what is causing these marks please

Indy Joneds

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my phone can not take pictures close enough to show you the actuall script cuts , so ive drawn them as best i can . almost all done with a flat graver , 40 face / 10 -20ish radused heel . with lube/oil

thank you
 

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DAK4442

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I had what I think was a similar issue when I started bright cutting. I figured out that as I was "kicking/popping" out of a counter clockwise bright cut I was making as odd movement with my wrist (twisting action) causing the bottom left edge of my square graver to contact the opposite edge of my cut. The fix for me was to make a hundred or so counter clockwise bright cuts back to back on practice plates until the marks finally disappeared??? Kind of like golf...find the right way to do it then do it enough times to get muscle memory. The mark still shows up now and then when I'm not paying attention just like my occasional fade on a dog leg left...:)...Dan
 

Kevin Scott

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I hand push using a square graver for script, which not what you are doing. I do get that result sometimes. My theory is it happens when I am trying to lay the graver over too far in relation to how deep I am going. The deeper the graver cuts, the further you can lay the graver over.

Some people might say it happens because the heel of the graver leaves the bottom of the cut. I think that is the same as above.

Or maybe I am wrong about what is happening to you, or not interpreting the drawing correctly. Or just wrong.
 

Sam

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Heel drag of course. You might be cutting too deep to get the wider cuts as opposed to keeping the same depth and rolling the graver over. This is very difficult to troubleshoot with photos or drawings, but from experience I can tell you that this happens to many of my students when they try to make wide cuts with the flat graver. Instead of rolling the graver more, they maintain the same angle and just cut deeper to make it wider, and this is often the result.

It could also be the size of the heel. Keep it to about 1/4mm in size. Also experiment with different sizes to find the sweet spot for your work. Too short and it will bury into the work. Too long and you can get heel drag. Some experimentation if often necessary.
 

Andrew Biggs

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Try a smaller heel and when you are cutting very tight turns, lift your hand to a steeper angle as you start going around the cut.

It could also be that you are moving your hand slightly when cutting curves. Keep your hand/wrist rigid and move the vise into the cut.

Cheers
Andrew
 

Indy Joneds

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thanks DAK and Kevin and ZZ

I think thati must be doing what DAK is decribing and laying my graver over and contacting the metal on the inside of the cut . which i think is what Kevin in describing too ? but maybe my heel is leaving the bottom of the cut ? but how would i resolve that ?
i will try and watch for laying the graver over to much tomorrow and see if i can identify my errors.
 

Indy Joneds

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sorry just seen SAM and Adrews post . i will take your advice on board , I have experimented with the radius heel but always kept it 1/4 mm . But i understand what your saying about going to deep . and Andrew i will watch for hand wrist movements.

THANK YOU
 

monk

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make sure your graver is aligned with the cutting line. still cut, but if the graver misaligns off axis of the cut, rough edges will occur. esp true for me whilst using a 90 or 116.
 

Chujybear

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saw a video w chris decamalis (i think) where he demonstrates elbow raising (or maybe dropping?) as a common cause of that heal drag chatter marks.
 

Indy Joneds

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SO DAK4442 you are right... the cause is Edge drag . the marks are caused by the lowest edge of the graver bumping/cutting into the outer edge of the cut. I believe lowering the graver is the primary reason for this occurance but alsoa twisting motion could play a part.
when cutting at a depth that I percieve to be normal for me and my script cuts this has been occuring . What works for me is ,if you raise your heel angle from 10 - 20 . too more like 20/25 - 40 that you will eliminate this edge drag because your graver will be higher and inturn the lowest edge that was previously contacting will be higher.I can cut with a 10/20 heel but only until i want to exit the cut and i raise the cutting edge upwards and ultimately the lowest edge downwards and into the metal which leaves the edge drag marks. your graver is higher when entering ., then lowers to the normal cutting depth then lowers again when leaving , a scooping motion is required so i had to higher the angle . an alternative maybe to grind away this edge but not near the point and only by a 1mm at a guess.
monk i see what your saying . and chujy im now certain its ( dropping )
Just thought i share my findings from these past stresful angry confused days.

Thank you for all your wisdom

Indy
 

monk

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SO DAK4442 you are right... the cause is Edge drag . the marks are caused by the lowest edge of the graver bumping/cutting into the outer edge of the cut. I believe lowering the graver is the primary reason for this occurance but alsoa twisting motion could play a part.
when cutting at a depth that I percieve to be normal for me and my script cuts this has been occuring . What works for me is ,if you raise your heel angle from 10 - 20 . too more like 20/25 - 40 that you will eliminate this edge drag because your graver will be higher and inturn the lowest edge that was previously contacting will be higher.I can cut with a 10/20 heel but only until i want to exit the cut and i raise the cutting edge upwards and ultimately the lowest edge downwards and into the metal which leaves the edge drag marks. your graver is higher when entering ., then lowers to the normal cutting depth then lowers again when leaving , a scooping motion is required so i had to higher the angle . an alternative maybe to grind away this edge but not near the point and only by a 1mm at a guess.
monk i see what your saying . and chujy im now certain its ( dropping )
Just thought i share my findings from these past stresful angry confused days.

Thank you for all your wisdom

Indy

sort of like riding a bike. too many things to think about when beginning. then one day, it just starts to happen. that is when you begin to enjoy the ride:biggrin:
 

silverchip

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Ina addition to the remedies for heal drag, you might be trying to torque your wrist during the cut. Hold the tool and turn or move the vice into the cut.
 

Bluetickhound

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Bump master Bluetick strikes again!! I have been experimenting with different graver geometries (even trying what I think is a close facsimile of a Speitzer) but no matter what I whip up, they all suffer from varying degrees of heel drag. The only way to avoid it is to make such shallow cuts they have no sparkle or character at all... If there is any depth of cut.... Heel drag. I have tried raising my AOA, lowering it, nothing seems to result in what I would call a nice cut. Rolling into the cut, rolling out, no joy. I get that I'm only two weeks in here so I'm not discouraged in the least but reading this thread has given me some ideas to try tomorrow (I've been at it all day, wife says time for a break!!) and I thought it might help some of my fellow noobs who may be suffering the same plague.
 

monk

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Bump master Bluetick strikes again!! I have been experimenting with different graver geometries (even trying what I think is a close facsimile of a Speitzer) but no matter what I whip up, they all suffer from varying degrees of heel drag. The only way to avoid it is to make such shallow cuts they have no sparkle or character at all... If there is any depth of cut.... Heel drag. I have tried raising my AOA, lowering it, nothing seems to result in what I would call a nice cut. Rolling into the cut, rolling out, no joy. I get that I'm only two weeks in here so I'm not discouraged in the least but reading this thread has given me some ideas to try tomorrow (I've been at it all day, wife says time for a break!!) and I thought it might help some of my fellow noobs who may be suffering the same plague.

learning this craft takes a very long time. even for those getting pro instruction. thinking that one is going to learn the art overnight,is a guarantee in frustration. taking solace in what one learned today, then using it tomorrow. and on it will go. relax, and above all, learn to enjoy what you're doing.
 

Bluetickhound

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Understood, and I appreciate what you're saying. I'm enjoying myself immensely and am seeing improvement every day. I'm sure at some point I'll "plateau" and experience some frustration (like everyone else who has done this, I'm sure!!) but keeping at it is the way to push through them. I'm really thankful for the resources available to me here and elsewhere that were only a dream for the folks on whose shoulders I now stand. The learning curve is still steep for a hand push guy like me but not nearly as steep as it could be (and has been) for others before me.

As far as the heel drag issue goes, I polished the heel pretty good, not mirror bright but well enough to remove most of the grind marks and it helped tremendously. Lesson learned! I'm keeping a notebook to write down the things I'm picking up along the way and in the future I should have enough notes to categorize them on the computer for easier access.
 

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