AT RMS vs RMS Plus?

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4regt4

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I see some references to "RMS Plus" motors. Are these different than regular RMS motors? In particular, 24/40, 29/40-120, and 29/180. For example, Sirius Rocketry's listings for 29/180 are described as RMS Plus.

To confuse things even more, a search of this site revealed a discussion from several years ago of drilling delays for the 24/40 motors, saying that the delay grains for RMS and RMS plus are different.

Confused.

Hans.
 
18/20, 24/40 and 29/40-120 are not RMS (technically they are Reloadable Motor Systems) they are Hobbyline reloads.

29/180, 360, as well as several shorter length cases 40, 60, 100, 120, 240 iirc are all RMS or Highpower style reloads, RMS Plus is just a variant of the RMS line.

All AT and CTI reloadable motors have adjustable delays (well not 75mm or 98mm as they do not have delays) and a drill tool is used to drill/shorten the delay, and there are different drill tools for Reloads and Disposable motors.
 
If memory serves me right RMS Plus became about just by moving the delay o- ring from in the front of the delay grain resting against the top of the delay well to around the forward end of the delay grain resting against the sides and front of the delay well.
OK in other words the delay o-ring now slides on to the delay grain whereas before the o-ring sat on top of the delay grain.
In other words the way the HPR are assembled now.
 
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18/20, 24/40 and 29/40-120 are not RMS (technically they are Reloadable Motor Systems) they are Hobbyline reloads.

29/180, 360, as well as several shorter length cases 40, 60, 100, 120, 240 iirc are all RMS or Highpower style reloads, RMS Plus is just a variant of the RMS line.

All AT and CTI reloadable motors have adjustable delays (well not 75mm or 98mm as they do not have delays) and a drill tool is used to drill/shorten the delay, and there are different drill tools for Reloads and Disposable motors.
Don't quite think so....

Looking at Aerotech's webpage, the Hobbyline motors are shown specifically as "RMS Mid Power". So they ARE RMS also.

And I still haven't figured out what RMS Plus is. What is different?

Hans.
 
If memory serves me right RMS Plus became about just by moving the delay o- ring from in the front of the delay grain resting against the top of the delay well to around the forward end of the delay grain resting against the sides and front of the delay well.
OK in other words the delay o-ring now slides on to the delay grain whereas before the o-ring sat on top of the delay grain.
I have some recently made reloads as well as some 10 years old, all have the delay o-ring placed above the delay grain. Somewhere here abouts, I have heard others mention wrapping the o-ring around the delay grain, but above the delay insulator sleeve. But none of mine are like that. So do I have the "plus" or not?

And what is the 29/180 RMS Plus hardware that Sirius is selling? Is it different than the 29/180 hardware that other vendors have, not labeled "Plus"?

Still confused.

Hans.
 
Don't quite think so....

Looking at Aerotech's webpage, the Hobbyline motors are shown specifically as "RMS Mid Power". So they ARE RMS also.

And I still haven't figured out what RMS Plus is. What is different?

Hans.
At this point its marketing, the only one to watch out for is if you see RMS-Ez..then run.
Follow the directions that came with the product, the casings have not changed.
 
At this point its marketing, the only one to watch out for is if you see RMS-Ez..then run.
Follow the directions that came with the product, the casings have not changed.
Ah, OK. Thanks. Somewhere in the back of my mind I remember mention of the RMS-Ez, and I may have had this crossed up with the "Plus", whatever that is.

Hans.
 
Ah, OK. Thanks. Somewhere in the back of my mind I remember mention of the RMS-Ez, and I may have had this crossed up with the "Plus", whatever that is.

Hans.
RMS EZ was an attempt to be almost as simple as CTI with no delay element to assemble, they had lots of failures before AT figured it out, by then it was too late.
 
I have some recently made reloads as well as some 10 years old, all have the delay o-ring placed above the delay grain. Somewhere here abouts, I have heard others mention wrapping the o-ring around the delay grain, but above the delay insulator sleeve. But none of mine are like that. So do I have the "plus" or not?

And what is the 29/180 RMS Plus hardware that Sirius is selling? Is it different than the 29/180 hardware that other vendors have, not labeled "Plus"?

Still confused.

Hans.
The hobbyline motors are RMS the HPR motors are RMS Plus. You have the RMS Plus if they are HPR. The Plus have been here for a long time already. No difference in the 29/180 hardware.
 
And what is the 29/180 RMS Plus hardware that Sirius is selling? Is it different than the 29/180 hardware that other vendors have, not labeled "Plus"?

My AT hardware is from the 90's and all of my reloads are new. Looking at some of my empty motor tubes, I've been flying RMS plus reloads and I don't think I even knew it.

It looks like RMS Plus was the new name given to reloads when they switched to full-delay grains only, leaving you to use the delay tool if you want a shorter delay.

RMS came with delay choices, no drilling unless your wanted an in-between value.

Same hardware, except the need for the delay drilling tool.
 
My AT hardware is from the 90's and all of my reloads are new. Looking at some of my empty motor tubes, I've been flying RMS plus reloads and I don't think I even knew it.

It looks like RMS Plus was the new name given to reloads when they switched to full-delay grains only, leaving you to use the delay tool if you want a shorter delay.

RMS came with delay choices, no drilling unless your wanted an in-between value.

Same hardware, except the need for the delay drilling tool.
The RMS Plus used to come in assorted delays.
 
If memory serves me right RMS Plus became about just by moving the delay o- ring from in the front of the delay grain resting against the top of the delay well to around the forward end of the delay grain resting against the sides and front of the delay well.
OK in other words the delay o-ring now slides on to the delay grain whereas before the o-ring sat on top of the delay grain.
In other words the way the HPR are assembled now.
That is correct. This also required a change in the delay casting tube, from paper to plastic.
 
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