Sold Any Interest in 18 mm G12 motor cases?

I'm considering purchasing a lot of G12 tubing sized for 18 mm motors. .625" ID, .703 OD, both +-.005". If I order, it would be this week. Pricing would be $20 to $25 per 60" length, shipping extra (whatever Parcel Post charges). These are not for sale yet.

Wound to hold pressure as a motor or made for coupling and airframes? If wound to function as a motor casing I’ll take three.

What's the max pressure these can hold? Might be fun to experiment with as this would be lighter than aluminum.

I'd definitely be in, these are just right for my machbusting tubefin.

Would they be substantially different than uncut Mach 1 Rocketry coupler stock?

dhbarr said:

Would they be substantially different than uncut Mach 1 Rocketry coupler stock?

Click to expand...

I don't know what the coupler stock dimensions are as I can't find them on the Mach 1 Rocketry site. These would be for motor casings. RCS RMS internal parts would fit although I will roll casting tubes from paper tape.I don't have pressure ratings, would have to be tested.

I’ll take three then

Might be interesting for a core burning type motor (or finocyl), assuming you can figure out the closure retention part of it.

Rocketjunkie said:

I don't know what the coupler stock dimensions are as I can't find them on the Mach 1 Rocketry site. These would be for motor casings. RCS RMS internal parts would fit although I will roll casting tubes from paper tape.I don't have pressure ratings, would have to be tested.

Click to expand...

For sure, in any case I'd be down with 4 of them.

Rocketjunkie said:

I don't know what the coupler stock dimensions are as I can't find them on the Mach 1 Rocketry site. These would be for motor casings. RCS RMS internal parts would fit although I will roll casting tubes from paper tape.I don't have pressure ratings, would have to be tested.

Click to expand...

I'll take two then. Maybe try and make a sub min diameter rocket with fins bonded directly on.

Tubing ordered. Should be here in about 8 weeks. For shipping, I'll probably cut in half. It comes in 60" lengths. These are intended as single use motors, just bond the nozzle in and use an epoxy bulkhead for the forward end.

Rocketjunkie said:

Tubing ordered. Should be here in about 8 weeks. For shipping, I'll probably cut in half. It comes in 60" lengths. These are intended as single use motors, just bond the nozzle in and use an epoxy bulkhead for the forward end.

Click to expand...

Nice! I've been thinking about how I plan on doing my motors. I want to do a fin can, but I need to figure out exactly how to do that since I plan on using fiberglass. Maybe I'll ask Mike Fisher if he can make one.

I've made many sub minimum diameter rockets with SU motors. Make the motor 1/2" longer than you would normally. Slit a piece of motor casing tube and use it as a coupler. Epoxy it into the front of the motor when you make the motor. Use another piece of motor case tube as the upper body.
You will be surprised how well plywood survives mach 2 Even an Estes Gnome will survive 1000 mph on a D40-10 (once). The picture is a 13mm full D40. Fins are 1/32" plywood. The motor is reloadable and consists of 4 1" long grains with 5/32" cores and a 3/4" long delay grain of the same composition as the propellant. Maximum delay is 13 sec.

I've attached my design. I plan on making a 10G motor and turning (out of aluminum) the transition and nosecone. I may try and make the nosecone out of something lighter but I am not sure yet.
The 10G motor will be a ~G300 and should easily hit mach in less than 500 feet.

Rocketjunkie said:

I'm considering purchasing a lot of G12 tubing sized for 18 mm motors. .625" ID, .703 OD, both +-.005". If I order, it would be this week. Pricing would be $20 to $25 per 60" length, shipping extra (whatever Parcel Post charges). These are not for sale yet.

Click to expand...

Are those tubes made with 55° wind angle? This is one of my project motors... an E-82 Mach 1.5 capable in the Mach 1 rocketry Exiter kit.

I have about 6 feet of this size tube left, but will want more at some point. This tube came from IDSI.... https://idsiofga.com/

Update. I'm expecting shipment on 3-30.
Yes, these have a 55 deg wind angle.

The tubes are in! They are .705-.706" OD and the ID fits RCS 18 mm nozzles fine.
The large ones are 98 mm liners to fit Aerotech hardware.

beeblebrox said:

I have about 6 feet of this size tube left, but will want more at some point. This tube came from IDSI.... https://idsiofga.com/
View attachment 407840

Click to expand...

Cool motor I'll have to check IDSI, they're only about 1 hr by car from me. It would have saved me $150 in shipping on this order. I'm looking at a new propellant for these. Much slower, possibly a D grain. Starting with a zinc based grain though.

Can't wait to see some fly!

Rocketjunkie said:

The tubes are in! They are .705-.706" OD and the ID fits RCS 18 mm nozzles fine. View attachment 410876
The large ones are 98 mm liners to fit Aerotech hardware.

Click to expand...

Woo! How many can I buy? PM me an address to pay.

I'm not trying to make a profit, just trying to cover my actual expenses. Not charging for labor either.
Tube price $25 each for 5 ft piece. Max 10 tubes per order. Will ship in 4" x 4" x 60" box.
4-10 pieces I will absorb packing costs. Less than 4 pieces, add $4. All shipments will be in full 60" lengths.
I will charge actual shipping, Priority Mail. Ranges from $9.20 to $23.15 depending on distance for a 4 lb. box. No international shipping.

If you are interested, PM (conversation) me with the quantity you want and a shipping address, along with an email address.
I will respond by email with the final price and PayPal address. I have 100 lengths, willing to sell up to 60 lengths.

I should get the boxes in today (4-1) and will be able to get shipping weights tonight.

I've weighed the packing materials and tubes. 1-2 tubes ship as 2 lb., 3-5 3 lb., 6-7 4 lb., and 8-10 5 lb.
Again, actual shipping cost depends on distance. Include a shipping address in your PM.
I will get back to you with full cost.

Since I got the tubes in, I've made some motors. See the thread https://www.rocketryforum.com/threads/18-mm-motors.158722/