Any reason I shouldn't use some old circuit boards for rocket fins/parts? They're all lead free. Some are probably a bit heavy, from the thick planes inside. 
Beveling G10 and carbon and plywood fins - what do you want to know?
- Thread starter rfjustin
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We still have had little discussion on which router bits work best, or specifics of them. Same goes with router speeds that work best.
Same goes with router speeds that work best.waltr
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Would work but as you said, heavy due to internal copper.Any reason I shouldn't use some old circuit boards for rocket fins/parts? They're all lead free. Some are probably a bit heavy, from the thick planes inside.
waltr
Well-Known Member
Yes, please bits and speed discussion.We still have had little discussion on which router bits work best, or specifics of them.
I use the Dremel Router with a 'cone' bit to bevel fins. Must go slow and only take off a little at a time but do end up with uniform bevels. Set speed to just under mid setting.
rharshberger
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Speed of bits is highly variable, in a table mounted router they are going to be based on bit diameter (larger diameter bits at lower rpm due to vibration) feed rate and material, in a handheld tool whats controllable and keeps the bit from loading up. Speed really isnt one size fits all, learn your tool and how you interact with it then tune from there.We still have had little discussion on which router bits work best, or specifics of them.
Here is the bit I use, got it at Rocker through the mail. You don’t need the pilot but since I often don’t make bevels that wide I haven’t found the need to remove it.
As for speed, I use a regular single speed router that spins at 21,000 rpm. Flute loading isn’t an issue for a large two flute bit like this. I wouldn’t worry about speed so much in this application.
I know some advocate for special coated bits and burrs. I think they are a waste of money in this application. Carbide is infinitely harder than wood, fiberglass or carbon fiber. Just get a cheap bit like this, will likely last a lifetime. If your router can take a 1/2” shank bit, select it over the 1/4” shank stuff, they are much more rigid and give a better finish.
As for speed, I use a regular single speed router that spins at 21,000 rpm. Flute loading isn’t an issue for a large two flute bit like this. I wouldn’t worry about speed so much in this application.
I know some advocate for special coated bits and burrs. I think they are a waste of money in this application. Carbide is infinitely harder than wood, fiberglass or carbon fiber. Just get a cheap bit like this, will likely last a lifetime. If your router can take a 1/2” shank bit, select it over the 1/4” shank stuff, they are much more rigid and give a better finish.
Wonder what happened to Justin and all his information? 
bibbster
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Maybe he went a different route. 
rfjustin
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I have not had any time to work on the new router yet, coming soon...Wonder what happened to Justin and all his information?
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...says the guy using a wobbly garbage can as a router table, LOL!
The Kobalt table and router combo idea probably came from me. For the price, it isn't bad.
This post give some of my lessons-learned on beveling fins - bits, safety, and the table
https://www.rocketryforum.com/threa...nd-ended-up-with-all-this.164099/post-2092507
I got a Peachtree router table top a while back and it has been great. A little more expensive than some of the other option here, but I do enough woodworking to justify it. Pic posted here from when I first built it: https://www.rocketryforum.com/threads/blackfish-l1-super-dx3-build.163514/post-2085472
I did not pay $255 for it, but got the Ultimate here: https://www.ptreeusa.com/rtr_router_tables.htm
I did not pay $255 for it, but got the Ultimate here: https://www.ptreeusa.com/rtr_router_tables.htm
Wish i had the room right now for a set up. Until we get the new house im limited. Definitely have some fins id like beveled better then they were.
rfjustin
Well-Known Member
New to me table came like this, notice the plastic gate and plastic yellow/orange insert around the bit.
rfjustin
Well-Known Member
As compared to my old table, I ditched the rear gate and used a 2" aluminum angle iron instead, and filled the well with epoxy, then came back and lightly sanded the top. Goal here was a smooth surface...
rfjustin
Well-Known Member
Regarding bits and speeds, both of by routers and have two speeds, on and off. I've never had the need to adjust the speed, nor the ability to with these tools. My go to bit(s) are Foredom Typhoon. The fine tooth 15 degree is my go-to, A-KB14159
I've used their 5 degree fine tooth bit as well, but those bits get trashed quickly.
I've never had the need to adjust the speed, nor the ability to with these tools. My go to bit(s) are Foredom Typhoon. The fine tooth 15 degree is my go-to, A-KB14159I've used their 5 degree fine tooth bit as well, but those bits get trashed quickly.
rfjustin
Well-Known Member
Some questions that were posed that I should be able to answer later today during a beveling session:
How do you determine initial cut? Do you run a test piece?
How beveled is beveled enough?
How exactly do you ensure the bevel is symmetric?
How do you determine initial cut? Do you run a test piece?
How beveled is beveled enough?
How exactly do you ensure the bevel is symmetric?
Justin, you are asking for trouble if you are planning to run your stock between the rotating bit and the fence. Definitely not safe and the main reason all commercial router tables like the one you have employ a split fence so you can bury the bit in the fence. Consider what will happen if you slip or the work catches and kicks back. Please rethink your approach and be safe. Your 28,000 rpm router will cheerfully rout your fingers as well as it does g10 or plywood.
rfjustin
Well-Known Member
Thank you for the feedback.
I've been doing it for 10 years with safe results. While I appreciate the concern I think there is a magic combination from stepped cuts and a steady feed rate. This thread is not intended as a "you should do what I do", but more of an info dump on what has worked for me. As always, YMMV.
Best,
On the topic of routing and beveling, I tried something for the first time on a LOC Doorknob build that I really like and thought I would share. When you are beveling fins, you either are left with a flat profile where the two bevels don't meet, or, you bevel to a point which is fragile. Neither are good solutions in my opinion.
I tried something different on this build and used a 3/8" cove bit to first put a round profile on the fins, and then follow that up with bevels to suit. It makes a pretty sweet looking fin when finished. Since the baltic birch I used for the fins is just under .375", it worked out perfect. if there is a little mismatch, it's not a big deal as that area get removed anyway when doing the bevels.
I tried something different on this build and used a 3/8" cove bit to first put a round profile on the fins, and then follow that up with bevels to suit. It makes a pretty sweet looking fin when finished. Since the baltic birch I used for the fins is just under .375", it worked out perfect. if there is a little mismatch, it's not a big deal as that area get removed anyway when doing the bevels.
Justin,
That's great and I'm glad it has worked out for you. BUT, keep in mind that not everyone has your level of skill (or luck) and it's important to call out the inherent lack of safety in that approach. I'm sure you would feel terrible if someone lost a few fingers based on following the approach that has worked for you.
Not intended to sharp shoot you or throw shade, but to serve as an EXTREME CAUTION for anyone looking to replicate your work.
rfjustin
Well-Known Member
Hence my very obvious disclaimer offered: "This thread is not intended as a "you should do what I do", but more of an info dump on what has worked for me."
rfjustin
Well-Known Member
Straighten the gate, positioned for a very light cut on the material. I also knock the edges off all sides of the fin in question. I simply raise the bit a quarter turn each pass as needed. How much meat you leave is somewhat dependent on personal preference.
rfjustin
Well-Known Member
I prefer to take a single-piece fence, notch just enough for your bit. Trying to align 2 fences perfectly is near impossible. I use a piece of melamine on the bed, too. Cutting a lot of FG overtime will cut a groove in the bed of the router table. Once it wears its easy to replace the melamine. I've made a lot of FG fins (some plywood) for a dealer and my self, maybe 350+ bevels using a $100 router table and Ryobi 1/2" router, refining all the mods and techniques over time.
Dave,
A first rate approach. I don’t do as much beveling as you, but I also use a continuous fence. I just took a piece of 6/4” maple and used a Forster bit to make a cavity for the bit to spin in. It’s very effective and above all doesn’t expose me to the dangers of an exposed cutter.
A first rate approach. I don’t do as much beveling as you, but I also use a continuous fence. I just took a piece of 6/4” maple and used a Forster bit to make a cavity for the bit to spin in. It’s very effective and above all doesn’t expose me to the dangers of an exposed cutter.
A safety rule I follow with tools like these is: No gloves, other than surgical. Real gloves will happily drag your whole arm across the tool if they can. Surgical gloves just disappear.
How do y'all typically deal with thinner (1/16") FG fins? Not much meat for much of a bevel -- least without compromising strength I would expect...
I was thinking about 1/8" FG fins the same way, and how do you not end up with a sharp knife edge after beveling?
Is this all worth the extra 10 feet in altitude you would gain?
rfjustin
Well-Known Member
Well, 1/16" is hardly worth the effort IMO. I've used a 5 degree bit on .125 and .0625 G10 with good results, but the 5 degree bits get ground down by the G10 pretty fast. Fin pic below is 0.125" thick G10 with 5 degree bit.
