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I just cut my first rosette using my DIY jig and Dremel. To everyone that says this is not a good method, I think you're doing something wrong. My test cut was done with a regular upcut bit and it was terrible so I got the SM downcut bit and the cut is as clean as a whistle. I guess if I were making real wide rosettes I may want a larger bit and router but for this Martin style herringbone rosette, it was a piece of cake.





Now I have to get some shellac and CA.

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Hutch

Get the heck off the couch and go build a guitar!!!!

"My test cut was done with a regular upcut bit and it was terrible so I got the SM downcut bit and the cut is as clean as a whistle."

A new sharp bit often makes all the difference.

Well, I won't say that the Dremel can't get the job done, as I did probably the first 100+ of mine with one, maybe more, and I still use it from time to time with a 1/16" bit in it. But, I will say that once I switched over to a laminate trimmer, I silently wept for all the time lost by using a Dremel:)

But seriously, it will do ya for a long while, but I would suggest adding a trimmer setup to your 'future improvements' list...

Looks like a serious router base for the Dremel. I've tried dremels with various router bases and found it allowed the bit to wander....I'd usually get that hairline gap somewhere when the bit grabbed the wood grain too much. No huge problems but that 0.0005" gap that only the builder can see.
I'm a laminate trimmer guy now. Its just more solid.

I have and use both . It depends on the cut I an trying to make and the material in question . The Laminate trimmer is By far a better choice , however used properly the dremmel tool can do / does a good job .

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The only incentive I would have for going back to a Dremel would be to take advantage of the decent base and jigs that StewMac carries. But I like the power and weight from a laminate trimmer better, and with a really good base and jigs (Bishop Cochran), a laminate trimmer really is way better. A Dremel with sharp bits is fine. A laminate trimmer just works better.

I will definitely be adding a trimmer in the future, for now, this works pretty durn good!. It's done and I won't be doing another for quite a while.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

I'm going to pick up some shellac today to protect the spruce from soaking up CA. I've got a pretty snug fit on these rings and recent threads here are calling for 3 coats of shellac. I'm wondering if I'll still be able to get the rings in place with all that shellac.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Hey Sarg! I used a D*emel too for over 50 rosettes with good results.

The criticism of D*emels is that there is lots of runout making for a bit of a sloppy fit and cut. I found that to be very true too.

As such I modified mine and started with a brand new one that would never be used to cut the muffler off my car, etc. and instead reserved for rosettes. Next I shimmed the bearings with paper to tighten up the thing and reduce runout.

Lastly I was never a fan of CA for anything Lutherie beyond gluing frets, a drop for my nuts..... on the guitar... and in the repair world drop filling dings in Polyester finish.

Instead I used Titebond original for rosettes and decided that since I can't fight this glues tendency to swell fibers I would use it to my advantage. I cut my rosette channels for a non-snug, press in fit and then moved my arse quickly when applying glue and pressing in the rosette with my fingers. The glue swelled everything up nice and snug and it stayed that way including on the samples/guitars that I have here and kept nearly 15 years later.

Wax paper over the glued rosette and some weights applied over the entire thing and Bob's your uncle. Wonder how Uncle Bob is but I digress.

Anyway no need for shellac when nixing the CA. I know this will not sit well with the CA crowd but I avoided all the issues associated with CA simply by not using it AND I tightened up the effective fit of a D*emel cut channel by exploiting the tendency of wood to swell with Titebond Original.

Worked great, less filling or in this case more filling...

I can't change my mind now, I just ordered the CA and whips.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Well, if the CA stains the wood around the rosette, you might wish you had changed course. I’m with Hesh, although my chosen adhesive is hot hide glue, not Titebond. Yes, water-laden glue will swell the parts. But it won’t stain the wood. Swelling can be planned for. Staining has to be either prevented or fixed, and fixing might not be possible.

There was a thread recently from someone who swore up and down he had used enough shellac on some torrified wood before using CA on the rosette. Well, he was not correct about that. It still seeped through and stained the wood.

CA and spruce can make you cuss like a sailor. Just sayin’.

I haven’t upgraded to a laminate trimmer, I do plan to at some point. I also use a dedicated dremel and will try Hesh’s recommendation on the bearings.

For bits, John Hall posted a few years back about Burchett tools. They sell end mills for cheap. So cheap you can afford to use a new one with each rosette, but I have found they last quite a bit longer than that.

https://www.bqtool.com

I order part number 2F062 and 2F125. They are a 1/16” and 1/8” diameter end mill. They have been nice for this job. Drill bit city is another place to get bits for this operation for a reasonable price.

Brad



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Whips are great for self flagellation, and CA also stands for "Cover your A**", so you better order a can of Zinnzer's spray shellac to go with that.

I use either method for installing rosettes, depending on the type I am doing. For working with shell materials I find it easier to put them in place and then flood them with thin CA. Premade wood or fiber rosettes can be glued in with HHG or titebond, leaving the channel a little loose to account for the swelling , as others have mentioned.

I never had issues with CA and remember seeing a behind the scenes video from Taylor showing that they use it too. Just go heavy with the shellac to seal the channel. Taylor sprayed Zinsser from the can.

*That said*. I prefer using Titebond now for all the reasons already mentioned. It will aid in swelling gaps shut, and no chance of staining. While I personally haven’t had a problem, I have a friend who lost a very expensive redwood top to CA staining.


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Regarding the adrenal, if it worked for you, cool. Not every tool can be top shelf at first.

One area where I think you’ll find the trimmer luxurious in the future is in the binding process. It’s one thing to cut through a few mm of softwood like spruce, but rabbetting that hardwood will be a different experience. THAT said, many have come before you with a Drexel before and gotten the job done.


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" THAT said, many have come before you with a Drexel before and gotten the job done."

If you can do it with a popsicle stick and an exacto blade then you can probably do it with a dreidel, but I wouldn't gamble on it!
(how far can we take this silliness - whose next?)

James, was it CA or Titebond that ruined the redwood top? What did it do? I recently had some slight discoloration when binding WRC using CA and didn't seal with shellac.

Good catch--I just updated the post! I was posting quickly in the car (I was the passenger )...

It was CA, and my understanding is that there was some significant staining.

The OLF is littered with posts about tops being ruined by CA stains. I've been here getting close to a decade and a half, over 30,000 posts personally with multiple IDs and CA staining tops has to be in the top ten repeated issues reported here.

Personally I'm far more comfortable using materials that are traditional and known, knowns.

At least with nitrocellulose lacquer we know that about 100 years out it will all deteriorate and flake off and your clients will be milling around outside your homes with pitchforks and torches chanting that they want your head and their money back.

I hear the tune "Tradition" from Fiddler On The Roof in my head.

To be fair, there are posts connecting just about every glue to staining. I won't question others' experiences, particularly since a friend and well-known luthier lost a top to it, but if factories producing a guitar for every post I make use CA, maybe they're just careful about sizing the softwoods with shellac before using it.

I went to find that Taylor video but couldn't. I did find this from PRS. Like I said, I use Titebond personally, but using CA seems to be embraced as a perfectly valid method by those higher up than me.

Hey James: Hope that you're doing great my friend.

There is no winning or losing in these discussions and everyone should do whatever they wish, always.

It's also true that some folks do use CA with decent results and many use it for binding too with decent results.

My choice is and was to do neither and to play it safe with good old Titebond and using of course only wood or fiber bindings and purfs. I do recall a thread or two about Titebond showing under finish but I personally heavily discount these very few reports as likely poor surface prep and not something that would or did cause me to seek an alternative. I've never had Titebond stain any wood that I've used it on.

No worries my suggestion from the trenches is and remains there is a simple way to avoid having to worry about staining one's tops and that is to nix the use of CA for that application. That's all I'm suggesting.

Two other choices of glues that are available are epoxy and hot hide glue. Epoxy being more viscous may cause less problems with staining and be a good choice for gluing relatively non porous materials. Hide glue tends to "disappear " under finish and cleans up easily with water.
As Hesh mentioned titebond "stains" are usually because of sloppy technique and the surface not being sanded enough to remove all the glue. In some cases with porous woods and the thin scantlings we use, sanding to remove the glue might remove too much material. Removing the glue with water can sometimes spread a thin film over a wider area. Better technique (not getting glue where it doesn't belong) usually solves titebond staining problems.

If the channel is sealed, there’s no risk of staining. Just make sure you get at least two coats of dewaxed, super-blonde on the top and in the channels before seating the purfling and using thin CA to get everything glued in. CA also has the advantage of holding onto everything, including hard-to-glue materials like ABS, PVC, and plastic alloys like Bolteron.

Worth noting that Zinsser’s Bulls-Eye Clear spray shellac is perfect for the job...it is 1 pound cut and fully dewaxed. The shellac does not appear to age in the can, and can be sprayed into a plastic dose cup for brush use. A scrap of Bounty paper towel does a nice job of cleaning out excess shellac in the purfling channel.

One other note on Titebond...make sure the purfling is well seated in the channel and has a squeeze-out path. One of the most difficult repairs we have seen was a Martin re-top by a very well-known builder where the rosette was glued with Titebond, but never pushed deep enough in the channel to bottom out. What appeared to us to have happened was that after the repairman surfaced, braced, installed, and finished the top, the Titebond continued to shrink and drew the purfling almost 0.010” down into the channels...creating a very weird look as the lacquer detached from the plastic rosette material. Recutting an existing rosette in situ is always a challenge, and especially when a wider purfling element cannot be used.

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Three coats of Zinsser’s Bulls-Eye Clear spray shellac have been applied and I'm still waiting on the CA. I should have this done tomorrow morning and begin fitting braces. With so much opinion on this method, I'm glad I decided to try it for myself. There are more guitars in the making and hopefully I'll get a chance to try many methods and decide for myself.

I'm happy to read here that Taylor uses this method so I'm expecting good results.

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Hutch

Get the heck off the couch and go build a guitar!!!!

always use a downcut in wood.

I thin fishglue &use a non snug fit like Hesh does.
The glue is brushed on the top of the rose also.

Mike

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Mike Collins