LowRider-inspired Foam Ripper

another ex-RCer here…started with RTP and ended with 1/4 scale 50cc. Stopped a couple of years ago as I stopped enjoying the days out at the field. For a foam quickie I can highly recommend one of these made out of 6mm Depron…that will cut well with a needle
thumb-F22-Top

Excellent hi-alpha, dead slow low passes and tail down landings…
Plans available -here

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Ah! A blast from the past! My buddy and I needle-cut, built, flew – and crashed – a bunch of dekan’s F22 foamies… and had a ton of fun doing it. With the needle-cutter, we could cut a new plane, transfer the electrics from the crashed plane to the new, and be back in the air in just a few hours. It also inspired a whole fleet of other planes…

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– David

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This one looks a bit tricky to put together…:slight_smile:

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“You have to listen to the notes she didn’t play”

“Oh man, I could have done that at home”

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Yeah… negative pieces can be handy when doing the CAD but are a bear to assemble. That photo was for all the “hand-cutters” and skeptics out there… there weren’t many needle-cutters in existence then :astonished:

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With the recent interest in Neje’s new dual-diode A40640 laser module, my poor Foam Ripper’s Z-axis has once again undergone more development. I had apparently skipped documenting the move from the last iteration of the little BB-bearing linear slides to a stronger version using threaded rod and Nema17 motor drive…

but I didn’t like the tall profile and occasional coupler issue. So I decided to combine a couple of ideas using the printed leadscrew of the BB-bearing models and Nema17 motor drive.

Shorter yet, without the coupler, and about the same ~75mm travel, I’ve come up with a simpler Z-axis that consists of only 3 printed parts…

The Nema17 motor shaft is fully inserted into a D-shaped recess up the center of the printed leadscrew, effectively creating an intergrated motor/leadscrew and doing away with the coupler. Skate bearings capture both ends of the leadscrew…

There is a touch of slop/sag in the carriage due to using LM8UU linear bearings on 5/16" drill rod but replacing the rails with proper 8mm polished rod should help.

In action, with Neje A40640 ~15W laser cutting 3mm in one pass at 150mm/min and 100% power. Also sports my recently developed printed air-assist…

I’ve published this Z-axis design to Thingiverse, as well as the air-assist parts.

– David

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3D printed Z-axis leadscrew?! We need a mind blown emoji!

That’s pretty awesome! Thanks for sharing!

I was also thinking about getting that dual-diode laser and this has pretty much sealed the deal!

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I was curious about that Neje A40640 laser module someone had mentioned here, so bought one to test and hopefully install on a laser engraver I’d built for my daughter. TBH I wasn’t really expecting much but was shocked to see the vastly improved beam geometry… with line/spot definition on par with my 2.5W lasers but far more power. Daughter agreed and seems very happy now being able to cut much faster and thicker materials for her wooden jewelry. I was impressed enough to order a 2nd one for myself… the one shown cutting 3mm ply above.

:astonished: :smiley:

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You’re convincing me, David. I see the 15W (40W) version on amazon for about $315. I am assuming that is a bloated price for the convenience of 2 day shipping. Where did you get yours?

I bought mine directly from the Neje shop for $259 and free shipping, Jeff. They have a US warehouse and I received both my units within 4 days of order IIRC. Hassle-free and quick… no issues performance or quality. I’m a happy camper! :smiley:

The us shop is out of stock, and it is $239 from China. I am going to pull the trigger. I just need a day or two to think about it.

Bummer. I’m just fearful of ordering anything from China with all the shipping issues right now…

I’ve been ordering odds and ends and I haven’t had any trouble, despite the recent complaints. China is a big place, maybe the problems aren’t evenly distributed? Or maybe the small stuff is easier to get than a container full of hot pants?

You’re in the market for hot pants??? :astonished:

Not anymore. :slight_smile:

I vaguely remember a simpsons episode where a container of hot pants washed up on shore. There was some movie with Robert Redford where he was in a sail boat that was sunken by a container, and I thought that was some kind of shorts too. Somewhere in my brain, I have it in my mind that the container ships often have single containers with nothing but hot pants in them. Somehow, that got through the filter…

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I think the container in “All Is Lost” was sneakers.

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I really appreciate you guys filling me in on where the holes in my “education” are. The Simpsons pretty much came and went without me ever taking much notice. Obviously deprived, I am found sadly lacking…

:wink:

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Or untainted by the silliness.

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Playing a bit with my fun new toy…

Cut a second “heart-tree” (150mm/min at 100% power, ~35 minutes, one pass, air-assist) because the first revealed a bad spot on the 3mm plywood sheet…

Lifted the sheet off the machine and the figure dropped free of the sheet…

Remaining bits fell out easily by themselves… leaving a nice delicate figure intact :astonished:

The first tree has a few bits that didn’t cut through because of the bad spot in the plywood sheet and can’t be removed without breaking fragile limbs…

Still impressed!

– David

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