Anti-Collision_ Will this work?

[RAD]

Hi there, I've been trying to come up with a simple way of preventing torch collisions with 'tip-ups'

So I came up with the attached, it's a conductive plate that surrounds the torch tip, mounted to the torch holder separated by nylon spacers. An electrical wire comes from the conductive plate and one comes from the slats of the table, these two wires goes to the B.O.B as an E-STOP input, therefore as a tip-up makes contact with the conductive plate it closes the circuit an triggers the E-stop.

Will this work? or will I fry my Break-out Board because of the ground of the plasma cutter which is also connected to the slats?

Thanks in advance and apologies if this is a stupid idea

[acourtjester]

well since the ohmic touch uses a similar circuit that should work. but you will need more electronics you could use the Water switch that some are using for a ohmic switch. As long as the tip up metal will conduct with the slat better hookup may be directly on the cut metal plate
https://www.amazon.com/s/ref=nb_sb_noss ... %2FDc+M158

[tnbndr]

You're going to have a wire hooked to the torch plate that zooms around with the torch while cutting?!!! I would think tangling or the wire being cut would be a possibility.
A magnetic break away with a cut off switch would be much simpler.

[RAD]

Thanks guys,

Glad to hear I wont kill my B.O.B by trying this!

@tnbndr
I've drawn it in a simplified way just to illustrate my idea, actually the wire on the torch plate would be routed into the cable carrier with just enough 'slack' to allow for up & down movement of the torch. Also I might replace the nylon spacer with a metal spacer to avoid it melting, I was trying to insulate the torch plate from the torch mount/machine, hence the nylon spacer, this may not be necessary I guess?

one advantage of this over a magnetic breakaway is that the torch tip itself won't absorb any impact with tip ups, although you could make it so that the tip won't feel the impact, that might just add to complexity and I really want to keep it simple.

Another advantage is that the torch plate would shield sparks.

But I'm still open to opinions and ideas if this type of anti-collision still makes sense

[East German]

Hallo
I have a magnet holder with switch. The switch makes the torch off and machine to pause.
At break of zero point remains

Regards Peter

[_Ogre]

not sure how you'd see the torch for alignment and a partial tip up will still impact the torch shield
a mag base will stop damage to the torch from impacts
on thin metal and 250+ ipm feeds i'd think your idea will still crash

best way to avoid tip up impacts is to position your starts/stops where travel can't go over a tipped up part
sometimes traveling over a tip up is unavoidable this is where the mag base comes in handy

[RAD]

Thanks guys,

That makes sense, with crashes somthing has to give and it best be the mag letting loose from its base.
I read somwhere also with some tip ups the torch can actually move it out the way and continue cutting, not the case with my idea

Since my machine isn't up and running yet I have no experience with how often crashes may occur or how bad these crashes can be

Anyway I guess I should be looking for neodymium magnets now, any thoughts on what holding force and how many magnets I should be looking for?

[East German]

My System

Regards Peter

[RAD]

Thanks East German, nice system you got there. Think i'll use two 20mm diameter magnets since i'm using a hand torch and two dowels

[_Ogre]

not sure how dowel pins would break loose in a collision
you want the torch to break away in any x,y,z impact
most mag base break away mounts use ball ends or points that just barely mesh when lining up the torch

[RAD]

I plan on using the balls from a ball bearing and drill holes to match the dia. of the ball, press them halfway into the drilled holes and have semi drilled holes on the breakaway side

[tnjind]

I used button head cap screws on mine, sorry no pics.

[acourtjester]

here is one I made using 3/8" balls and a 3/8" ball end-mill to make the recesses in the other plate.
Did not use a strong enough magnet it worked great but released to easy removed it.
You can buy different size balls at the hardware store.

DSCN2138.JPG