(Slow Build) L3 The AGM Special

[jfcote]

This thread is to document my L3 project: The AGM Special

Over the years, I accumulated parts for future projects, most of the time acquired at the Ottawa Rocketry Group annual AGM. I currently have the following new parts:

• 6” 5 to 1 gel coated fibreglass nose cone (Performance Rocketry)
• 6” x 36” G10 body tube (Performance Rocketry)
• 6” x 48” G10 body tube (Performance Rocketry)
• 6” G10 coupler (Performance Rocketry)
• RRC2+ altimeter (Missile Works)
• 2 x Screw switch (Missile Works)

Will see what I can build

I am planning to certify next June at LDRS in Potter NY. I would like to thanks my TAP: Debra Koloms and Harry (Mickey) Rowe.

I ordered ProLine 4500 epoxy and a 3" x 24" fiberglass motor mount at Composite Warehouse on October 27th.

This weekend I purchased some 9mm baltic birch plywood for the centring rings, e-bay bulk plates and fins.

After cleaning the garage, I washed the fibreglass parts I currently have. Then I cut the bulk plates for the E-bay and the nose cone. I will try to cut the centring rings, the fins and slot the body tube next weekend.

 

[pathtouch]

How well do those circle cutting tools work? I often just rough cut on a bandsaw and sand into a circle ish shape but would like more precision.

I’ve done it on a router table but for smaller diameters it doesn’t not seem like a safe idea.

 

[Rschub]

How well do those circle cutting tools work? I often just rough cut on a bandsaw and sand into a circle ish shape but would like more precision.

I’ve done it on a router table but for smaller diameters it doesn’t not seem like a safe idea.

The fact that these are marked "good" sort of implies that there are some marked "bad"

 

[troj]

How well do those circle cutting tools work? I often just rough cut on a bandsaw and sand into a circle ish shape but would like more precision.

I’ve done it on a router table but for smaller diameters it doesn’t not seem like a safe idea.

Fly cutters can work well, but require extreme caution and proper precautions when in use. OP was the work piece well secured, which is one very important aspect of using them.

My preference is a circle jig with a router, which I find to be a lot easier to get accurate circles with, as well as less concerning to use.

-Kevin

 

[jfcote]

How well do those circle cutting tools work? I often just rough cut on a bandsaw and sand into a circle ish shape but would like more precision.

I’ve done it on a router table but for smaller diameters it doesn’t not seem like a safe idea.

It works well. Once you have the proper adjustment, you can cut identical parts relatively fast.
You need to secure properly the part you drill. Never ever try to hand hold it.
You need to adjust your drill press to a low speed.
Do yourself a favour, purchase a quality one.

Cutting the centering rings will be more challenging. I think I will have to use finishing nails to hold the part when I will drill the central hole.

 

[jfcote]

The fact that these are marked "good" sort of implies that there are some marked "bad"

Yup, test parts used to fine tune the adjustment of the cutter.

 

[troj]

Cutting the entering rings will be more challenging. I think I will have to use finishing nails to hold the part when I will drill the central hole.

Finish nails or screws to a larger board that you can clamp. Either way would work well.

-Kevin

 

[jfcote]

Finish nails or screws to a larger board that you can clamp. Either way would work well.

-Kevin

Screws is the way to go. I had a hard time removing nails on a test part.

 

[jfcote]

Was a busy week.

I received the 75mm AeroPack and the CTI 75mm 4grains motor case. I also got a 15 degree router bit to bevel the fins

I completed the centring rings and cut the fins. I also built a jig to help me cut the coupler with a miter saw.

Next weekend I will bevel the fins on the router, cut the fin slots on the body tube with my Dremel and will trim the coupler to 14" and cut the a 2" switch band.

 

[jfcote]

Today we got some snow, it is a reminder that I have to hurry up, winter is coming.

 

[jfcote]

It was an other busy weekend.

• Beveled the fins with the router using the 15 degrees routing bit.
• Drilled holes in the bulk plates of the e-bay, nose cone and centring rings.
• Cut a 2" switch band from an old pice of fibreglass tube
• Cut the coupler to 14"
• Cut the fin slots with the Dremel
• Cut the all threads to size

I made good use of the Payload Bay template tools. It was a big time saver.

 

[jfcote]

I will not have much to report in the next few weeks, I am still waiting for my epoxy and fibreglass motor mount to be shipped. I will be working on my CAD skills for the 3D printed parts I am planing to make.

 

[Threemorewishes]

Looking good JF.

Hope I can make the launch to see your flight.

 

[jfcote]

Wow, I was able to purchase my motor: Aerotech 1297W and all the other missing parts for the project at a great discount during the Wildman Black Friday sale tonight. Thank you @WILDMANRS

 

[jfcote]

A little trip to the Ogdensburg's UPS store to pickup my order last weekend.

 

[jfcote]

Finally started to fiberglass parts. I am using 6oz cloth with West System 206 hardener. I got the bulk plates done yesterday with one layer of 6oz. It was mainly to facilitate cleanup of the BP residues.






This morning I started the fins. I laminated 2 layers of 6oz one side.

 

[jfcote]

In the last two weeks I completed the glassing of the fins on both sides. I still need to fix some low areas. I will mix a small batch of epoxy with some fillers.



I sanded the centring rings and started to dry fit the motor mount. Hopefully, I will be able to start to epoxy them this weekend.



Also, Saturday, I attended our club's AGM. I am proud that I resisted the temptation to purchase new rockets I even sold two.

 

[Flare]

Any chance the Ottawa club will get a new HP launch site? Would be great to have one in Ontario.

Good luck with the rest of the build. I might also go for my L3 at LDRS.

 

[Donnager]

If you get the chance, and you may already have one, but a rotary cutter will help keep from having frayed ends on your fiberglass cloth cuts.

It made my life much easier. It doesn't stop the loose ends on wovens, but it is better than scissors.

 

[jfcote]

Any chance the Ottawa club will get a new HP launch site? Would be great to have one in Ontario.

Good luck with the rest of the build. I might also go for my L3 at LDRS.

We may get one. It will start with model launches this year. I would suggest that you subscribe to the club’s mailing list for updates.

 

[jfcote]

If you get the chance, and you may already have one, but a rotary cutter will help keep from having frayed ends on your fiberglass cloth cuts.

It made my life much easier. It doesn't stop the loose ends on wovens, but it is better than scissors.

View attachment 630316

Yup, I have one and used it. I got the fiberglass at a local boat supply store. It was average quality and the staff was not gentle when they cut it. But it will do the job.

 

[Hobie1dog]

Keep the pictures coming.

 

[jfcote]

I secured the top centring ring with the Proline 4500. Anybody has tricks on how to measure small batches?

 

[Handeman]

If you haven't glued that eye bolt in place yet, you might want to angle it some. You need clearance between the Motor and the BT. If you plan to use a quick link, it might not fit between those two with the position you now have the eyebolt. Angling the eye bolt allows you to angle the quick link or cord when you install it. A little more room for everything.

 

[jfcote]

If you haven't glued that eye bolt in place yet, you might want to angle it some. You need clearance between the Motor and the BT. If you plan to use a quick link, it might not fit between those two with the position you now have the eyebolt. Angling the eye bolt allows you to angle the quick link or cord when you install it. A little more room for everything.

Good point, I will test it with the motor case and adjust the angle.

 

[thzero]

I secured the top centring ring with the Proline 4500. Anybody has tricks on how to measure small batches?

View attachment 631111

What is the allthreads purpose?

 

[jfcote]

Link the centring rings to spread the load

 

[jfcote]

I added filets to both sides of the two top centring rings. I mixed a 10 g of proline 4500 for each one. My plan is to glue in place the motor mount with the top two centring rings. It will give me access to the fins from the inside to do a good filet with the motor mount.



I have been sanding the fins. I still need to add some more epoxy with fillers to fill some low spots. But it is getting there.


I added some plywood to the bottom centring ring to add a threaded insert for the lower 1515 rail button.

 

[jfcote]

My initial plan for the e=bay was to 3D print it. But I sill have to work on my CAD skills ... I am using a 1/8" plywood for the bed. I used carpenter glue to attach the parts together.


I will use screw switches attached to the side,

 

[jfcote]

I finally glued the motor mount with the top two centring rings to the body tube. At first, I used some West System epoxy on the side of the tube glue the top centring ring. Then I used the Proline 4500 to do a nice filet on the bottom the middle centring ring.