Soundhole patch, bridge patch and grafts material. ???

[Tonxi]

I neglected to buy any material for soundhole patch, bridge patch and grafts. There were no grafts on the fist ukes I looked at.
I saw somewhere that the grafts for over the back join should be cross cut from the same material as the back. I have no crosscut mahogany.
Could I just use cross cut WRC?
What about the patches? Offfcuts from the tops or are they supposed to be crosscut too?

[charangohabsburg]

For the grafts I would feel more comfortable with any kind of pine than with WRC. But it may work too. And certainly no grafts at all work too if the back is not "too thin". There are lots of ukes with 2+ mm 2-piece backs without grafts and they hold up just fine.

You only need a soundhole patch with a thin top combined with a rosette. As it is round it always will have two cross-cut sections. I think I have not understood your question well enough.

The bridge patch is only necessary if you make a pin bridge, and it's grain goes normally in 90° to that of the top. It may be made any hard wood.

[Allen]

You'll see plenty of ukes without bridge patches, but no matter what style I'd never build one without a bridge patch sized larger than the bridge itself. Lots of reasons to have one for stability, driving the top, longevity etc. The bridge patch can be any off cut from the top or back itself. Cross grain to the top.

You can also use just about anything for that cross grain bridge patch that you would build an instrument with. It doesn't have to be a hard wood unless you are going to use a pinned bridge. It's function is to distribute the forces of the bridge through more of the top than if it was not there.

Sound hole patch can come in the form of a double thickness of the top. Small braces work as well. You really only need them if the top is a wood that will easily split such as spruce or WRC and is really thin. Many will over build there tops and at 2 mm thick for mahogany, you just don't need a soundboard patch.

For back seam reinforcement the standard in guitars has been a cross grain patch of spruce. On ukes it might be the same but more often than not I see long grain patches of spruce or the same wood as the back or the bracing. Ie if the instrument is using mahogany bracing the brace seam reinforcement is the same.

We are talking about an instrument with a lot less real-estate to control than a full size guitar and far less string tension. Good building practices are always best, but you can vary your techniques as compared to big steel string guitars.

[ozwood]

Hi Guy,

Interesting Thread, Does the bridge plate/patch strictly need to be cross grain ,
Reason I ask is because I once met a Guy who's bridge plates run the same grain direction as the top , he didn't use the X brace system , and the Bridge plate was a bit larger than the usual, and extended forward of the bridge much further than usual , the plate was also shaped and tapered at the edges , he said the reason was that he felt that this method allowed more flex up and down around the bridge area , but prevented less forward tilt of the bridge and less bellying , I'm not sure of his theory , but his guitars did sound great , loud and sweet , and even though some were five years old , no belly or cracks , I appreciate that many factors go into the overall sound , but as he explained his theory it did have some merritt in my mind .

What are your thoughts.

Paul.

[jeffhigh]

Frank Ford at http://www.frets.com is a big advocate of bridge plate grain running parallel to top grain but he seems to be in a very small minority there.
I can see pluses and minuses in both approaches and some split the difference and go with 45 degrees.
I am talking X braced, pin pridges here though.
In a conventionally braced uke, you would definitely want the bridge patch grain running across the body.

[Kim]

Hi Guy,

he said the reason was that he felt that this method allowed more flex up and down around the bridge area , but prevented less forward tilt of the bridge and less bellying

Paul.

There are a few builders in the USA I've seen mention they run the grain with the top for the reason you point out Paul. I seem to recall that it may even have been Frank Ford who put the argument forward that doing so would add strength against rotation but I can't be sure it was Frank. Anyhow there were a few on the positive and among them were some very experienced builders and of that I am certain.

Cheers

Kim

[Kim]

Frank Ford at http://www.frets.com is a big advocate of bridge plate grain running parallel to top grain but he seems to be in a very small minority there.

Well there ya go..thanks Jeff

I will add that while looking for the topic I had referred to above so I could identify in that post who the main proponent was of running the grain with the top, I had noticed that just like many, Howard Klepper chooses skew sawn wood for the bridge patch. But Howard also skews the grain orientation of the patch itself and then skews the alignment of the pins to be in the opposite direction to reduce the chance of splitting along the grain line. Howard also laminates the patch material but goes on to mention that he feels this is not entirely necessary.

Clever boy that Howard, a wealth of professional experience with a wonderful knack for communicating the detail in few words, but in such a way that its very difficult to find anything in what he has shared about guitar building over the years that is not bang on the money. That's a skill which in my view makes him an international treasure to guitar building forums and ranks him right up there with Frank Ford as an educator.

Cheers

Kim

[Tonxi]

For the grafts I would feel more comfortable with any kind of pine than with WRC. But it may work too. And certainly no grafts at all work too if the back is not "too thin". There are lots of ukes with 2+ mm 2-piece backs without grafts and they hold up just fine.

You only need a soundhole patch with a thin top combined with a rosette.

I remember now that I bought a piece of spruce for grafts.
I am putting shell rosettes in both tops as soon as I can decide which shell suits which top best. I made a circle cutting jig for my laminate trimmer an did my test circles. My mahogany top is 2mm at the moment and the WRC is 2.5mm. Both the mahogany and sapele backs are 2mm. My sides are slightly under 1.5mm. Will it sound better if I take a bit more off the backs and strengthen them with grafts? I will loose a bit when I finish the rosettes and will probably take a bit more again out of the tops.
I was going to use WRC for back braces on the sapele. Would spruce be better?

[Allen]

Really depends on what you are planning with the backs. Responsive vs. reflective. For the tops I'd be looking at taking the mahogany a bit thinner, say 1.8 and the WRC down a bit as well to 2.0 to 2.2mm Really depends on the piece you have on hand and only experience is going to help there. With those measurements you aren't pushing the envelope so will end up with a responsive instrument that isn't going to self destruct. Which is a real bummer on your first. From there you'll have learnt a lot and can venture further.

[Tonxi]

Really depends on what you are planning with the backs. Responsive vs. reflective. For the tops I'd be looking at taking the mahogany a bit thinner, say 1.8 and the WRC down a bit as well to 2.0 to 2.2mm Really depends on the piece you have on hand and only experience is going to help there. With those measurements you aren't pushing the envelope so will end up with a responsive instrument that isn't going to self destruct. Which is a real bummer on your first. From there you'll have learnt a lot and can venture further.

I got a message from Greg Smallman via his wife Robbie. He said "make it thin and use only wrc for the tops".
I have mahogany top, back and sides so I may stick with tradition for this 1 especially since I have an all mahogany concert to compare it to. I don't have a mahogany neck blank but that doesn't bother me too much. I have a few more options for necks.
Can I put the rosettes in and smooth the outside, then put them through the thickness sander again, inside up?

[Allen]

Not really sure what you are trying to do with the rosette from your question. I only level a rosette with a freshly sharpened cabinet scraper, especially with a soft top like WRC.

[kiwigeo]

Can I put the rosettes in and smooth the outside, then put them through the thickness sander again, inside up?

I wouldn't put a rosette through a sander....any dark coloured dust will darken up lighter parts of the rosette. The only tools I let near a rosette are a block plane and a cabinet scraper.

[Tonxi]

Can I put the rosettes in and smooth the outside, then put them through the thickness sander again, inside up?

I wouldn't put a rosette through a sander....any dark coloured dust will darken up lighter parts of the rosette. The only tools I let near a rosette are a block plane and a cabinet scraper.

I meant to finish the rosette and put it through the sander the other way up, with the rosettee on the rubber belt.
I have 2 more complete sets to thickness now so I can delay the rosettes and do them all at once if it is a problem.

[ProfChris]

For your soprano build as lightly as you dare. It will probably still be too heavy.

For reference, I have a 1920s Kumalae koa soprano from Hawaii. Weighs in at around 225g! Huge sound, and it's lasted 80+ years.

My sopranos, none of which have yet fallen apart, have a single back brace at the waist, no back strip (even though backs are bookmatched). The tops have a brace fore and aft of the soundhole + a bridge patch. Braces are around 6mm high, 4mm wide. The lightest I've managed weighs 300g.

Top thickness in mahogany - 1.8mm or less. I'd want it nice and springy, half way between stiff and floppy. How thick that is depends on the wood itself.

Tenors seem to run to 2 cross braces, brige patch and 3 fan braces for the top, again as light as you dare. I've not built one, so no experiece. Some use a back strip, some don't.

Caveat: I'm a mere hobby builder, but this fits in with what top-class uke builders say they do.

[Tonxi]

I'd want it nice and springy, half way between stiff and floppy. How thick that is depends on the wood itself.

I've been trying to sell my wife on this idea for a while now. Especially when I'm feeling 'refreshed'.

[kiwigeo]

Can I put the rosettes in and smooth the outside, then put them through the thickness sander again, inside up?

I wouldn't put a rosette through a sander....any dark coloured dust will darken up lighter parts of the rosette. The only tools I let near a rosette are a block plane and a cabinet scraper.

I meant to finish the rosette and put it through the sander the other way up, with the rosettee on the rubber belt.
I have 2 more complete sets to thickness now so I can delay the rosettes and do them all at once if it is a problem.

I generally rough thickness my tops on the drum sander before installing the rosette. Once the rosette is installed any further thicknessing is done with a cabinet scraper and I generally dont touch the area under the rosette.