Hello all, its been a while since I have been here regularly, I am sorry.
as some of you know, in addition to being a fan of building things like CNCs, I also make chefs knives. has anyone attached a pneumatic dot peen system to a MPCNC? I did search the forum…
thanks
Ben
I have read pretty much every post and I have not seen that. It is really interesting.
One potential problem is that some of the mechanical choices are based on the idea that the Z forces will be mostly downward. Because the weight of the router is great. You may need to install a (gasp) anti backlash nut on the Z. Or maybe just find a way to clamp the Z and add some weight at a fixed height.
What kind of mechanism does the action? Is it pneumatic?
You could try one of these instead. It is electric and lightweight with variable speed and linear throw (as opposed to rotary cutting). I assume you could probably do that remotely like what can be done with the routers. Plus with replaceable tips you could do whatever profile you could grind into one.
I have one for marking tools and have also considered it as an attachment to the machine I’m building to draw out bend lines, or mark drill points, etc. I will say that it is obnoxiously loud for how small it is though.
Have you looked into an air scribe? Or is that what you’re talking about? I haven’t seen it on a v1 machine yet but they are on diy cncs.
I think that’s exactly what I am talking about. I didn’t know that name. thank you. I will dig into it more.
thank you, for $25, I don’t mind trying it to see how it works. great idea
Happy to help. I hope it works out for you!
I know it doesn’t have control of each individual stroke of the tool, just an on and off, but I think it could work.
I’ll look forward to seeing it in action!
A new attachment…I am waiting. Did you get to the hardware store yet? 
I am very interested!
I should make it to the store later today. I may try my initial tests with a pen mount. Or a modified drag knife mount I made that attaches to both size of the z mount with 4 screw
I have the dremel. Covid shot #2 is starting to wear me down. Hopefully I can get to try this tomorrow.
Take it easy, the projects and R&D can wait!
Mine is tomorrow had covid in December so I’m hopeful I don’t get it again once was bad enough this helps keep my mind clear
I hacked together my 1st attempt. I know this crowd would be more interested than anyone else.
I use the pen holder and a rigified drag knife holder I hacked together from Ryan’s design.
I think I can clean this up a little by fixing the mounting and tweak the file as far as where the z touches down or drags. This is about 18 mm x 18 mm.
Not bad for a first attempt. To me it looks like it might just be too close, or less pressure.
I think you are right. I think the next attempt will probably start with a modified version of your pen holder. something taller, still rigid in the x,y plane, but some wiggle room in the Z
This is awesome! I’m glad it worked!
Check out this Add-on Pen Holder for inspiration - it includes a contact so it can also serve as a Z zero probe.
Cool!
a bit of a zombie here, but this is (surprisingly) the ONLY thread I can find on dot-peening. Which is a little surprising to me as it makes awesome, durable markings in just about anything - much more scratch or tamper resistant than laser or rotary-etching.
I have the dremel tool mentioned - in hand it is an absolute bear to make finely detailed letters because the side to side (radial) play of the tip is significant. I have a lowrider v3, but actually only came here after I couldn’t find anything resembling an “industrial” version in stylus / handheld format. They all are mini cnc machines … which I already have if I’d just finish the build! 
@bense if you’re still around -
One mechanical driven, spindle mount version is DuraDot CNC Marking Tool | Marking Machines. I actually think I"d prefer pneumatic for it’s simplicity, but really just want something that can hold the tip closer to the axis / have less play. The common import machines seem to use a brass bushing, such as https://www.aliexpress.us/item/3256807726001349.html ($30 for the head - i haven’t been able to find a picture of how the portable pneumatic implement the retraction.
