Spring loaded engraver??

[jaru-eri]

Are there anybody here who have tried one of these in order to make scrimshaws? Are they accurate enough or will there be any kind of play when thay have been used a number of times?

https://www.ebay.com/sch/i.html?_from=R ... r&_sacat=0

[martin54]

Lots of people using drag engraving bits, mine doesn't get used that often but I have never had any problems with it. I noticed when I bought mine that some of the cheaper ones had an aluminium body. I would avoid those as they may well cause problems over time

[GEdward]

I have the Canadian made CNC-aid and I like it. Like Martin54, I don't use it a lot but I have not had any trouble with run-out so far. I do dial indicate all my tools at the spindle to within 0.001 T.I.R. or less if I can get it. The nice part about this particular set is the variety of springs that go with it. You can pretty much fine tune the pressure to engraving granite ( rotation not recommended ), which I have done, to aluminum, plastic etc.. It comes with grease and I find that if you use a dust collection shoe, dust will pull up onto the shank. Depending on how abrasive the dust is, keeping shank wiped down and regular application of fresh grease will go a long way toward extending the service life.

Ed

[martin54]

The nice part about this particular set is the variety of springs that go with it.

Haha, when I bought mine I couldn't find many in the UK & the one I ended up buying had an HGV suspension spring in it
I think it was meant for engraving hard metals on a mill rather than a CNC router with acrylic & other softer materials, first thing I did was measure the spring & then go out & buy a few at different gauges

[VUserCKA]

Hello to all.
I am only a year into my CNC learning endeavors and am still a newbie, but...I recently purchased a spring loaded engraving tool from CNC-Aid. I like it a lot and have have great results with pretty much first time use and it solved some other problems with microscopic surface level variations and DOC. Used the heck out of it right out of the box to engrave text and simple clip art images on 50+ credit card size aluminum blanks. I think it is worth the money, although since they have a minimum purchase if you order accessories you should get the additional diamond bit along with the original kit and maybe extra springs if you think you may need them. Then you avoid more shipping and minimum purchase limit later on.
I also purchased a diamond drag bit from Carbide 3D. It worked great for one short line of test text I tried, but now I have maybe a problem but definitely some questions if anyone has already figured this out.
First question: even though I had the spindle speed at zero (the diamond drag bit is not supposed to spin), my CNC still ran the spindle at 1000 rpm. I'm using V-Carve pro and Mach3 controller and the bit is configured in the tool database with spindle rpm of zero. I doublechecked my toolpath setup in V-Carve. Maybe there is a Mach3 setting I need to learn about. I got by this by unplugging the cable to the spindle so at least I can manage this issue, but the next question is killing me...
Second question: If my project is open and I have no specific toolpath operation selected my tool database displays the Specialist tab with both my diamond drag bits, 90 deg and 120 deg. If I choose the Quick Engrave toolpath operation my specialist bits are available to choose from within the Specialist tab. If I have Profile or V-Carve engraving toolpath operation selected, the tool database shows a specialist tab but I can't figure out how to add the diamond drag bits. When I go to add a new tool the tool type drop down does not display a choice for diamond drag but from within the Quick Engrave toolpath operation the choice is available. If V-Carve software only allows drag bit on profile cut that would explain it but I think it is my knowledge limitation rather than the software.
If anyone can help with this I would be very grateful.
Thank you
Charles

[Xxray]

Don't know what a scrimshaw is but everyone should have a drag bit, I use mine mainly for edge lit acrylic work but they can etch a variety of surfaces. Tips last forever, I never worried much about the amount of spring pressure and tend to adjust that in software [depth of cut] which obviously, is very small. Can also adjust it to your liking with more or less pressure when setting Z, really not that much of a factor because if its etching, a little more or less won't make any noticeable difference.
Spring loaded feature in theory could come in handy for uneven surfaces, but you generally should not have uneven surfaces in 2D CNC work, but there are always 1 off exceptions, maybe like a rifle stock or something [which would be better suited to a TBN anyhow I would imagine] - They can accommodate minor "textures" lets say but reach their limits quick, say if you go off the edge of a workpeice they will probably snap when going back on.

[VUserCKA]

Very nice edge lit acrylic projects! I really want to try and make something like that.
What type of toolpath operations are you using?
I'm unable to select the diamond drag bit from my tool database for any toolpath operation other than the 2d profile toolpath. I feel like I must be doing something wrong.
Do you have any advice?
Thanks
Charles

[VUserCKA]

My apologies, I had that wrong earlier...
The quick engrave is the only operation that shows the drag bit within the specialist tab, the other toolpath operations may show a specialist tab but no drag bits. If you open the tool database without having a toolpath operation selected the drag bits are visible in the specialist tab. Read through everything in the VCarve user guide related to tool and material management and couldn't find any answers.
Thanks for any advice.
Charles

[Xxray]

I typically use a profile toolpath, and select "Engrave (20' 0.02" Tip Dia)" for the bit. Don't know why a drag bit is not allowed but it really doesn't matter.
That is for all lines, if there are areas to be filled then you use a pocket toolpath [or quick engrave], often I'll use both [profile and pocket] on a project

[martin54]

Not all tools are suitable for all types of toolpath which is why when you select a particular type of toolpath certain tools might not be visible when the tool database opens
Why a drag bit is not available in a profile toolpath I have no idea but as Xxray has already said he selects an engraving bit which I am guessing has a similar geometry to his drag bit

[VUserCKA]

Thanks for both replies. It took me all day to finally figure that out...the drag bit is limited to the Quick Engrave toolpath operation.
I did find a workaround, which is what was suggested, use a v bit or engraving bit setting with the same geometry. Maybe my next sign should be a "BANG HEAD HERE" sign

[Xxray]

Yes must be similar, all I know is I tried it long ago and it worked, I tend not to question success.

Some folks may feel a bit guilty or sneaky "cheating" but they have to understand, not only trial and error is required in CNC work but also improvising, the tools and software are our servants to be commanded as we please.