Hand held needle saw

[behnt]

I am working on developing a needle saw (basically a tattoo machine). Here is a quick video of my prototype.
Any suggestions or comments?

Ben

 

[dkj4linux]

I am working on developing a needle saw (basically a tattoo machine). Here is a quick video of my prototype.
Any suggestions or comments?

Ben

Excellent, Ben! Those cuts look nice and clean. From what I can see, it looks like a "conventional" prison tatoo gun with a larger stroke... do you have plans to share your design? I for one would love to see it... and I should think this very interesting to those "CNC-challenged" among us

-- David

 

[behnt]

The cuts are pretty clean. Yes it is a conventional or rotary tattoo gun with a 6mm stroke on one and a 4mm stroke on the other. I will be doing a full build of the machine soon and I will record it. I am also working on a nice 3D printed version. All plans from me will be free.

I owe you a debt of gratitude for your posts here David. They set off a storm of ideas in my head for things like this. So thank you!

I built it because I am currently CNC challenged. I am building a CNC platform shortly but work and family are extending the time to build it further than I had expected. This took me a couple hours to build and I was cutting out my robot platforms that are inspired by the FliteTest foam core planes with it.

 

[dkj4linux]

The cuts are pretty clean. Yes it is a conventional or rotary tattoo gun with a 6mm stroke on one and a 4mm stroke on the other. I will be doing a full build of the machine soon and I will record it. I am also working on a nice 3D printed version. All plans from me will be free.

I owe you a debt of gratitude for your posts here David. They set off a storm of ideas in my head for things like this. So thank you!

I built it because I am currently CNC challenged. I am building a CNC platform shortly but work and family are extending the time to build it further than I had expected. This took me a couple hours to build and I was cutting out my robot platforms that are inspired by the FliteTest foam core planes with it.

Thanks, Ben. Glad I could help in some way

This really looks good. There's been talk of developing a hand-held needle cutter in a couple on my threads but, to my knowledge, you are the first to demo a practical unit. I've looked at the prison tatoo guns before of course but never really thought, in a light-weight unit, they'd have the power to pierce/cut DTFB... kind of a "worst case" foam, with the paper on both sides. Yours seems to do so very cleanly and quickly... that's some serious power and RPMs you have there. I'm really looking forward to seeing how you selected components and put it all together.

Good work! -- David

 

[behnt]

Thanks, Ben. Glad I could help in some way

This really looks good. There's been talk of developing a hand-held needle cutter in a couple on my threads but, to my knowledge, you are the first to demo a practical unit. I've looked at the prison tatoo guns before of course but never really thought, in a light-weight unit, they'd have the power to pierce/cut DTFB... kind of a "worst case" foam, with the paper on both sides. Yours seems to do so very cleanly and quickly... that's some serious power and RPMs you have there. I'm really looking forward to seeing how you selected components and put it all together.

Good work! -- David

No serious power there. It is only a 5v motor I got from a toy gear box and very little amp draw. I am thinking maybe 250mA. You would be surprised how little force is needed with such a small diameter wire. Also making sure it is sharp makes a difference in cut quality. But I am sure you already know that.

 

[Balu]

I love the design. Would've never thought about a tattoo-gun like machine, more like a saber saw. Great idea.

 

[pakrat1022]

I would be very interested in how you built that

 

[TheSFReader]

Any indication of what "downward pressure" is needed to obtain a correct cut with a needle cutter on DTFB ? Wondering if "laser engraver" like architecture wouldn't be sufficient for that use case (as opposed to full CNC)

 

[CMS_1961]

Awesome idea!!! Started converting a CNC machine to cut with a needle, but this is quicker for small cuts and one off planes!!!

 

[dkj4linux]

Any indication of what "downward pressure" is needed to obtain a correct cut with a needle cutter on DTFB ? Wondering if "laser engraver" like architecture wouldn't be sufficient for that use case (as opposed to full CNC)

If I understand your question about using the needle cutter on a "laser engraver"... if you do not have a Z-axis implemented that will lift the cutter out of the material, then you will have to have some way to stop the cutter's rotation at the top of stroke, when the needle is clear of the material being cut, to move to the next cut. I'm not yet sure of how Ben's cutter is constructed but it does appear to me that every time he sets the cutter down on the table the needle may be fully retracted... so he may already have addressed that problem for you. -- David

 

[RCman50]

That is sweet. Have you tried any freehand with it, say on a round shaped rudder? Or strictly straight line cuts.

 

[behnt]

I would be very interested in how you built that

I will be doing a build video soon. But google 'jail tattoo machine' 'or 'diy tattoo gun' or derivatives of those and the videos will be enough to get you started. I am working on a 3d printed version too.

 

[behnt]

Any indication of what "downward pressure" is needed to obtain a correct cut with a needle cutter on DTFB ? Wondering if "laser engraver" like architecture wouldn't be sufficient for that use case (as opposed to full CNC)

Hardly any pressure is needed. the weight of the pen is enough

 

[behnt]

That is sweet. Have you tried any freehand with it, say on a round shaped rudder? Or strictly straight line cuts.

Yes and it will take some practice but a drafters circle template is your friend here for clean curves. It will take practice for the small detail stuff but I am positive it is doable as tattoo artists can...

 

[TheSFReader]

If I understand your question about using the needle cutter on a "laser engraver"... if you do not have a Z-axis implemented that will lift the cutter out of the material, then you will have to have some way to stop the cutter's rotation at the top of stroke, when the needle is clear of the material being cut, to move to the next cut. I'm not yet sure of how Ben's cutter is constructed but it does appear to me that every time he sets the cutter down on the table the needle may be fully retracted... so he may already have addressed that problem for you. -- David

Actually, the question was not about lifting/lowering the z-axis, but how "strong/rigid" the 3 axes actuators need to be to control the needle saw. I supposed that the forces were low enough to use lightweight 3 axes rails/motors rather than full strength ones.

 

[dkj4linux]

Actually, the question was not about lifting/lowering the z-axis, but how "strong/rigid" the 3 axes actuators need to be to control the needle saw. I supposed that the forces were low enough to use lightweight 3 axes rails/motors rather than full strength ones.

Sorry... I misunderstood. Yes, the tool forces when using the needle cutter are quite low.

 

[behnt]

UPDATE:

Here is a 3D printable version. This is version one so still improvements need to be made.

Needed are:

• 1mm I.D. brass tube
• Motor
• Old USB cable
• Switch
• USB wall wart

The skinny. Cut the usb cable to power the motor and solder it in (add inline switch if you want one, I recommend it and will design version two with a finger switch)
Glue in the brass tube, glue halves together, assemble as per using small tie wraps. Make needle out of guitar string 0.017 size or larger. adjust height of motor. CUT!
https://cad.onshape.com/documents/8...8a2f709a8f488990ff/e/f397fd311f610b3bd4dd57d1

I know the directions are seriously lacking but there is enough there for the DIY person to make one. Let me know how it goes.

 

[dkj4linux]

Very nice, Ben. I've been anxious to hear more about your hand-held cutter. Are you, by chance, planning to release the STL files for those of us who are OnShape-challenged? -- David

 

[behnt]

Very nice, Ben. I've been anxious to hear more about your hand-held cutter. Are you, by chance, planning to release the STL files for those of us who are OnShape-challenged? -- David

Of course! You should be able to right click the stl tabs at the bottom of the Onshape document to download. If not I'll correct that in the morning.

 

[dkj4linux]

Of course! You should be able to right click the stl tabs at the bottom of the Onshape document to download. If not I'll correct that in the morning.

I get is a message that says "This document was shared via a link and is view only." -- David