How to keep from burning on Centerline?

[Underdog]

Did I make a mistake by setting up my centerline cuts to "best"?

If I set it back to "normal" or... (what is the lowest setting?... is it "fast"?) or whatever the lowest setting is, will it burn less?

[DocWheeler]

When compiling the mpc to your card, try changing the quality from one to another.
If I remember correctly, the time does not change for centerline-only carves.

Edit: I later found that I was wrong about this.
For the text only, the time varied from 26:21 to 29:25 (Draft to Optimal)

[Underdog]

Actually it did change, but only by a few minutes for each step up.

There were only the centerline cuts and the perimeter cut on this. I did no carving.

[Deolman]

Is your bit dirty or dull. Has your bit been dropped or banged around in a drawer. I haven't seen any problems of burning on the centerline projects I have carved. (That doesn't mean it won't burn in the future.)

[unitedcases]

How big are your letters? Which bit, 90? Big letters will take quite a plunge and type of wood will effect as well.

[CW-HAL9000]

I have experienced burning on hard woods. I have also experienced it when my bit needs cleaning or sharpening.

[lvwood1212]

cutting ash, maple, red oak, white oak, butch, walnut haven had any problem with burning in center line text. most carving have been best and on the walnut used optimal. like using optimal give better finish also use best in carving.

[FWMiller]

Which software version are you using? I've been using a brand new CMT 60 degree V bit and have noticed some light burning in poplar and birch plywood when cutting centerline text. I noticed it happens where the bit drops down and pauses before moving or pauses before being lifted up. I'm using version 1.187 of designer and the machine's bit movements during centerline carving appear to be a bit clumsy or awkward at times for lack of a better description. I've also had some where it cut very nicely so there must be some types of text that give it more difficulty. I'm curious if the reported improvements in centerline for 2.0 make for smoother bit movements which would reduce the chance of burning.

[lvwood1212]

have 2.004 software and I don't use plywood because the amount of glue in the wood would cause burning at that point on the up and down where the program seems to slow down. never had any burning but don't use plywood have used poplar with no problem. what depth do you carve? have used 60 degree bit and 1/16 taper bit for centerline test . have cut up to .150 and as low as .010 with the 60 degree bit. works best around for me at .063 . some lettering don't seem to cut the as good as others.

[Digitalwoodshop]

Mechanical of the machine can cause burning too... As in the bit flopping around as cutting.... Loose Roller Rail Bearing, bad Y Gearbox Bearing. If you grab your Z truck and pull and push in all directions looking for something loose...

AL

[Underdog]

I'm using a 90 degree bit that's been used very little. The machine only has a few hours on it, though it's been shipped a couple of times. I was cutting some white maple, and the bit just seems to dwell too long in spots. I think I was using the font "Georgia" with the default depth which, I think is .250" deep. Using the old version (1.87?) of Designer.

On a side note, I'm a bit disappointed in the uneven nature of the centerline cuts. Seems to me the edges of those cuts should be smooth like the lines of the font, and not bumpy like someone joggled your arm while you're writing....

[FWMiller]

I am also disappointed with the carve quality of centerline. I was expecting much smoother lines. It's almost like the bit is following a pixelated version of the font. I've read that the new 2.0 version of designer has "better" centerline algorithms. I'd like to hear from someone whether or not the improvements include smoothing out the cuts. Some fonts are not as bad, but it's kind of boring to use square fonts.

[Digitalwoodshop]

Sounds to me like you have a mechanical problem with your machine....

Make a project and assign the V90 bit to a few circles and rectangles and set the depth to less than a 1/4 inch as vector cuts... See what the machine does.... Does the Circle come out normal or wavy...

Inspect the edge of the V90... I dip them in Alcohol to clean them off....

AL

[DickB]

I agree with Al. My centerline cuts are smooth.

[FWMiller]

I've done a lot of vector carves and they are very smooth. I've even done vector carves and centerline in the same carve and the vectors look great. I wonder if there are artifacts in specific fonts that are causing it. Sounds like I need to run some experiments on various fonts and see if it's actually the fonts themselves. I'm just using the standard fonts that come with my Windows and MS office.

[Underdog]

So if I have a mechanical problem, where is the most likely failure on the machine?

[peep]

Interesting. I normally always get burn marks, too

[cnsranch]

Underdog - is there any way you can post an MPC of a project you had trouble with, and a pic of the finished project itself??

A dull bit will burn - I use a diamond sharpening block from HarborFreight to dress up my V bits.

If you're carving a vector that has a "stepped" diagonal or round cut, WYSIWYG - it will carve just like Designer shows it will cut. If, however, you're carving text from a font in your computer, it should carve perfectly fine, with some exceptions - there are just some fonts that don't carve well - you need to look at them closely in Designer to make sure they'll be OK.

[Underdog]

I'll try to remember to post the MPC file tonight, and get a close up pic of the font. Some parts of the font look crisp, and some parts of the font look like something wobbled. I've already painted it, so I won't have pix of the burn marks.

[Underdog]

Here's the MPC file.

[Ton80]

If you can carve smooth vector lines created with the drawing tools but get the more jagged vectors with fonts then it's probably the font. I don't know what causes it myself because the font will print smooth and if blown up in a graphic app you don't see all that jaggedness the CW will produce. You will actually see this in designer before you ever run the carve so you have a chance to see the issue before the bit bits the wood. Changing fonts until you find one that shows smooth lines in designer would be my advice. As far as the burning it is probably the bit needs to be touched up and cleaned. If it's brand new then it could be the wood, too deep a v carve on a bold font or trouble with the machine. Some woods are always prone to burn with v carves and the CW because you have no control of the RPM rate and the feed rate but you're at the mercy of the machine/software which doesn't always play nice with a wood like maple.

[atcltd]

Considerably better with new SW, the Dremel with a flap sander is still your best friend. Try sanding with the Scotch-Brite Radial Bristle disks on the Dremel. They do a good job of cleaning out text (Available from www.traditionalwoodworker.com)

[carrothers]

I've had centerline "burning" and attribute it to dull bits. cleaning them helps. also I noticed that some fonts are very sensitive to proportions.. if I unlock and stretch one dimension I get a slighly distored font which a makes the bit stay in one place too long.