Cutter not returning to exact starting point of the cut

[nsackman22 2]

On some cuts the knife does not return to the exact starting position of the cut. This happens on most round cuts, like a D an O or a period. The size of the text is either under half an inch or up to an inch and a half. I've tried numerous things like changing the speed, the pressure and the blade offset. None of these seem to be showing any type of improvement. The issue isn't so bad that there is a big section un cut, but just enough that makes weeding very difficult. I've used up yards of vinyl trying to figure out this issue before I start producing for customers.

I've attached both the SBD and the AI file. Please provide any help possible.

Cutter: MH721

Purchased: 12/19/2011

Connection: serial

Software: signblazer

OS: Windows 7

Material: Oracal 651

[Guest Finishing Touch]

Have you tried a new blade?, I had some issue after i used a chrome vinyl had to buy a new blade. Are there particular letters to this file that you are having problems with?

[nsackman22 2]

I just tried a different blade and got the same results. I'm using the ones that came with the cutter. Are these 45 degree blades? Would a different degree blade work better? I have only been cutting on the same piece of vinyl so I wouldn't think that I damaged the blade in any way. Issue seems to happen on any letter but in different severities. It always shows up in the same spot, where the cut starts and finishes. I've attached a picture of what the cut looks like after weeding. There are little pieces sticking out where the vinyl had to be torn/ripped when weeding.

[MZ SKEETER 4,708]

what do you have your blade offset set at? Also, the blade should barely be seen out of the end of the blade holder. You can take a scrap piece of vinyl and with the blade holder in your hand cut firmly across a piece of vinyl, should only cut the vinyl and barely or not at all, make a mark in the vinyl backing.

Also make sure there is not any vinyl pieces stuck in the blade holder,, a drop of 3-1 oil in blade holder can help to make the blade spin freely..

[FBRsportmod68 109]

i dont use anything other than a 60 degree blade...never had a prob like that. also using Sb and a mh-721 refine

[nsackman22 2]

Thanks for the replies everyone. Skeeter, my blade offset is set at 0.40mm. I didn't see a change between 0.25 and 0.40. The offset on the box the blades came in says 0.25-1.00mm. The blade was cutting through the paper backing but then I adjusted it just a tiny bit and now it's not. So i'm assuming that the blade depth doesn't have anything to do with this.

FBRsportmod68, the 60 degree blade doesn't come with the mh-721 i'm assuming?

[MZ SKEETER 4,708]

try going lower on offset.. at .05 intervals. definatley too high. what do the test cuts look like?

You still don't want too much blade sticking out, it will lift your vinyl. You only should be cutting with the blade tip.

[nsackman22 2]

So I've studied it a little bit and thought about what you guys have said to me and I think I have narrowed down what is happening. When the blade finishes a cut it is lifted and moved(or the vinyl is moved) to the start of the next cut. When it is set down it may or may not be rotated to the correct direction that it is going to be moved for that cut and it has to rotate to the new direction while the cut is started. When I look at the vinyl right after it is cut I can see a curved cut where I'm seeing this issue. This to me looks like the blade was set down and then rotated into the correct direction. Does this sound like something that might be happening? Is there any way to work around it? Is there something that I can change in signblazer to require that the next cut must be started in the same direction that the last cut ended?

[MZ SKEETER 4,708]

try a drop of 3-1 oil in the blade holder. Blade should spin freely, blade tip barely seen. Also what happened when you lowered the blade offset by .05 intervals. ?, And what do your test cuts looks like? From the test program on the vinyl cutter... are all corners sharp? or rounded? should be sharp. From the pictures on your design, the blade offset is too high.

[nsackman22 2]

I will try the oil, but i've got to find some first. Do you have any recommendations? I lowered the blade offset by 0.05 intervals from 0.4 to i think 0.2 and i saw no difference in the cuts. I'm entering the offset in the cutter setup in signblazer, is that correct? I haven't done test cuts but the corners are all what I expect in my design cuts. It's just this cut connection point that i'm having issues with. Thanks for responding Skeeter.

[MrMopar64 47]

Do you have over cut turned on? I don't use SB so not sure if it has one...

[MZ SKEETER 4,708]

you can find 3-1 oil most anywhere. Hardware, grocery convienence stores, etc. You need to do test cuts, with your vinyl cutter program. I believe yours are triangles, to get the correct blade offset. That is how you set your vinyl cutter up. You have to start there first. Signblazer does not have overcut. Make sure you don't have pieces of vinyl in the blade holder. Even a tiny piece can cause problems

[nsackman22 2]

I tried the oil. I put 1 drop in the blade holder and moved the blade around to make sure the oil got everywhere. This didn't seem to help the issue any. There is no vinyl stuck to the blade. My test cuts seem fine to me. I don't know what to try next. I think I'll call uscutter. I have been cutting anyways and just bearing with the issue in the weeding process.

[nsackman22 2]

I saw this in a different thread and it sounds just like what I'm experiencing. http://forum.uscutter.com/index.php?/topic/27292-vinyl-cutting-problem/page__hl__%2Bdifficult+%2Bweed__fromsearch__1

The very nature of a drag knife cutter causes some of this as it must drag the knife to turn the blade - when the blade drops it is turned in a different direction causing the little line off of the other area. some software has an over cut that will help with the weeding problem.

Does anyone have any other suggestions on how to work around it with SignBlazer?