Can someone measure the OD of a 38mm DMS motor for me?

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ChrisAttebery

Well-Known Member
Joined
Feb 15, 2014
Messages
2,454
Reaction score
90
I need to cut a set of adapter rings to put a 38mm AT DMS motor in my 54mm mount. Does anyone have a 38mm DMS motor and a set of calipers? Can you give me the OD of the motor measured at the label?



Thanks,


Chris
 
What is the spec for this metric case?

...answers in inches.

This is how you crash landers into Mars folks....
 
All of the official DMS case dimension data is available from Aerotech here:

https://www.aerotech-rocketry.com/resources.aspx?id=7

According to their documents, 38mm case outer diameter is officially spec'ed at 1.500", with the diameter of the rear closure slightly larger at 1.630". Both diameters +/- .005 inches

-Robert
 
Last edited:
That is 3 thousandths of an inch shy of 38mm. It is basically 38mm.

I was wondering about that too. Since the question specified a measurement at the label, I figured the OP needed more precision than what it said on the box.

What is the spec for this metric case?

...answers in inches.

This is how you crash landers into Mars folks....

<smile>

Looks like they stopped updating the Mars scorecard a while ago. I think the folks running the site were discouraged by the unlikely successes of the air-bag bounce landings of the rovers.

There's more than one way to crash a lander -- the ESA managed it without the direct assistance of Americans and our weird fetish for imperial weights and measures.

It is a little frustrating to work between unit systems. I tend to think in terms of SI, but I've gotten some comments and quizzical looks from LCOs when it's noticed that I've recorded the mass of the rocket in grams on the flight card. The acceleration due to gravity is near enough 10 m/s2 that the thrust-to-weight estimate is pretty effortless. The arithmetic of converting newtons to ounces or pounds is tedious and time consuming.
 
Back
Top