Undersized centering rings, again, Really Estes

[Rex R]

I had a set of rings that were undersized (outside diameter) by about 1/32" with my super neon xl kit. now I find that the rings for my recently purchased Big Bertha(date code 01/ 05/ 16) are also undersized(outside diameter) by about 1/32"! while I can and will deal with the same way I did before (gluing a strip of cardstock around the ring), what about an inexperienced builder who using them as is? will their motor mounts go flying up through the rocket? or will they get a nasty case of 'coke bottle' from trying to use enough glue? while I suppose that they might have shrunk inside a pair of sealed parts bags (thickness 0.0385") somehow I doubt that is the case. oh, and both sets of rings were laser cut.
Rex

 

[Trident]

Sounds like a quality control issue. Most Estes centering rings I've dealt with are snug, and often need a bit of sanding to slide into the body tube.

 

[Rex R]

the super neon xl kit was dated 28/10 so apparently they must have cut a Bunch of wrong size bt60 centering rings. one set of rings I'll consider a fluke, two sets is time to Squawk!
Rex

 

[Rex R]

rather than going through the hassle of shimming the ring (shimming the tube is NOT an option), I decided to replace the rings, a few minutes w/ a dremel/sanding drum removed the offending ring from the motor mount, a bit of filing got the new ring(from erockets) to fit over the engine hook. now I wait for the glue to dry (again).
Rex

 

[T-Rex]

Thanks for sharing! I don't buy very many Estes kits anymore, but it is something that I'll watch for in the future. I do want a Big Bertha, maybe I'll just build a clone since I would probably want to purchase new rings anyway....

 

[Rex R]

and so I checked the rings that came with the Estes Cuvilinear* (yet another bt60 bird), while I did not test the inside diameter (bt5 motor mount), the outside diameter has the same defect as the other reported rings, they are undersized by the same amount. why am I not surprised, guess I'll have to buy a number of rings for each bt60 bird(sigh).
*kit date code 09/ 13/ 12
Rex

 

[Rex R]

while I was at it I gave the rings for my bt60 Nike Smoke some close scrutiny...w/o taking them out of the parts bag and actually testing the fit, the ole mk1s suggests that they too are undersized.
Rex

 

[hcmbanjo]

while I was at it I gave the rings for my bt60 Nike Smoke some close scrutiny...w/o taking them out of the parts bag and actually testing the fit, the ole mk1s suggests that they too are undersized.Rex

I've had a few sloppy fit rings over the years, the previous Saturn V rings were small in the BT-101.
I've got two BT-60 based Estes Nike Smoke kits being built right now. The 20/60 centering rings are a perfect fit.
The embossed date on the decal says 01/08/16.

 

[Steve Shannon]

Is it possible Estes included centering rings intended to fit in a coupler?

 

[Rex R]

that could be I suppose...but they forgot the couplers. let me check and get back to you.
Rex
*edit*
they don't quite fit inside a semroc/erockets coupler (rings from curvilinear (5-60) and BBertha( 20-60)) so I suspect that they were not intended to do so.

 

[Rex R]

I suspect that they would even fit if one were to leave the nubs on(which might be a design choice, messy choice though).
Rex

 

[Woody's Workshop]

Rex, I would call Estes!
At least ask them to send a couple packages that contain card stock centering rings.
They may opt up and send you new kits.
Spare parts box will get bigger.