Creating Aluminum Plates for your rocket heinie...

[mrwalsh85]

Hi Everyone,

I just wanted to share what I created for my L3 project and show that it can be done with the simplest of tools.

I created an aluminum plate that bolted to the aft centering ring of my WAC Corporal and my Aeropack 75mm flanged retainer bolted right to this plate with no issues.

I will create a how-to using paper as I've already created this, and don't see myself doing a 7.5" bird anytime soon... However if anyone has any questions or needs help making one - let me know.

This project only cost me $3 as I found the material in a scrap pile at the metal supplier near me. I already had all the tools as I've acquired a number of tools. Again, don't freak out. Yes, some tools are required. No, you don't need a mill. However, having a lathe would be a tremendous asset. If not, a belt sander and a drill press could work. I used a lathe to machine the OD and the ID - no, I didn't use a micrometer or 12" calipers as we're not trying to get down to thousandths on the OD/ID. I will try to post some alternative ideas that could be carried out if one does not have a lathe.

Here are some photos.




I will do a step by step on how to do this - hopefully in the next day or two. I just wanted to get this thread up before I forget. If anyone has interest and wants to see how I did this, please don't hesitate to post and remind me

Basic Tools needed:

0-6" Dial Caliper - A digital caliper would do just as well (or a vernier if you know how to use one). You can get them from Harbor Freight (just looked - they are running a sale - $19.99 for digital, $18.29 for dial. I'm partial to the dial calipers as they are mechanical and don't "die" unless you mess 'em up).
Protractor - metal tipped - I purchased this one and used it for this project. Ignore the pencil part - the sharp metal tips are what you need (to scribe the aluminum).
Spring punch - $2.99
Drill press - Whatever size drill bits you need will depend on what you need. I'll list what I used and for what reason.
Taps - I used taps to tap the flanged bolt circle so I didn't have to put nuts on the back side.
Lathe - EASY and quick! I was able to machine the OD and ID in about 15 mins, including setup.

Having layout fluid would be a huge help (dykem, or you can get a FAT sharpie and just cover the area you're working with ). This helps you find your scribed lines easily and quickly. And if you mess up, you can cover it back up.

 

[dixontj93060]

Pretty!

 

[cwbullet]

subcribed - very nice.

 

[mrwalsh85]

So first things first. You'll need to decide on your bolt circle/patterns.

I used dial calipers to measure out the flange bolt circle on the retainer. The dimensions were double checked against Aeropack customer service. For the bolt circle that is used to attach the plate to the rear centering ring, I simply calculated OD - (1/2ID). UpscaleCNC did the custom machining for me and the work came out nicely.



I drilled out the bolt circle with a #6-32 CLEAR drill bit (so the threads will actually NOT grab the wood surface). I used a 5/16" drill bit for 1/4-20 tee nuts on the outer bolt circle.



When I do my demonstration of the layout, I will use a piece of poster paper and a paper protractor since I've already done the work. I would do another aluminum plate, but am not sure what rocket I'll be building next (let alone what motor mount size).

Hope to draw it up tonight or tomorrow

Mike

 

[mrwalsh85]

Oh yeah, I forgot to post the KEY to the whole process.

I was thinking about what I had available to me and finally decided that circular extrapolation would be the best choice.

Seeing as I have access to it, I used AutoCAD and confirmed the dimensions with Nat at UpscaleCNC as he had already machined the wood components.



I'm fairly confident that basic trigonometry can be used to find the coordinates. Be sure to double check your coordinates after you've calculated them. Protractor and pencil would be a valuable asset here.