Sure Can Use A Tip Today!

This forum is for users to post tips and tricks they have found useful while working with VCarve Pro
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VE5MDH
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Sure Can Use A Tip Today!

Post by VE5MDH »

This is what VCarve says my project should look like...
This is what VCarve says my project should look like...
This was my outcome...
This was my outcome...
As you can clearly see, there is much to said about the clean-up on this job.
0.25" EM Used as the (Clear) Pocket tool
0.125" EM Used as the Main Pocket tool
90 deg V Bit used as the Pyramid Cutter

I do have 0.0625" & 0.03125" available, and I believe both as EM & BN Bits. BN for sure, though.

Before I ask my obvious question, why did the 0.125" EM not cut as deep as the 0.25" EM??? I think this I need to understand better. Yes, I did a ZERO, ZERO (Zero the Bit, then Set ZERO to 0,0,0. To me that looks like a BIG Drop-off left behind from the 0.125" EM!


Now for my question... Just how do I go about cleaning up this mess left behind? Do I just change the tool bit (the 0.125", 1/8" bit) to a 1/16", 0.625" bit and re-calculate the new toolpath, save that toolpath, and name that toolpath to say "4 Pocket EM (or BN) 0.625.gcode"???

This is the only way I can figure on this happening.

And for good measure... this is just being cut into Pine for now (rather waste that than Oak, Maple or the exotics, like Wange, Purpleheart Padauk amongst others) - what would the recommended Feeds & Speeds for both Pine/Fir/Spruce & Oak woods. Right now, I'm just using Speed #6 and speeds between 80 & 95IPM (until I can determine or receive confident information otherwise).


Thanks for your feedback, and your time taken today!

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Leo
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Re: Sure Can Use A Tip Today!

Post by Leo »

How do you set the "Z"?

It looks like there was a difference in the setting on the "Z" axis between the 2 cutters.

To fix it, you can recut the pocket a little deeper with a 1/8 cutter. Just use one cutter.

Look at this thread - for cutting parameters
http://forum.vectric.com/viewtopic.php? ... ad#p218700
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VE5MDH
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Re: Sure Can Use A Tip Today!

Post by VE5MDH »

I agree with you Leo, but this is not the case.

I probe the bottom of my bits to a ref line on my waste. It is one inch X+ from the machine's X=0. Y is about 4"+ from its Y=0. Z= the top of my wood (1 by Dim Lumber, which is about 0.74" - 0.76" (I guess whoever was manning the saw on the particular day).

Both the 0.25" & 0.125" were Zeroed on the same ref point. Then I go into the SET ZERO on my Carbide 3D Carbide Motion software. This I ensure, only due to the quantity of wasted projects to date (4 I think). One is bad enough to waste away.

---

Leo, so correct me if I'm misunderstood, but all you are saying is that I can just return to my 0.125" gcode file, and instead of it dropping to 0.25" (as both cutters are programmed for), all I need do is to enter in a value of 0.27" run it again (or I could take my digital calipers, and measure out the Drop Diff).

And away I go! Hey, that could work out.

I'll post a pic of the outcome.

Thanks for your thoughts, Leo!

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Re: Sure Can Use A Tip Today!

Post by ElevationCreations »

I agree with Leo, it looks like the zero between 1/4” and 1/8” are off. Are you using a touch plate to zero Z to the surface of the stock or using a different method? You could also be losing steps on your Z if the belt isn’t tensioned properly or pulley set screw is loose.

My method to correct would be to surface the entire board taking off the amount of difference of two pockets plus an additional .002 to .004”, then rerun the jobs and use one bit for roughing/clearance as Leo suggests.

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Re: Sure Can Use A Tip Today!

Post by Leo »

When you say you "probe" the bits to a line. Please elaborate on that, in detail. Do you have a tool touch probe? Is it possibly moving?
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Re: Sure Can Use A Tip Today!

Post by dwilli9013 »

This could also happen depending on the rigidity of your machine. If you are using a 3 or 4 flute 1/4 inch em then it could quite possibly be pulling itself down into the material.
I have had this happen to me with corian if I cut to agressively. I am not in this for a living so slowing it down and backing off the feed rate go me back to a glass state.

I literally just finished the attached tonight. It will take me about 20 minutes clean up before it is ready for contrasting stain and a good antique oil finish.
I use a 1/4" 0 flute endmill for large area clearance and a 15 deg engraving bit for the finishing angles and outer v groove.
This was done in 7/8" cherry with good results.
I agree your piece is definitely savable just have to hit it again. Luckily you used a practice piece rather than an exotic to start.
Thanks for sharing.
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VE5MDH
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Re: Sure Can Use A Tip Today!

Post by VE5MDH »

Leo wrote:When you say you "probe" the bits to a line. Please elaborate on that, in detail. Do you have a tool touch probe? Is it possibly moving?
Sorry Leo, no I do not have a touch probe. I use the word probe to pinpoint a spot where one aims for to zero XYZ. Simple as that.

What I have noticed is the 12" x 1" (11"x.75") was cupped and it pulled my 1.25" brad nails up out of my waste board. At what point did the warping of the wood occur? I don't know. BTW, speed on this job was at 80IPM.

I do not understand though why when I returned to the program and changed Start to 0.25" and Bottom depth to 0.325" that the bit cut the rectangle around the word "Harley-Davidson". Yet the bit dug into the wood to 0.625"+!!! Very unacceptable.

I decided to flip this fail over and use a 20 deg engraving bit. Start at zero cutting into a max depth of 0.1". I decided to experiment with a Profile Cut, cutting the line ON the line. 40IPM and turned the 611 down to speed 5. The outcome was very nice for what my Wife wants to do to the cut. So, if its good enough for her to work her Pyrography with, well who am I to argue, right?...

Moral of this story is KISS. Oh, and ensure your wood selection is FLAT! I'm most certain that this was the leading factor to my Fail.

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Re: Sure Can Use A Tip Today!

Post by ElevationCreations »

Carbide3d has a speeds and feeds chart for the SO3. It’s listed in the documents section on their website. The recommendations are a good starting point for the machine.

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Re: Sure Can Use A Tip Today!

Post by Leo »

VE5MDH wrote:
Leo wrote:At what point did the warping of the wood occur?
Ahhh yes of course. Anytime you cut out a pocket and remove a large percentage of wood from one side and not the other side, warping can be an issue.

Sooo, when you touch off the tool, do you use a piece of paper, or a shim, by eye, or do you just touch to the wood?
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VE5MDH
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Re: Sure Can Use A Tip Today!

Post by VE5MDH »

Leo wrote:
VE5MDH wrote:
Leo wrote:At what point did the warping of the wood occur?
Ahhh yes of course. Anytime you cut out a pocket and remove a large percentage of wood from one side and not the other side, warping can be an issue.

Sooo, when you touch off the tool, do you use a piece of paper, or a shim, by eye, or do you just touch to the wood?
Sorry for this delay, Leo.

I use both methods A) & B). A) = Normal Copy Paper, ripped into 1.5" x 6" strips. B) = Sometimes I have used a MagLite and watch the shadow of the tip of the tool and tool meet at the point on the wood. I like using A) more so, though. I drop the tool until the paper has a rough resistance when I slide the paper fore & aft (Where I can still slide the paper out from under the tool in question). I know that if and when I am able to score one of those Touch Probes, my issues of seeing gauge marks between tool changes would be extinct.

It was sure strange. The cupping (rings on the wood face down, wood warps in the opposite direction). It should also be noted that in the past couple weeks, we have had above normal high temperatures for Western Canada! More like Arizona Temps, than Saskatchewan! 35 - 42 deg C (Well over 100F). My practice wood that I purchased from the Home Depot just may have had the moisture content of the wood evaporate from it, and with the depth of the pocket of the cut, that just may have been too much for my wood.

I wonder about spraying down my wood, then letting it dry out before I cut into it? My luck, it would just warp & twist the wood into unusable hockey sticks (as we call this type of wood). Just to bump up the moisture content of my wood.

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Re: Sure Can Use A Tip Today!

Post by Leo »

The touch off method with paper is usually pretty sound.

Lots of times I just touch the tool tip to the wood. Most times there is nothing so critical that .005 will matter.

When matching two tools is does matter. Accuracy as close as possible is critical.

I see two things happening.

1) the rough tool removes a volume of wood, and the wood moves, during that cutting.

2) you change the tool, but the wood has moved , swelled, warped whatever you want to call it. You touch off the tool to the same X_Y location but the "Z" is a tiny bit different because of the movement, and they no longer match.

Wood movement is a random action. The only thing we can do is to know that and to find a work around.

I have done the same thing many times over and over. Best work around I can find is the cut the entire pocket a little deeper with the smaller tool AFTER, letting the wood sit sticked in the shop AFTER the rough cut.

BTW - I am not so partial to the tool touch probes - BUT - I like this thing. I set the tool to less than .001 each and every time. On Mach 3 I touch the tool and step down to zero, then I set 2.000 in mach3.

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Re: Sure Can Use A Tip Today!

Post by NormanAlbert »

I find that when doing wood with multiple tools I zero at the bottom left corner of the job. The wood is most always a larger dimension in x and y and that is where my hold down screws go. I give myself an x as close as possible to the left bottom screw as my zero point for x,y,z. Even as wood moves from having internal stress relieved the area near the hold down screws will remain stable. One last thing, use screws, not nails. Nails only make a hole.Norm

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