When I was a teenager, I had Der Red Max and flew it several times on B and C motors. It's last flight landed it at the top of a 60' maple tree and I never saw it again. I rebuilt the 1.6x upscale from Aerotech components. The nose cone is a standard Aerotech cone with the end cut off and a balsa plug inserted. It is powered by 24mm motors and flys great on D12 and E18 motors.
The small one is BT-50 based with an 18mm mount. I got the decals from JimZ and the cone from Balsa Machining Service. I just purchased a semi-custom ogive cone that was a little too long and rounded the tip. It has only flown on 1/2A motors.
Following is a chart of scale information for every size of tubing I know of. It can give you the information you might need if you're trying to build your own Red Max. The tricky part of building a Red Max is getting a nose cone of the proper profile with a rounded tip. The ogive nose cone needed is a little less than 5:1 ogive with about 10% of the tip removed and rounded over. The chart gives finished sizes.
| My Fleet | Description | BT Size (OD) | BT Length | NC Length | Scale |
| T-2+ (MicroMaxx) | 0.281 | 1.46 | 1.14 | 0.17 | |
| TT T-3 | 0.375 | 1.95 | 1.52 | 0.23 | |
| TT T-4 | 0.448 | 2.33 | 1.81 | 0.27 | |
| BT-5 | 0.544 | 2.82 | 2.20 | 0.33 | |
| BT-20 | 0.736 | 3.82 | 2.98 | 0.45 | |
| Rogue T-22 | 0.850 | 4.41 | 3.44 | 0.52 | |
| T-.908 (ST-8) | 0.908 | 4.71 | 3.67 | 0.55 | |
| * | BT-50 | 0.976 | 5.07 | 3.95 | 0.60 |
| 29mm motor tube | 1.210 | 6.28 | 4.90 | 0.74 | |
| BT-55 | 1.325 | 6.88 | 5.36 | 0.81 | |
| BT-56 | 1.300 | 6.75 | 5.26 | 0.79 | |
| BT-60 | 1.637 | 8.50 | 6.62 | 1.00 | |
| Rogue T-45 | 1.750 | 9.09 | 7.08 | 1.07 | |
| Aerotech 1.9 | 1.880 | 9.76 | 7.61 | 1.15 | |
| T-2.04 (ST-20) | 2.040 | 10.59 | 8.26 | 1.25 | |
| BT-70 | 2.217 | 11.51 | 8.97 | 1.35 | |
| 54mm motor tube | 2.260 | 11.74 | 9.15 | 1.38 | |
| * | BT-80 | 2.600 | 13.50 | 10.52 | 1.59 |
| 3" LOC/PML | 3.100 | 16.10 | 12.55 | 1.89 | |
| 4" LOC/PML | 4.000 | 20.77 | 16.19 | 2.44 | |
| T-4.476 | 4.546 | 23.61 | 18.40 | 2.78 | |
| 5.54" LOC | 5.540 | 28.77 | 22.42 | 3.38 | |
| 6.15" PML | 6.155 | 31.96 | 24.91 | 3.76 | |
| 7.67" PML | 7.672 | 39.84 | 31.05 | 4.69 | |
| 11.6" PML | 11.660 | 60.54 | 47.19 | 7.12 |
My Fleet indicates the ones I have built (*) or that are under construction (^)
Description is what the tube is commonly called
Tube OD is the outside diameter of the body tube, all scale data is based on the original Der Red Max being an Estes BT-60 which has a diameter of 1.637"
BT Len. is the length of the cut body tube
NC Len. is the approximate exposed length of the nose cone
Scale is the scale factor, how many times the original size the model will be