Problem- Torch collisions

[plain ol Bill]

I finally have my table up and running and am having a ball. All the ladies in the neighborhood have the "I want one of those". I have managed to break my Hypertherm T80M torch three times now due to collisions. The first one was new operator error when I told the machine to "go home" in Mach. I did not understand this sends all 3 axis's home so as it was headed for 0,0 the torch hit a slat and it snapped the composite sleeve on the torch. DAMN! I ordered in a part (man they really charge for parts too) and while waiting for it to come I superglued the sleeve back together. Well I have hit tip ups twice now and rebroken the torch.

I REALLY THINK I need to have some sort of anti collision device on my table and want to know what is available or what have you guys done to keep from breaking your torch???? Any help appreciated folks.

[DanOSB]

i have seen some people using strong magnet and another plate machined to fit the magnet tightly (the torch is mounted on the magnet) and when the magnet comes off the limit switch will stop everything else

hope that idea works for you..

[Torchhead]

You need to address the tip ups not build a break-away torch! I have cut for 6 years and have had a few tip ups but the floating head kept it from snapping the tip off. I have my slats setup to be removable and replaceable. There are notches every two inches in the first 2 ff of slats. I can choose to populate or not to make the grid closer or spread it for larger cuts. Tight grid will hold the pieces that are popping up now and anything that does should be short enough to avoid the retracted head. The tighter grid closer to 0,0 allows me to cut small detailed stuff. I still have some things (like internal letters) that will try to popup but I am there with the handly magnet to lift out the drop outs or just poke them back down.

By knowing how the machine is going to cut I know when it's save to walk off and when I better be poised to flick out a piece.

In the CAM (SheetCAM) start looking at it when you build the process list and say to yourself "hey these pieces might just tip up" and using the layer method group those cuts together and stand there with a magnet and gloves on. I can tell just looking at the art work what is a potential problem.

One of the arguments for having the water tray about 4 to 6 inches below the grid is that most pieces will fall on through and not stick up.

Also think about the order that you cut pieces and how high you retract the head. You should not have a layout where the head goes back over a section that is already cut (cut the design either from the center or from left to right. It won't keep close stuff from maybe being a problem but you can have better control. Thinl about how you would cut the piece by hand and set your ctu file up that way. You have immense control of the cut process in SheetCAM. You can also insert code snippets to turn off the torch, raise the read and scoot back out of the way and pause until you hit run again.

Something like:

M05
G00 Z 3.00
G01 X24Y24 F60 (move to X 24 and Y 24 at 60 IPM)
M00

Insert that in SheetCAM between a process in the list to let you go in and clean up loose pieces or between multiple designs.



The big red PANIC button on your controller stops the machine instantly.

Until you learn your machine its best to stay close to the stop button. Never get so impatient you hit a button and "assume" it's going to run full speed and be okay and turn around to do something else. Murphy will get you!

TOM Caudle
www.CandCNC.com

[WSS]

OK, I have not actually built this yet, but have all the parts. I (like Torchead) believe in Mr Murphy. He strikes at the oddest times. I can look him in the eye and still get hit on the nose.

http://cgi.ebay.com/Magswitch-30mm-M...#ht_620wt_1167


http://www.staffordmfg.com/ProductDe...mUrl=Home.aspx


The drawing shows a dual mount, the two can be re-positioned to work together or just in a holding position. I will use two Victor torches cutting at the same time. One will cut straight down and the other will have a BHA-2 attached at 30-45 degrees to bevel the 90 edge. Will it work? I hope so. Hope you can use some of the info.

[Gyrobuilt]

Why not use a collision sensor/ quickstop?
This seems quite cheap for what they are and should save money on torches too........

http://cgi.ebay.com.au/ws/eBayISAPI....m=370222955170

The only problem I can see with the magswitch idea is repositioning the torches accurately after a crash...........

[WSS]

Originally Posted by Gyrobuilt The only problem I can see with the magswitch idea is repositioning the torches accurately after a crash...........

A good THC should handle that with little problem.

[tof1]

Originally Posted by plain ol Bill the torch hit a slat and it snapped the composite sleeve on the torch. DAMN! I ordered in a part (man they really charge for parts too) and while waiting for it to come I superglued the sleeve back together.

How much did they charge for the new sleeve?

[Torchhead]

Okay, I'm gonna go out on a limb here and suffer the scorn of the group.

Please take the following test:

You have just got a new Lexus and don't know a lot about it yet. You get in and back out and ram the neighbors tree across the street and bend up your nice rear bumper. After you get it fixed you:

A: Go cut down the neighbors tree
B: Have a breakaway bumper mounted to the back that is ugly but functional
C: Have pipe welded around the vehicle to prevent any further damage
D: Learn how to drive and not hit trees.


Sometimes the solution is in the mirror

TOM Caudle
www.CandCNC.com

[DanOSB]

Tom,

I had good laugh out of your comment

[plain ol Bill]

Tom I decided to use the rear view mirror approach. I have taken the same file I had the problems with - gone in and manually set the cut sequence and cut start location in Sheetcam (boy - I am really starting to love that program). Admittedly I am a new driver, but it don't take but one wreck and one visit to the body shop for my "Lexus" to learn me to look into that mirror!

tof1 the sleeve was 79 bucks plus second day air service - so it was an expensive lesson. But that is life and ya just gotta keep on keepin on.

Folks I don't know about anyone else, but when Torchead has something to say, I for one, listen closely and pay attention. He has helped me through a confusing (to me anyway) electronics installation on my "Lexus".

[tinman13]

Hi Bill, I don't know if you remember what I have on mine but it has saved my torch many times..........
Plan as you may..... Hover as you might....... It STILL happens!
I use a rapid clearance of 1 1/2", slat space of 4". For the most part it is OK.
You can't always lay out your part for NO tip ups.
Murphy IS lurking!

I like the mag base idea but it adds one more thing to keep clean and to monkey with..... But you may see one on my machine someday!

Glad to hear you are up and running. Have fun, we should get together sometime, I know a few people from out at the plant.....have a couple of stories too
Good luck, Steve

[WSS]

Tom,
Being of the quiz nature, I have thought much about your four choices. Let's break them down:

A: Go cut down the neighbors tree

My first choice, but my chainsaw has a broken pull cord. So....

B: Have a breakaway bumper mounted to the back that is ugly but functional

Actually I would build two, one for the front and since I look in the mirror a lot, one in the front (lexus' accelerate very fast). but since I need a CNC plasma table to help build it I will have to wait on "B".

C: Have pipe welded around the vehicle to prevent any further damage

This is very cool looking but you have to get out of the vehicle like Bo & Luke Duke. And unless you are cruising cow corrals it is not necessary.

D: Learn how to drive and not hit trees.

were do we take the test?


The irony here is in the common sense. Thanks for passing it on!

Tommy