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I started a couple of Celtic style mandolins. These will have walnut back and sides, flat/braced backs, Sitka tops, Honduras mahogany necks and African blackwood fretboard and headstock veneer. My buddy Tim is in training during these and doing well. This starts a series of photos and video during the construction.

Enjoy!

You may have seen this in a previous post.... the pillowy Illinois Black Walnut.

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Here is Tim resawing the walnut for our backs.



That is a Delta 14" with 4" riser and Kreg fence. The blade is a 3/4" x Wood Slicer.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

In case you didn't watch the video, here is Tim resawing walnut lumber for our backs.



Here they are glued up. We use hot hide glue.



Once dry, the backs are thickness sanded using the drum sander.



Here they are ready to be trimmed and braced.



Happy Thanksgiving!

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Looking forward to seeing more on this . When is my walnut shipment comming in btw

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The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Thanks Chris and Jim. I really like the walnuts too... claro is beautiful stuff.

Jim, you haven't sent me your measurements yet...

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Looks great! I will be happily following this thread. BTW Jim is probably too shy, but since I have met him I can estimate his measurements for you. . .36-24-36.

Jim, that ought to get you a nice stock, feel free to share. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

You have it backwards I have large belly its 24...36..24

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The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

I'm not sure I have either size available.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

I prefer ABW to the European. I have a few sets that were planted in Kew Gardens (London) in the 19th century, probably brought over as an ornamental tree. Reminds me of good Chocolate. Lovely.

Our last sunset tonight before returning to the shop. There is no black walnut over here.... but plenty of koa.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

... so how are mandolins "celtic" instruments? because they were popular in the 1960s folk movement, which afflicted all white people all over the earth?
by that rite, are fender stratocasters and gibson les pauls "traditional african instruments" as well? because they are prominent all over 1960s-70s afropop music.
as someone who is half irish, i cringe at the whole emasculated "celtic" lite-folk rubbish...my ancestors were never a culture of manicured, limp wristed Yannis! mandolins and dreadnaught guitars are "celtic" like '50s Chryslers are Pakistani

Ahhh... post party wisdom.
It appears that you have asked and answered your own questions.
congrats on your heritage.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Finally, home and back in the shop. I've got the backs ready and bracing cut. One will get an X-brace, the other parallel bracing.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Hope this isn't too many photos.

Here are the two backs with cross-grain seam reinforcement being glued.


I marked, cut and chiseled out the slots for the bracing.


Next, sanded the 15' profile on the braces and glued them in place.


Now it is ready to have the braces shaped with a sharp chisel, a little sand paper and some attention and patience.


Here is the other back getting the x bracing fitted.


The x braces interlock. I prefer to glue down the first before moving on to the second as the glue needs to be worked with as quickly as possible.


I use hot hide glue for all the bracing. Before applying the glue, the parts get their temperature raised using a heat gun. The whole operation from start to finish took just over 4 hours including wait time and dinner.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Chris, nice work I've been following you and your mate. I understand differnt bracing on tops why on the backs?

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Regards from RangeView, Bill

Thanks Bill,
Let's just say, the customer is always right, right?
I am following Graham's suggested x-bracing, on one and my own experience with back bracing on the other. All I can tell you now is that the x-bracing adds a little more labor in the notching and shaping process. I guess we'll see if one or the other holds its shape any better or worse down the road.

I don't know if you use any back bracing in those double basses you make. If so, have you had the opportunity to try different styles?
chris

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Chris my bass has a carved back, no braces. Flat back basses have 3 braces shaped at the ends to give the back a slight curve. The flat backs sound just as good with less work and matreial invested.

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Regards from RangeView, Bill

The back braces have been shaped and sanded.





One question Bill asked, above, was why the different bracing patterns on the backs. I am following Graham's plan on one back (the X braced) and my own experience on the other.

Here is some comparison data between the two.

x-braced
Black Walnut with Sitka Spruce bracing.
thickness: .09 - .11 "
weight: 4.14 oz
tap tone in the top, left, right, bottom and finally center:
http://www.infinityluthiers.com/audio/x-braced-back-12-01-06.mp3

parallel braced
Black Walnut with Sitka Spruce bracing.
thickness: .10 - .11"
weight: 4.61 oz (note: this back has considerably more walnut to trim than the x-braced back and should bring the weight down to less than 4 oz.)
tap tone in the top, left, right, bottom and finally center:
http://www.infinityluthiers.com/audio/p-braced-back-12-01-06.mp3

Here you can see the open grain left unbraced on the x-braced back. It is very flexible in this section.


On the parallel braced back, this area is fully braced. As a result, the entire back is stiffer. If you listened to the tap of this back, you may have noticed that produces a tighter tone.


Once the backs are glued to the rim the backs should both stiffen up even more. It will be interesting to go back and flex these areas at that time to see if there is a difference.



My overall preference so far is the parallel braced back. It was less work by far, has a tighter tap and is more rigid over the whole back. Another comparison to consider is future repair. If a brace were ever to be knocked loose, the parallel bracing should be easier to repair. On the other hand, the x-braced back might be more shock resistant?

Next step, fabricating linings.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

I think like the parallel bracing more, assuming the same tap pressure, it has a bigger tone. It'll be interesting to compare the finished mandos.

_________________
Regards from RangeView, Bill

I know... this is way too much info, but...

Linings

I start with a billet of basswood. Get a nice 90 degree angle on the jointer.


Now slice off a few strips.




Set up the kerfing jig.... which is really just a straight piece of maple used as a stop. Set the depth of the kerf cut, clamp it down and get started. I put a line on the jig to help me align by eye. I back the basswood piece with the miter gauge. This also keeps it perpendicular to the table.





Once complete, remove the jig and rip out your individual strips.


Now set your table at an angle and finish them off.


There you have it.


Just sand of some of the basswood fibers and they're ready to use.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Attaching the lining.

I use clothespins that have been altered a bit. This allows them to clamp down on the lining without slipping. Also, I do wrap rubber bands around the jaws of the clothespin to create more clamping pressure.











Next up we'll be sanding the linings flush to the backside of the rim.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Sanding the linings

We'll be cutting the dovetail before the back is glued in place. Because of this, we are able to sand the linings flush with the backside of the rim and have a flat surface to allow easy cutting of our dovetail mortise.

I use a pencil and a flat sanding stick for this operation. The sanding stick is just a piece of plywood long enough to lay across the rim. I have 60 grit sandpaper adhered to the stick on one end.

Here are the two mandos ready for their linings to be sanded.



Here is the sanding stick. Notice the pencil lines on the lining to show me where I have sanded.


Here I have sanded the pencil marks off the lining and have reapplied a line to the bindings and, more importantly, to the rim itself.


I have arrows here showing where to make your pencil marks on the rim. When sanding the linings, you want them to be flush with the rim without eating too much into the rim.


All done. The top of the rims will get the same treatment before gluing on the carved tops. The back will be sanded to radius before it is glued on to the rim.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

I've never seen bulk kerfing before. Great!

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Regards from RangeView, Bill

No basswood down there? How do you make those beautiful basses?

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Jointing, Sawing and Gluing Up the Tops

I had wanted to top one of these with cedar but I didn't have any thick enough (that I could find). I do, however, have a lot of old Sitka billets. Here is part of the same billet I used on my last A model. It has great strength and super tight grain... more rings per inch on the glue edge than I can count.


Here is one inch of the end grain.


Here I am jointing the glue edge. By flattening this edge, the glue edge, I'll be able to glue up immediately after resawing.




These tops will be great.


A little heat gun on the glue edge, some hot hide glue and a few clamps and we're off. Because the boards have extra thickness (to be removed later) I didn't have to worry too much about aligning the edges perfectly.


If you do any other woodworking, you owe it to yourself to get a couple of the Jet clamps and give them a try. They are the best I've used.


Next up is thicknessing and cutting out the tops.

_________________
Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...