circle issues

Cut quality issues can be discussed here, most common issues have been discussed here and should help you.
Post Reply
mcmental
2.5 Star Member
2.5 Star Member
Posts: 136
Joined: Thu May 14, 2020 10:06 am

circle issues

Post by mcmental »

morning all, just had a quick go at cutting a circle template out for my brother and well the circles aint really circular so im guessing i have settings wrong?
hypertherm 45xp using finecut consumables and settings from the book, 1.5mm stainless steel.
to stop the burn through do i need to make my lead in's longer?
stainless 1.5mm.jpg
adbuch
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 10138
Joined: Thu Sep 21, 2017 5:22 pm
Location: Tucson, Arizona
Contact:

Re: circle issues

Post by adbuch »

What kind of table are you using, and what software for your cam? Sheetcam or? What do the drop outs look like?
David
robertspark
4.5 Star Elite Contributing Member
4.5 Star Elite Contributing Member
Posts: 1832
Joined: Mon Jun 12, 2017 6:43 pm

Re: circle issues

Post by robertspark »

if using sheetcam, set to pierce at the center of the hole for hole sizes less than 25mm dia.

The official line is to use a perpendicular lead in although I tend to use an arc leadin. it depends upon your machines acceleration and if you have a tunable G64 (blended motion) on your cnc controller (linuxcnc + uccnc have the options).

https://www.hypertherm.com/Download?fil ... &zip=False

https://www.plasmaspider.com/viewtopic. ... 72#p166326
mcmental
2.5 Star Member
2.5 Star Member
Posts: 136
Joined: Thu May 14, 2020 10:06 am

Re: circle issues

Post by mcmental »

sorry, im using sheetcam and my software is commandcnc
User avatar
acourtjester
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 8183
Joined: Sat Jun 02, 2012 6:04 pm
Location: Pensacola, Fla

Re: circle issues

Post by acourtjester »

When I look at you cut images is seems there may be some slippage in your drive system. The ends don't meet the start, see attached as to what I mean. This could also be caused by your table wobbling, is it a bolted together type??
cut part.JPG
cut part.JPG (97.24 KiB) Viewed 4814 times
cut part.JPG
cut part.JPG (97.24 KiB) Viewed 4814 times
DIY 4X4 Plasma/Router Table
Hypertherm PM65 Machine Torch
Drag Knife and Scribe
Miller Mig welder
13" metal lathe
Small Mill
Everlast PowerTig 255 EXT
TJS
3.5 Star Elite Contributing Member
3.5 Star Elite Contributing Member
Posts: 764
Joined: Wed Nov 26, 2014 1:22 pm
Location: Fairfield, CT.
Contact:

Re: circle issues

Post by TJS »

As stated. Perpendicular lead in. I make them about .125" long or longer. I have no lead out on holes. Do not play with cut rules on Command CNC, they are built in. On thicker material you do want overburn I make the overburn about have the thickness of the material when using 1/4" or more. Slow the holes down to at least 50% of the book speed. Jim Colt wrote an article on holes on this forum and removing the divot. Make sure the gantry is square as well and your steps per rev are spot on.
T.J.
User avatar
SegoMan DeSigns
4 Star Member
4 Star Member
Posts: 984
Joined: Sat Jan 06, 2018 4:45 pm

Re: circle issues

Post by SegoMan DeSigns »

I rule that works for me is a straight lead in to a straight line and an arc into a curved line. Also when your in SheetCam make sure the pause at end of cut is set at 0 as well.
mcmental
2.5 Star Member
2.5 Star Member
Posts: 136
Joined: Thu May 14, 2020 10:06 am

Re: circle issues

Post by mcmental »

Thanks I’ll have a look through the settings and report back
User avatar
Joe Jones
5 Star Elite Contributing Member
5 Star Elite Contributing Member
Posts: 3486
Joined: Sat Oct 11, 2014 2:33 pm
Location: Franklin, KY., USA
Contact:

Re: circle issues

Post by Joe Jones »

acourtjester wrote: Tue Mar 22, 2022 9:41 am When I look at you cut images is seems there may be some slippage in your drive system. The ends don't meet the start, see attached as to what I mean. This could also be caused by your table wobbling, is it a bolted together type??
cut part.JPG
That was my first thought also. Either the table is not SQUARE square, or there is some slop in the X-Y mechanism, OR he could be using a full length machine torch and the torch is wobbling in the mount, allowing it to "cone" as it goes around the circle at a higher cut speed (G-forces).

The nick at the end of the lead in MIGHT be able to be reduced via corner acceleration. Perhaps the torch is spending too much time at the intersection? Cutting the amperage down a bit may also help.

I have a friend in Virginia who is also struggling with the shifted X start and finish points of a circle on a Samson 510 table. I might have to hop into my truck with the bin of spare parts and go see if we can isolate and fix the problem. Thankfully, my table has always cut round circles, so I cannot duplicate the problem here.

I want a LASER TABLE !!!

Joe



.
PlasmaCam 4x4, Samson 510 table, Go Torch, + more
AD-AH-AM-AN-3D-CS-MU-PC - Upgrades

X-TOOL D1 PRO (x 4) F1, S1 (x3), P2 (x2), F1 ULTRA (x2) with conveyors, M1 ULTRA (x2) + accs.
LaserPecker 1 PRO, LP-2, LP-4 + accs
50 Watt GALVO fiber
TYVOK Spider S1 60W Diode Laser 49" x 96"
SwiftShape 3-in-1 machine

CreatBot D600 PRO
Stratasys Fortus 400mc
BIGREP Studio Gen 2
MODIX Big Meter
MakerBOT Z-18 3D Printer

Bernardo Mach 55 TON Ironworker

FREE DesignEdge Training Online Via ZOOM!
adbuch
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 10138
Joined: Thu Sep 21, 2017 5:22 pm
Location: Tucson, Arizona
Contact:

Re: circle issues

Post by adbuch »

mcmental wrote: Tue Mar 22, 2022 12:49 pm Thanks I’ll have a look through the settings and report back
I will look forward to learning what you find out.
David
User avatar
ROKCRLER
3 Star Elite Contributing Member
3 Star Elite Contributing Member
Posts: 656
Joined: Sun Sep 30, 2018 5:19 pm

Re: circle issues

Post by ROKCRLER »

You didnt mention which table youre running, but for what its worth, I had similar circle cut issues, turns out my gantry got out of square, re-squared and now able to cut round holes down to .125 on .125 steel 45a regular consumables.
Im running a Dynatorch table.
4x8 Dynatorch
PM85
~Mo~
User avatar
Joe Jones
5 Star Elite Contributing Member
5 Star Elite Contributing Member
Posts: 3486
Joined: Sat Oct 11, 2014 2:33 pm
Location: Franklin, KY., USA
Contact:

Re: circle issues

Post by Joe Jones »

A gantry that is out of square may cause elliptical shaped holes, but that does not account for the inability to return to the starting point of a circle.

Joe



.
PlasmaCam 4x4, Samson 510 table, Go Torch, + more
AD-AH-AM-AN-3D-CS-MU-PC - Upgrades

X-TOOL D1 PRO (x 4) F1, S1 (x3), P2 (x2), F1 ULTRA (x2) with conveyors, M1 ULTRA (x2) + accs.
LaserPecker 1 PRO, LP-2, LP-4 + accs
50 Watt GALVO fiber
TYVOK Spider S1 60W Diode Laser 49" x 96"
SwiftShape 3-in-1 machine

CreatBot D600 PRO
Stratasys Fortus 400mc
BIGREP Studio Gen 2
MODIX Big Meter
MakerBOT Z-18 3D Printer

Bernardo Mach 55 TON Ironworker

FREE DesignEdge Training Online Via ZOOM!
User avatar
ROKCRLER
3 Star Elite Contributing Member
3 Star Elite Contributing Member
Posts: 656
Joined: Sun Sep 30, 2018 5:19 pm

Re: circle issues

Post by ROKCRLER »

Joe, i agree.. again, without knowing which drive system were all ASSuming.
Mine was cutting semi circular holes and i did notice a bit of start/end point issues, PM'd the bearings, gantry and belts and back in business.
I'm definitely a newb, but i have learned to check mechanics before messing with settings. One thing I've noticed with new users (not saying OP is a new user) is folks, me included thought/think the tables are simply press go and done. Once i started religiously PMing the machine my cuts and consumable life have improved greatly.

I'll go back to my corner now :ugeek:
4x8 Dynatorch
PM85
~Mo~
mcmental
2.5 Star Member
2.5 Star Member
Posts: 136
Joined: Thu May 14, 2020 10:06 am

Re: circle issues

Post by mcmental »

I’ll have to wait a few days to report back as my ankle is not very happy!
4328C769-5958-4169-B72D-6D71F4AB5EF1.jpeg
EE82BC0C-1035-4628-AE99-1EB59A47A2E4.jpeg
adbuch
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 10138
Joined: Thu Sep 21, 2017 5:22 pm
Location: Tucson, Arizona
Contact:

Re: circle issues

Post by adbuch »

What table are you using? Some photos would be helpful.
David
AJNess822
1.5 Star Member
1.5 Star Member
Posts: 25
Joined: Tue Oct 27, 2020 1:08 pm
Location: Minot, ND

Re: circle issues

Post by AJNess822 »

For anyone opening this thread for answers I was having troubles with cutting perfectly round circles after a system upgrade, turned out to be EMI problems, Electro Magnetic Interference, from all of the wires, and possibly nearby welding machines etc.. I installed a grounding rod into the concrete and grounded both my plasma, Accumove, and table together and that alone made the world of difference. Other problems cutting circle are of course, play/wobble in any table components, bad consumables, out of square like previously mentioned.
Bodor 12KW Laser Tabe (8'X20')
Lincoln Accumove 3
Hypertherm Powermax 1650
7'x20' Table (plasma and torch)
Mobile Welding (Miller Big 40)
Magnetic Particle and Liquid Dye Testing (Level II)
adbuch
6 Star Elite Contributing Member
6 Star Elite Contributing Member
Posts: 10138
Joined: Thu Sep 21, 2017 5:22 pm
Location: Tucson, Arizona
Contact:

Re: circle issues

Post by adbuch »

AJNess822 wrote: Thu Aug 04, 2022 10:48 am For anyone opening this thread for answers I was having troubles with cutting perfectly round circles after a system upgrade, turned out to be EMI problems, Electro Magnetic Interference, from all of the wires, and possibly nearby welding machines etc.. I installed a grounding rod into the concrete and grounded both my plasma, Accumove, and table together and that alone made the world of difference. Other problems cutting circle are of course, play/wobble in any table components, bad consumables, out of square like previously mentioned.
:Like :Like :Like
Post Reply

Return to “Plasma Cut Quality Forum”