NEJE Diode laser success with Hobby Lobby FB

After a good bit of experimenting, I finally had success with my diode laser and Hobby Lobby black foam board (black paper and a black core). My laser is the large Neje 3 Max with the A40640 laser head. I clean up the plans with Inkscape and burn with Lightburn software. The lightburn auto detects the different colors and sets up a different cut for each color. For a full cut I go 3 passes, 100% power, at 6000mm/min speed. For a score cut I go 2 passes at 70% power, same speed. For a shallow score (like a blue line on a wing) I go 1 pass at 50% power, same speed. If I just want to cut the paper (like for peeling it) I go 1 pass at 25% power, same speed. Finally, if I just want to leave a reference mark on the paper without cutting it I go 1 pass at 15% power, same speed. By keeping the speed real high, it prevents the laser from lingering and reduces melting. It only takes a couple minutes for a full sheet. All cuts are with air assist.
Cost: the hobby lobby foam is $2.99 per sheet but it is worth the cost for the convenience.
Weight: it is a little heavier. I weighed 5 sheets each of Hobby Lobby black, Dollar Tree black with white core, and regular DTFB. The DT black weighed 103.4 grams. The regular DTFB weighed 112 grams. The Hobby Lobby black weighed 158.2 grams. I made up some of the weight by adding holes to internal sheets such as wing spars and doublers (see pictures).
Strength: this HL foam seems a little stronger. The paper adhesive seems a little stronger as well. It also takes spray paint as long as you go multiple thin coats. See the picture of the canopy that I painted. Blue painters tape sealed well and was easy to peel off.
For my first plane I tried Airc-Pirate's 50mm EDF Goshawk. Overall it turned out pretty good. I call it the "Bat Jet" I will have to wait till spring for the maiden.
Here are quite a few pics.
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Old and rusty

New member
Wow, took a quick spin around the Internet today looking at foam board to see some of the other brands available...the vast variety, as well as the price differences were somewhat staggering. So far I've only used the Dollar Tree Adams foam board (white), but lately have been wondering if some brands were superior to others. Went from the Adams DTFB all the way to the 16.00 (on sale) per sheet Gatorboard, (which, hands down looked the best to me) and pretty much everything else in between. At one time had thought the different brands were all actually the same just carrying different labels...but couldn't have been more wrong about that.
I think I'll go middle of the road price wise next time and check out some of the Hobby Lobby black foam board at 2.99 per sheet and see how that goes.
 

Mr NCT

Site Moderator
Wow, took a quick spin around the Internet today looking at foam board to see some of the other brands available...the vast variety, as well as the price differences were somewhat staggering. So far I've only used the Dollar Tree Adams foam board (white), but lately have been wondering if some brands were superior to others. Went from the Adams DTFB all the way to the 16.00 (on sale) per sheet Gatorboard, (which, hands down looked the best to me) and pretty much everything else in between. At one time had thought the different brands were all actually the same just carrying different labels...but couldn't have been more wrong about that.
I think I'll go middle of the road price wise next time and check out some of the Hobby Lobby black foam board at 2.99 per sheet and see how that goes.
I used the Hobby Lobby board on my first simple cub because you can get different colors. I didn't realize a the time the weight difference, the Hobby Lobby is almost twice as heavy per sheet. It didn't increase the overall weight by double but it did make it tail heavy.

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Old and rusty

New member
I used the Hobby Lobby board on my first simple cub because you can get different colors. I didn't realize a the time the weight difference, the Hobby Lobby is almost twice as heavy per sheet. It didn't increase the overall weight by double but it did make it tail heavy.

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Like the idea of different colors...guess it would depend on the type of paint, but do you think the plane constructed of the HL heavier foam board would weigh more than a fully painted plane made with the Adams foam board? Did you use clear tape over the colored covering? Is the HL foam board much sturdier...I appreciate the info.
...the cub looks great, by the way
...
 

Mr NCT

Site Moderator
Yes, the HL board plane was heavier than the DT painted plane.
Didn't use clear tape on the HL, somewhat sturdier.
The simple Cub is prone to tip stalls if you don't keep your speed up in turns and my first two (second was DT painted) died in dramatic manor this way. I skinned my third one with printed paper skins and finally learned to fly it.