Blow out

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Craig Thompson
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Blow out

Post by Craig Thompson »

Hello all, I have been having problems v carving letters. It seems every time I try to do it, I get blow out on the letters, I'm using a 45 degree insert bit running at 18000 rpm and 80 inch per minute. I have tried different species of wood, and have the same problem. I have attached a photo showing the problem. Any suggestions would be greatly appreciated.
Thanks
Craig
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Blow out carving letters
Blow out carving letters

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dwilli9013
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Re: Blow out

Post by dwilli9013 »

Craig Thompson wrote:Hello all, I have been having problems v carving letters. It seems every time I try to do it, I get blow out on the letters, I'm using a 45 degree insert bit running at 18000 rpm and 80 inch per minute. I have tried different species of wood, and have the same problem. I have attached a photo showing the problem. Any suggestions would be greatly appreciated.
Thanks
Craig
Trying setting your flat depth on your v bit to .125 and slow it down a bit.
D-Dub
Dwayne
Dwilli

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highpockets
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Re: Blow out

Post by highpockets »

What Dwayne said. Plus use a sharp bit, slow the feed rate. Especially on softer woods and woods that are prone to breakout, finish the surface prior to V-carving. Including several coats of Shellac or Lacquer, this will help strengthen the wood.
John
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Xxray
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Re: Blow out

Post by Xxray »

Can't gauge the size of fonts, might also have better luck using a dedicated engraving bit if its pretty small
Doug

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martin54
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Re: Blow out

Post by martin54 »

As has already been said 80 ipm for cutting delicate text is way to fast, try slowing your feed rates down until you are happy with the results, what works best for you may be very different from what works for others depending on machine, cutter, text size etc etc.
Only real way is to experiment a bit yourself. The other thing that can help is to change the depth of cut for the particular bit you are using, a shallower cut can sometimes make a big difference but comes at the expense of the time taken to complete. :lol: :lol:

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Mark's Wood Chips
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Re: Blow out

Post by Mark's Wood Chips »

Like Highpockets said, use a sharp bit. I have found, the hard way, that using a quality bit makes a world of difference in the quality of the cut.

Mark

Beltramidave
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Re: Blow out

Post by Beltramidave »

Trying setting your flat depth on your v bit to .125 and slow it down a bit.[/quote]

Wouldn't setting a flat depth defeat the purpose of using a Vcarve toolpath? Wouldn't you lose the crispness in the lettering?
Dave
https://lakesedgewoodcraft.com/

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highpockets
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Re: Blow out

Post by highpockets »

dah79 wrote:Trying setting your flat depth on your v bit to .125 and slow it down a bit.
Wouldn't setting a flat depth defeat the purpose of using a Vcarve toolpath? Wouldn't you lose the crispness in the lettering?[/quote]

Not really, the edges will still be crisp, only the bottom of the vcut will suffer a bit and that depends on the stepover you set.
John
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Craig Thompson
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Re: Blow out

Post by Craig Thompson »

I re-carved the plaque with your help. I sprayed 3 coats of lacquer sealer then tuned the speed down to 50 ipm. It came out awesome. Thank you for your help. I attached the
Complete cut
Complete cut
project I just finished, It's for my 6 year old grand daughters door. Not sure if the wife is going to paint it or just stain it. Its wonderful to have a place to go when your at your wits end. Again Thank you
Craig :D :D
Before all your help
Before all your help
After your help
After your help

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highpockets
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Re: Blow out

Post by highpockets »

Much better. If you decide to color the v-carving apply a couple more coats of Lacquer or Shellac to seal the end grain exposed by the v-carving. This will help prevent bleeding.
John
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dwilli9013
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Re: Blow out

Post by dwilli9013 »

Looks awesome.
That particular carving would also look incredible using Michael M. technique of filling the lines with different color crayola crayons.
Thanks for sharing. Always good to see the work when it all works out. :D :D :D
D-Dub
Dwayne
Dwilli

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