Glued up rim for semi hollow body

[thistle3585]

Anyone know how Rigel glued up their rims before machining them? Square? Octagon? I'm building a semi-hollow body OM and wanted to eliminate most of the end grain normally associated with a solid body that has pockets routed out of it.

The idea is to glue up a frame using mitered corner joints and glue in a "stile" down the center that would hold bridge and pickup, as well as give some added support to the top, back and neck pocket. The body is somewhat Tele shaped.

[labraid]

I'm not an expert on solid bodies, but couldn't one build the solid body shape then just attach a bent rim around the perimeter? If I'm understanding this one right...

[billhay4]

I think Rigel used a solid blank that was then carved to rim shape. I think that's what thistle3585 is after. This enabled them to have radiused rims. It also enabled them to inset the top into a rabbet to avoid having an edge seam and necessitating binding.
I don't know how the blank was glued up and often have wondered about this -- i.e., how they avoided end grain.
Bill

[labraid]

Anyone have a photo? I'm just plain curious now...

[JEStanek]

Here ya go.. right from their shop
Shop tour page. (http://www.rigelinstruments.com/publish/tour.shtml)

Jamie

[Ted Eschliman]

http://jazzmando.com/images/RF_Stages.jpg

After the top and back are glued, the darker opaque tint of the finish's burst cleverly masks where they are glued to the (solid block hewn) sides. This creates the illusion of the instrument being one solid piece of wood.

[thistle3585]

Can anyone tell, or know, which way the grain is running in the headblock of the CT-110 that is pictured? I thought about bending a rim, as was mentioned earlier, but the bend around the horns would be tough to accomplish even with some thin material.

Thanks for the photos. That kind of answers my question on how thick to make the rim too.

[delsbrother]

What happened to all the wood that was removed for the body cavity? IOW was it just hogged out, or was it cut out and used for something else? I suppose if it wasn't figured it was no great loss; just seems like a waste.

[billhay4]

I doubt if there was much wood where the body cavity is now. If you look closely, it appears these rims were made of several machined parts glued together and then shaped on a shaper or CNC. This would cut the waste and eliminate much of the grain problem (but not all).
Bill

[Ted Eschliman]

No. These were once solid blocks of wood. (Not blocks glued together.) No CNC either, if you look at the Frankenstein contraption in the picture tour, it's a cleverly primitive process.

Darrel, the guts weren't wasted either; the leftover scraps were used to make Women's Underwear (http://www.treehugger.com/files/2006/12/g98_sexy_linger.php#perma) and Vermont Christmas Santas in local Junior High School Shop Classes.

Okay, that last part wasn't true, but the first was.

[thistle3585]

Ted,
They had to be glued up blocks. There are glue joints on either side of the end pin hole that also appear on either side of the neck joint. It appears that the center block was glued perpendicular to the outer blocks. I just wondered if it was a frame or an actual block. A frame would have allowed for less scrap.

[delsbrother]

Was this process patented? Or IOW is there anything stopping another maker from using the same kind of manufacturing techniques? I suppose you could argue the world wasn't "ready" for such non-traditional construction... ? Do you think anyone else would take the Rigel "resonator well" idea any further?

Or for that matter were the Goldtone clones made the same way as Rigels?

[Bill Snyder]

I was under the impression that Rigel did not go under because of lagging sales but for other reasons.
As far as the design being patented you can do a patent search. Take a look here (http://www.google.com/patents?vid=USPATD383481&id=d-InAAAAEBAJ&dq=langdell+mandolin) and here. (http://www.google.com/patents?vid=USPATD383481&id=d-InAAAAEBAJ&pg=PP4&dq=langdell+mandolin#PPP1,M1) This was with a quick search on Google's patent search using langdell and mandolin as the search topics.

[delsbrother]

Wow, thanks Bill, that was neat! I love patent drawings.