Good afternoon Gents, I would like to avail myself of your collective wisdom, if i may. I am running a 45 sync with a 45A standard cartridge and getting a lot more bevel in the cuts than I would like.
Am using the “book” settings for cut , pierce height and the pierce delay i upped by .5 as seems to be everybodys recomendation. Am cutting 1/8 MS so am using the 10ga settings.
The “book” feed rate is 95ipm and I have been using this to get started. Remembering the suggestion to drop feed rate +/- 20% over a water table i am now trying this.
When i reduced the feed rate thru Firecontrols overide option 20% it threw an error saying “torch moved before voltage sensed” and suggested i increase the pierce delay.
So i’m wondering if this makes sense to anyone? I am already at an elevated pierce delay and the very same programme runs just fine at the “orriginal” feed rate.
Does dropping the feed rate require the pierce delay to be increased too? When I took the override off, it ran just fine again.
Thinking the override feature might be wonky, I put the drawing back into Sheetcam and re set the feed rate to 75ipm and tried again. Same error comes up. So having nothing to loose, I upped the pierce delay by 10% thru firecontrol and it ran fine this time. Again, does this make sense to anybody?
Sure would appreciate any insight you can share.
A good assumption is the cutting height and speeds need adjusted to match your setup.
First off have you confirmed that you are definitely cutting at the correct programmed height? Several people has had to adjust it. Incorrect cut height can cause a bad taper. Second I would slow down some more. I would rather have the slag or dross than a bad bevel. I made some changes to my setup once and really had to downshift on 1/2 material. I will see if I can locate the thread I made about it.
To your question changing cutting speed should not require you to change your delay.
Thanks for the reply. The sync uses real high cut heights. I head scratched over this quite a bit and dropped the cut height by half and found no difference. I am back to using book heights and am now trying speeds. Book speed is 95ipm, and as i mentioned before i dropped it to 75, then 60 but with no real difference in bevel.
what was really puzzeling me was the weird way Firecontrol was behaving, throwing errors untill i changed something that, i thought, didn’t make sense to change.
Doesn’t seem to matter what i try i can’t reduce the bevel. I’ll try even slower tomorrow but I am not holding my breath.
What Phillip means is, did you confirm your physical cutting height matches that of what you are inputting.
Just because you type into your CAM programming a value of say “0.12” does not mean it is physically cutting at 0.12”.
When I used to run a Langmuir table, my plasma cutter called for a physical cut height of .063” however the only way I could achieve this was with a programmed cut height of .02”.
You have not shared what you are physically cutting at.
Also, 1/8” (0.125”) is thinner than 10 gauge, so normally you would run faster than the book setting of 95ipm. Use that as your base, then create test cuts.
Have you physically measured your cut height though?
Run this program it will not fire the torch. When the program ends measure the gap between the material and torch. Your actual cut height could be off from what fire control says it is.
cut height test.tap (224 Bytes)
Hypertherm is really close on their settings but sometimes you just need to fine tune .
There is a possibility you could have a bad or damaged cartridge. Have you tried a new one? Post a picture of the cartridge looking into the nozzle part. Is the hole round?
To cut 1/8 material you should be cutting faster than 10 gauge settings. The cut chart I saw had 12 and 10 gauge I would split it the reduce 20%. What voltage are you seeing? Have you tried nominal?
1/8” = 11 ga
Remember overriding settings in fire control only last till you done cutting then it goes back to what it was. Its easy to get messed up changing settings this way.
Thanks guys; you are right, I have not yet measured my actual cut height. I wondered about the high cut height for the sync and a few people responded that i should stick to the book settings.
Previous to this I changed settings from .125 down to .06 and saw no difference in bevel. So even though i haven’t actually measured anything yet, I have tried a number of heights.
I will try even slower later to see what happens, but the real poser was why Firecontrol needed a longer pierce delay at a reduced feed rate to fire the torch?
This is what really has me baffled.
Don’t over complicate things.
It sounds like you are just trying to stick to the book, as if it’s a hard fact.
Do yourself a favor and make a small test cut piece. Cut several pieces out at different feed rates, and determine multiple values such as -
Physical cut height
Kerf value
Speed
And what you’re looking to achieve is a square edge (minimal bevel) cut correctly to size.
This requires very little effort on your end to actually do, but you need to actually do it which you’re not. As for pierce delay and feedrates, I’ve used 3 different computers, 2 different tables, 2 different plasma cutters, and 3 different torches, and found that pierce delay did not at all correlate with feedrates. You may be overriding more than one item when you enable the option as you’ll see multiple boxes with different values.
I appreciate your patience wit me. The test piece i am cutting is a square, a circle, and a triangle, all inside a 5" square. I thought this would give me a good variety of geometry to look at.
I have cut 6 or so if them at different feed rates and so far have not seen any appreciable difference in bevel. The bevel is all the way around each shape, both on the inside and outside cuts; all beveling outward from top to bottom. It is as if it is cutting more on the top than the bottom.
Since you obviously have way more experience than I, could the height of the water be cooling the bottom too fast to prevent full penetration? I have it full to the top.
As for your other thoughts, please re-read my orriginal post to refresh your memory on what has been going on.
Thanks.
Both cut height and speed would attribute to this “equal but beveled” edge all the way around. On the plus side, being that it’s equal means it isn’t a sign of a bad consumable or a z-axis assembly that requires tramming.
Being a Hypertherm makes it easier because you won’t have to mess with air pressure at all since it’s automatically done.
Pictures of your “test cuts” depicting the cut height (physical) and feedrate cut at would help much more than words.
I checked the tramming this morning, it is as bang on as these old eyes can tell. Two of the bottom bearings were running free so i squeeked them in a bit to just touching. I also put a felt pen mark on the cartridge and unscrewed it , hole looks round to me. When i put it back i got the pen mark about 30 degrees from where it was so this might tell something later.
I’ll try for some pics tomorrow,
Thanks for hanging in there.
Are you cutting the right direction?
Outside cuts should be clockwise and inside cuts should be counterclockwise.
Pretty sure, I am using outside offset and also reverse direction in sheetcam.
What started all this was the strange responses i was getting from firecontrol not firing the torch untill i increased the pierce delay. Ever heard of this before?
You are cutting the correct direction, if you have “reverse cut direction” selected in Sheetcam.
I have not heard of feed rate changes requiring a different delay. It would be nice to know exactly what delay you are using, instead of .5 more than book. Most of us don’t know what that book setting is.
I run 1/8” at 45 amps, 95 IPM with a .5 second pierce delay.
What is your plunge rate setting in Sheetcam? The default is just over 3 IPM and I run it at 70 IPM.
Maybe you could post the G-code that you are using and one of us could see if there is an obvious problem.
I have been using Hypertherms 810500MU Rev.4 manual as a starting point.It gives recomendations for all the parameters for the Sync machines (I have the 45 ). The pierce delay they want is 0.4 sec. for 10ga. I recall that everyone here says to add 0.5 sec. to these numbers due to the way Hypertherm measures things. So I have been using these Hyp. settings but increased by 0.5 sec.
So my PD on this material is 0.9 sec. The plunge rate I set all of them to 60 IPM, and the feed rate is 95 IPM.
It was when I changed the feed rate to reduce the bevel in the cuts that all the fun and games began, as i related in my orriginal post. It kept happening untill I upped the PD by 10% thru firecontrols override feature, then ran fine.
This is what prompted my orriginal query to the forum, not so much the bevel issue, although that would be nice to solve too.
test 3 (10ga std).tap (1.9 KB)
.9 seconds should be too long for 1/8” steel.
A delay that is too long is just as bad as one that is too short. The torch can burn away the metal needed to maintain the electrical connection and flame out before it gets a chance to move.
Yeah, 0.9 seconds is way too long especially for 10 gauge. I ran 0.5 even for 3/16” with my Hypertherm.
Being that 0.5 seconds has been suggested, and acknowledged, why not keep it at 0.5?
I would also just post process 4-5 files each at different speeds for your test cuts instead of running so many overrides. You could be overriding more than one item when you’re changing things.
It is very likely i missunderstood what everyone was referring to regarding this .5 sec. bump up. I thought the suggestion was to simply bump all the hyp. pierce delay recomendations up by .5 sec. Some of thicknesses show 0 for a pierce delay. So i started at .5 and simply added this to all their numbers.
Are you suggesting going with their numbers (for starters) but don’t go less than .5? In other words, go with .5 untill it coincides with hyps then use their numbers after that?
Not wanting to throw a wrench into the machinery, why do you think then Firecontrol needed me to increase the PD (above the .9 i was using!) when I reduced the cut speed?
No one is referencing Hypertherm’s book at all. This is something you keep adding to conversation.
Use 0.5 pierce delay for everything, and you will be good to go. Do not use less than 0.5, and if you use more than 0.5, it shouldn’t be by much. But no one has referenced Hypertherm’s book.
I am just getting started in all this so I have been using Hyps numbers as a base line. Everybody on this forum ( perhaps not you), seems to consider Hypertherm as the gold standard, and that is why i am starting with their recomendations for the variables. It has been abundantly confirmed that Firecontrol and Hypertherm’s PD times differ by 1/2 second and it also has been confirmed adding 1/2 sec accounts for this.
It only makes sense to me that if something is out by a certain amount, this will be the case across the board. This is assuming of course that PD is a linear relationship. If it is exponential, where the further one goes, the less the difference is, then that sheds a whole new light on the subject, and your suggestions begin to make more sense.
I will try it and see what happens.
Thankyou.