need some help with V_carving

[TadasLT]

Hi ALL,
I have problems with V-Carving. At first look it looks easy, but I cant get it. What I'm doing wrong ?
Take a look:

Why wood so rough ?

I'm using this bit (8mm, 60 degree)

please give me some TIP / help / advice

Thanx,

Tadas M.

[tmerrill]

Tadas

I see two issues. The most important one is the bit you are using. That looks more like an engraving bit for metal. For wood, try to find one like this:

http://www.cmtutensili.com/show_items.a ... ~7/8/958~2

This is my favorite bit for V carving but other manufacturers make similar designs.

The second issue is tied to the first. That looks like a soft wood, which would definitely require a bit like the link shows. It appears your bit is tearing the grain instead of cutting it.

Tim

[TadasLT]

Thanx Tim for reply,

I'm using bit for wood (that says manufacturer)

take a look
http://www.freud.it/page39b.do?par5q=67 ... q.redirect

and yes I'm using soft wood. But I have try'ed on PLYwood - the results are same

Tadas M.

[tmerrill]

Yes, they do say that it is for wood. They also say it is for veining and engraving, which are normally shallow depths. Plywood probably isn't a good comparison as it normally is made of softwoods.

Try to find a piece of hardwood or plastic (corian, or another brand of solid surface countertop material, or even an inexpensive piece of plastic cutting board) and see what you get. If you get a better cut that shows a bit mismatch for the softwood.

With my experience with Vectic products, if the preview looks good, the software is doing its job. That leaves feed speeds, cut depth and RPM for the material you are using, bit selection and machine setup and operation. You can experiment with your feed speed and router RPM's to see if that helps or hurts.

Keep working at it and let us know what you try and the results.

Tim

[gravirozo]

hello

that bit a good brand... and it is one edged... as it gives clearer cut...
there are two thing could happen..... the bit is already used and the edge is dulled... it's don't need a lot to causing what is on the picture...

the other thing could be it is a "poor" quality material for engraving... what does not mean for furniture would not be 1st grade...

also can happen if the wood has humidity...around 20 percent still gives a feel as if it would be dried... but a fine line engraving already not possible...

thanks
viktor

i watched more the first picture.... might be the edge is the problem... it's don't cut clear... how much the rpm? is it enough? how about feed? for this size can be low...like 500-800 mm / min.... and rpm can be 14 K ....

[larrybadgett]

Looking at the size and length of the chips your travel or feed rate is way to fast for the RPM's of the cutting bit. What is your feed rate and RPM's?

[RoutnAbout]

I'd have to say that it has to be in your feeds and speeds.
You need more spindle/router rpms at the feed rate you were moving.

I looked at the image of your tool and there appears to be relief on the tool. But there isn't much. This can lead to rubbing on the heel of the tool (or the relief side).

While the tool your using will work for this kind of project, One like Tim pointed out will also allow you to Vcarve in a single pass. Those Freuds are pretty good for big box stores.

We all have been there, so don't stop asking questions.

[ManitobaKeith]

Tadas,
Try the Fish2 file I attached. I used just a V-Bit as a profile tool. Also changed the depth so it won't go so deep. You will probably want to change it back to MM also.

[TadasLT]

Hi ALL, I'm very very thankful for your reply's. Its very different forum that I have accustomed in Lithuania (here where I live, is no forum about cnc, but in other forums (like radio control planes, cars, etc) often redirecting to google.... and I hate that. So I'm very thankful for help guys ! I realy appreciate that.

So about my problem,
My feed rate is 360mm (as I'm using myself build cnc machine with cheep materials, but I have started a new project where my cnc will be all aluminum ) and using spindle speed about 16-18k rpm.
Yesterday, I have found a plexiglass in my garage, and tryed to vcarve on it. The results are much better, but after few seconds the router bit gets with melted plexiglass around, and started melting everything where its carving. I think with plexiglass is other story and needs other feed rates and spindle speed's (or other router bit).

As Viktor mentioned about router bit - the router bit is brand new, and this is his first cut and fail .
the material is a just some leftover from 3d project (with 3D I'm much better ). And material for 3D routing is very good. Its a Lithuanian July "Tilia cordata Mill".

In other hand, I dont know what exactly rpm I'm using. Becouse I'm using a KRESS router
http://www.kress-elektrik.com/Power-too ... howUid]=33
There are only digits on wheel and no explanation witch number what rpm gives. I have tryed with number "4" on my router .

Thanx for help guys,

Tadas M.

p.s. sorry for my English

And I wish to live in USA Does someone want to adapt a 28 year guy with wife and 4 month baby ???

[TadasLT]

Hi again,

today I have tryed to carve with slow speed and high spindle rpm. Same sh...t. Maybe I should get this tool:

http://www.cmtutensili.com/show_items.a ... ~7/8/958~2

Maybe it will help with Vcarving ?.
If not - I will burn my MDF CNC machine... I hate when I trying from heart and still no success.
Here is my CNC:

[tmerrill]

Sorry to hear you are still having problems.

Back to the bit, I personally would not use that bit for what you are trying to do. I don't even own a bit like that and probably have over 100 bits in my collection. I would really like to see you try your cut again with a better bit and tell us how it goes.

Sorry about the plastic cutting issues. You picked a hard type to start with. I know I recommended trying it, but was thinking more along the lines of corian or PVC, both of which machine great.

Keep us informed, we are here to help and I believe we can find a solution.

Tim

[tmerrill]

Tadas,

I just had an idea (brace yourself!).

If you don't have another type of V-bit and can't get one soon, try running your V-carve toolpath using a small diameter straight or round nose bit (you said you did 3D images better, so I assume you have both these type of bits). You already have the piece of wood shown in your initial post, so just use that over.

Obviously the results you get won't look like v-carving, but we are simply trying to confirm or eliminate the bit as an issue. If your cut looks bad with a different bit, then we are back to cutting parameters and machine. If the cut looks good, we know the issue was with your V-bit.

Keep us posted.

Tim

[larrybadgett]

Tadas
You didn't by any chance end up with a CCW cutting edge instead of a CW cutting bit. Check to see if the leading edge is CCW or CW. I once had CCW bits delivered by mistake but noticed it before i used them.

[cabnet636]

dont worry, cnc is a learning curve that only benefits thru pain!!!

been there done that, your machine will do this, the first file i ever ran took 10 hours to run a set of letters about 7" long x 2" tall, then i learned what stepover was!!

jim

[jhop]

Don't scrap your machine yet. The picture shows it seems to be tracking just fine. Like Tim said get a good bit for V-carving.

Jim