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Light Cured Resin for building up nut slots
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Author:  Barry Daniels [ Sun Oct 29, 2017 9:12 am ]
Post subject:  Light Cured Resin for building up nut slots

Is anyone here geared up to do light cured resin to buildup nut slots, and care to share some techniques and material list? I have been looking at battery operated dental UV curing lights on eBay and thinking this would be a fairly inexpensive way to do this.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR10.TRC2.A0.H0.Xlight+cure+dental+light.TRS0&_nkw=light+cure+dental+light&_sacat=0

Author:  Hesh [ Sun Oct 29, 2017 9:32 am ]
Post subject:  Re: Light Cured Resin for building up nut slots

Hey Barry:

We use light cured composite dental fillings, not the same thing as resin I believe, every day. It's wonderful and makes life much more enjoyable when one cuts a nut slot too low. It also provides clients with the value of a filled nut slot that will actually stay that way unlike with dust and CA.

We believe these dental filling when cured to be harder than a bone nut. I've successfully filled bone, horn, plastic, tusk, corian, and even ebony. We have a plethora of colors available too so that we can fill that nut for the J. Giles song reference of Goober Gober with the green teeth.... :mrgreen: :D

Three step process with dental fillings. Acid etch (I often skip this step...), bonding agent light cured for 20 seconds and then the composite filling material light cured for 40 seconds. Prior to all of this I clean up the slot with files and file with my .013" file a little mechanical dovetail for added insurance.

Author:  Barry Daniels [ Sun Oct 29, 2017 9:58 am ]
Post subject:  Re: Light Cured Resin for building up nut slots

Can you do this on an attached nut or do you have to remove it from the neck?

Author:  david farmer [ Sun Oct 29, 2017 2:32 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

Barry Daniels wrote:
Can you do this on an attached nut or do you have to remove it from the neck?



Attached is part of the beauty.

Dentists have to dump out dated composite long before it's bad. Use your rolodex to find a dentist you have a connection with. I have a friend who's happy not to throw it all away.

I'm pretty new to it but it's hard to imagine it won't be the new standard of care for many situations.

Author:  SteveSmith [ Sun Oct 29, 2017 4:43 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

I just picked up a unit with a small amount of the binding agent and some small packages of the composite filler (both expired of course). Have not needed to try it out yet but looking forward to it.

Author:  DannyV [ Sun Oct 29, 2017 4:45 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

How did y'all come by the uv unit? I believe that is what is needed for curing? Should I be checking local dentists dumpsters regularly?

Author:  Barry Daniels [ Sun Oct 29, 2017 5:18 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

Did you see the link in the first post? Curing lights on eBay for around $20.

Author:  SteveSmith [ Sun Oct 29, 2017 5:39 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

Got mine from a dentist on another forum

Author:  dpetrzelka [ Sun Oct 29, 2017 9:27 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

I just asked my kid's dentist - they have to retire the UV units occasionally as well. Two months later they called with an old unit ready for pick up.

I do need to work on finding a few different colors of filling medium to match various color bone.

Author:  Hesh [ Sun Oct 29, 2017 11:14 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

Barry Daniels wrote:
Can you do this on an attached nut or do you have to remove it from the neck?


Why on the guitar of course which is helpful in then cutting the nut slots back to the low cut that we do. Strings remain on too. You can tape on either side of the nut but I don't. I'm just precise using a .010" string to put the bonding agent and later the composite dental fill in the slots. If I get any on the nut top I just swipe it away and wipe it on my pants..... My pants never seem to get cavities now....;)

It likely takes me under 5 minutes to fill a slot which is done because instruments come in with low slots as you know and at times I go too far getting those low slots. When moving all day between various nut materials, bone, plastic, etc some nuts are way softer than others. Taylor's nuts are pretty soft, G*bson too in my experience. OTOH a $200 Recording King from China has a real bone nut.... Go figure.

Author:  Hesh [ Sun Oct 29, 2017 11:15 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

david farmer wrote:
Barry Daniels wrote:
Can you do this on an attached nut or do you have to remove it from the neck?



Attached is part of the beauty.

Dentists have to dump out dated composite long before it's bad. Use your rolodex to find a dentist you have a connection with. I have a friend who's happy not to throw it all away.

I'm pretty new to it but it's hard to imagine it won't be the new standard of care for many situations.


Hey David I just found a dental supply house who will sell at least the bonder to us with no dental license. Otherwise we do what you suggest and ask our dentists to donate old stuff to our cause and they often do.

Author:  Hesh [ Sun Oct 29, 2017 11:17 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

SteveSmith wrote:
I just picked up a unit with a small amount of the binding agent and some small packages of the composite filler (both expired of course). Have not needed to try it out yet but looking forward to it.


Steve you can do your friends and family too..... :D Say ahhhhhhh. laughing6-hehe

Author:  Hesh [ Sun Oct 29, 2017 11:21 pm ]
Post subject:  Re: Light Cured Resin for building up nut slots

dpetrzelka wrote:
I just asked my kid's dentist - they have to retire the UV units occasionally as well. Two months later they called with an old unit ready for pick up.

I do need to work on finding a few different colors of filling medium to match various color bone.


Dave's big on matching I just use a3 or a4 for everything and don't care much to match. The entire patch is under the string and not visible unless..... there is say a broken corner on the nut and we rebuild it with composite material then I do my best to match.

We've been thinking of offering this as an upgrade. Santana's guitars have brass inserts in the nut slots because that's what Carlos likes.

The big point is that this material seems harder than bone to us and so far is demonstrating itself to be longer lasting as well.

Author:  wbergman [ Mon Oct 30, 2017 5:48 am ]
Post subject:  Re: Light Cured Resin for building up nut slots

Do you need UV protection glasses? I have a recollection of the dentist using them.

Author:  Hesh [ Mon Oct 30, 2017 6:35 am ]
Post subject:  Re: Light Cured Resin for building up nut slots

The light guns have a colored piece of plexiglass, ours is orange and you stay behind that.

It's not really UV cured it's simply Light cured for the dental fillings that we use. There is UV in that spectrum hence the shield but not to the degree that one would think if we called it "UV cured" dental fillings. Our's are "light cured" dental fillings. It's just very concentrated light.

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