cooktown ironwood fingerboards

[old_picker]

i have built 3 necks using this stuff and had problems with the first two - the 3rd is as yet unfretted and uncut
both finished necks have exhibited back bow after fretting - luckily the biflex truss rod installed in both bought them back to straight
have fretted any number of other necks and not seen this occur

on both i used a little tightbond scraped onto the fret tangs before pressing home
i usually do this to bed the frets in good - have also used CA gel which works pretty well

i would like to ensure that the 3rd neck comes up straight if possible - i doubt i would use it again even though it comes up real nice as a finger board

any body had this ?
any one got some advice?

[jeffhigh]

Only done one quite a few years ago and had no problems
Perhaps the extreme hardness of the wood is not letting the fret barbs embed into the end grain?
Perhaps using a slightly wider slot or dressing the tangs may help
I fret before installing the board now so this is never an issue.

[DarwinStrings]

Hi Ray, I have used it for 6 fret boards, never had a problem. I use epoxy to glue it to the neck now (used Titebond the first time and no problem), cut my fret slots as shallow as possible and don't glue my frets in. My fret wire matches my kerf (Stewy Mac saw and fret wire). Is it possible you might be gluing the bow in when you join?

Jim

[DarwinStrings]

I just re-read your post Ray, cancel that last sentence of mine.

Jim

[vandenboom]

I have done about 10 guitars with cooktown ironwood fretboards and experienced this problem early on.
I use the Stewmac table saw blade to cut fret slots and also have their fretwire.
I found the backbow was reduced by running a hand saw through the slots after the inital cut to make the fret slots a bit more generous.
Just in case if you haven't seen past threads on its use, I am mindful of of comments by some experienced builders (eg Gerard Gilet) who stopped using it simply because refrets are difficult with chipouts being hard to avoid when pulling out fretwire. While I love the look and finish of these cooktown ironwood fretboards, I wouldn't use it on a guitar for a serious player where a refret down the track is more likely. Most of my 'customers' are only occasional users so unlikely to be an issue in my lifetime.
Frank

[Allen]

I've found that this happens with a lot of Australian hardwoods that I use for fret boards. Never happens with Ebony or Indian Rosewood. I would say that it's caused by the extreme hardness of the material and there is no compression at all of the fibres when the fret is installed.

Whenever possible, I fret the board days, or even weeks ahead of needing it. I then clamp it to a 20mm thick piece of steel that I've had precision ground (for another job) and just let it sit. I've noticed that even after a couple of days that when I take the clamps off the board will sit almost flat. Whereas before there could have been considerable back bow.

[old_picker]

the last of the 3rd is still uncarved but fretted - i am thinking that i should clamp it up to introduce a bit of backbow before i carve it - i have one slotted board left that i will toss - just not worth the fiddle in my estimation

thanks for the info

[sebastiaan56]

I've never had a problem. I useEVO so the refret is deferred for a very long time. Since I got the slot width sorted out back bow hasn't been an issue. I believeGerard had concerns about potential sensitivities to Cooktown Ironwood. I've not experienced any issues.

[jeffhigh]

Evo seems to have smaller barbs than most other wires
Probably make a difference, certainly goes in easy.