Wood Engraving Challenges

[Josh Beckmann]

Hello,
I'm having some difficulty with engraving signs. I'm getting some tear out and overall lower quality cuts than I'd like. Any veterans have suggestions?

Thanks a lot!
Josh

[barrowj]

Josh,

Please post the running parameters of the job, move speed, etc.

Joe

[scottp55]

Josh,
If that notation is 3.0 IPS? Then you may want to slow down your Feed.
Always a problem with things like the tips of the W, maybe try a similar font without the sharp,narrow points? OR convert to curves if it's a one time and soften the tips in Node edit? (Easier to find a similar font)
What bits and pass depths were you running? May want to remeasure your EndMill Diameter...Should be cutting Exactly to your VBit cut.
Not VCarving it with a flat depth? It would give you Crisp outside corners.
Species makes a huge difference also, have you tried other species with the same results?
Is bit Sharp?
Looked for some close-up pics, but they're all on my other computer and only examples of VCarving with a clearance tool with a deeper depth are these from inlays using an Onsrud engraving and Centurion FEM .25"downcut. On the Maple the material was lifting off the carpet tape and you can see top left action that resulted.
Any chance material is lifting/moving or any "slop" when machine is powered up and you try to move the router/spindle? Which do you have, and which machine/year?
I always think I cut too slow, but the bit stays cool and I get good results I think.
All these were cut in the 1 to 1.4 IPS range with RPM to keep bit cool and good chips---Again I'm very conservative on pass depth and generally stick to 1/2 diameter passes.
Quite often I'll run the outline first at the slow speed, Then the clearance tool faster, to make sure I don't rip anything out.
Hope any of this helped.
Wish I had more pertinent pics, but too lazy to fire up old computer
scott

[David Iannone]

Hi Josh,
Any update with the material you are cutting and what bit and how fast?

This forum is here to help.

Dave

[Josh Beckmann]

Hi Folks, Thanks for your generous responses. And, sorry for the delay. I got sick and then really busy! I am mostly looking to create single sided bevels in pocketed reliefs using a v-cutter. This particular piece isn’t so important to me as is learning the approach.

1. What feeds and speeds do you recommend for general engraving in solid wood?
2. How many passes should I take?
3. Do you get better results with smaller tip bits or wider bits?
4. Would you pocket an area before you create the bevel or the other way around?
5. Can you recommend any of the bits I have for this type of work or other bits? I have:
   
   1. Many of these types with different size tips: http://www.zoro.com/i/G2814777/
   2. http://www.toolstoday.com/p-4926-v-g...eywords=180-18
   3. http://www.toolstoday.com/p-4926-v-g...eywords=180-10
   4. http://www.toolstoday.com/p-4926-v-g...keywords=45705
   
   
6. Scott, what do you mean by “May want to remeasure your EndMill Diameter...Should be cutting Exactly to your VBit cut.” ?
7. I have tried maple with better luck. See 2nd photo. What species do you recommend?

[barrowj]

Josh,

I too had similar results on several of my attempts until I made several adjustments. Different species of wood cut differently and the area left after cutting is as important as the cut. I sweetgum, I cut a design that left a thin strip between different pockets and it tore out the strip, I made that strip slightly wider and slowed down the bot and it came out great. Maple reacted better as do most tight grained woods. Try slowing the move cut to between 1.5 - 2 ips and keep you speed around 12k-14k depending on the bit, you can play with these on a test piece by just making lines or arcs to see what works best.

Keep trying and you will nail down the right router/spindle speed and move speed. Please keep us posted with pics and speeds.

Joe

[scottp55]

Josh,
#'s 1 and 2 really depend on a LOT of things. For instance your first bit only has 1 cutting face so rpm's will have to be higher/or feed slower than your 2 flutes.
#3 depends on what your flat depth is to some extent. Generally a wider bit and shank are better as one pass eliminates "waterlines", But if you're only carving a shallow cut for everything..then that's a lot of carbide you're paying for and Not using. I'm kinda specialized on tiny stuff at the moment, with most flat depths less than .1", so I find a solid carbide 1/8" is doing what I need cutting some fairly bit dulling woods and prefer as sharp a bit as I can use--so swapping out bits is less painful and cuts are better--Just my preference as I'm only using the tips.

#4 I personally prefer to cut the outlines first and Then clear.
#5 Any of those bits should be fine, but your Onsrud has a Large flat that will affect the inside corner crispness and should be entered in your database as an engraving bit with the correct flat size so your previews are accurate. IF you can get away with 1/4" shanks then I'm finding I prefer solid carbide bits/ 1/2's have less vibration but too rich for my blood and needs at the moment.
#6 I thought I saw your clearance tool cutting into the Vbit toolpath, But noticed other spots it didn't quite reach? May be material moving as there seems to be other stuff going on. A lot of bits aren't the exact size sold as, and you want to measure Diameter exactly so Vectric can adjust so clearance and VBit paths meet exactly.
#7 Maple is much better and capable of handling fine detail. If only it weren't for the "Fuzzies" (run toolpath twice works Very well on Fuzzies(Thanks Bob E))
Try Cherry BUT there are lots of others and everybody has their favorites.
If you ever want talk and play with a smaller machine, I'm only an hour and a half North and you'd be welcome for a day/hour If you bring your own material/bit/files we could "Dial" them in.
What machine and how old?
scott

[Josh Beckmann]

Hi Scott,
Thanks a lot for your suggestions. There's so much to consider, it's sometimes hard to know exactly where to start. In this case the project is pretty open with wood types and approaches, but I'm hoping to find a more generalizable process so that folks can more easily choose their own designs. How does next weekend look for you for a trip up to your neighborhood? Another weekend would work just fine as well. Would love a second set of eyes.

Best,
Josh

[scottp55]

Josh,
You have PM.

[scottp55]

Josh,
E-mail me from contact list, Lousy at PM'ing and mailbox getting full.