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mikeyb2
01-30-2016, 06:36 AM
I know there are 2 current threads concerning intonation and I didn't want to hijack them. The information given in the other threads is so varied and conflicting at times, so is confusing for a newbie. So I just want to ask a simple question, based on what I've read so far.
It seems to be agreed that for a tenor 17" scale, add 3/32", but does this 17 3/32" from nut, run to the front of the saddle slot or the centre of the saddle slot? Thanks Mike.

BlackBearUkes
01-30-2016, 09:19 AM
Add the 3/32" to the bridge end. The scale length is 17", half of that is 8 1/2". Make the distance from the end of the fingerboard at the nut end 8 1/2" to the center of the 12th fret, make the distance from the center of the 12th fret to the edge of the bridge saddle (or were the string leaves the saddle edge) 8 1/2" plus the 3/32" compensation.


I know there are 2 current threads concerning intonation and I didn't want to hijack them. The information given in the other threads is so varied and conflicting at times, so is confusing for a newbie. So I just want to ask a simple question, based on what I've read so far.
It seems to be agreed that for a tenor 17" scale, add 3/32", but does this 17 3/32" from nut, run to the front of the saddle slot or the centre of the saddle slot? Thanks Mike.

mikeyb2
01-30-2016, 09:46 AM
Add the 3/32" to the bridge end. The scale length is 17", half of that is 8 1/2". Make the distance from the end of the fingerboard at the nut end 8 1/2" to the center of the 12th fret, make the distance from the center of the 12th fret to the edge of the bridge saddle (or were the string leaves the saddle edge) 8 1/2" plus the 3/32" compensation.
thanks for the reply, but when you say where the string leaves the saddle, are you referring to a new saddle whereby this would be the leading edge? Sorry to labour the point, but on a 3mm saddle, the difference could be 1.5mm from the front edge to the centre of the saddle. Thanks.

BlackBearUkes
01-30-2016, 11:33 AM
It doesn't matter where the edge is on the saddle, front, middle or back, measure from where the string last touches the saddle. I mostly set the intonation of the bridge saddle by the first or A string, and further compensate from there, the heavier or thicker bass string getting slightly more compensation. I have been doing this stuff for so long I don't even think about it too much. If you are going to compensate every string to a different length, than my suggestion to get the high A string distance right and the rest will fall into place.


thanks for the reply, but when you say where the string leaves the saddle, are you referring to a new saddle whereby this would be the leading edge? Sorry to labour the point, but on a 3mm saddle, the difference could be 1.5mm from the front edge to the centre of the saddle. Thanks.

mikeyb2
01-30-2016, 11:53 AM
I'm sorry, but maybe I should have said I am asking the question so as to place my bridge in the right place on my first build. So it does matter where the edge of the saddle is, when trying to measure the correct distance.

anthonyg
01-30-2016, 12:11 PM
Yes, your carefully positioning the saddle in relation to the scale length. The bridge falls where the bridge falls. Its the saddle your working with. Timbuck posted a picture of the tool he uses to locate the saddle in another thread.

How thick is your saddle?

The goal in locating the saddle is to place it so the A string, and reentrant G string intonate well when the contact point is very close to the leading edge of the saddle and the C and E string intonate well when the contact points are further back near the trailing edge of the saddle.

Anthony

Yankulele
01-30-2016, 12:17 PM
Hi Mikeyb2,

I'm not much more knowledgeable than you about this, so be careful in considering my answer. That said, I am one of the people who asked this question, and have been working through the conflicting replies as well. Here is the conclusion I have come to, and perhaps others will pile on to confuse or clarify further:

The starting distance for nut to the point at which the string is to begin vibrating freely with compensation for a tenor ukulele is about 17 3/32". If you measure that distance to the front of the saddle slot you give yourself more room to further compensate for the individual intonation of each string. I understand that you are unlikely to need less than the 17 3/32", but you might need a smidge more for the c string, possibly any others. In this scenario, your saddle may be filed so that each string can begin to vibrate freely at a different point, i.e. it will not be crowned evenly across its entire length.

That said, if you are doing your first and you are unlikely to go this deep, it might be easier to measure to the center of the saddle slot, crown the saddle evenly, and call it good.

Hope that helps,

Nelson

mikeyb2
01-30-2016, 02:01 PM
Hi Mikeyb2,

I'm not much more knowledgeable than you about this, so be careful in considering my answer. That said, I am one of the people who asked this question, and have been working through the conflicting replies as well. Here is the conclusion I have come to, and perhaps others will pile on to confuse or clarify further:

The starting distance for nut to the point at which the string is to begin vibrating freely with compensation for a tenor ukulele is about 17 3/32". If you measure that distance to the front of the saddle slot you give yourself more room to further compensate for the individual intonation of each string. I understand that you are unlikely to need less than the 17 3/32", but you might need a smidge more for the c string, possibly any others. In this scenario, your saddle may be filed so that each string can begin to vibrate freely at a different point, i.e. it will not be crowned evenly across its entire length.

That said, if you are doing your first and you are unlikely to go this deep, it might be easier to measure to the center of the saddle slot, crown the saddle evenly, and call it good.

Hope that helps,

Nelson
Nelson, your point about starting distance leads me to the answer I was hoping for, in that the 17 3/32 " is to the front of the saddle slot and thereafter compensation can be achieved on individual strings by shaping the saddle. That seems to make sense to me , and I think Pete suggested something similar in the other thread by saying the nominal scale length of 17" is from the nut to the front of the bridge, assuming the saddle slot is 3/32" from the front of the bridge.
And Anthony, although you are using a different way to describe this, I think you are saying the same thing. The saddle thickness is irrelevant unless it's too thin to compensate the other strings that require additional compensation. It can't be too thick.
thanks everyone

anthonyg
01-30-2016, 02:19 PM
Nelson, your point about starting distance leads me to the answer I was hoping for, in that the 17 3/32 " is to the front of the saddle slot and thereafter compensation can be achieved on individual strings by shaping the saddle. That seems to make sense to me , and I think Pete suggested something similar in the other thread by saying the nominal scale length of 17" is from the nut to the front of the bridge, assuming the saddle slot is 3/32" from the front of the bridge.
And Anthony, although you are using a different way to describe this, I think you are saying the same thing. The saddle thickness is irrelevant unless it's too thin to compensate the other strings that require additional compensation. It can't be too thick.
thanks everyone

Start with the 17 3/32 " to the leading edge of the saddle and see what happens. If by chance you have gone too far and the intonation goes flat you can correct this by compensating the nut position a little. If you move the nut away from the 12th fret you sharpen the intonation. If you move the nut towards the 12th fret you flatten the intonation.

Anthony

RPA_Ukuleles
01-30-2016, 03:23 PM
Start with the 17 3/32 " to the leading edge of the saddle and see what happens. If by chance you have gone too far and the intonation goes flat you can correct this by compensating the nut position a little. If you move the nut away from the 12th fret you sharpen the intonation. If you move the nut towards the 12th fret you flatten the intonation.

Good lord :(

anthonyg
01-30-2016, 07:11 PM
Good lord :(

Well, to be honest I think that the recommendation for 3/32" compensation to the LEADING edge of the saddle is too much. 3/32" compensation to the MIDDLE of the saddle is probably more like it but I'm not here to overrule the experienced builders. I'm just stating that if the intonation goes flat, don't tear your hair out as there is another fix.

My Wise ukulele which has quite good intonation has 2mm of compensation to the leading edge of the saddle but also about 0.5mm compensation on the nut. I don't want to tell you guys that this is how it should be done but its a solution that works. Since I've changed strings the intonation has changed a little but it was very close with the original strings.

Anthony

mikeyb2
02-12-2016, 02:05 AM
sorry to resurrect this thread, but I was just reading the Stewmac Tenor kit instructions, and it says( for their kit) to set the distance of 17 3/32" from nut to 'centre' of saddle.

anthonyg
02-12-2016, 03:05 AM
sorry to resurrect this thread, but I was just reading the Stewmac Tenor kit instructions, and it says( for their kit) to set the distance of 17 3/32" from nut to 'centre' of saddle.

3/32" is close enough to 2.4mm. My Wise Tenor ukulele which is built for linear tuning only, has 2mm of compensation to the leading edge of the saddle on the treble side and 3mm of compensation on the bass side. The balancing trick here is that if you don't go far enough with the saddle compensation then the thicker strings still go sharp. If you go too far then the thinner strings go flat. If your only using a 3/32" (2.4mm) thick saddle then its a FINE balancing act. Try a thicker saddle material of say 1/8" (3.2mm) at least. Ideally you don't want the required contact point to be EXACTLY at the edge of the saddle because you want to be able to round the contact point a little.

Either will work really. If its out then adjust the nut slightly. Move the nut towards the frets to flatten the intonation. Move the nut away from the frets to sharpen the intonation. From what I've seen and measured the two outer strings do well to have the nut contact points SLIGHTLY closer to the frets than the two inner strings.

Anthony

SkiAloha
02-12-2016, 03:50 AM
FWIW, on my first build I positioned the saddle so that its CENTER was at 17 3/32 from nut (8.5" + 3/32" from center of 12'th fret). Was able to file to componsate "perfectly" for each string. The saddle was about 1/8" thick. When compensating, I ended up filing the A string closer to the leading edge (closer than the middle - perhaps my measuring was off?) the C was farther back, the other two fell in between. I am happy with the results.

mikeyb2
02-12-2016, 04:38 AM
Thanks, I've decided to go with the centre saddle idea, and I'll be using a 3.2mm thick saddle so hopefully it will all work out. Mike.