Aerotech 18/20 RMS & Estes 18/24mm adapter

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Well-Known Member
TRF Supporter
Jun 18, 2014
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Windsor, Ontario
I picked up a set of the 18/24mm adapters from Estes in the hopes of using it with my Aerotech 18/20 RMS. Unfortunately it doesn't work. The aft end of the Aerotech RMS does not fit in the Estes adapter.

What's an easy way to use my 18/20RMS Aerotech in a 24mm mount? I'm thinking of friction fitting it in a used 24MM casing.


cheers - mark
For a 18mm reload, I would use the old Estes EM-2050. It consisted of a BT-20J (2.75" long), two AR-2050 rings, one AR-2050S split adapter ring, and an engine hook (EH-2). An 18mm thrust ring is optional. If you are using the current Estes hook, you need to trim a little from the front of the hook to allow the forward closure the clear. Apogee, FlisKits, and eRockets (Semroc) still sell the older style of engine hooks (without the hang up on the launch finger tabs). The new plastic Estes 18mm/24mm adapters are sized for the paper cased and 18mm (D10 and D21) single use motors.
I have absolutely gotten my money's worth out of the Rocketarium 18/24 Adapter. It works with Rocketarium, Aeropack, and Estes 24mm retainers without modification. It pays for itself fairly quickly considering a D13 reload is about a dollar less per load than a D9 and will give a really nice boost to lighter BT-60 rockets!

I highly recommend this option for convenience. I have also received outstanding service through

I currently have an adapter for 13mm in 18mm, and 24mm in 29mm that I made with just rings and tube. The motor is friction fit. I plan to assemble one for 18mm in 24mm as well, but I think adding a hook might be a good idea. I don't use the 18mm reload casing so the hook and ring are not a problem.

If you wish to build an adapter for the reload casing, I would suggest that you bend the upper end of the hook out and tuck it behind the upper centering ring. You will want to heat the hook when you bend it. Hooks are easily made using the stainless steel strip from an old windshield wiper..... The thrust ring is your choice, just make sure it is deep enough and the ID is large enough for the reload casing
Thanks everybody, some good ideas here. I'll dig through my parts box tonight and see if I have the parts to make up an adapter that I can use for this weekend at NYPower. The rocketarium adapter looks really nice, I'll probably pick one of those up in the future.

cheers - mark