Laser Cut Balsa, Love or Hate?

Sheryl@semroc said:

When we first started back up, I remember the discussion about laser cut fins. We watched the thread because many did not like the pre-cut fins. Carl decided to keep cutting the fins and for the "die-hard do-it-yourselfers", a template was provided if you wanted to cut your own. As years passed and some of the fins became more complicated, most were pleased we provided this service.

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If you wouldn't have had laser cut parts for that Mars Lander I built (and subsequently broke after one good flight and one bad one) I'd probably be in an "institution" with an I-Love-Me jacket on licking the walls.

In other words...the laser cut parts were most appreciated.

-Dave

I think whatever way work for you is best. There is more than one way to skin a cat and finishing balsa fins has always been one of those topics of discussion on this forum. Some like to use thin down glue, while others prefer dope sealer and still others like to paper the fins. I say if you like the results stay with it, but be open to try other methods

I glass all of my balsa fins with lightweight cloth anyway, whether they are laser cut or cut from stock.
So much easier than papering or fooling around with fillers.
I don't know why everyone does not glass balsa fins.:confused2:

Wow, that's a lot of posts for an old thread... but as it's been revived, I'll toss in my $.02.

Typically, I either am upscaling something, or cloning things, so I'm pretty happy with cutting my own. That said, when I get a kit, I appreciate the precision of the laser cut fins, and I hate when diecrushed fins (or Guillow's bulkheads) are sent without any apparent quality control.

I've noticed something though lately about Estes' balsa. It seems to me to be consistently better these days than 20 years ago. Does anyone know why?

TopRamen said:

I glass all of my balsa fins with lightweight cloth anyway, whether they are laser cut or cut from stock.
So much easier than papering or fooling around with fillers.
I don't know why everyone does not glass balsa fins.:confused2:

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Eh, I've never felt a need to paper fins on an lpr unless they are of a shape that would be prone to braking (long and thin, etc.). Sure I've broken a fin before (not a hard fix), but it was on a fin that I knew I should have papered—and a fin shape that I designed. Fiberglass adds weight that's hard to overcome with LPR motors/rockets. I've noticed lately that the lighter rockets I've been building recently (less primer, enamel and clear coat=significantly less weight) have noticeably better performance than my earlier rockets where I painted the heck out of 'em.

But hey, to each their own—it's what makes the world go 'round.

I have no beef with LC parts, in fact when I discovered that one can buy a stick&paper airplane kit, I was inclined to buy one(cutting ribs always gave me problems).
Rex

Laser cut parts: love them.
Quality of balsa/tung in Estes and Custom kits: meh.

Definitely a laser cut.


TA

Gary Byrum said:

X-Acto knives were recommended and about all we really had to work with in those days along with single edge razor blades....yuckers on both of those tools. After many years of graphics applications, I discovered how well I liked a good quality breakaway knife and a ruler with a metal edge. I can make the best balsa cuts with these and they support the note, "having the proper tools" to execute the job at hand. If I still had to use X-Acto's, I'd be all over the LCB's as well. Kudos to owning a Dremel also! Here's my knife of chioce. The saw on the bottom is also a nice cutting tool.

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I agree with you 100%. I have a Scotch Titanium breakaway knife, best invention ever! It will slice through 1/4" balsa like a knife through butter (all puns intended).

I recently have gotten back into the hobby and while laser cut can be a help I am finding it more of a hinderance. I use 'glue sizing' also as "Woody Workshop" started the post with. My problem with laser cut is that in order to reinforce the end grain you have to remove the char and you wind up sanding a lot of the fin off. So the point of the laser cut was?

My scratch built ATD (see thread) was hand cut fins with glue sizing. I watched, with dread, as it headed towards a walking path from 800' on a 15 mph day landing fin corner first (of course:eyeroll. When I went to retrieve my crash victim I found the ventral fin had a 1/32 x 1/32 ding on the very corner. That was the extent of the damage. So the 'glue sizing' reinforcement works well to keep the fins from being mangled.

I agree with another poster that the 'correct' knife to cut your wood with is one of the new breakaway knives. I use the Scotch Titanium refillable. This thing will almost cut steel! I cannot recommend these enough, slices through end grain like it was a sheet of paper.

The balsa in some of the kits is marginal, at best. I just received an order from Midwest Products and the quality of balsa is exceptional, tightly grained and straight as hell. It will be a pleasure to work with this stuff. If kits were made with this then they wouldn't 'crash and burn' after a few flights.

Okay so plug me into the group that enjoys the build as much as the flight.

For me, it depends.

If the fins primarily have straight edges I don't mind cutting them myself.

For complex units I'm happy with laser cut. I am presently building the Estes Asteroid Hunter. The difficulty of all of the cuts would be beyond me, and I think most builders. The LC cuts parts fit together perfectly - I was amazed at the precision of the design and LC cuts.

I enjoy the building part. But for the most part I would prefer LC fins

But for each person there is a level that they are willing to go. Having LC fins does make life easier, unless you don't like the material or want to copy/enhance the fin.
Some folks may make their own body tubes, I think most don't (for lpr excluding competition rockets).
Some have the skills and tools to machine their own nose cones, again many don't.
Some go for the perfect, showroom finish - others fly the rockets "naked"
Some like to build their motors, other prefer the simplicity of CTI motors.

There is no one solution for our community.....
And in many ways I am glad - I enjoy seeing the diversity (so long as we can accept the differences and not get into battles over the "right way")

Laser cut fins?....absolutely love it, great idea. I could never get perfect straight solid cuts, then i'd have to sand, trim, etc, saves a lot of time and aggravation.

JPVegh said:

One of these days I'll get my own laser cutter. It's just a matter of time before they get cheap.

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It depends on how you define "cheap", but Rockler just introduced a desktop laser cutter that looks to be roughly the size of an inkjet printer. It runs about $3850. For me, it has to get under $2000 before I'm ready to pull the trigger. And I need to figure out how my wife could benefit from one, so I could buy it "mainly" for her crafts, and I'd use it too.

I did work for a prototype shop several years ago and had access to laser cutter and CNC. By far the laser was more useful for rocket stuff. I made numerous centering rings, and some tabbed fins for TTW attachment. I can still use the equipment, but it's a 30 mile drive one way. I want my own!

OOoh! I love laser cut balsa fins!

In fact, I love laser cut fins so much that I bought my very own laser! https://www.flickr.com/photos/oflittleinterest/sets/72157624827094977

There are some caveats though. Laser cut balsa doesn't have a 90 degree edge - there's a very slight angle due to the way the laser works, so you have to spend a bit of time sanding that out. And you do need to make sure the grain is correctly aligned.

I guess for me, it's a very expensive Xacto knife

If you were asking for die-cut vs fin template, I'd take the template any day and cut it by hand - as I did for the first years of building rockets.

On a side note, here's a few things that I've done with it -

Cluster Spool Rocket - https://www.flickr.com/photos/oflittleinterest/sets/72157633645257829
Blue Bird Zero upscale - https://www.flickr.com/photos/oflittleinterest/sets/72157632398661329
Geek Rocket (for a competition) - https://www.flickr.com/photos/oflittleinterest/sets/72157629860258065

Krusty

I love laser cutting. Consistent edges and complex parts are cut with a precision that is tough to match by hand. The interlocking scoops on the QCC Explorer, for example, were a breeze. Without laser cutting, they would have required a lot more alignment work. I like the satisfaction of cutting my own stuff too, but laser cut parts in a kit make the build a real pleasure.