Lettering

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Neal Meyers Jr
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Lettering

Post by Neal Meyers Jr »

What I need is advice on letter cutting. What speeds to run to try and minimize tear out and chipping of the letters. I am using a 90* v cutter 1/8 inch deep and I am cutting Poplar.

I need any advise on what speed to run that will not cause burning but not tear out the areas like those where the lines of an "N" or "A"s cross. I have thought about cutting the letters with a very narrow veining cutter and then re-cutting with the 90*. Sorta like scoring then final cutting. Thank you
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Rcnewcomb
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Re: Lettering

Post by Rcnewcomb »

Try a CMT 815.660.11 bit at 14K-16K RPM at about 150 to 200 ips
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JamesB
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Re: Lettering

Post by JamesB »

I would guess Randall means 150-200 IPM (inches per minute) for his recommendation rather than IPS.

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Adrian
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Re: Lettering

Post by Adrian »

I always use three flute/edges V-Bits when VCarving. Excellent results everytime with no chipping even in coarse grained woods.

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Re: Lettering

Post by Neal Meyers Jr »

Three edge v bits never seen them....who is your source?
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Mike-S
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Re: Lettering

Post by Mike-S »

These are great--get 1/2" shaft if you have that collet.
http://www.amazon.com/CMT-858-501-11-Cu ... B000P4JOOY

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Re: Lettering

Post by PaulRowntree »

Neal Meyers Jr wrote:Three edge v bits never seen them....who is your source?
Lee Valley has one

http://www.leevalley.com/US/Wood/page.a ... 46175&ap=1
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Adrian
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Re: Lettering

Post by Adrian »

Neal Meyers Jr wrote:Three edge v bits never seen them....who is your source?
I buy them from a company in the UK (Wealden Tools). They don't ship to the US though.

If you're in the UK or Europe here's the link - http://www.wealdentool.com/acatalog/Onl ... e_718.html and http://www.wealdentool.com/acatalog/Onl ... e_719.html

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Re: Lettering

Post by martin54 »

I use the same bits Adrian does purchased from the same place, have the 2 flute v bits they sell as well but can't remember the last time either of the 2 flute bits were out the plastic tube they come in lol.

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Re: Lettering

Post by glenninvb »

Just cut this a little while ago, the bouy is 3.5" tall
As some of you probably know, I love those 1/2 round bits for small stuff (one I used had .005 tip, cut depth .010)
They are pretty good for small text or engraving
Sealed maple cuts nice anyway.

I've been using 2 flute 60 or 90 for Vcarve but I'll order some 3 flute to try, thanks
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Re: Lettering

Post by rscrawford »

I also prefer the 3 flute v-bits, with 1/2" shank. Those seem to give me the least tearout. I like the 1/2" shaft because it seems less prone to chatter.

This is the absolute best 60 degree v-bit I've used for fine detail work in any type of wood. Expensive, but once you use it you won't be able to go back to cheaper ones :D

It also makes a difference what collets and spindle/router you have. For fine detail work, any runout in your router or your collets will give more chance of tearout - it causes chatter.

http://www.toolstoday.com/p-5162-sign-m ... -bits.aspx
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Re: Lettering

Post by MalcolmLKoch »

I concluded that chipping is only a smaller version of tear-out. I have a box cutting jig (Incra) and did as they suggested and used a backer board to prevent tear out. In just doing a cut on a table saw, I've used blue painter's tape on the on all four sides of the cut. I rub it into the wood or use a wooden roller to enhance adhesion. Remove the tape and you'll find a minimum of tear out.

Today I started a final cut on a plaque that folks on the forum have been providing assistance. There was a lot of tear out and I rather imagine that is because I used a sticky-back veneer of walnut over mahogany. A glued veneer I don't think would have done that. The picture of the grizzly bear (vectric 3D art) had pronounced tear out; but, I didn't follow my own advice.

So when I started with the lettering and some lines, I covered the entire surface with the blue painter's tape. So far the lines do not see any tear out. We'll see about the vCarve bit tomorrow and I'll post a picture. I've also presanded to 600 grit and then put on a couple of coats of Deft Sanding Sealer. Another thing I noticed is that the bit gathered wood material at the top of the bit without blue tape. Presumably the sticky stuff from the veneer is preventing the bit from clearing. However, with blue tape there is none of that. This, I believe, is because of the nature of the glue. The veneer glue is a super high adhesion permanent non repositioning stuff while the blue tape is repositionable which is very handy to be able to peel back the tape to use the Z Touch Plate during bit changes.

The store where I get tooling bits always recommends three and four flute bits and from what I can tell they're right. Cleaner cuts.

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Re: Lettering

Post by MalcolmLKoch »

My source for 3 and four flute bits is in the United States. I have two sources: Tool Supply in Tualatin, Oregon. The other is Amana Tool; but you have to go to their web site and find a dealer near you and order through the dealer. They do not ship direct to customers except through a dealer. Prices for the same bit can vary from dealer to dealer.

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Re: Lettering

Post by Leo »

They come in 1/4 shank also

http://www.amazon.com/CMT-858-001-11-de ... +point+bit

I am going to give these a try also. I am currently using 2 flute bits and not really having trouble - EXCEPT - on really small lettering.

Size matters - really small text is much harder to do. Also Poplar is not a bad wood to use - but also not the best. Maple may be a better choice as it is stronger and holds together better.
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Re: Lettering

Post by MalcolmLKoch »

Well. Nuts. I tried the Black Walnut sticky-back veneer on a substrate of mahogany. Stuck with the vCarve bits for all the lettering. It is true that the smaller the lettering the more difficult it is to mill. Lettering doesn't hold up. It is necessary to increase letterspacing even more before converting to curves and then some of the curves need some adjustment particularly to provide a greater base for the finer parts of the letter so that the wood doesn't bust out.

I don't think the mahogany is all that great to work with. I wanted it because of the coppery color I could get out of the medallion of a grizzly downloaded from the vectric CAD art site.

What is happening to the veneer is a lot of shredding of fibers, very sticky because of the sticky-back adhesive. I think consideration might be given to using some Pentacryl on the base, curing it, and then use a thicker veneer; but, adhere with a two part epoxy.

Changed my mind on uploading pix. Want to get it right to show before and after. Might feel ready then for a different sort of discussion. Want to see how to do a post on a collaborative project titled, "Cow Pie". Think of the nursery rhyme "Four and Twenty Blackbirds Baked in a Pie" only milling a pie bottom and a pie top to look like an apple pie top and inside what amounts to a bowl with a lid is a small herd of cnc'd cows. Only the cows will be a little anatomically different (udders up front for a good laugh). (Has to do with a dairy my uncle owned and something a bit unusual in the way of a billboard).

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