The Improved Rosette Cutter

[Allen]

I've been using an improvised rosette cutter....well it's actually just a blade from my LMI gramil that I inserted into a block of wood with various pivot points drilled into the body with some rough adjustment with a lock nob that was nothing more than a 8mm cap head bolt. It did a nice job of scribing the line that I would then use my dremel with a StewMac base to then clean out the channel. Lot's of pissing about, and the visibility on the StewMac unit is not that great. Especially when you modify it to work on ukelele size sound holes.

So when Micheal and I had a bit of time at the end of each day over a beer or two, during my Easter break in NSW, we started to improve on my very agricultural design, and well to be honest we wanted to make the best damn one available. Keeping in mind that when others saw it a possibility of selling some would be an option. Pricing is still under review.

The design brief went as follows.

• 1. Be compatible with StewMac type router base
  2. Able to accomodate instruments from ukulele through to guitar
  3. Cut and route out the inlay channel
  4. Work as a gramil (that is what that brass fence is for)
  5. Have a course adjustment for quick positioning, and then a precision fine adjustment
  6. Made from quality components (Brass and Stainless Steel)
  7. Easy to use on even the kitchen table if required.

After working out what we wanted to accomplish with it there was some prototyping that nutted out a few issues. Back to the drawing pad and then right back to the mill and lathe. From those 10 days and some more work by Micheal since then, we've now got to a very serviceable prototype.

There are still some modifications that will be done to improve its ease of use such as a left hand thread for the fine adjustment, but I'll post our working model here for all to see, since it was mentioned by Bill in another thread.

Installed in the cutter is a blade for cutting one side of the inlay channel. We have two and they both can be installed to cut the inside and outside edge at the same time. Also in the picture is the 3mm wide chipper. We have a 2mm and 1mm one as well.

Liam was over yesterday and he got to have a quick play with it. Took a piece of NGR and cut a quick rosette channel in it. It would have been less than 5 minutes on his first go....and we were drinking a beer at the time.

And during the day I was installing a rosette for a new commission. This would certainly rank up there with one of the more difficult rosettes to inlay, especially when you consider its in Western Red Cedar.

Not all of this rosette was done with the new tool. We designed it around the ability to swap it out for the StewMac or similar base as it uses the same 3/16" pivot dowel. So the fine channel for the red line and the inner black line were done with the dremel. Everything else was done with the new tool, including cutting the inlay material and routing out the stopped channels for it. I've scribed the sound hole but will wait until I have the reinforcement on the back side before cutting out the sound hole.

[Kim Strode]

When are they going on the market....want one!

[liam_fnq]

I hope you've got enough for the mother's day rush.....

[Localele]

As soon as the left hand tap and dies arrive I will get to work Liam. Hope to have a few ready to take along to the Brisbane Woodwork Show later in the month.

[Nick]

Ooooooooooooooo Shiny new tools! Very nice Allen, I'd say you shouldn't have a problem selling these Micheal.

[Patrick Hanna]

Allen, from way over and up here it certainly looks like you've got it working. That's a very interesting rosette, and nicely done, too. Now let me be sure I understand how the tool works. Here's my go at it: Left thumbwheel locks the cutter in place. Insert pin and spaced holes on the bottom are the coarse adjustment. Right thumbwheel is the fine adjustment and top thumbwheel locks the sliding bar in place....is that all correct? I'm sorry to say I don't understand the flat fence. When you have time, maybe you can demonstrate that, too. Nice looking tool!
Patrick

[Localele]

Hi Patrick, The fence was originally designed to have 2 jobs. When it is mounted vertically it is for use as a Gramil. To scribe around the instrument before cutting binding and purfling channels.A nice light score to save on tear-out with the router both on the top and side of the instrument..We toyed with the thought of the horizontal mode for box work.Current talk is to use a round fence for Gramil work with possibly both a 1/2 and 3/4" version.The smaller one for tight curves like mandolins.
Any constructive design help is appreciated here.

[graham mcdonald]

Can I have one please

g

[Patrick Hanna]

Okay, Allen, I think I'm getting it now. There are some mounting holes and a curved surface that didn't show in your first picture. This makes more sense to me now. Yes, I have a gramil so I understand the way the tool would be used. I just couldn't figure it out from your first picture. As I said earlier, it sure looks like a nice tool to me! Well done. I hope you have great success with it! I'll probably be looking for one, too.

Patrick

[Allen]

You pretty much have it figured out Patrick.

The holes on the bottom are threaded to accept the pin's or bolts for the fence.

You will notice that in Micheals photos that the chippers are scrappers, and do not have a hook on them. They work brilliant on hard wood like that, but we had trouble with soft wood, so have added the hook that you can see in my photo.

[Dominic]

Looks pretty cool to me. To get how it works, the brass knob on the end allows you to advance and retract the blade and the one on the top locks it in place. But, is the steel rod connected to the brass knob on the end or is it free floating? If they are connected securely you could lose the lock knob on top and use a nice sized locking nut on the end, one you could easily tighten up and loosen by hand. Make it slicker.

I'm in for one. What's a decent critical mass for you to go into production? You could leave them rough and let us do the cleaning up and polishing. And throw in some cutter blanks and hints on shaping and sharpening them would also be cool. I'm thinking you can do testing on us to perfect it and then sell it into the US market if it turns out to be worth it financially. That would be cool.

Cheers
Dom

[Dominic]

Just another thought, could you find a spot to drill a hole crosswise that would fit the steel rod and be able to lock it in like the LMI gremal so you do away with the add on fence. That would be an elegant solution. Do you need all the pin holes? I am sure you could lose one right at the far end or even stretch it slightly so you can still reach all sizes by adjusting the rod.

cheers
Dom

[mqbernardo]

very nice! i´d take one too (if it will become available).

[Allen]

The stainless rod is connected to the adjustment knob on the end via what will be 1mm pitch left hand threads. That's the fine adjustment back and forth. 1 full turn gives 1mm movement.

You do need a locking knob as a round rod in a round hole will rotate on you, especially as you are cutting. That is one of the shortcomings of the LMI gramil that I have. The blade is much narrower than the slot they have and you really have to tighten down the locking grub screw on the blade or it wants to roll back and forth. The blades on this unit are sized to fit the slot in the end quite precisely. It takes just the smallest of turns on the locking knob to have everything nice and snug.

The holes on the bottom are to give a wide range of adjustment. Not just instrument rosettes, but also the possibility that box makers will use this for string art. Have a look at Lee Neilson's inlay range and you'll get an idea. More work to be done on that aspect yet, so for the time being no claims are being made as to it's suitability.

[Localele]

You could leave them rough and let us do the cleaning up and polishing.Cheers ,Dom

There are a few more things to try and a few changes to dimensions but one thing I can guarantee Dom "I won't be leaving them rough". The photos are just as finished off the lathe but I won't buff them up to a high polish.
I will try to get some new parts done today for a demo and to use the momentum of ideas that come from this forum .It has a great depth of thinkers and tinkerers.

[Dominic]

With the fence, does it overhang the end of the outer sleeve? Its hard to tell in the pic but it looks like there is a little lip there.
Cheers
Dom

[Localele]

Yes Dom it does overhang but I am thinking of making that fence fro "Gramil" work into a round bar.It will of course still overhang. I will look at having both a 20mm and 12mm diameter fence so it will work into tighter bends.

[Lillian]

Love the rosette Allen.

Can I be put on the list as a maybe?

[Bachiano]

Sweet tool Allen.
Will you sell direct?

[Allen]

The idea as it stands right now is that Micheal will build a batch and we'll sell them direct.

Have considered the idea of other distributors, but then you have to factor in a margin for them and it just starts to make what ever you want to sell far more expensive for the end consumer.

[H3ytm@n]

Count me in!

[EricDownunder]

I like what your doing creating a nice hand tool, count me in for one, but beware of distributers I established a couple of distributers to retail one of my products about 25 years ago then they had a margin of about 35%, today I supply the same product for arond $60.00 and they retail for allmost $400.00 totally destroying it's sales in my opinion but once you make your bed you gotta lay in it I suppose.
I highly recommend you sell direct, your cuctomer will apreciate it and will come back, the $ stay's in your pocket, that is my experence with other products, you don't sell as many but it's more fun and less stressfull.

[Bruce McC]

Please add my name to your list of interested buyers.

[Dominic]

Yes Dom it does overhang but I am thinking of making that fence fro "Gramil" work into a round bar.It will of course still overhang. I will look at having both a 20mm and 12mm diameter fence so it will work into tighter bends.

Thanks, what i was wondering about was how it would handle something a violin plate before being glued to the body. If it slipped off the handle it could stuff up your line. If you follow me. And the knife would have to extend a bit making it less stable. Perhaps. I am just going by a couple of pics which don't show me that bit. I apologise for poking at it, I think it looks very cool and am just thinking out loud.
Cheers
Dom

[Dominic]

Perhaps the gremlin bar could step up and meet the adjustable knife rod. Might make it more stable and a round gremlin rod could be attached with on screw bolt. Even neater, a round rod with 10 or 15mm cut out lengthwise and a hole drilled trhough that section to slip over the knife rod and then one screw holding the body of the gremlin to the body of the tool. I can see it clearly in my head but I am not sure if I got it in words. Let me know and I'll try to draw a picture.
Cheers
Dom