what do you want to tell us ?
Cutting foam sheets... with a needle!
- Thread starter dkj4linux
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Headbang
Master member
Just saying as time has gone there are new ideas, they improve on the designs before them, but they are not simple or easy to implement properly and will take lots of time, trial and error. Pick what works for you. My original one was chosen due to lack of 3d printer. Had no bearings or anything. Still worked well. And don't be discouraged by failure!
you´re absolutely right...finding and solving problems is also the funny part of our hobby...ihave tried many things, but it was an easy solution...of course using a good needle and everything....but a higher quality bearing changed everything. no heat any more...donßt even need to lubricate...
chris398mx
Master member
Is it a flanged bearing? Do you have a part number?
sirjaymz
Member
Awesome to hear !! Glad you were able to get it completed.I finished my CNC machine - Moebeast's Foam Ripper. I have a pen zip-tied to the mount right now, and it draws pretty well. Just gotta get the motor for the needle cutter and I'll be cutting out some planes.First up will be a Tiny Trainer, then a MS P-38.
View attachment 189649
Personally, after having built 3 Tiny Trainers, because I crash often, destroying 1 motor, and countless 6x3 props, teaching myself to fly, I've come to the conclusion that I should have started with the FT Explorer, with the training wing, and several nose setups, as the in-field repairs doesn't take very long to get back into the air. When crashing with the explorer, it doesn't destroy the prop like it does on the TinyTrainer, but I've been destroying only the nose. and the nose slides off easily, and a new one can be installed easy. Quite honestly, I'm still learning the controls, and by using the explorer, I've saved at least a dozen props. I can tell you, the first several attemps, 1 prop lasted 10 seconds on the TinyTrainer. Aggravatingly I built 3 Tiny Trainers, as I don't want to have to perform in-field repairs, and found by using the explorer, I was able to get more 'air time' than the TinyTrainer, and the Explorer quite honestly is easier to fly. Just my $0.02 . I love the whole journey, I just wish I could fly better.. but that will come with time and rebuilds.
2jujube7
Well-known member
I completely agree with that. I was having the same problem with 70% scale FT A-10 (and my original TT), until I installed landing gear. It really absorbs the shock of landing and I've saved many props with the addition of gear.Awesome to hear !! Glad you were able to get it completed.
Personally, after having built 3 Tiny Trainers, because I crash often, destroying 1 motor, and countless 6x3 props, teaching myself to fly, I've come to the conclusion that I should have started with the FT Explorer, with the training wing, and several nose setups, as the in-field repairs doesn't take very long to get back into the air. When crashing with the explorer, it doesn't destroy the prop like it does on the TinyTrainer, but I've been destroying only the nose. and the nose slides off easily, and a new one can be installed easy. Quite honestly, I'm still learning the controls, and by using the explorer, I've saved at least a dozen props. I can tell you, the first several attemps, 1 prop lasted 10 seconds on the TinyTrainer. Aggravatingly I built 3 Tiny Trainers, as I don't want to have to perform in-field repairs, and found by using the explorer, I was able to get more 'air time' than the TinyTrainer, and the Explorer quite honestly is easier to fly. Just my $0.02 . I love the whole journey, I just wish I could fly better.. but that will come with time and rebuilds.
Headbang
Master member
And with a good concept and needle cutter you get to cut them in bulk. Lost count how many explirers I have cut for ppl.Awesome to hear !! Glad you were able to get it completed.
Personally, after having built 3 Tiny Trainers, because I crash often, destroying 1 motor, and countless 6x3 props, teaching myself to fly, I've come to the conclusion that I should have started with the FT Explorer, with the training wing, and several nose setups, as the in-field repairs doesn't take very long to get back into the air. When crashing with the explorer, it doesn't destroy the prop like it does on the TinyTrainer, but I've been destroying only the nose. and the nose slides off easily, and a new one can be installed easy. Quite honestly, I'm still learning the controls, and by using the explorer, I've saved at least a dozen props. I can tell you, the first several attemps, 1 prop lasted 10 seconds on the TinyTrainer. Aggravatingly I built 3 Tiny Trainers, as I don't want to have to perform in-field repairs, and found by using the explorer, I was able to get more 'air time' than the TinyTrainer, and the Explorer quite honestly is easier to fly. Just my $0.02 . I love the whole journey, I just wish I could fly better.. but that will come with time and rebuilds.
2jujube7
Well-known member
Tonight I finished the needle cutter part of my Foam Ripper, and I was able to cut out a few basic shapes that I found online in the .dxf format. Next, I tried to convert the TT plans to be .dxf using Inkscape, but it isn't quite working out. I know what I have to do, but the drawing just doesn't seem to be cooperating. Parts of it will randomly white out and just not exist anymore. (Without me deleting anything ) Here's a screenshot of the closest I've gotten. Has anyone had this problem before? Am I just doing something wrong?
) Here's a screenshot of the closest I've gotten. Has anyone had this problem before? Am I just doing something wrong?
Wildthing
Legendary member
I have no idea having never done it but I would try increasing the thickness of the lines before converting them and see what happens.Tonight I finished the needle cutter part of my Foam Ripper, and I was able to cut out a few basic shapes that I found online in the .dxf format. Next, I tried to convert the TT plans to be .dxf using Inkscape, but it isn't quite working out. I know what I have to do, but the drawing just doesn't seem to be cooperating. Parts of it will randomly white out and just not exist anymore. (Without me deleting anything
View attachment 189920
2jujube7
Well-known member
Alright, I figured it out. I had to place it on the 20x30 page the first time and not move any parts around. Now I'm stuck on another part: saving. It gives me this message when I try to save the dxf. I was able to save an svg, but still not a dxf. I tried different directories, to no avail. I have no idea why it's saying this, and I've tried lots of things. Sorry for bringing my noobie questions to the forum.
Headbang
Master member
Inkscape can be a bit evil on some computers, good chance the info is still there, just not being displayed. Zooming in and out can help, saving in svg and reopening can help. Ungrouping helps sometimes, but ungrouping can sometimes feel like things are locked up, wait it out.Tonight I finished the needle cutter part of my Foam Ripper, and I was able to cut out a few basic shapes that I found online in the .dxf format. Next, I tried to convert the TT plans to be .dxf using Inkscape, but it isn't quite working out. I know what I have to do, but the drawing just doesn't seem to be cooperating. Parts of it will randomly white out and just not exist anymore. (Without me deleting anything
View attachment 189920
Headbang
Master member
May need to ungroup, be sure no graphics are left, just vector drawings. May be the settings when you are saving it. Also try the other dxf format that you have an option of.Alright, I figured it out. I had to place it on the 20x30 page the first time and not move any parts around. Now I'm stuck on another part: saving. It gives me this message when I try to save the dxf. I was able to save an svg, but still not a dxf. I tried different directories, to no avail. I have no idea why it's saying this, and I've tried lots of things. Sorry for bringing my noobie questions to the forum.
View attachment 189932
CartCurt
Member
What operating system are you using? I use Windows and have found that I have had issues with dxf files in Inscape 1.0.x. I now only use Inscape 0.92.x and have no issues saving dxf files. They import with the correct scale when I create gcode.Alright, I figured it out. I had to place it on the 20x30 page the first time and not move any parts around. Now I'm stuck on another part: saving. It gives me this message when I try to save the dxf. I was able to save an svg, but still not a dxf. I tried different directories, to no avail. I have no idea why it's saying this, and I've tried lots of things. Sorry for bringing my noobie questions to the forum.
2jujube7
Well-known member
Yeah, I use windows also. I'll try 0.92.x, thanks!
Download Doublecad.Alright, I figured it out. I had to place it on the 20x30 page the first time and not move any parts around. Now I'm stuck on another part: saving. It gives me this message when I try to save the dxf. I was able to save an svg, but still not a dxf. I tried different directories, to no avail. I have no idea why it's saying this, and I've tried lots of things. Sorry for bringing my noobie questions to the forum.
View attachment 189932
In InkScape, save the svg file.
Open DoubleCad and open the svg., save as a DXF.
Save the file with the name that doublecad assigns. Usually, FILENAMEuntitled. In file explorer you can change the name to whatever you want.
So I have my mpcnc working great. Vacuum table made with it and the dealt works great. I really want this cut foam board for FT planes to use for STEM and intro to flying. The machine makes great cuts but like most, the needle breaks between the bearings and the motor. So a couple of questions. Which cutter head are people having the most success with? What are people using to measure the rpms? Here is a video of the system running. This is before the vacuum table was up and running.
2jujube7
Well-known member
I know this probably isn't the best method to test the rpms, but I just set the speed of the motor to 20% (using throttle hold on my tx) and I was able to get a good cut at 20mm/s. (using a 3s battery) Any more rpms than that, and the needle starts bending because of the centrifugal force acting on it between the flywheel and MIG welding tip. I'd recommend either buying an optical tach from somewhere, or just trying my strategy and going slow.
Oh, and I'm using a stock flywheel that Moebeast has on his Foamripper's Thingiverse page.Thank you. I just bought a Tach. That should help. I am using a power supply and a servo tester to set the motor speed. There is a good chance I was going way too fast. ThanksI know this probably isn't the best method to test the rpms, but I just set the speed of the motor to 20% (using throttle hold on my tx) and I was able to get a good cut at 20mm/s. (using a 3s battery) Any more rpms than that, and the needle starts bending because of the centrifugal force acting on it between the flywheel and MIG welding tip. I'd recommend either buying an optical tach from somewhere, or just trying my strategy and going slow.
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