Cut parts are not correct size
Cut parts are not correct size
Hi all I have a smurf HWQ330 cutter and I have drawn a part in cad, transferred the DXF file to AI and then sent AI file to the SCAL4 software. Cut it in the smurf and it is correct in width side but 1.5mm shorter on the height. Im also suffering with rounded corners and lines not fully cut. I am also cutting 300GSM cardstock. Can anyone help me please?
Re: Cut parts are not correct size
First of all, make sure the W and H on screen in SCAL is exactly what it was back in your CAD program because sometimes file conversions can alter original design dimensions.
Assuming that's not the issue then...
Cutters need to be calibrated for the sizing resolution. In SCAL, go to Cutter>Cutter Settings OR in the Cut Settings window, click on the Settings button to the right of where you have the Model selected. In the top left corner you'll see X Resolution and Y Resolution.
The way to calculate those two Resolutions is to add something like a 10" x 10" square in SCAL OR use mm and make it 250 mm x 250 mm. You want it fairly large to get a more accurate result. Then you cut it out and measure it as accurately as possible with a ruler. Now, you need to know if YOUR model has X going up-and-down or left-to-right as you face the cutter... and then Y would be, of course, the opposite. It varies based on the brand and model but, in general, X is up/down on a vinyl cutter so assume that if you don't already know for sure or your user manual doesn't specify.
So, the Resolution is a ratio: (Measurement on screen) divided by (Measurement of actual cut) times (Current Resolution entered in SCAL) So, if your first cut of a 250 mm square indicated that X was ~ 248.5 mm, then your calculation would be:
250 / 248.5 x 1 = 1.006
That's the number you would enter and you would then repeat the cut. Let's assume that the next cut measures at 249.5, then the calculation would be:
250 / 249.5 x 1.006 = 1.008
And you continue until both sides are perfect.
Assuming that's not the issue then...
Cutters need to be calibrated for the sizing resolution. In SCAL, go to Cutter>Cutter Settings OR in the Cut Settings window, click on the Settings button to the right of where you have the Model selected. In the top left corner you'll see X Resolution and Y Resolution.
The way to calculate those two Resolutions is to add something like a 10" x 10" square in SCAL OR use mm and make it 250 mm x 250 mm. You want it fairly large to get a more accurate result. Then you cut it out and measure it as accurately as possible with a ruler. Now, you need to know if YOUR model has X going up-and-down or left-to-right as you face the cutter... and then Y would be, of course, the opposite. It varies based on the brand and model but, in general, X is up/down on a vinyl cutter so assume that if you don't already know for sure or your user manual doesn't specify.
So, the Resolution is a ratio: (Measurement on screen) divided by (Measurement of actual cut) times (Current Resolution entered in SCAL) So, if your first cut of a 250 mm square indicated that X was ~ 248.5 mm, then your calculation would be:
250 / 248.5 x 1 = 1.006
That's the number you would enter and you would then repeat the cut. Let's assume that the next cut measures at 249.5, then the calculation would be:
250 / 249.5 x 1.006 = 1.008
And you continue until both sides are perfect.
Sandy McCauley
Owner of http://www.iloveknk.com/
Owner of http://www.iloveknk.com/
Re: Cut parts are not correct size
Thank you so much I will try this and report back.
What about the lines not having a full cut and the rounding off of the corners? Can you help with these also?
What about the lines not having a full cut and the rounding off of the corners? Can you help with these also?
Re: Cut parts are not correct size
Sorry! Forgot to answer that part. This issue is typically caused by not having the proper Blade Offset and Overcut settings for whatever blade you're using. Blade Offset improves the sharpness of corners and Overcut helps complete closed shapes.
In the Cut Settings window, start with Offset = 0.3 and Overcut = 1 mm. If you find that your corners are still slightly rounded, then try Offset = 0.4 or higher. If you find "bubbles" appearing at the corners, then use a lower Offset (0.2). And you might need a "half setting" such as 0.45.
Overcut is typically just fine at 1mm. But if you cut REALLY large shapes, say a 10" circle, you might need to increase that, so try 2mm.
In the Cut Settings window, start with Offset = 0.3 and Overcut = 1 mm. If you find that your corners are still slightly rounded, then try Offset = 0.4 or higher. If you find "bubbles" appearing at the corners, then use a lower Offset (0.2). And you might need a "half setting" such as 0.45.
Overcut is typically just fine at 1mm. But if you cut REALLY large shapes, say a 10" circle, you might need to increase that, so try 2mm.
Sandy McCauley
Owner of http://www.iloveknk.com/
Owner of http://www.iloveknk.com/
Re: Cut parts are not correct size
Hi Well I did the 254mm/10" square and this is the results below. It isnt even square let alone the correct sizes for the sides. Do you have any ideas as to why is isnt square???
Thank you for your help so far but once again any help would be appreciated.
Thank you for your help so far but once again any help would be appreciated.
Re: Cut parts are not correct size
Did you read my additional post when I realized I had forgotten to address the Blade Offset and Overcut issue?
If the left/right sides and up/down sides are not the same length, that is an issue with the cutter. Here are some things to check:
(1) Pinch wheels are not centered with the grit shafts below. If even one pinch wheel is half/on - half/off a pinch wheel that can lead to skewing
(2) Make sure the pinch wheels and grit shafts are clean and not at all sticky
(3) Don't use a really high speed.
(4) Make sure the blade isn't over extended. If you are cutting vinyl, then make sure the blade isn't penetrating the backing sheet. If you are cutting paper, the paper should be mounted onto a cutting mat and not cutting into the mat at all.
Personally, when I calibrate a new cutter, I use the test pen and paper in order to minimize anything related to (4). Also, with a pen you don't get rounded corners at all because pens do not need a Blade Offset setting. If your cutting came with a test pen, try that but still keep the speed moderate.
If the left/right sides and up/down sides are not the same length, that is an issue with the cutter. Here are some things to check:
(1) Pinch wheels are not centered with the grit shafts below. If even one pinch wheel is half/on - half/off a pinch wheel that can lead to skewing
(2) Make sure the pinch wheels and grit shafts are clean and not at all sticky
(3) Don't use a really high speed.
(4) Make sure the blade isn't over extended. If you are cutting vinyl, then make sure the blade isn't penetrating the backing sheet. If you are cutting paper, the paper should be mounted onto a cutting mat and not cutting into the mat at all.
Personally, when I calibrate a new cutter, I use the test pen and paper in order to minimize anything related to (4). Also, with a pen you don't get rounded corners at all because pens do not need a Blade Offset setting. If your cutting came with a test pen, try that but still keep the speed moderate.
Sandy McCauley
Owner of http://www.iloveknk.com/
Owner of http://www.iloveknk.com/
Re: Cut parts are not correct size
Hi Sandy
Once again thank you. I bought a pen holder for the cutter and got it all setup and it now draws a perfect square the correct size too. So I guess my issue is with the blade/holder. I have 45*, 50* and I believe 55* blades so I will just have to keep trying the blades, offset, overcut and maybe less weight and double cut.
If you have anything else you can share I would be very grateful indeed.
Regards
Ken
Once again thank you. I bought a pen holder for the cutter and got it all setup and it now draws a perfect square the correct size too. So I guess my issue is with the blade/holder. I have 45*, 50* and I believe 55* blades so I will just have to keep trying the blades, offset, overcut and maybe less weight and double cut.
If you have anything else you can share I would be very grateful indeed.
Regards
Ken
Re: Cut parts are not correct size
Most likely your blade offset will be between 0.3 and 0.6. You only need to get the Offset to the nearest 0.05 mm... thus for each blade it will be one of these values: 0.3, 0.35, 0.4, 0.45, 0.5, 0.55 or 0.6. Only a 30 degree blade tends to be higher at, typically 0.75 mm and only special detail blades tend to be lower than 0.25. Again, just look at the corners of a cut square or rectangle and if they're rounded, increase the Offset. It they're bubbly/extended, decrease the Offset. And remember that a lot of inexpensive cutters can't cut really tiny lettering... so don't have high expectations on lettering smaller than about 1/4" unless you paid quite a bit for your cutter.
Sandy McCauley
Owner of http://www.iloveknk.com/
Owner of http://www.iloveknk.com/
Re: Cut parts are not correct size
Well although I got a perfect square with the pen. I can get a perfect square if I have very light cuts but it wont cut through the card even with 10+ passes. If I increase the cutting force it all goes PeteTong. I have found that the cutting mat goes into the cutter nice and square but when the cut is finished its has skewed by about 5 degrees. I cleaned all the pinch rollers and fitted a new blade bit I cannot get the thing cut out at all. Its really doing my head in now as I have been messing with this for about 20 hrs now and not cut a single piece out that is accurate.
Re: Cut parts are not correct size
What weight or thickness of card are you cutting?
And are you making sure the blade tip isn't too close to the card before cutting?
Typically, when cutting heavier materials, you need some "punch room" to maximize the downward force being applied to the material. This varies by cutter but here's a video to illustrate the point.
https://vimeo.com/43639078
On the other hand, the fact that the mat is skewing is indicative of the blade being force too deep and/or too fast through the material. It simply cannot cut and the mat will skew, as a result. Reasons for this: the cutter doesn't have a high enough force (drag blade cutters vary between ~200g and ~2000g) or possibly the blade is damaged, or the blade holder is faulty.
Sandy
And are you making sure the blade tip isn't too close to the card before cutting?
Typically, when cutting heavier materials, you need some "punch room" to maximize the downward force being applied to the material. This varies by cutter but here's a video to illustrate the point.
https://vimeo.com/43639078
On the other hand, the fact that the mat is skewing is indicative of the blade being force too deep and/or too fast through the material. It simply cannot cut and the mat will skew, as a result. Reasons for this: the cutter doesn't have a high enough force (drag blade cutters vary between ~200g and ~2000g) or possibly the blade is damaged, or the blade holder is faulty.
Sandy
Sandy McCauley
Owner of http://www.iloveknk.com/
Owner of http://www.iloveknk.com/