Cutting Fins From Raw Balsa Stock

[Daniel Runyon]

I'm about to be ordering our first kits that require you to cut your own fins out of raw balsa stock and was wondering:

What tools? I have an X-acto #1 with #11 blades (thanks cjl for your tip on the Estes forum!)... is that fine or should I get a razor saw? What size and tooth number is the right kind of razor saw? Where in the heck do I find a metal ruler these days?!?!?

Really, any tips and tools you could recommend for a complete newb at this (all I've done so far is use the X-acto to finish the cutting on some lazer cut kits) would be much appreciated!

For anyone who's interested in the least, I think I'm going to pick up a couple of Zooch kits... the Mercury Redstone and the Saturn V, and I've got my eye on a couple of PRD's.

Much appreciated!
Daniel

[CPMcGraw]

I'm about to be ordering our first kits that require you to cut your own fins out of raw balsa stock and was wondering:

What tools? I have an X-acto #1 with #11 blades (thanks cjl for your tip on the Estes forum!)... is that fine or should I get a razor saw? What size and tooth number is the right kind of razor saw? Where in the heck do I find a metal ruler these days?!?!?

Daniel,

Absolutely, a fresh #11 blade is fine for this job. Just don't try to make a complete cut in one pass -- let the knife do the work, not your hand. Make several passes until the wood is cut through. Change the blade if it starts getting difficult to make a clean cut. As for razor saws, they are good for cutting through blocks, but not for fins like what most of our models use.

Here's a tip: Print a pattern for your fins onto label paper, just like they would be laid out on the balsa sheet. Apply the label to the sheet first, apply a blank label on the opposite side, and gently burnish them down to make a sandwich. Now, cut through that sandwich, using the ruler to keep the cuts straight. The balsa fin has now been cut and sealed in one step. Apply thin CA glue around the outer edges to "lock" the paper to the wood, and to harden the edges. Don't coat the root edge, though. You want the grain exposed for the yellow glue to penetrate.

As for the steel ruler, look in the model railroading section of your LHS. GENERAL makes a good 12" version for the various train scales. HELIX makes some cork-backed steel rules that can be found in STAPLES, OFFICE MAX, or OFFICE DEPOT.

Much appreciated!
Daniel

[Daniel Runyon]

HELIX makes some cork-backed steel rules that can be found in STAPLES, OFFICE MAX, or OFFICE DEPOT.

Thank The Maker for that... we have no LHS around here! Much appreciated, I'm glad to know the #11 will handle it... all budget can go to kits rather than supplies!

Thank you very much,
Daniel

[JRThro]

Thank The Maker for that... we have no LHS around here! Much appreciated, I'm glad to know the #11 will handle it... all budget can go to kits rather than supplies!

Thank you very much,
Daniel
One problem I have every time I need to cut out fins from balsa stock is keeping the blade straight. So most of the fins I cut out have angled edges to them before I sand them. I'm not sure how to prevent that from happening.

Also, yes, use a steel straightedge. I have a small piece of aluminum angle that I've used a few times, and the exacto knife shaves slivers of aluminum off it. Steel would definitely work better.

Good luck, and let us know how things go!

[CPMcGraw]

One problem I have every time I need to cut out fins from balsa stock is keeping the blade straight. So most of the fins I cut out have angled edges to them before I sand them. I'm not sure how to prevent that from happening.

I have the same problem, but usually the angle adds material at the bottom of the cut than at the top. Cut to the outside of the line, and sand it back to square after stacking them.

[JRThro]

I have the same problem, but usually the angle adds material at the bottom of the cut than at the top. Cut to the outside of the line, and sand it back to square after stacking them.
Man, I was hoping there was some really simple secret that I hadn't caught onto yet.
;) :cool:

[ShieldWolf]

I got my 18" steel ruler at WalMart, in the school supplies section, and a steel yardstick in the sewing section.

If you don't use the label suggestion, then try applying a layer of masking tape to the back of your balsa before cutting to help prevent splintering/breakage.

Use a piece of heavy cardstock, like the back from a notepad, as a cutting surface. There's no grain for your knife to follow, unlike a wooden cutting surface.

Beware cutting on the kitchen table, unless you have a VERY understanding S.O.! :o

HTH
Randal

[Daniel Runyon]

I got my 18" steel ruler at WalMart, in the school supplies section, and a steel yardstick in the sewing section.

Beware cutting on the kitchen table, unless you have a VERY understanding S.O.! :o

I'll cruise by Wal Mart and hope for the best... that's the only place we actually have in our own town without having to drive at least a half hour, and even then the pickins are slim (Home Depot and Lowes, but still no hobby shops at that distance)!

I do all of my modeling and cutting right here at my computer desk... yes, it's got cuts on it... but that's cool... I've got a tube of Elmer's Wood Filler and a bunch of sandpaper right here! I will indeed use a cutting surface for this though.

Much appreciated folks! The Zooch kits are on their way!

[CPMcGraw]

...I do all of my modeling and cutting right here at my computer desk... yes, it's got cuts on it... but that's cool... I've got a tube of Elmer's Wood Filler and a bunch of sandpaper right here! I will indeed use a cutting surface for this though...

I'm the same way -- working at my computer desk -- but I do protect the work surface. I use disposable kitchen cutting mats that I get from Wal Mart. They come three (or four) to a pack, and are about $3 a pack.

[Daniel Runyon]

I'm the same way -- working at my computer desk

It's pretty much the center of ALL operations! It's one of those angled corner desks and our bed is just to the left of it so my son can sit on the bed right beside me while we work on rockets and watch some space or sci fi movies.

I also make my living doing wedding videos here at the desk, and I keep the learning materials that my son and I work on here... Dr. Suess and other books (just got a level one reader called Rockets and Spaceships!), writing practice paper and word flash cards... we spend a LOT of time here at the desk! We've gotten our sanding mess containment and cleanup routine down pretty good now!

[barone]

.......I do all of my modeling and cutting right here at my computer desk... yes, it's got cuts on it... but that's cool... I've got a tube of Elmer's Wood Filler and a bunch of sandpaper right here! I will indeed use a cutting surface for this though.

Much appreciated folks! The Zooch kits are on their way!Well since you're going to Walmart anyway....In the domestics section, you can pick up a self healing cutting mat to use for a cutting surface (over the wood). Mine's a 12"X18". Brand name is Fiskars. I've had it for years and still can't make out all the cut marks. Comes with one inch squares pre-printed so you can use it as a ruler too (albeit not a steel ruler :rolleyes: ).

[bikegod]

and if you really are on a budget, a piece of scrap linoleum works fine too (if it isn't too curled that is).

I used to sew a lot and bought two of the roto-cutter mats (same as the Fiskars). One large and one small. That was 13 years ago and I am still using them. But I can't believe how much they cost now. Great investment though, and except for CA glues, I haven't gotten any other glues stuck to it (yet). They all seem to peel right off.

[ghost]

What's the best way to cut plywood (1/8"). The #11 xacto blade?

Thanks!

[CPMcGraw]

What's the best way to cut plywood (1/8"). The #11 xacto blade?

Thanks!

Short of a good laser :D , use a scroll saw. Don't even think about cutting it with the #11. I'd use this for both 5-ply birch and 3-ply white pine Lite Ply. Dress it up by cutting just outside the lines, then sanding it down to the line with some form of mounted disk or belt sander.

[handeman]

Short of a good laser :D , use a scroll saw. Don't even think about cutting it with the #11. I'd use this for both 5-ply birch and 3-ply white pine Lite Ply. Dress it up by cutting just outside the lines, then sanding it down to the line with some form of mounted disk or belt sander.

A hacksaw also works pretty well. It may take a while, but it does a pretty smooth cut.

When I sand the outside edges down, I always stack the fins together on the root edge, hold them tight and sand all the edges at one time, starting with the root edge. This makes sure all the fins are exactly the same size.

[Daniel Runyon]

I wound up really enjoying cutting my own fins. My wife picked me up a steel ruler at Wal Mart. I went to Michaels and got some balsa stock to make custom fins from... getting ready to take my first stabs at scratch building fairly soon!

I'm starting to think that lazor cut = lazy cut!

[jflis]

I wound up really enjoying cutting my own fins. My wife picked me up a steel ruler at Wal Mart. I went to Michaels and got some balsa stock to make custom fins from... getting ready to take my first stabs at scratch building fairly soon!

I'm starting to think that lazor cut = lazy cut!

THERE YA GO!

That is one of the MAIN reasons that most FlisKits models come with "cut your own" fins. It requires you to learn a very valuable skill. One that is a virtual neccessity when scratch building.

[foose4string]

And Jim likes to make it extra challenging by supplying some HARD balsa! Not complaining!!! I'll take the hard stuff over the spongy any day !!!! ;)
But man, that balsa stock in my Deuce kit was a bear to cut through, even with a fresh #11. :D

[pantherjon]

The balsa on my Flea was pretty soft, but was real straight :) Now, the 1/32" balsa I used on my X-Wing build to fill in the plastic fins was a REAL bear! I never thought something so thin would be so hard to cut! even with a brand new blade..Tried making the cuts with one pas-no go..Had to use the 'old fashioned' way, score the line, and work deeper with each pass of the knife.

[Tau Zero]

I'm starting to think that lazor cut = lazy cut!(chuckling) Well, if you're just cutting straight lines in moderately hard balsa, then I'd agree.

But if you like curvy fins, like these Centuri Nova recreations below... :rolleyes:

...Or if you insist on using basswood, well... :mad:


Let's just say I'm glad I know somebody who can help me out with laser cutting. :p :cool:

[Daniel Runyon]

Is there any way to salvage slightly warped (curved) balsa stock? I've got a few sheets from Michaels and got some more from Red Arrow (all Midwest stock) and if I set it flat on a table it either rises a bit in the middle or on the ends (depending on which way it's flipped, obviously).

[barone]

Is there any way to salvage slightly warped (curved) balsa stock? I've got a few sheets from Michaels and got some more from Red Arrow (all Midwest stock) and if I set it flat on a table it either rises a bit in the middle or on the ends (depending on which way it's flipped, obviously).
Usually, if you sprinkle it with a little water and then put a weight on it, it'll flatten out (sorta like re-warping but in the opposite direction....)

[Daniel Runyon]

Maybe misting it with a spray bottle? How wet would you want to get it and how long would you want to leave it weighted for it to be effective?

Also, in the link where you showed me the t-angle, where would one go to get some of those super handy looking glue syringes?

[barone]

Maybe misting it with a spray bottle? How wet would you want to get it and how long would you want to leave it weighted for it to be effective?

Also, in the link where you showed me the t-angle, where would one go to get some of those super handy looking glue syringes?Yeah, you don't want to soak it, just a misting. After all, it was probably a combination of moisture in the air and how it was stored that caused it to warp. How long? I don't know. Just check it after it's had a chance to dry our and see if the warp is gone.

As for the glue syringe....yeap, that little buger is really useful. Helps to get a nice controled filet and sometimes can reach those hard to reach places without using a dowel or swab. Mine came attached to a bottle of Aileen's Tacky Glue. Got it from Hobby Lobby.....(by the way, they have a 40% off coupon this week....)

[Daniel Runyon]

Much appreciated! It is quite a relief to find out that something can be done about it rather than just having to cut out the middle and use only the end pieces, if that!