Looking for a Jig

[SAC of MMMSClub]

Yes I searched first and with varied wording!:bangpan:

I am looking for a fin jig for sanding a long bevel on the leading edge. Like a nike booster. Looking to see if someone has already come up with one so I do not waste time reinventing the wheel.

Want to be able to sand one side flip and sand other and get same results both sided, as in area beveled and angle of bevel. I have a bench belt sander and can get that to almost hold 90 deg. but I have to check it often and only the table and platen are 90 belt is ~ floating.

I am not looking for a steep angle on the leading edge.

I am using balsa so it may be hand sanded but still looking for some jig to assure close results on both sides.

Thank you, you may fire when ready.

 

[cwbullet]

This might cause inspiration.

https://www.jcrocket.com/finbevels.shtml

And

https://archive.rocketreviews.com/featured/tip_featured2.shtml

 

[tfish]

here's a video of me using my buddies jig.

[video=youtube;WSI9--ClSYc]https://www.youtube.com/watch?v=WSI9--ClSYc[/video]

Tony

 

[Gary Byrum]

Yes I searched first and with varied wording!:bangpan:

I am looking for a fin jig for sanding a long bevel on the leading edge. Like a nike booster. Looking to see if someone has already come up with one so I do not waste time reinventing the wheel.

Want to be able to sand one side flip and sand other and get same results both sided, as in area beveled and angle of bevel. I have a bench belt sander and can get that to almost hold 90 deg. but I have to check it often and only the table and platen are 90 belt is ~ floating.

I am not looking for a steep angle on the leading edge.

I am using balsa so it may be hand sanded but still looking for some jig to assure close results on both sides.

Thank you, you may fire when ready.

Hey bud, part of the whole building experience and craftsmanship is bordered on applications like beveling fins. Balsa is easy. Why would you want to escape part of the craft with a quick and easy way out? If it were about plywood, I'd understand better but seriously... I'm sure sanding is not most rocketeers favorite part of the build but there's a lot of it and it has to be done. My way of getting this job done is laying my fin on the edge of the bench, and with a sanding block, I work those leading and trailing edges. Sure, it gets a little tiring, but you did it. Not some kind of jig helper. Hang on to your skills. Don't give in to "the easy road."

 

[SAC of MMMSClub]

Hey bud, part of the whole building experience and craftsmanship is bordered on applications like beveling fins. Balsa is easy. Why would you want to escape part of the craft with a quick and easy way out? If it were about plywood, I'd understand better but seriously... I'm sure sanding is not most rocketeers favorite part of the build but there's a lot of it and it has to be done. My way of getting this job done is laying my fin on the edge of the bench, and with a sanding block, I work those leading and trailing edges. Sure, it gets a little tiring, but you did it. Not some kind of jig helper. Hang on to your skills. Don't give in to "the easy road."

It is not about not using me power to make the sanding block go to and fro, it is more about wanting to have the results be more uniform, other than that i agree with you.

 

[Gary Byrum]

It is not about not using me power to make the sanding block go to and fro, it is more about wanting to have the results be more uniform, other than that i agree with you.

That's where the craft comes into play. NOTHING will ever be perfect. But understand this, when you work the edges of your fins, you should compare all of them to each other. Getting consistency is important. I'm sure that is what your goal is, eh? Do you want all of your leading edges to be the same for all of your rockets? I don't. Some are rounded. some are simi-sharp, and some just edges rounded. It all depends on your expectations.

 

[SAC of MMMSClub]

That's where the craft comes into play. NOTHING will ever be perfect. But understand this, when you work the edges of your fins, you should compare all of them to each other. Getting consistency is important. I'm sure that is what your goal is, eh? Do you want all of your leading edges to be the same for all of your rockets? I don't. Some are rounded. some are simi-sharp, and some just edges rounded. It all depends on your expectations.

my expectations are to put a 3, 6, 12 mm thick pc. of balsa or plywood in this jig, and secure the pc., and gently massage the edges i want beveled with sand paper on both sides so that they are even.

From the edge to a desired depth back from the leading edge.

The bevel angle can be changed for different contours.

I have almost got it worked out. smoothness and aerodynamics as well as end finish are important too. I will have done the work, just need a little help holding the work pc. the same way every time its worked.

 

[fulldec]

I am not sure what you have in mind, but remember that you don't necessarily have to cut the root edge until you have finished shaping. That may possibly give you something with which to secure the fin.

Please share the results of what you come up with, or even the in-process design, perhaps the hive can help.

Don

 

[SAC of MMMSClub]

I am not sure what you have in mind, but remember that you don't necessarily have to cut the root edge until you have finished shaping. That may possibly give you something with which to secure the fin.

Please share the results of what you come up with, or even the in-process design, perhaps the hive can help.

Don

I was given a flash of inspiration by Gary saying edge of bench.

I am thinking of a pc. of 3/4 plywood about 10"x10" with some holes like a tombstone to allow for holding and securing of work pc.

A metal front edge and some way to set angle of sanding block.

I think I will hold fin by root edge.

Some fins taper fwd and aft some taper in all three directions.

Something that i am looking at is balsa is more flexible than plywood so have to be careful of how to hold and not crush or break.

I worked with a Matson surface grinder when i was pretending to be a machinist helper, and liked the idea of making a system that shows you when you are done sanding to level you want, like how we would paint a block with blue dykem and grid down to it.