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V-carve inlay clamping times

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Forum topic by Chris15 posted 08-29-2018 12:36 PM 1454 views 0 times favorited 14 replies Add to Favorites Watch
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Chris15

2 posts in 299 days


08-29-2018 12:36 PM

I’ve been making cutting boards with inlays using a shapeoko 3 and v-carve software. I have a 12 ton press that I use to clamp the inlay into the pocket with Titebond 3, then let it sit overnight for about 12 hours in the press.

Two weeks after finishing, I noticed a corner of the inlay popped up a little bit from the pocket.

It’s a maple into walnut inlay, if that matters. Both the inlay and the pocket were both end grain. .3” pocket, inlay is .1” start depth and .2” flat depth

Anyone familiar with this stuff care to chime in with some tips/tricks for what works for them?

Thank you!


14 replies so far

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John Smith

1834 posts in 556 days


#1 posted 08-29-2018 01:29 PM

I would think that you are cutting off the air needed for the glue to “dry”
plus – too much pressure that squeezes most of the glue out from the mating surfaces.
are you using a barrier between the press and the wood – such as plastic or wax paper ??

.

.

-- Failure is proof that you at least tried ~ now, go do it again, and again, until you get it right --

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GR8HUNTER

6106 posts in 1106 days


#2 posted 08-29-2018 02:38 PM



I would think that you are cutting off the air needed for the glue to “dry”
plus – too much pressure that squeezes most of the glue out from the mating surfaces.
are you using a barrier between the press and the wood – such as plastic or wax paper ??

.

.

- John Smith


+1 :<))

-- Tony---- Reinholds,Pa.------ REMEMBER TO ALWAYS HAVE FUN

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Chris15

2 posts in 299 days


#3 posted 08-29-2018 05:20 PM

There’s a .1” distance between the pocket surface and the bottom of the inlay for glue, so it shouldn’t be squeezing out all of the glue.

How do you do inlays?

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John Smith

1834 posts in 556 days


#4 posted 08-29-2018 06:28 PM

I guess I am “assuming” you are applying most of the full 12 tons of pressure with your press ?
could you post some photos of the issues you are experiencing ?
you are mentioning “V” Carve . . . it just seems unnatural for a flat inlay into a V-groove.
especially on a cutting board that is exposed to frequent washings.

.

.

-- Failure is proof that you at least tried ~ now, go do it again, and again, until you get it right --

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JAAune

1864 posts in 2710 days


#5 posted 08-29-2018 07:10 PM

End grain soaks up glue pretty fast. It’s possible the 12ton press clamped all the glue out (despite the .01” gap) then the end grain wicked the rest of the glue away from the surface.

On end grain, I’ll do 2 or more applications of glue until it stops disappearing into the wood then clamp it.

The other possibility is that the .01” gap is still there but there’s no glue in some places due to wicking. Multiple applications of glue would help with this too.

-- See my work at http://remmertstudios.com and http://altaredesign.com

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John Smith

1834 posts in 556 days


#6 posted 08-29-2018 08:18 PM

I can’t speak for the general populous, but, for the people that I know personally
that do inlays, the inlay fits “snuggly” in the cavity that has square carved sides and bottoms
like the attached drawing. if you are using a router bit that is not square and then
installing the inlay that also is not a good fit, I would expect to see adhesive issues.
a good fitting inlay should press firmly into place and stay there by itself without pressure.
after the prescribed drying time for the adhesive, it is sanded flush with the surface
and finished accordingly. (that is the way I understand the procedure of inlays).

.

-- Failure is proof that you at least tried ~ now, go do it again, and again, until you get it right --

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JeramieG

3 posts in 944 days


#7 posted 08-29-2018 08:47 PM

I use v-carve to do inlays and use method in this video if this link did not work search vcarve inlay on youtube its the one with rocket, butterfly, and frog. You use same v bit for both parts I have had success with this method using normal clamps with out excessive pressure. I believe this is the method you are using which leaves .1 gap between parts when you glue them which you cut apart with band saw when glue dries, if you are using 12 ton press you may be closing gap inside inlay and squeezing out all of the glue causing your problem.

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ArtMann

1385 posts in 1210 days


#8 posted 08-30-2018 05:14 PM

You are using far too much clamping pressure if you are applying anything like 12 tons. What you are doing is compressing the actual wood fiber. When the pressure is released, the wood assumes its previous shape. I have had the same problem using a 2.5 ton car jack and an overhead beam in my shop to apply the pressure. I have also switched to thickened epoxy, rather than PVA glue, to hold the inlay in place. It doesn’t shrink as it cures.

For those of you who are not familiar with the CNC vcarve inlay technique should read up on it before giving too much advice. It isn’t like a hand cut inlay. The shoulders of the inlay are not square and the inlay doesn’t touch the bottom of the female cut by design.

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John Smith

1834 posts in 556 days


#9 posted 08-30-2018 07:44 PM

Art. I watched a few of the V-Carve videos on youtube and although it is a
very neat way of doing inlays, I just feel there may be something missing
when it comes to doing inlays in cutting boards that are continually going
through the dry – wet – dry – wet cycles on a regular basis.
even though the Titebond III is waterproof, something is going amiss to
cause delaminations. . . . perhaps the epoxy will hold up better in the long run.
plus – just spring clamps should be used vs tons of pressure. . . . the jury is still out.

-- Failure is proof that you at least tried ~ now, go do it again, and again, until you get it right --

View Steve Peterson's profile (online now)

Steve Peterson

405 posts in 3476 days


#10 posted 08-30-2018 11:22 PM

I believe that the video uses “V” bits to cut both halves of the inlay. This leaves sloped sides so the inlay segment can be pushed tight against the sides. It seems great except for the small air gap that is left to allow a tight fit. Otherwise, a small amount of sawdust or fuzzies would prevent the inlay from seating all the way. A 0.1” air gap just below the surface of an end grain cutting board does not seem like an ideal situation. Any inlay segment larger than 1” across seems like it could crack with a small amount of pressure.

I prefer John’s inlay picture with straight sides. It requires proper tuning to get a tight fit. The inlay might need an offset of a few thousandths in either direction for a perfect fit. It only takes a few minutes to figure it out. The benefit is that the sides and bottom surfaces are all glued surfaces.

-- Steve

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ArtMann

1385 posts in 1210 days


#11 posted 08-31-2018 03:48 AM

Steve, you are absolutely right. There is a problem with leaving a partially filled gap between the inlay and substrate. On large inlays, the middle can develop a concave shape as PVA glue dries and shrinks. That is why I now only use thickened epoxy. here is an example of a design with which I originally had a problem.

I have done CNC routed inlays like John illustrated but there is a small but noticeable gap in places between the substrate and the inlay. There is also the problem of rounded inside corners due to bit diameter. Using the Vcarve technique, the fit and appearance is as good to me as what an expert craftsman can do. The inlay is wedged into the pocket at an angle that closes the gaps 100%. Here is an example of a box that I have made a quite a few times for various customers.

View Kazooman's profile

Kazooman

1318 posts in 2346 days


#12 posted 08-31-2018 05:35 AM

I watched the video and learned about a technique I knew very little about. I would have to agree with the several posts that were concerned about the inlay going concave across a wide section or being fragile in use. A 0.1” gap is huge,

However, the thing that intrigued me was that this is a really good way to do an inlay with end grain (if such a need should ever arise). Having the inlay portion mounted on a backer would give it enough strength to survive falling apart before the glue up.

Having said that, as a hobbyist woodworker, and not someone trying to mass produce pieces for sale, at a profit, this is not something that I would ever be interested in doing. I can almost hear the groans and sighs from the hand plane crowd when they see the state of the art in woodworking. Programming a machine to cut two profiles that I glue together to make a decorative inlay just doesn’t seem like craftsmanship. You can probably skip the programming step and just buy a program to feed into your CNC machine. The craftsmen who spend countless hours refining each piece of their marquetry will have to find another pastime.

I guess that this is just the next step in the evolution of woodworking. There are the “purist hand tool believers”, the “power tools are OK, I still do the set up, cutting, machining of profiles, etc., by myself, with some hand work” group, and the future of the “I wrote the program that directed the CNC machine to produce exactly what I wanted” group.

Chacon a son gout!

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Underdog

1334 posts in 2429 days


#13 posted 08-31-2018 12:48 PM

Never fear Kazooman.

Hand work is alive and well. There are folks who still enjoy handwork and willing to do it. In fact there are those discriminating people who are willing to pay big bucks for quality handwork.

As long as that’s the case, quality handwork will never be a “lost art” no matter how well a CNC can do the work.

I’m saying this being a fan of both good quality handwork, and well designed and executed CNC work. I’m not a fan of badly executed work of either…

-- Jim, Georgia, USA

View ArtMann's profile

ArtMann

1385 posts in 1210 days


#14 posted 08-31-2018 02:11 PM

The designs I carve are done by my wife, who is a commercial artist and graphic designer. I don’t think there will ever be a time when machines or computers can be an adequate substitute for human creativity, regardless of fabrication methods.

I admire people like Tatiana, (aka “Fancychip”) who can do such beautiful carvings by hand. However, very few people could afford her work if she is paid what she deserves. I can do custom stuff that looks fairly good and sell it at a price that most people can afford. That takes more than just an expensive woodworking machine.

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