Visible Glue Lines help please

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DavidRa

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Started this new hobby only a few months ago with the intention of making some small boxes as gifts . Practiced on meranti and some other softer woods and eventually got to a point where i knew what I had to do ( which is different from doing what I had to do :) ) and started making the box with American Black Walnut. Did my dovetails and dry fitting they seemed ok (ignoring my mistakes) and then did a glue-up using Titebond Original. Clamped the box using blocks to apply pressure to the joints but when i looked at the glued up box I have visible glue line which is disappointing. I didn't have this problem with meranti.

The intention is (was) to oil and then lacquer the box.

So the questions I have are
  1. what could I have done better on the glue up
  2. Was I using the right glue?
  3. Is there any way to hide the white glue lines which are visible on even good ( for me) joints
    1. Is it possible to dissolve the visible glue and then use other methods to disguise any gaps
    2. Cut it out but that does not seem an option when i tried with a scalpel
Any help would be appreciated

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DavidRa

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That's a thought as it was bitter yesterday when I did the glue up. Thanks
 

Doug71

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Titebond 2 is available in a dark version instead of the normal yellow, also titebond 3 dries a dark colour, both less obvious if using a dark coloured wood.

Careful gluing things together when it's cold, the glue can fail. Think Titebond 3 will work at a lower temp then Titebond 2.
 

Sgian Dubh

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Possible causes of visible glue line.
  1. Sockets between pins at an angle of less than 90º from the inside face of the board (short side) to the outside face of the board.
  2. Sockets between pins convex between inner face and outer face.
  3. The cut pins extended beyond outside face of the dovetailed board (long side) and applied pressure through wooden clamping blocks was concentrated on the end of the pins and not on the outside face of the dovetails.
Your glue type choice was fine, and I strongly suspect the problem is a mistake in the execution of the joint, as described above or perhaps some technical error I've missed, rather than the glue-up procedure. Having said that, I wouldn't normally apply clamps at all, preferring to simply use a hammer and small block of wood to assemble the joint during glue-up. Clamps can actually make things more challenging to achieve a satisfactory glue-up - they sometimes add unnecessary weight, fiddling and cumbersomeness to assembling small items like yours.

Hiding the glue lines is only likely to be partially successful, whatever you do. You could maybe try 'painting' them out as best you can using a little shellac, a very fine brush and a close matching brown pigment.

Apart from that, you may just have to accept the error(s), fixed as best you can, as a learning curve and move on to do better next time. We've all been there, but in my case I have to admit that my 'being there' was probably sometime back in the Neolithic period, or maybe a bit before that, ha, ha. Slainte.
 

DavidRa

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Possible causes of visible glue line.
  1. Sockets between pins at an angle of less than 90º from the inside face of the board (short side) to the outside face of the board.
  2. Sockets between pins convex between inner face and outer face.
  3. The cut pins extended beyond outside face of the dovetailed board (long side) and applied pressure through wooden clamping blocks was concentrated on the end of the pins and not on the outside face of the dovetails.
Your glue type choice was fine, and I strongly suspect the problem is a mistake in the execution of the joint, as described above or perhaps some technical error I've missed, rather than the glue-up procedure. Having said that, I wouldn't normally apply clamps at all, preferring to simply use a hammer and small block of wood to assemble the joint during glue-up. Clamps can actually make things more challenging to achieve a satisfactory glue-up - they sometimes add unnecessary weight, fiddling and cumbersomeness to assembling small items like yours.

Hiding the glue lines is only likely to be partially successful, whatever you do. You could maybe try 'painting' them out as best you can using a little shellac, a very fine brush and a close matching brown pigment.

Apart from that, you may just have to accept the error(s), fixed as best you can, as a learning curve and move on to do better next time. We've all been there, but in my case I have to admit that my 'being there' was probably sometime back in the Neolithic period, or maybe a bit before that, ha, ha. Slainte.
I suspect you are right on the execution, so will just have to try harder next time!
 

Cabinetman

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What Richard said got me thinking, please don’t think I’m being critical, it’s just that I'm thinking of doing a piece on basic marking out and I wondered if you wouldn’t mind explaining exactly how you marked out the shoulder lines for your joints, warts and all please! Thanks in anticipation Ian
 

DavidRa

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What Richard said got me thinking, please don’t think I’m being critical, it’s just that I'm thinking of doing a piece on basic marking out and I wondered if you wouldn’t mind explaining exactly how you marked out the shoulder lines for your joints, warts and all please! Thanks in anticipation Ian
Hi Cabinetman, no criticism taken and thanks for your, and others interest.

Basically tried to implement what i learnt from various You Tube resources, Paul Sellers, Matt Estlea, Katz Moses so using a knife wall to achieve as crisp an edge as i could and then paring away at the wood to get to the knife wall. I used a Veritas 1:8 dovetail guide for the marking out using a marking knife to score the lines.

On Richards points 1 & 2 I did check for 90 degrees across the end grain and ensured that the joint was not convex so I am thinking that his point 3 may be a contributor to the issue as looking at the work my main problem seems to be at the bottom edge of the joint. I also think I may have been a bit gung ho (with hindsight) with sanding the inside of the box before the glue up ( probably sanded over the pins) and think this may have caused some gaps which I did not see on the dry fit.

The initial wood was PAR but it had moved a bit so i planed and then hand sanded & shot and checked all squares before I started.

Reading this back , according to me I did everything right !!

In all seriousness I think I know where I can make changes to my technique for my next attempt but in the meantime I have somewhat disguised the errors using acetone to soften and remove the worst glue lines and then putty to get a colour match on any gaps. It looks okish , probably good enough so that a casual observer wouldn't notice but not what i wanted to achieve.

Cheers
 

DavidRa

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Titebond 2 is available in a dark version instead of the normal yellow, also titebond 3 dries a dark colour, both less obvious if using a dark coloured wood.

Careful gluing things together when it's cold, the glue can fail. Think Titebond 3 will work at a lower temp then Titebond 2.
Thanks, will try that next time
 

Cabinetman

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Thanks David, right back to basics though, did you mark up with face side and face edge? (Even though it sounds as if what you did was correct)
 

Peri

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Having an unheated workshop I found out that Titebond 3 is the lowest temp 'normal' woodglue you can use (9c/48f), all the other usual suspects cant be used below 13c/55f.

Temp in the UK hasn't been much above 4c/39f for around the last week - so if you have an unheated shop that might be a big part of the problem.

EDIT: Put the glue and two pieces of scrap in the living room for a few hours to acclimatize, do a glue up and see if the results are the same - if it's fine, you know it's a temperature problem.
 
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Ttrees

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Nice box David

Could this be an issue with the waste pushing the bevel with the walnut versus the meranti?
The walnut might need the "tenting" done with a bit more care.
Along with Charlesworth, Derek Cohen's videos mention this.
I haven't cut many dovetails, so am not a good person to give you tips on the best practice... i.e speed.

From experience of very slowly plugging timbers without minute gaps throughout,
I will mention that every video I have ever watched on dovetails, I don't recall any of them mention checking the edge.
I don't mean for square, but placing the chisel on the baseline and seeing if you could theoretically fit a hair or feeler gauge inbetween.

Quite visible by eye, no tools required apart from the chisel with flat back and an good light source.
See the big gap inbetween the plate and the mortise wall, could nearly fit an envelope through there on the right side.
It all looks very uniform, so am guessing that's the reason.
Very easy to do on end grain.(sorry I have no photos, but the same thing using a chisel)


Now one for the experienced, can it be swollen tight with an iron and some moisture (damp rag), if the heavy line of glue was removed?
Best ways to do so... using the tip of the iron and a pin?


Tom
 

Bristol_Rob

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Titebond 2 is available in a dark version instead of the normal yellow, also titebond 3 dries a dark colour, both less obvious if using a dark coloured wood.

Careful gluing things together when it's cold, the glue can fail. Think Titebond 3 will work at a lower temp then Titebond 2.
This was my thoughts and why I have a bottle
 

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DavidRa

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Nice box David

Could this be an issue with the waste pushing the bevel with the walnut versus the meranti?
The walnut might need the "tenting" done with a bit more care.
Along with Charlesworth, Derek Cohen's videos mention this.
I haven't cut many dovetails, so am not a good person to give you tips on the best practice... i.e speed.

From experience of very slowly plugging timbers without minute gaps throughout,
I will mention that every video I have ever watched on dovetails, I don't recall any of them mention checking the edge.
I don't mean for square, but placing the chisel on the baseline and seeing if you could theoretically fit a hair or feeler gauge inbetween.

Quite visible by eye, no tools required apart from the chisel with flat back and an good light source.
See the big gap inbetween the plate and the mortise wall, could nearly fit an envelope through there on the right side.
It all looks very uniform, so am guessing that's the reason.
Very easy to do on end grain.(sorry I have no photos, but the same thing using a chisel)


Now one for the experienced, can it be swollen tight with an iron and some moisture (damp rag), if the heavy line of glue was removed?
Best ways to do so... using the tip of the iron and a pin?


Tom
Thanks, I've decided it's my poor technique that caused the problem which is possibly why i failed my O level woodwork ( yes i am that old) twice!
 

ztifpatrick

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A glue joint that visible is probably down to a less than perfect fit, as mentioned above, or poor clamping pressure, but titebond original is a very yellow glue, especially against walnut. You can tint titebond, but as mentioned titebond 3 would be a better colour and better temp glue. However, pva glues like titebond tend to "lockup" during assembly of tite joints. Titebond also make a liquid hide glue, which is slippery and the colour would be good on walnut. Overall a decent attempt for a newbie, don't get too discouraged, soldier on!
 

recipio

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The cutoff temp for all of the PVAs seems to be about 6 C. It looks like 'chalking' of the glue due to the cold is your problem. In practice you should not see a glue line after glue up --- easier said than done. Using painters tape along the line will help. I tend to wait 40 mins after glue up by which time the glue will be 'rubbery' and should peel off. Interestingly Titebond have a new glue out ( Titebond Speedset ) which will glow violet under a UV light. It sets very fast however.
 
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