Cutting Slots in Fiberglass

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John Kemker

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I managed to get a good deal on a 24" length of 54mm fiberglass (blue). I'm thinking of using it to make a fiberglass Nuke Pro Maxx. However, I need to figure out how to cut slots in the tubing. Suggestions?
 
For small tubes like 54mm, I prefer a jig and a plunge router with a straight bit. For a tube this small, you could even use a trim router.

I bought these plans from Macklin at some point:
https://www.macklinmissileworks.com...y-and-user-guides-rocket-tube-slotting-device
And have since built my own versions in different sizes.

Once I get up to tube sizes around 5" and up, I am with Tony - dremel, grinder with a cutting wheel, jigsaw, etc
 
Thanks, guys!

I have a Dremel (well, off-brand, but same idea), air die grinder, but no table saw (at this time). HOWEVER, it does provide me with an excuse to buy a trim router... [grin]
 
Look into CNC routers and make sure the trim router you buy is commonly used as an upgrade on the CNC system you may want. That way, you won't wind up with a really great trim router (e.g., Bosch Colt) and be thinking about buying another trim router to upgrade your shiny new CNC router.
 
Look into CNC routers and make sure the trim router you buy is commonly used as an upgrade on the CNC system you may want. That way, you won't wind up with a really great trim router (e.g., Bosch Colt) and be thinking about buying another trim router to upgrade your shiny new CNC router.
Hmmmm.....

Dunno, as I'm not likely to buy a CNC router. At least, I haven't been considering one, until now...
 
I’m pretty sure you need that CNC router so you can make crafty home decor for your wife!
Looking at CNC routers, it looks like I can spend about $150 for a Vevor or Sainsmart 3018 Pro, or I can build an even better one, starting with a router such as a Makita or DeWalt.

I'll probably do the second option.
 
My wife once asked me to hang a pair of antique skis on the wall. I told her I needed a new 12" compound miter saw to do that. That silver bullet only worked once... But, I still have my miter saw :)
 
Looking at CNC routers, it looks like I can spend about $150 for a Vevor or Sainsmart 3018 Pro, or I can build an even better one, starting with a router such as a Makita or DeWalt.

I'll probably do the second option.
I have had both the Dewalt and Makita - I recommend the Makita. They have lasted longer for me (in a CNC router) and have a wider range of speeds available.

https://www.amazon.com/Makita-RT0701C-1-1-Compact-Router/dp/B00E7D3V4S

If you are looking for a good entry level CNC, I have been using various models of Carbide 3D's Shapeoko for years and have been pleased.
 
If you are really good, you can modify the DIY CNC machine to do your slot cutting...
 
That's what I was thinking. A jig to hold the airframe under the CNC and Bob's yer uncle!
You can use the router to cut out the parts for the jig. But nepotism is unethical.
My wife once asked me to hang a pair of antique skis on the wall. I told her I needed a new 12" compound miter saw to do that. That silver bullet only worked
once... But, I still have my miter saw :)
My mother had been pestering my father about some bookshelves to go in a corner. I'm sure she would have been happy with purchased shelves, but my father wanted to make them himself. One Christmas, a nicely wrapped table saw showed up as a present, for my mother. As I recall, she was not particularly amused. Eventually, my dad used the saw when making the bookshelves, but I think it took a while. I inherited them. They are a real pain to move and I have to be careful because some of the shelves are slanted outwards!

When I was a kid, we moved into a house that had some skis on the wall, a yoke for oxen, and some snowshoes, all painted a dull red. They all were taken down eventually. I even used the snowshoes once or twice.

I don't have to take much trouble to get more tools. Many people I knew have died, and now I have some of their tools. Including the table saw used to build the shelves mentioned above. That's in the garage, where there's also a portable. And my father in law's table saw is in the basement. Lots of tools from guys in clubs I belong to as well. None of them all that fancy, though.
 
A dremel with a 545 diamond cutting wheel will work well. At least for a couple of tubes. The EZ402 with EZ546 wheels are cheaper and the wheels are replaceable. Also a 402 mandrel and cutting wheels will also work well.

Just mark the slots well, take your time and you can cut them out by hand in a lot less time than it takes to make a jig for other tools. A course flat file will clean up the slots well.
 
A dremel with a 545 diamond cutting wheel will work well. At least for a couple of tubes. The EZ402 with EZ546 wheels are cheaper and the wheels are replaceable. Also a 402 mandrel and cutting wheels will also work well.

Just mark the slots well, take your time and you can cut them out by hand in a lot less time than it takes to make a jig for other tools. A course flat file will clean up the slots well.

This is good advice and true.

Generally, for me, time is not necessarily my driving factor - I just enjoy building things, so building the jig is part of the fun! My biggest problem is that I need a storage unit to store all the jigs from over the years... 🤔

One rocket project usually sends me into 10 different tangent projects...
 
A dremel with a 545 diamond cutting wheel will work well. At least for a couple of tubes. The EZ402 with EZ546 wheels are cheaper and the wheels are replaceable. Also a 402 mandrel and cutting wheels will also work well.

Just mark the slots well, take your time and you can cut them out by hand in a lot less time than it takes to make a jig for other tools. A course flat file will clean up the slots well.

I agree with this. I was very nervous to cut FG slots with a Dremel, but I had no trouble using stacked cutting wheels and taking it slow.
 
There have been some vendors who have sold disks that are strong enough without stacking. These are much nicer than the skinny ones that shred if you look at them funny, but they do cut a wider kerf.
 
You all give me ideas....

I think I'm still going to get a Makita trim router and I've bought plans for a slot jig from Macklin Missle Works (as well as the Guillotine Fin Jig plans) and will probably eventually build a MPCNC Primo so I can also cut out fiberglass fins, etc. However, tomorrow I'll probably stop by Horrid Fright and buy some Dremel diamond cutoff wheels and play with that.
 
I stacked 3 and got exactly 1/8" slots.
And got 50 percent more itching dust than if you had cut two slots close together. A lot more than if you were enough of a wizard to cut slots with the old style discs. ;-p I think they might have been less than 1/32" thick and prone to shattering.
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Do the diamond wheels actually hold up better? It's not like you're cutting titanium nitride or something.
 
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