hold onto without messing up other areas.

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vaderman
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Post by vaderman »

If you have a heat lamp, that would heat the model evenly and allow you to gently move the bent section into place.

Good luck.

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Post by Scale Solutions »

The resin is not warped, the bend comes from a slight bend on the pattern. There is no point heating the resin as it softens around 250 degrees the same point it bursts into flames.

The instructions that come with the kit cover this, as I new the slight bend was there, if you start buy gluing the bow of the ship together with superglue and clamping it with the elastic bands supplied, then once fully set move backwards along the ship gluing and elastic banding, the two half's of the ship hold each other straight together. Hope this helps

Wayne Pugh
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Treadhead
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Post by Treadhead »

I'm not much of an expert in de-warping -- but maybe you could get a replacement part from Scale Solutions? Usually the GK folks are pretty accomodating when it comes to replacing stuff that didn't get cast properly...
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Shinnentai
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Post by Shinnentai »

I did read the instructions, but I don't trust that method. I've clamped it and rubber banding it many times now, and one thing I've been very impressed with is the extraordinary amount of tension required to bend the part even that much. It's kind of scary when the clamp starts to flex at the same rate as the part.

There aren't many glues I know of that I'd trust to hold that kind of tension over time. I'd much, much rather be able to just fix the bend. If I really can't fix it, then I'll probably abandon the kit, which I really don't want to have to do considering how much I paid for it.

Please don't take this as a slight. I'm very impressed with the properties of the resin you've formulated for your kits. I just find myself thinking that for model kit applications some of these properties go beyond the point of diminishing returns.

I don't expect any kit to be perfect, garage or otherwise, resin or otherwise. This resin's advantages only hold if the kit is perfect. If there are imperfections, then some of those advantages turn into strong disadvantages.

There needs to be enough play in the material for the modeler to make corrections or fixes if necessary. Flaws are not large or small in relation to how they effect the shape or fit, but rather in relation to how easy they are to fix: a huge shape inconsistency that can be fixed with a few simple shims is a very small problem compared to a much smaller inconsistency that needs grinding, puttying and reconstruction of erased detail to fix.

Since the kit is hollow along the long axis, all I have to do to prevent droop is epoxy a length of large diameter metal tube inside (something I was going to do anyway). The resin doesn't need to be that foolproof, and in practice all this kind of temperature resistance really means is that it's much, much more difficult for me the end user to fix this problem to my satisfaction.

A kit I have to spend an extra $8.00 and twenty minutes reinforcing internally and thereafter never have to worry about again is better than one I can't fix at all, or can't fix without resigning myself to feeling forever paranoid about it springing apart if it happens to get knocked.

Again, please do not take this as an insult, but rather in the spirit of constructive feedback.
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Post by Scale Solutions »

I have put about 10 of these together following my own instructions, using zap-a-gap, and never had a problem, in fact the first kit that was put together has now been assembled since march 2006 with no sign of it coming apart see attached pic's of it as of today. I might add I have been using the same resin and glue for about 9 years and have never had anything come apart without having to use violent force on it.

http://users.hunterlink.net.au/~ddwwp/pic/002.JPG
http://users.hunterlink.net.au/~ddwwp/pic/003.JPG
http://users.hunterlink.net.au/~ddwwp/pic/004.JPG
http://users.hunterlink.net.au/~ddwwp/pic/0010.JPG
http://users.hunterlink.net.au/~ddwwp/pic/006.JPG
http://users.hunterlink.net.au/~ddwwp/pic/007.JPG

Wayne Pugh
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Treadhead
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Post by Treadhead »

Zap a Gap is pretty strong stuff. It has very good 'pull' strength, which is what you need. It doesn't have good shear strength, but this won't be a problem as 'pull' strength is what you need here.

If you don't trust CA/Zap a Gap, you might try some JB Weld. This stuff is used for engine blocks. I used it to fasten my mailbox to the post when the weld seam failed. It's been holding up now for 3 years despite inclement weather and viloent mail carriers.
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