Chip out using V Carve

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Harleyretired
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Chip out using V Carve

Post by Harleyretired »

I am getting chip out on my project. I am using a 22 deg vbit would changing to a 45 help and slowing down my feed rate?

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Rcnewcomb
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Re: Chip out using V Carve

Post by Rcnewcomb »

What material are you carving?
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scottp55
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Re: Chip out using V Carve

Post by scottp55 »

A picture of the actual wood fairly close up, and a snapshot of the tool settings in the toolpath (Edit) would help tremendously as well.
Pics may have to be resized to be accepted, but make sure they are large enough to read and show the details.
Simply swapping to a different angle bit will generally not solve the underlying issue.
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Harleyretired
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Re: Chip out using V Carve

Post by Harleyretired »

]I am using Ash but it has happened with other wood before. Not sure how to download photos.
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Harleyretired
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Re: Chip out using V Carve

Post by Harleyretired »

Here is my settings feed rate 35 and plunge rate 25

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Re: Chip out using V Carve

Post by Bob Reda »

A lot of chip out can happen when cutting against the grain. Also, it might be the starting of a dull bit.

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Re: Chip out using V Carve

Post by newmexico »

Yes, that darn "Chip Out" can ruin your piece. It's going to happen with almost any wood.

Here's our solution:

Bit: V90
Depth Of Cut: 0.075 (almost engraving at that shallow depth)
Feed Rate: 60 ipm
Router RPM's: 12k

However, the best solution is to go back to your CAD program and remove all that detail. Get rid of any path that is too close to another path.
When we cut a path in wood, we are weakening the paths too close to each other.

This problem is compounded when cutting too deep with small fonts. The inside of your A's and O's and B's can blow out.

Hope that makes sense.

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Re: Chip out using V Carve

Post by martin54 »

how did you create the vectors? Looks like it might be a bitmap trace from the raggy edges although they may be caused by flex in the machine. 2 settings you have missed that are important are rpm & the depth of cut for the v bit, you may be trying to cut to deeply with each pass :lol: :lol:

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Re: Chip out using V Carve

Post by Leo »

One BIG reason Pine is not so good is because it chips out like so easily.

Maple, Cherry, Walnut is MUCH better.
Really tight grained woods.

OOPS - I just noticed ASH.

Still - Oak ans ASH DO chipout easily

Also really small stuff is really hard to not chipout. Can be done - but not easily.

The areas you are pointing to are in fact really tiny - not very strong
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Re: Chip out using V Carve

Post by Jim_in_PA »

Leo is correct that it's relatively easy to get chip-out on a species like ash and oak (as well as pine) because of the nature of the grain pattern. Not having a sharp tool can contribute to that, of course, but the nature of the wood, itself, can be an issue for what you are experiencing. You could try it with a shallower flat depth to see if that helps.

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Re: Chip out using V Carve

Post by WNC_Ed »

Not specific to this situation but just a general question, would applying a sanding sealer or similar before the operation give any strength to the wood fibers helping to reduce chip out?
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Re: Chip out using V Carve

Post by martin54 »

WNC_Ed wrote:Not specific to this situation but just a general question, would applying a sanding sealer or similar before the operation give any strength to the wood fibers helping to reduce chip out?

Yes it can do, something I quite often do when carving fine detail, think Scott does it as well :lol: :lol: :lol:

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Re: Chip out using V Carve

Post by TReischl »

WNC_Ed wrote:Not specific to this situation but just a general question, would applying a sanding sealer or similar before the operation give any strength to the wood fibers helping to reduce chip out?
Yes, it can, to a point. It is an old hand carver's technique. The most popular method is to use thinned out shellac. The real trick is wait long enough for the shellac to become fully hard. Depending on the species the shellac may only penetrate .005 to .010.

Now, don't shoot me, but using a really sharp bit can help a lot too. Expensive carbide micrograin bits can be pretty sharp, but the simple fact is that HSS can be sharper. For a good discussion:

http://www.woodweb.com/knowledge_base/S ... rbide.html

Carbide has all sorts of neat advantages, but sometimes it is just not the right material for the job.

I have a small mill that I use manually. There is a huge difference in how that machine cuts aluminum with HSS v Carbide tooling. The HSS yields much smoother cuts.

One of the nice things about HSS is that it is easy to hone the edges on cutting tools without having to use diamonds.
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Re: Chip out using V Carve

Post by Harleyretired »

Well I did the project again. But this time I put the feed and plunge rates at 20. I used a 45 vbit at a depth of .04 and the router speed I slowed it down. I carved 3 items and I ended up with one very small chip out.

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Re: Chip out using V Carve

Post by Leo »

TReischl wrote:
WNC_Ed wrote:Not specific to this situation but just a general question, would applying a sanding sealer or similar before the operation give any strength to the wood fibers helping to reduce chip out?
Yes, it can, to a point. It is an old hand carver's technique. The most popular method is to use thinned out shellac. The real trick is wait long enough for the shellac to become fully hard. Depending on the species the shellac may only penetrate .005 to .010.

Now, don't shoot me, but using a really sharp bit can help a lot too. Expensive carbide micrograin bits can be pretty sharp, but the simple fact is that HSS can be sharper. For a good discussion:

http://www.woodweb.com/knowledge_base/S ... rbide.html

Carbide has all sorts of neat advantages, but sometimes it is just not the right material for the job.

I have a small mill that I use manually. There is a huge difference in how that machine cuts aluminum with HSS v Carbide tooling. The HSS yields much smoother cuts.

One of the nice things about HSS is that it is easy to hone the edges on cutting tools without having to use diamonds.

Agreed - BUT - keep in mind that HSS generally needs to run at slower RPMs than carbide. HSS cannot tolerate head generated from high RPMs as carbide can. Therefore chipload becomes even more important.
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