I was rather disappointed when I opened my new Estes #1951 Executioner kit, it did not have laser cut fin slots in the body tube. A cutting guide was in its place. As well as a shorter motor tube.

This is apparently the case with the Super Big Bertha, as well. I have done a number of hand cut slots, and one thing I find helpful is to use a small piece of angle aluminum as a cutting guide. I bought some that is 1/2" on each side. I cut a piece about 12" long from the longer piece I bought, and use it for a slot guide, as well as for marking fin lines on smaller tubes. I also have some that is 1" wide for larger models.

For slotting, I tape the angle aluminum in place, and make my cut. I then move it to the other side of the slot, and make that cut. The very short ends at top and bottom of the slot are cut freehand.

A new X-acto blade, drawn along the cut line 10+ times, will usually cut all the way through. I go slowly, and do not try to quickly cut all the way through.

Maybe with new ownership, Estes will choose to put more money towards things like pre-slotted tubes on more models. After tracing fin templates onto balsa as a kid, I guess I got programmed to do a lot of this kind of work, and actually enjoy doing a little hand-crafting on a build.

__________________
Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp

Thanks for the tips Lee, I do keep aluminum angle in my tool assortment. I'm kit bashing this for an Optima clone, and was going to cut the fins for through the wall, the pre slotted tube I was expecting was going to make the build a little quicker, as being a long haul trucker, I'm not afforded a lot of spare time.

I remember when we used to cut out the fins ourselves in some of the kits!

Still do. Some of the TLP, Fliskits, and Dr. Zooch models, among others, use fin templates instead of laser cut jobs.

** Cough, wheeze**


Yep, these young whippersnappers don't know how easy they have it nowadays: Pre-cut slots, laser cut fins, Kevlar, CA, 3D printed parts. We had none of those back in the day. And I remember walking 12 miles to school and back every day. By the time I got there had to turn around and go back home. Those were the days...… yep, yep, yep, yep, yep.....

*************** Snore ****************

Being a “senior” builder, I’m trying to step up my game. I’m employing some 3-D fabrications in my builds. My equipment uses a subtractive algorithm to remove material to obtain a finished part. Alas, symmetrical parts only.

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__________________
Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp

Upscale Saros? That should be fun.

Regarding the OPs question, I can definitely sympathize with regard to limited build time, but cutting fin slots is really quick, using the previously described technique of aluminum angle and a sharp blade.

I confess I don't fully grasp how Estes decides on which models to pre-slot the tubes, or for that matter when to use through-the-wall mounting in the first place.

The only thing I might add to the aforementioned technique is a coupler on the inside of the tube while making the cuts for the slot. Stiffens the tube and prevents paper tearing on the inside. But then the coupler might not be usable after that. So I'll say it's optional.

Highly recommended. I keep a sacrificial coupler around for support of all tube-cutting.

Yes, it is for an upscale Saros. Kind of a long term project. I need to turn the transition, and then there is that whole fin unit with nozzle. That Saros cone is from my 1976 Saros, my oldest rocket. I took it to NSL and Vern and Gleda Estes signed it. It likely won’t be flown again ...

And regarding comments from you and BARGeezer, the coupler really helps! I failed to mention that I use one on thin wall tubing. If it gets a little beat up, I’ll use it the next time I need to permanently join a couple tubes. I figure any cuts in it will just absorb the glue and it will be tough enough. Yep, I’m cheap.

__________________
Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp