How to accurately bevel fins

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After trying many jigs, I think this router jig is the best. I'm going to convert my belt sander jig to a router jig like yours. I used John Coker's method. https://www.jcrocket.com/finbevels.shtml. Here's a picture of my belt/disc sander jig.
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I see this is the best way to bevel fins, no sanding discs to replace and it is more precise.

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Base plate of 1/4 Masonite with white coating.

new fence 2.jpg
One continuous piece of 1/2' particle board, white shelving. Notch around router bit. Attache with screws.
The base plate and fence give a smooth slide across the machine.
No matter how hard you try it is difficult to align separate fences to run smoothly.

using new jig.jpg
Feed slowly, run it through twice and it will do fine work.

Beveled Fin.jpg
Flawless edges on plywood and G-10.
I've worked in a machine shop and with careful cutting techniques it rivals a CNC machine for thousands less.
It will bevel fins for a long time. I've cut many G-10 fins for a dealer and still cut my own over and over.

WHAT YOU NEED: (All can be found at Lowes or Home Depot except the router bit.)

1 Ryobi router table-------- $99, less on Craigslist, ~$50
1 - 1.5-2HP Ryobi router--- $69-99, less on Criaglist, ~$50
1/4" and 1/2" white board--
15 deg router bit------------ $29, Woodcraft store
 
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I see this is the best way to bevel fins, no sanding discs to replace and it is more precise.
And the advantage of the router jig is you can't OVER sand. With my disc sander I have to reposition my hands while pushing the fin through. If I bump the fin toward the disc I leave a gouge. That can't happen with the disc sander.
 
Hey all, I finally got a router and tested it out. Yikes. Results were inconsistent to say the least.

First, I didn't use a jig. I used a 45° and a rounding bit as my test. Used lite ply at max RPM. Seemed to sort of peel off rather that cut. When I was done, the cut was uneven. It started about 1/3 of the way up on one side and 2/3 the way up on the other. Checked level, dead on.

So I tried different techniques. Fed slower, faster, hands close, hands spread apart... different things to see if I could apply even force and keep wood flat. Just wouldn't keep straight.

So, my thought is the wood has a slight warp or my technique is off. Any advice for a novice?
 
Hey all, I finally got a router and tested it out. Yikes. Results were inconsistent to say the least.

First, I didn't use a jig. I used a 45° and a rounding bit as my test. Used lite ply at max RPM. Seemed to sort of peel off rather that cut. When I was done, the cut was uneven. It started about 1/3 of the way up on one side and 2/3 the way up on the other. Checked level, dead on.

So I tried different techniques. Fed slower, faster, hands close, hands spread apart... different things to see if I could apply even force and keep wood flat. Just wouldn't keep straight.

So, my thought is the wood has a slight warp or my technique is off. Any advice for a novice?
Odds are the warp was caused by hand pressure alone, or the wood could be warped too. It is possible to use double sided carpet tape ( not the super sticky one) to attach the fin to a larger piece of wood that will support it better and allow better control across the router base, even better is to use a router in a router table, freehand routing on smaller pieces is difficult due to the difficulty of holding the router steady as parts of the base move on and off the fin.
 
Hey all, I finally got a router and tested it out. Yikes. Results were inconsistent to say the least.

First, I didn't use a jig. I used a 45° and a rounding bit as my test. Used lite ply at max RPM. Seemed to sort of peel off rather that cut. When I was done, the cut was uneven. It started about 1/3 of the way up on one side and 2/3 the way up on the other. Checked level, dead on.

So I tried different techniques. Fed slower, faster, hands close, hands spread apart... different things to see if I could apply even force and keep wood flat. Just wouldn't keep straight.

So, my thought is the wood has a slight warp or my technique is off. Any advice for a novice?

I don’t have any advice, but just yesterday, I asked a friend to help me add a rounded bullnose to some 3/8” ply. He used a router, and it turned out perfect. I don’t own good tools, and I’m not an experienced or skilled user of tools, so I can’t say I know anything about it, but he did a great job.
 
Odds are the warp was caused by hand pressure alone, or the wood could be warped too. It is possible to use double sided carpet tape ( not the super sticky one) to attach the fin to a larger piece of wood that will support it better and allow better control across the router base, even better is to use a router in a router table, freehand routing on smaller pieces is difficult due to the difficulty of holding the router steady as parts of the base move on and off the fin.

I use double-sided tape to hold the stack of fins together. That way my router bit follows the contour. I have been able to get a pretty good rounded edge, though a few spots often take a little hand sanding after routing. These spots usually occur where I had to pause with the router to change direction around a curve.

ImageUploadedByRocketry Forum1481848300.976001.jpgImageUploadedByRocketry Forum1481848322.985695.jpgImageUploadedByRocketry Forum1481848342.339782.jpg

Edit: I just realized that I posted some of this earlier in this thread. Sorry to be redundant.
 
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Hey all, I finally got a router and tested it out. Yikes. Results were inconsistent to say the least.

First, I didn't use a jig. I used a 45° and a rounding bit as my test. Used lite ply at max RPM. Seemed to sort of peel off rather that cut. When I was done, the cut was uneven. It started about 1/3 of the way up on one side and 2/3 the way up on the other. Checked level, dead on.

So I tried different techniques. Fed slower, faster, hands close, hands spread apart... different things to see if I could apply even force and keep wood flat. Just wouldn't keep straight.

So, my thought is the wood has a slight warp or my technique is off. Any advice for a novice?

Its a little hard to follow your description, but it might have been climbing. Which way were you moving the stock (or the router)?

https://www.finewoodworking.com/2014/05/07/router-accident-is-a-great-lesson-in-climb-cutting

https://www.woodmagazine.com/woodworking-tips/techniques/routing/climb-cutting
 
I made a very simple jig that I can clamp to my disc sander. It is a length of aluminum L with a notch cut into it and a length of hardwood (mine is L shaped, but probably does not have to be. You adjust the gap between the AL and wood so the fin slides but does not have excessive slide play. And then set the angle of the jig relative to the disc to change the bevel angle and depth of bevel. I've used it on everything from thin G-10 to thick plywood. I do two passes on each side to get a smooth finish. I hope the photos help.

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Odds are the warp was caused by hand pressure alone, or the wood could be warped too. It is possible to use double sided carpet tape ( not the super sticky one) to attach the fin to a larger piece of wood that will support it better and allow better control across the router base, even better is to use a router in a router table, freehand routing on smaller pieces is difficult due to the difficulty of holding the router steady as parts of the base move on and off the fin.

It is mounted on a table. I doubt I have the skill to try and do this without a table.

Its a little hard to follow your description, but it might have been climbing. Which way were you moving the stock (or the router)?

https://www.finewoodworking.com/2014/05/07/router-accident-is-a-great-lesson-in-climb-cutting

https://www.woodmagazine.com/woodworking-tips/techniques/routing/climb-cutting

I'm feeding in the direction that the manufacturer recommends... right to left.
 
The "peeling" thing is hard to figure. If the bit is sharp, you should be making chips and saw dust, and the cut shouldn't move up and down on the edge of the work piece.

I am bound to ask: did you lock the height of the router? (I am guessing you would notice if the router bit was rising and falling while you cut).
 
The "peeling" thing is hard to figure. If the bit is sharp, you should be making chips and saw dust, and the cut shouldn't move up and down on the edge of the work piece.

I am bound to ask: did you lock the height of the router? (I am guessing you would notice if the router bit was rising and falling while you cut).
First thing I checked before checking table was flat. Bit was locked in place. One thing I had to do was move my fence to allow the bit to spin. It was separated by about two inches to allow the bit to spin. My table has measurement marks to ensure it is even on both sides.

I figured out what the peeling was. It was indeed saw dust just large amounts at once.
 
It is mounted on a table. I doubt I have the skill to try and do this without a table.



I'm feeding in the direction that the manufacturer recommends... right to left.
Check out my modified router table I setup for beveling fins in "Show me your jigs and Such". With a continuous fence, no skips and no jumps. You can connect a small shop vac to most router tables to clear a lot of debris. An old miter box trick is to put a chamfer on the bottom edge of the fence. That allows some debris to hide and not push your piece out from the router bit.
 
Check out my modified router table I setup for beveling fins in "Show me your jigs and Such". With a continuous fence, no skips and no jumps. You can connect a small shop vac to most router tables to clear a lot of debris. An old miter box trick is to put a chamfer on the bottom edge of the fence. That allows some debris to hide and not push your piece out from the router bit.

I ran so many fins for myself and a dealer through my last jig I cut a groove across the base plate.
I never had to replace the bit and I did A LOT of g-10 beveled fins.
I sold it and built the new one. That is why I have a replaceable fence and base ( low cost and easy to replace)
For round-over edges, I use a Ryobi battery router, very carefully and it comes out just fine.

I use that same router in my new tubing slotter, from 1/8" up to 1/2" wide slots.

Infinity Tools, fluting jig, has roller bearings for smooth glide, $79.00

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Check out my modified router table I setup for beveling fins in "Show me your jigs and Such". With a continuous fence, no skips and no jumps. You can connect a small shop vac to most router tables to clear a lot of debris. An old miter box trick is to put a chamfer on the bottom edge of the fence. That allows some debris to hide and not push your piece out from the router bit.
Your setup (https://www.rocketryforum.com/showthread.php?p=1576854) is almost exactly what I have. I'll have to look at the continuous fence when I get home. Your bevels look awesome and exactly what I want.

Noob question. Are you supposed to run the fin along the fence or the tabletop? I was laying them on the tabletop, flushing edge with fence.
 
II haven't tried this but I think I read it somewhere or else I wouldn't be able to relay this to you......

Make a jig by attaching two pieces of wood together in the angle of the desired bevel. Glue your sand paper to the wood and use like a sanding block. Consistent sanding (i.e. the same pressure and number of strokes) should result in the same bevel for all fins. haven't tried this but I think I read it somewhere or else I wouldn't be able to relay this to you......

Make a jig by attaching two pieces of wood together in the angle of the desired bevel. Glue your sand paper to the wood and use like a sanding block. Consistent sanding (i.e. the same pressure and number of strokes) should result in the same bevel for all fins.
 
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