Can spent 18mm engine be used as emergency coupler?

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AcadiaRockets

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Googling did not produce an answer. I am building a modified Comet Chaser and need a coupler. Not having one in my stuff it occurred to me I could take a spent engine to the chop saw and produce some couplers. Other than recognizing the inside diameter is not as generous as an actual coupler and its probably heavier - has anyone done this before?
Thanks,
M
 

mjennings

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I've used cut engine casings as engine blocks. You could use one as a coupler. It will be a good bit heavier as you say. A piece of body tube can be split down the long axis and formed into a coupler too.
 

Grant_Edwards

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Googling did not produce an answer. I am building a modified Comet Chaser and need a coupler. Not having one in my stuff it occurred to me I could take a spent engine to the chop saw and produce some couplers. Other than recognizing the inside diameter is not as generous as an actual coupler and its probably heavier.
If you want to spend the time, you can remove as many layers of paper from the inside as you want. The easiest way is to use a small saw blade or file to cut a notch on the inside to the desired thickness and then peel out paper until the notch is gone.
 

Back_at_it

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Yes. In an absolute pinch it can be used. It's heavy as you stated but it will work.

Just be sure to clean out the inside of any Residue.
 

Bill S

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Or if you have any extra plastic nosecones lying around, you could cut off the shoulder (the part that goes into the body tube), cut the end so its open, and use that as a plastic coupler. Probably heavier than a proper coupler, but may be lighter than a cut off motor tube piece, and certainly easier to work with. :)
 

BigMacDaddy

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Do you save those yellow engine spacer tubes that they give you with some kits? I would think that would work also although not as thick as a regular coupler...
 

sjh1

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Do you save those yellow engine spacer tubes that they give you with some kits? I would think that would work also although not as thick as a regular coupler...
I like the idea, but some of the ones I have fit rather loosely. I guess a little tape could fix that.
 

BigMacDaddy

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I like the idea, but some of the ones I have fit rather loosely. I guess a little tape could fix that.
Or craft paper and glue -- basically making your own coupler at that point but could be easier than starting from scratch...
 

wmay78

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Do you save those yellow engine spacer tubes that they give you with some kits? I would think that would work also although not as thick as a regular coupler...
I use these often as couplers on bt-20 tubes. I've saved them all from old kits
 

Homer_S

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Or craft paper and glue -- basically making your own coupler at that point but could be easier than starting from scratch...
I've done this to a loose coupler, essentially adding a layer of tube to it with a paper grocery bag and a thin layer of wood glue, staggered from the existing seam. Let it dry and trim the ends.

Homer
 

BABAR

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Motor casing will definitely work. I tend to just cut two lengths of whatever diameter body tube I am using (in your case BT-20), cut each lengthwise, roll piece 1 up and slide it 1/2 way into your first tube, roll piece 2 inside piece 1. Use white glue. Works great.
 
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