| Pages:
1
..
4
5
6
7
8
..
15 |
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
I'll be careful!
then I will post the result.
thanks so much
|
|
|
Fritz
Oud Junkie
Posts: 246
Registered: 6-14-2012
Location: Northest Germany
Member Is Offline
|
|
Quote: Originally posted by faggiuols  | good morning to all!
An update from my work.
I am preparing the stage of gluing the ribs according to the method recommended by Jdowning.
in the photo the paper that I will use to close the ribs.
I also got the glue on the block as recommended by Jdowning.
|
Hi faggiuols
Glueing the neck block (and the other) is a good idea ! Because the hot glue bonds perfect on itself ! If soaked deep in the block, the fit will be
perfect when the ribs are pressed with the right amount of thicker glue. But... work fast, and keep in mind that all outsqueezing glue has to be wiped
away as soon as possible and as much as possible... as long as the glue is flexible...
The same with the ribs... apply enough thinner hot glue to the edges of the ribs to be glued, than heat up area for area beginning on one end to the
other in order to leave no glue unheated between the ribs ! An use a kind of metal clamps to pull the ribs together while heating...
Put a lamp under the glued ribs to look for through-shining light, there is not an exactly fit... Heat up again and on both sides a bit more of the
joint... to let the "environment" become hot and soft to make the fit exact. Switch the light of (if it´s a 100 wa9t lamp.. so it doesnt heat the
joints... :-)
Try the best :-)
Fritz
Music is the food for the soul
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: Originally posted by Fritz | | Quote: Originally posted by faggiuols | good morning to all!
An update from my work.
I am preparing the stage of gluing the ribs according to the method recommended by Jdowning.
in the photo the paper that I will use to close the ribs.
I also got the glue on the block as recommended by Jdowning.
|
Hi faggiuols
Glueing the neck block (and the other) is a good idea ! Because the hot glue bonds perfect on itself ! If soaked deep in the block, the fit will be
perfect when the ribs are pressed with the right amount of thicker glue. But... work fast, and keep in mind that all outsqueezing glue has to be wiped
away as soon as possible and as much as possible... as long as the glue is flexible...
The same with the ribs... apply enough thinner hot glue to the edges of the ribs to be glued, than heat up area for area beginning on one end to the
other in order to leave no glue unheated between the ribs ! An use a kind of metal clamps to pull the ribs together while heating...
Put a lamp under the glued ribs to look for through-shining light, there is not an exactly fit... Heat up again and on both sides a bit more of the
joint... to let the "environment" become hot and soft to make the fit exact. Switch the light of (if it´s a 100 wa9t lamp.. so it doesnt heat the
joints... :-)
Try the best :-)
Fritz |
thanks Fritz
for advice.
fantastic idea that the lamp under the ribs to ensure it is a coincidence between the bonding surfaces of the ribs.
Now I will try with the second rib! let's see what happens!
thanks
and bye
|
|
|
jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
|
|
A more convenient tool for working with hot hide glue joints is a temperature controlled mini electric iron. This is the one that I use purchased from
a local hobby shop. It is used for sealing plastic film on model aircraft. They are also available from luthier supply shops at about twice the
price.
For this tool I set the thermostat to the half way position - the setting that works for the glued paper technique. At this setting the temperature is
about 90°C to100°C the boiling point of water. So the temperature is correct when a drop of water on the hot surface of the iron will take a second
or two to immediately 'fizzle' and evaporate into steam.
The ideal temperature for maintaining hide glue as a liquid is about 60°C, however, the iron in use is always kept moving over the joints first to
re-liquify the glue (seen to melt) and then to set the glued paper strips in place. The paper insulates the joint underneath against over heating. At
the same time the iron cools down before regaining temperature so everything balances out just fine in practice.
When the iron is used to re-liquify a sound board to bowl joint the temperature of the iron is set a bit higher as the thickness of the sound board
wood slows down the heat penetration.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: Originally posted by jdowning | A more convenient tool for working with hot hide glue joints is a temperature controlled mini electric iron. This is the one that I use purchased from
a local hobby shop. It is used for sealing plastic film on model aircraft. They are also available from luthier supply shops at about twice the
price.
For this tool I set the thermostat to the half way position - the setting that works for the glued paper technique. At this setting the temperature is
about 90°C to100°C the boiling point of water. So the temperature is correct when a drop of water on the hot surface of the iron will take a second
or two to immediately 'fizzle' and evaporate into steam.
The ideal temperature for maintaining hide glue as a liquid is about 60°C, however, the iron in use is always kept moving over the joints first to
re-liquify the glue (seen to melt) and then to set the glued paper strips in place. The paper insulates the joint underneath against over heating. At
the same time the iron cools down before regaining temperature so everything balances out just fine in practice.
When the iron is used to re-liquify a sound board to bowl joint the temperature of the iron is set a bit higher as the thickness of the sound board
wood slows down the heat penetration. |
hello Jdowning.
I looked for this item in the shops in the area are not able to find it!
I took an iron at a good price, I also need to iran the ribs before assembly.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
I mounted the second rib and here's the result.
the thread of Maple may not be perfect and may need to redo everything if the white line should not be visible along the entire bonding surface.
hours prefer to immediately remove the glue to see the result.
if everything is ok continuous with the other ribs.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
the technique is mixed!
I have used both the tape, for the first fixing, the glue paper to tighten the joint.
overall I think it went pretty well except for the fact that at one point the white line does not seem very visible. I hope that the maple emerges
well after sanding!
|
|
|
jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
|
|
If you need to force the ribs together with tape and pins then you are not using the glued paper technique correctly.
The ribs should first fit the mold and fit together perfectly without having to be forced in place.
There are insufficient paper strips applied along the rib joint if you are working along the joint bit by bit remelting the glue in the joint and
applying the strips as you go.
There should not be excess glue squeezing out from under the paper strips. Are you applying glue to the rib surface as well as the paper strips? It is
only necessary to pre-glue the paper strips with a uniform thin layer of glue applied at the correct temperature.
The paper strips do not appear to be in tight contact with the ribs - so likely not ironed on smoothly at the correct temperature or there is way too
much glue under the paper. Either way the glued strips will not work as intended.
When gluing the ribs together it is only necessary to support the opposite rib against lateral movement with pins (or small wooden blocks) during the
gluing operation.
Here is how it should look. It is an easy technique to apply - just takes a little practice
[file]33447[/file]
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: Originally posted by jdowning | If you need to force the ribs together with tape and pins then you are not using the glued paper technique correctly.
The ribs should first fit the mold and fit together perfectly without having to be forced in place.
There are insufficient paper strips applied along the rib joint if you are working along the joint bit by bit remelting the glue in the joint and
applying the strips as you go.
There should not be excess glue squeezing out from under the paper strips. Are you applying glue to the rib surface as well as the paper strips? It is
only necessary to pre-glue the paper strips with a uniform thin layer of glue applied at the correct temperature.
The paper strips do not appear to be in tight contact with the ribs - so likely not ironed on smoothly at the correct temperature or there is way too
much glue under the paper. Either way the glued strips will not work as intended.
When gluing the ribs together it is only necessary to support the opposite rib against lateral movement with pins (or small wooden blocks) during the
gluing operation.
Here is how it should look. It is an easy technique to apply - just takes a little practice
|
Good morning, Jdowning
the strips of tape I used for the first positioning of the rib adjacent to the one already glued. then free spaces I put the glue paper.
the glue comes out from the sides of the paper during the burn. I think I put too much glue in the paper (I am attaching a photo).
after the first glue escape from the paper glue the procedure was corrected, and the paper adhered well to the rib.
unfortunately the ribs were not perfect, partly because the first one, already glued, had been reduced in thickness up to 2.2 mm, while all the other
I have not polished before assembly and are 2.8 mm. thickness.
the difference of 0.6 mm. created a bit more difficult.
I hope with the next that the procedure is easier.
a question: the glue paper retires immediately with the consequent closing of the ribs, or the withdrawal is slower and takes a few hours? in your
argument which explains well the technique, I have not read this detail.
also how long I have to burn the glue paper?
in the next few days I will try the rib 3 and try to be more attentive to the procedure.
thanks a lot Jdowning
|
|
|
SamirCanada
Moderator
Posts: 3404
Registered: 6-4-2004
Member Is Offline
|
|
hi my friend.
looking at this picture, it appears there is a gap between rib and white wood strips,
use a flash light under to see if the light comes through. if any lights comes through it means you do not have a good joint.
there can be a 2 reasons
1- the glue in between wasn't fully softened before you pulled the ribs together. This area should be reheated with some moisture and perhaps some
more glue and pull it together once again.
or
2- the ribs and separating strip do not fit, which means they are not shaped to the exact same profile and angle. you have to shape each rib exactly
the same on the inverted plane or sandpaper which ever you use so that before you glue them there is no light coming through if you use a flashlight
under it.
it would help to lightly pull through your strip on a light sand paper to clean up the jagged edges.
keep going don't give up!
@samiroud Instagram
samiroudmaker@gmail.com
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: Originally posted by SamirCanada | hi my friend.
looking at this picture, it appears there is a gap between rib and white wood strips,
use a flash light under to see if the light comes through. if any lights comes through it means you do not have a good joint.
there can be a 2 reasons
1- the glue in between wasn't fully softened before you pulled the ribs together. This area should be reheated with some moisture and perhaps some
more glue and pull it together once again.
or
2- the ribs and separating strip do not fit, which means they are not shaped to the exact same profile and angle. you have to shape each rib exactly
the same on the inverted plane or sandpaper which ever you use so that before you glue them there is no light coming through if you use a flashlight
under it.
it would help to lightly pull through your strip on a light sand paper to clean up the jagged edges.
keep going don't give up!
|
thanks samir
also for the encouragement!
Now I check it okay if light passes.
I think, however, that it is a proper bonding.
the wire mapple is lower rib and creates a small shadow on the white thread.
in any case I will control better as you say!
as always thanks
|
|
|
jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
|
|
The glue coating on the paper is excessive.
Also pay attention to the grain direction of the paper strips - the direction of curl in the strips should be across the rib joint to take advantage
of the paper shrinkage (explained in the 'Old Oud - New Project' topic, link previously posted).
When you first apply glue to the rib joint surfaces it will cool and gel before the joint surfaces can be glued together. The joint must then be made
- inch by inch - by re-heating the glue in the joint until it is seen to melt, pushing the joint surfaces together, and then applying the glued paper
strips to hold the joint together. The paper strips are sealed in place with the hot iron. The sealing is immediate after which the hot iron should be
removed. Keep the iron moving at all times. Do not burn the paper with an iron that is too hot!
If you use adhesive tape to first temporarily hold the ribs together in position (it should not be necessary if the ribs fit well) then it will have
to be removed before that section of the rib joint can be properly glued together - as you work your way along the joint starting at the neck block
end.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
very clear Jdowning!
thanks
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: Originally posted by SamirCanada | hi my friend.
looking at this picture, it appears there is a gap between rib and white wood strips,
use a flash light under to see if the light comes through. if any lights comes through it means you do not have a good joint.
there can be a 2 reasons
1- the glue in between wasn't fully softened before you pulled the ribs together. This area should be reheated with some moisture and perhaps some
more glue and pull it together once again.
or
2- the ribs and separating strip do not fit, which means they are not shaped to the exact same profile and angle. you have to shape each rib exactly
the same on the inverted plane or sandpaper which ever you use so that before you glue them there is no light coming through if you use a flashlight
under it.
it would help to lightly pull through your strip on a light sand paper to clean up the jagged edges.
keep going don't give up!
|
hello Samir
with horror
I found that you had seen very well, light comes through between the ribs.
is something infinitesimal but it comes through!!!
what I have to do?
I have remedy or i must remove the ribs? I can heat the glue only at that point and tighten best the ribs?
thanks so much
|
|
|
SamirCanada
Moderator
Posts: 3404
Registered: 6-4-2004
Member Is Offline
|
|
that's unfortunate my friend but not all is lost. In most cases it can be rectified. Don't be so hard on yourself its your first oud!
if you use the light along the whole rib, is this only a small section where light comes through or is it along the whole rib? if its only a small
section it can be fixed. if its along the whole length of the rib, I would make a new rib that matches the first one.
So the first thing to do is in the future make sure the ribs match without light showing before you glue them.
to fix this situation, you can try to apply a bit of water or slightly diluted hot glue to that area and reheat the joint, once the glue gets warm
squeeze the joint together and see if it closes. If it does that's great news the joint will be ok.
if it doesn't close properly it means that your ribs don't match exactly, you can fill the gap with a mixture of rosewood dust and glue. you can make
that rosewood dust yourself using sandpaper from a piece of your own rosewood. the colour will match exactly that way.
don't sweat it too much, its common to find ouds where there are small gaps in the ribs but you don't want to have very many. Remember, at the end you
will apply paper soaked in hide glue from the inside and you will also fill those cracks with hide glue.
@samiroud Instagram
samiroudmaker@gmail.com
|
|
|
jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
|
|
If the gap is very fine - as it would seem to be - then the best plan would be to apply a little moisture, reheat the joint, press it together and
clamp until the glue has cured as Samir suggests. If the gap is very fine, however, you will not be able to work fresh hot hide glue into the joint
and it will not be drawn in by capilliary action either. This way you will just be reactivating the glue that you put into the joint originally which
is OK.
A great part of the strength of a finished bowl comes from the interior rib joint reinforcement anyway so a small dry joint area - while it should be
avoided - will not have disastrous consequences.
Note also that the varnish that is applied to finish a bowl also acts like an adhesive and most likely will soak into any fine cracks to fill and bond
them together in the absence of glue
Note that the reason for using contrasting coloured lines between the ribs is not just decorative but to disguise any slight irregularities in the rib
joints that would surely be evident without the lines. This makes the job of bowl making easier particularly in the case of bowls that are not of a
perfect semicircle in section (like most lute bowls) where every rib is of a different geometry to its neighbour.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
thanks Samir and Jdowning
tonight I try to take a picture in the light between the ribs and tomorrow I will post it.
unfortunately I do not know if under the paper there are other points where the light comes through, I do not think and I hope not.
visible is only a tiny point where the light comes through exactly where Samir saw.
thanks for your suggestions.
before I try to paste back the rib in that point by following your advice.
tonight I will work in my workshop and tomorrow i will post the results.
thanks a lot
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
here is the image. Unfortunately, the photo is very blurry.
seems a gap greater than it is.
I proceeded as follows.
-I wet the joint with a few drops of water;
- I warmed up the joint with iron;
then I looked to see if the light comes through and it seemed not.
then I put a piece of paper and glue I heated with iron.
if the operation went well I will see him when the bowl is over.
if it is not done well I will use the sawdust rosewood with glue!
hopefully good.
in any case still I'm studying a system to tighten the rib during the first placement.
in the images the light comes through before;
thanks
[file]33487[/file]
|
|
|
jdowning
Oud Junkie
Posts: 3485
Registered: 8-2-2006
Location: Ontario, Canada
Member Is Offline
Mood: No Mood
|
|
Glad it worked as planned - the fact that it can be reconstituted with moisture and heat is one important aspect of using hide glue when assembling an
instrument.
Note that shining a light behind a joint to identify any irregularities is a very severe test - it makes any slight discrepancy look a lot worse than
it really is. If you proceed to make each joint bit by bit seeing the glue remelt with heat application before pushing the joint faces together and
then holding the joint surfaces together until the glue has fully cured - by glued paper strips, adhesive tape or whatever - you should have no
trouble with dry, unglued joint sections irrespective of any slight irregularities (that would be filled with glue as part of the process).
It would have to be a huge flaw in a joint to allow filling with glue and rosewood sawdust!
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
| Quote: |
it makes any slight discrepancy look a lot worse than it really is
|
in fact if Samir did not notified me it, I would not have noticed the imperfection.
But in the future I will always use the lamp during the bonding of the ribs so that I can immediately see any errors before pasting definitely.
thanks for help
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
new update.
yesterday with a technical viewed on the internet, converted by my, I installed two new ribs.
bonding seems fine.
the technique is some pieces of wood tied down and pulled high by laces. better to see the photos that explain in words.
after stopping the rib in the right place I proceeded to paste glue paper.
all right!
only in a point positioning does not seem well executed.
some pictures ..
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
some other image.
I believe that the joint on the neck is defective for the presence of too much glue of the previous gluing of the rib 1.
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
Hello everyone!
an update on my work.
are always struggling with my oud ..
many difficulties, but the work draws to better.
I understood how to fit well the ribs!
the light does not come through.
here's some update image.
[file]33920[/file] [file]33922[/file]
|
|
|
faggiuols
Oud Junkie
Posts: 285
Registered: 9-10-2014
Location: cagliari sardegna italia
Member Is Offline
|
|
I started to clean the glue surface.
I know that it was wrong and that this work must be done at the end.
I was impatient.
could be a problem?
I think, however, that the work is coming along well!
|
|
|
Microber
Oud Junkie
Posts: 853
Registered: 1-20-2006
Location: Belgium - Liège
Member Is Offline
Mood: No Mood
|
|
Nice Faggiuols.
Thanks for sharing.
Robert
|
|
|
| Pages:
1
..
4
5
6
7
8
..
15 |
![[*]](images/xmbprobrown/default_icon.gif){kind=icon}
