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  #1  
Old 02-21-2017, 04:33 PM
SnowManSnow SnowManSnow is offline
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Default Why can I see braces through the finish?

I'm trying the stewmac nitro cans and.... this ....
What's going on? I'm only about half through the process of laying down finish coats

At this point do I need to let this dry 24 hours and try and proceed?


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Old 02-21-2017, 04:37 PM
SnowManSnow SnowManSnow is offline
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It was proceeded by sanding sealer like instructions state.


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Old 02-21-2017, 04:59 PM
SnowManSnow SnowManSnow is offline
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Perhaps it's having a harder time evaporating off where the glue is.
This was pretty close to after spraying


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Old 02-21-2017, 05:26 PM
mirwa mirwa is offline
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Approximately what thickness is the back, what type of glue did you use for clamping the braces down

Steve
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Old 02-21-2017, 05:29 PM
Frank Ford Frank Ford is offline
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I've always taken it as a temperature/humidity thing - as the lacquer solvents flash off the unbraced section cools faster and a slight blush can appear there. In my shop and experience, that effect hasn't been a bother for subsequent coats or had an influence on the final finish.
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Old 02-21-2017, 05:35 PM
SnowManSnow SnowManSnow is offline
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Quote:
Originally Posted by mirwa View Post
Approximately what thickness is the back, what type of glue did you use for clamping the braces down

Steve


Hey I used fish glue for the braces.
The back is .09ish I THINK.
If I remember right


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Old 02-21-2017, 05:36 PM
SnowManSnow SnowManSnow is offline
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Quote:
Originally Posted by Frank Ford View Post
I've always taken it as a temperature/humidity thing - as the lacquer solvents flash off the unbraced section cools faster and a slight blush can appear there. In my shop and experience, that effect hasn't been a bother for subsequent coats or had an influence on the final finish.


You know it COULD be a humidity issue
It's very humid here and it was out in that a bit today while I sprayed.
I have moved it inside to the controlled area....


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Old 02-21-2017, 06:28 PM
mirwa mirwa is offline
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Are these marks remaining after spraying example an hr later, or only appearing during the spraying process or directly after the spraying process.

If they appear as you are spraying, then its likely that it needs more of a sealer laid down first and not so heavy coats applied.

If they appear 5-10 minutes after spraying then they are likely to do with temperature of the wood, areas where they are coupled with braces are thicker and take longer to change temperature, example from being sprayed.

If they appear after an hr and stay, then its likely the fish glue has penetrated rather deeply into the back, you likely will need to lay down another sealer coat or two first, or change sealer coats to somehting that does not get softened by subsequent coats of nitro.

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Old 02-21-2017, 07:38 PM
SnowManSnow SnowManSnow is offline
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Quote:
Originally Posted by mirwa View Post
Are these marks remaining after spraying example an hr later, or only appearing during the spraying process or directly after the spraying process.

If they appear as you are spraying, then its likely that it needs more of a sealer laid down first and not so heavy coats applied.

If they appear 5-10 minutes after spraying then they are likely to do with temperature of the wood, areas where they are coupled with braces are thicker and take longer to change temperature, example from being sprayed.

If they appear after an hr and stay, then its likely the fish glue has penetrated rather deeply into the back, you likely will need to lay down another sealer coat or two first, or change sealer coats to somehting that does not get softened by subsequent coats of nitro.

Steve
its the sealer that came WITH the nitro in a stewmac finishing kit.. and a few hours later the marks are still there.
I'm going to try and do a very light mist in a few areas and see if it is just that coat?I'm not sure why the glue would penetrate that deeply... very strange.
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Old 02-21-2017, 07:46 PM
Truckjohn Truckjohn is offline
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It looks to me like it's too warm and your lacquer isn't flowing out right. Do you have any way to spray outdoors or in a place that's cooler - like low 60's?

Next - don't spray very light coats using a rattle can. That's a recipe for a huge dog mess. You have to spray an evenly "wet" looking coat that doesn't sag..
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Old 02-21-2017, 08:18 PM
SnowManSnow SnowManSnow is offline
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Quote:
Originally Posted by Truckjohn View Post
It looks to me like it's too warm and your lacquer isn't flowing out right. Do you have any way to spray outdoors or in a place that's cooler - like low 60's?

Next - don't spray very light coats using a rattle can. That's a recipe for a huge dog mess. You have to spray an evenly "wet" looking coat that doesn't sag..
ok. thanks for the advice....
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  #12  
Old 02-21-2017, 08:25 PM
SnowManSnow SnowManSnow is offline
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Well... now it's gone. ... after a coat.


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  #13  
Old 02-21-2017, 08:26 PM
SnowManSnow SnowManSnow is offline
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  #14  
Old 02-21-2017, 08:55 PM
mirwa mirwa is offline
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Yeh, I do not think we needed that photo, you just cannot unsee some things.

Quote:
Originally Posted by SnowManSnow View Post
I'm not sure why the glue would penetrate that deeply... very strange.
Glue wicks down through the grains (its what we want for good adhesion) a porous wood like mahogany wicks further than it would on say maple.

Quote:
Originally Posted by SnowManSnow View Post
Well... now it's gone. ... after a coat.
Excellent, could be weather- temperature of the surface and air around it, or the nitro being sprayed is starting to form a sealer coat in the grain.

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  #15  
Old 02-21-2017, 09:25 PM
runamuck runamuck is offline
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The hazy blush is not from glue - it's from humidity. Either use a retarder or spray when it's less humid. The blush will probably go away but if it doesn't try shooting a straight coat of lacquer thinner on it.
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