What can laser cutting really do ?

[jim gilmore]

I am not sure if thyere is a best place to post this.
First off I'm returning to building aircraft and hope to be flying one this summer. The shark 402 is a laser cut kit but I'm curious of what limitations laser cutting has. I adim to being rough when I move stuff around and have split a few ribs that bwere already glued in. The question I have has to do with the fact that some of those splits happened right inline with the lettering burned into the ribs. 1 even followed the "w" leaving little matching points to glue it back.
   Would it be better to not burn the markings into the wood and have a template to hand mark the parts ?
Does this happen to all laser cut parts or is it a rairety ?

[Scott B. Riese]

Any time you burn wood the wood becomes brittle. Handling Lazar cut ribs is like walking your BULL in a china shop. This is what I do. Ribs are lay ed out and then I sand the burn or scores off with 220. Go light. I still think most of the Lazar cutter out there are taking just a bit to much out of the ribs as to lighten them up. JUST MY OPPION. Handle them as little as you can. AND have plenty of CA to fix what your fat fingers mess up.....It's all  part of modeling 

[phil c]

the marking on the wood should not really be burned much at all.  There is no reason to.  You can get a nice mark with about 1% of the power it takes to cut the wood.  The biggest problem I've had is that wood, being a natural material, varies quite a bit.  It is not uncommon at all to have spots in a piece that are twice as hard and don't burn all the way through.

[jim gilmore]

Sorry I didn'tmean it as a complaint. I was wondering if it was common . Yes the cut parts are great. Does it also do circles well.Sometimes I do not always write all that I mean to. I'm hoping it can cut clean .200 diameter circles but I do not know .

[john e. holliday]

Not only does the Laser dry out the wood a little more.  It will do what you program it to do time after time unless you change the program.  That is why some make a run and then build to see if the program need tweeking.  Once the program is correct and on a disc the kit can be reproduced numerous times.  As I stated earlier a laser will do exactly what the programmer tells its to do.  Having fun,  DOC Holliday

[tom hampshire]

    Laser cutting is a generational leap in kit production.  First, it eliminates the risk to an operator placing and pulling  stock in a running punch press.  Not for nothing are there multiple redundant safety interlocks on those machines. 
    Second, per Ty's comment, the accuracy is much much better.  I have a basement full of carefully collected 50's and 60's kits that I'll never build, simply because far a few bucks I can now get laser cut of anything I want.
    Third, and most important, laser cutting has totally changed the economics of the kit business.  With die cutting, it only made sense to cut a run of kits unless a minimum 500 could be made, to amortize the tooling and setup cost.  The run size drives the inventory cost, and requires a big warehouse to hold the unsold kits until demand catches up.  With lasers, once the program is written, runs as short as 5 or 10 kits can be made and shipped quickly.  The inventory and warehouse cost goes way down.  It seems to me that this is the reason for us having so many OTS and classic kits available.  It can't be because our numbers have increased by any great amount.  It can only be because the cost of having a laser program stored on disc is so small.  Tom H.

[Pinecone]

Heck, if you have the laser setup, you can cut each kit to order.

Laser cutting is just like CNC routing or milling, just using a laser as the cutting tool. Pretty much the same capabilities and accuracy.  Lasers make less dust when cutting wood.

[Dick Fowler]

One thing I've noticed with laser cut parts is that the good kit guys use lighter grades of balsa when compared to die kits. I would imagine that die cutting would just crushed these softer, lighter grades. So you get a lighter product... but it's bit more fragile. Won't tell you how many ribs I cracked building the RSM Humongous wing!

[jim gilmore]

Nice to know this isn't  limited to just me.

[Pinecone]

The other advantage of laser cutting is teh small "tool" size.  Some of the designed from scratch for laser cutting have interlocking tabs that make building almost too easy.

Check out some of Steven Aero kits for some AMAZING design.  You can literally build the entire airframe without glue, then just hit teh joints with CA.  And I mean you can assemble and pick up the major assemblies without glue.

[David Shad]

There is no doubt in my mind Jim you are NOT the only one that cracks a few parts....after building more than a few Laser cut kits in the last couple of years I am not breaking near as many parts now as I did when I came back to control line planes...but I do still crack a few...and the CA bottle is always close.

What can a Laser cutter do?  Straighter lines...perfect circles and can cut a kit in a tenth the time I can do
it even with ready to go templates.  It doesn't get eyestrain or sore butt either after sitting in the same spot
for an entire evening.  Definitely works for me!!!