Can a 4" body tube be used for a 4" motor tube?

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Fuddrucker

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That's the question. I am in the middle of a scratch build and thought I had a 4" motor tube but when I went to find it I don't have one. I do have a glassed 4" body tube and the 98mm case fits in it perfectly so I was curious if anyone here has ever used a body tube as a motor tube?

...Fudd
 

rms

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That's the question. I am in the middle of a scratch build and thought I had a 4" motor tube but when I went to find it I don't have one. I do have a glassed 4" body tube and the 98mm case fits in it perfectly so I was curious if anyone here has ever used a body tube as a motor tube?

...Fudd
A 4 inch motor tube is a piece of 4 inch body tube. Are you of the believe that a motor tube is different?
Greg
 

Fuddrucker

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I thought they were in some cases. Mainly with a 3" tube. A 54mm body tube and motor tube looks the same to me but a 3" motor tube seems thicker than a 3" body tube so I thought a 4" tube might have just been a thicker walled tube for some reason.

...Fudd
 

REK

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To answer your question, Yes you can.

Motor mount tubes and body tubes are the same. Some motor mounts are beefed up for a few reasons, such as more strength. Some motor mount tubes are also only cut to a certain length.

Hope this helps


Sent from my iPhone using Tapatalk
 

Handeman

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If you have a couple or three CRs with the right size hole, you don't need a motor tube. Of course you can't glue fins to something that isn't there, but there are other ways of doing fins without a motor tube.
 

MikeyDSlagle

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Don't know about 4", but Madcow specifically says their 54mm body tube IS NOT the same as their 54mm motor mount, or vice versa. Maybe simply because of length? Never had my hands on a Madcow 54mm anything so I don't know.
 

Woody's Workshop

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The density of the fiberglass when casting a Engine Tube may be more than that of a body tube.
Because both are fiberglass, does not mean they are of the same density.
Also, a higher heat range resin may be used on Engine Tubes than on air frames.

I once questioned a friend at Estes if using a body tube for an engine tube was acceptable.
His response was that the body tubes are of better quality than the blue tubes used in engine tubes.
But, that is LP and has nothing to do with the OP question.

I would look into what air frame you have and find out the specifics (if possible) of what it is made of.
 

qquake2k

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When it comes to 75mm motors, they will fit in LOC 3.1" tubes, but not BMS T300 tubes. ID of the LOC is 3", but only 2.93" for the BMS. LOC does list a 98mm motor tube that is more expensive than their 3.9" airframe. So maybe it is thicker and/or stronger. But I would think if yours is glassed, it should be more than strong enough.

https://www.locprecision.com/produc...ribute_motor-mount-tube=98mm+Motor+Mount+Tube
 

MClark

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There are also real 4" motors, Kosdon, that will not fit in a 98mm tube.
With "3 inch" there are 75mm 76mm and some EX cases really are 3".


M
 

Woody's Workshop

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Metric...Imperial
I wish one or the other didn't exist.
When I was an auto body tech, the big 3 used Metric on cars and van, Imperial on trucks.
And many of the foreign vehicles was 1/2 and 1/2.
Talk about a RPITA!
Doubles the cost of tools, and headaches.
 
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