Query re Grellier soprano plan

Hi I built a soprano uke using the Grellier plan I downloaded. It does not show any fan braces under the bridge so I built it this way. However after being strung up for a week or so it developed a substantial dip in front of the bridge and looking at the bridge from the side it had noticeably rotated towards the nut. I have routed off the top and am making a new one with three fan braces as per the concert uke plan I have. Has anyone else built sopranos without fan braces or is there an issue or mistake in the Grellier plan or did I just make an arse of it? Will post pics once new top is on!

Cheers, Bob

To quote our esteemed Ken Timms (Timbuck): "On my Sopranos there are no fan braces just the long bridge patch and two transverse braces at the sound hole".

If Ken does it that way, then that's the way its done.

I've only made a few sopranos, but I would think that if you made a soprano with 3 fan braces, the soundboard would be far too stiff and hence all treble.

Did you make the top 1.5mm thick and did you fit the 2mm bridge patch as shown on the plan?

Here is a set of pics of an ancient Koa soprano that I restored..there was no dip in this sound board and there is hardly any bracing and no bridge patch...and the top was about a sixteenth of an inch thick.

Further to this thread..If you have a thick fretboard and a high saddle ..this will increase the pull on the bridge..most of these old sopranos only have a saddle hight of about 1/4 inch...this old Mossman uke bridge was only about 7/32" high...and no fretboard

The Grellier plan is the most accurate out there. If you build correctly and that means using the right materials it should be fine.

greenscoe said:

To quote our esteemed Ken Timms (Timbuck): "On my Sopranos there are no fan braces just the long bridge patch and two transverse braces at the sound hole".

If Ken does it that way, then that's the way its done.


Did you make the top 1.5mm thick and did you fit the 2mm bridge patch as shown on the plan?

Click to expand...

Yes top thinned to 1.5mm and 2mm bridge patch as per plan. As Timbuck said perhaps fingerboard was a bit thicker than it should be. Have glued braces on last night but plan to scallop them and taper the ends away to nothing. Will post pics when finished and see if my son can help me sort out a sound clip. Thank for the input, what a great resource this forum is. BOb