Wednesday, 29 May 2013

Sanding veneer panels

Began with sanding the drawer divisions. Before I started to sand them I needed to remove the brads so they would not rip the sanding discs on th orbital sander.

I began with 180 grit. Normally you would start with 240 grit but the 180 wasn't that bad. With this you just don't want to stay in one spot for too long. The 180 grit is mainly to get rid of the dried polyurethane that has risen to the top surface of the veneer and also the adhesive from the painters tape.

When coming to do 240 grit I will do this by hand. I will only hit the parts with 320 grit when I have done most of the handling (cutting and other forms of machining) Before oiling I will buff the surface with a white cotton rag to get it smooth.

I might by a different type of sander paper disc since these ones don't last that long since they clog up really fast.

Its a little hard at some times to see whether I have gotten rid of all the risen polyurethane. It tends to blend in with the fiddle back really easily. Often I have to get a rag with some methylated spirits and wipe the surface to see if the surface is clean.

It is best to use methylated spirits because it drys fast and wont effect the surface.

I have only sanded the figured maple sides for the drawer divisions, the fronts of the drawer boxes, backs and sides. Before sanding the wenge I need to remove the tape with my card scrapers.

Clogged up sand paper discs.

So the parts don't get further damaged I rap them up in cloths and place them into a container.

Most of the other parts wont fit into this but will still go in between clothes and get placed in an area where there is not much traffic in my work shop.

Methylated spirits great to see if surfaces still need more work on them to clean them.

Sanding the wenge sides with 180 grit. Before sanding them found removing the old painters tape off with a .6mm cabinet scraper made things a lot easier.

The wenge is a lot more brittle than the maple so needed to make sure not to stay in one place for too long.

Removing old painters tape.

Progress of sanding wenge veneer faces for drawer fronts, sides and backs.

After all the 180 disc sanding was done began hand sanding all the parts with 240 grit. After sanding them buffed them with a white cotton rag shaped in a bun. When all the parts are finished and are ready for oiling I will hit them with 320 grit sanding than probably 400 grit than do the buffing again.

Tilted parts in the light to see if there were still scratches or adhesive marks. while sanding had to apply some methylated spirits to some parts. Due to the grain structure of the wenge its hard to see if the polyurethane is still there. It doesn't matter that much since the polyurethane melds well with the oils.

Sanding down the wenge faces for the drawer box bases. I had to remove the bulk of the polyurethane and the veneer tape and painters tape with the card scrapers before using the orbital sander. This is because the polyurethane clogs up the discs quick quickly.

After sanding the wenge faces with a 180 git on the orbital sander I applied a 240 grit to it by hand sanding it in the grain direction.

You can probably not see it in this picture but what has happen is that the dark brown layers from the plywood has shown up through the veneer. From an eariler post I had to sand down the plywood for the drawer box bases. Since going through the top good layers than getting into the middle they produced very poor faces revealing dark lines and spots every where. At the time I did not think this would matter......... well until now.

Seems like I was doomed from the beginning. Sadly I can not leave this like this. I want to keep this same book matching and sadly there is not enough veneer to get to exact book match as it was used up for other things. One of the other panels shows some of the dark brown sections but only a little bit but it is still noticeable.

In another earlier post how I talked about one of my work mates saying I should remove the pencil and texture marks as it would show up under the veneer when pressed, well now I know what he meant.

These sections are at the bottom of the drawer boxes but you will still see it when you turn over the box.

What I might do is add some sakura inlay and just enhance the design a bit. It just means if I do it for this one I have to do it to the rest as if I only do it to this one it will look like I'm trying to hide something.

I don't want to also had heaps of inlay work as like my dad said when he was at trade school for cooking adding too much garnish to a plate can seem like your trying to hide something.

I wont be able to hide the whole thing but I'll be able to cover up most of it. Since the inlay will be dark red and browns it will really take the attention away from the areas that are still visible.

Since I'm also having a red stringy inlay down the middle I have decided to incorporate the sakura inlay in with it. I had thought about using dark red timber on one side for the sakura leaves but when the flower sections cross into the other section ( veneer section on the other side of the red stringy inlay) it would change to white. This this still in planing stage and will only be carried out if I have time. If I dont have time I will replace both of the veneer bases by placing another booked matched section of figured maple.

I had to sharpen my card scrapers a few times since they got blunt very quickly. I placed my water stones in a tub of water so they would absorb the water. At the moment I only have a 400, 1000 and 2000 grit stone. I would like to get a 4000 grit to make the card scrapers even sharper. 

I found with using the card scrapers on the figuered maple a .4mm or a .6mm was a lot better. Where I found a .8mm was a lot better on the wenge.

When sanding the figuered maple for the drawer bases I did not want to take off too much because there could be a chance of going too deep and high lighting the dark sections from the plywood. So I decided to go to a 240 grit straight away instead of using a 180 grit.

Needed to keep checking the faces of the wenge with the methylated spirits to see if the polyurethane patches were showing up. Once you get the bulk off from sanding its hard to tell if little bits are still there due to it blending in with the grain.

My work shop does not have the best lighting and I think its best I get a work bench lamp now especially when it comes to oiling and fine sanding also waxing.

Its not a good picture but this is roughly something I would do with the sakura inlay to try and hide most of the dark brown patches from the plywood. This is not the design I have picked this was roughly to see what it would look like.

I will not transfer the designs onto it until the offsets are taken away and the drawer slips are added to it.

Also this inlay will only be added if I have time like I stated earlier. If I don't have time I will be veneering over again along with the other one that just had a little bit showing through.

The inlay designs will be a bit more detailed than this and more though out.

I will be doing some research on sakura inlay designs also plum flower designs. I would like this type of inlay to match a bit with the inlay on the wenge sections.

With the cold weather we have been having found one of the drawer box lids like this.

What has happened is that the moisture from the air has gone through the cell pockets of the veneer and started to build up air in the vacant area. There is a vacant area because the joint has failed in bonding due to being starved. So the veneer is really just sitting on the substrate face. The more air that has come in starts to create a bubble. It was probably best I saw this happen now instead of seeing it happen when its oiled.

This was the drawer box lid that I decided to hope for the best when this one and another one did not bond properly due to the glue joints being starved from not having enough glue applied to them.

Looks like it has come back to haunt me.

There were a few choices I could slice the bubbled sections and try and fit some glue into them, spread the glue out with a veneer hammer than hot iron it or try and remove the whole veneer section.

I tried slicing the bubbles and adding glue in ( which I should not have done, will talk about this later down the track)

I sliced the bubbled sections and placed some glue int there. It was quite hard to try and get glue in there. I used a my japanese knife and tweezers to open up the slit and used a small brush and brushed some tight bond 3 inside. This did not work that well.

I used the hammer to tap the file into the slit to try and open it up more.

I decided this was no good and decided on carefully removing the whole veneer from the substrate face. I didn't want to just rip it off and book match a new piece because I didn't have any more veneer that could do this particular book match. It would look silly if I had 3 drawer box lids matching in book match and one that didnt.

I used a card scraper for a bit taping it with a hammer very carefully to try and break the weak bond of the glue from the veneer and the plywood.

Some of the smaller sections I had to use a file to make opens larger. Found also a small 150mm ruler worked well as well.

When I had enough room I also ended up using a pastry spatula. With this you want to try and use it in a sliding motion to break away the old dry weak glue from the veneer and plywood. Some of the other tools I used were old sewing tools that my mum had.

I was able to remove the whole veneer piece from the substrate. Some of the veneer sections broke off but this was in the offset area so I wasn't bothered by it.

I needed to repair the splits that occurred when trying to remove the veneer from the plywood. Also the slits that I made from the Japanese knife. To close up these spots I used veneer tape.

Needed to remove the old dry glue from the panel before applying the new glue in the press up. Just used the orbital sander with a 120 grit pad.

Started to clean up the other drawer box lids. I found cleaning up the wenge face worked better first than the Figured maple face. This is because the wenge dust tends to stain the maple veneer. The dust gets into the poors and is annoying to get out. My dust collector system on my sander is not that good and needs to be replaced.

Removed most of the polyurethane and veneer tape so it would not clog up the discs as much. Although the polyurethane tends to blunted the card scrapers a bit.

Cleaning the maple faces. The same as the wenge used card scrapers to clean most of the polyurethane and veneer tape off.  Found applying moisture to the tape helped to remove it easier. Although needed to use distilled water from the spray bottle.

Cleaning the top panel. Removing the veneer tape from the bottom and sanding the faces.

Also sanded top section.

Started off with 180 grit on the orbital sander than moved down to 240 grit by hand.

Same as the wenge face started off with 180 grit than moved to 240 grit. Also buff the faces with a white cotton cloth.

Sanding the faces of the top carcass panel. Started off sanding the figured maple face.

Not the best picture but shows some of the black sections from the plywood showing up through the veneer. Again not bothered by this since this section will not be seen really at all. Place there will be a lot of shadows on it making it hard to spot.

Sanding the other face. Now this face does not get seen at all. Veneer is merely just added to this face to keep the panel structurally balanced.

Sanding the drawer box lid that needed to have the figured maple veneer re glued to it.

Sanded the figured maple veneer.

Not the best picture but this shows the slits that I made from the Japanese knife when they were bubbles. I should not have done this especially in a straight line. If I was to do it next time should have done it in a curve. This would make it a lot easier to blend in with inks and colored pencil when finishing.

Also should have tried to close up the slits before gluing the veneer to the substrate.

How this can be done is by applying moisture to both faces from some paper towel and pressing it over the slit with a block and clamp. What this is doing is expanding the timber by putting more moisture into the cells. This may needed to have been done a few times to minimize the slit.

I tried using the card scraper to try and get rid most of it and not make it look so dominate. The other slits are more hidden and some of them will be cut out as they are either located in the offset sections or located in the diamond housing sections. Unfortunately this slit is not located in the diamond housing section.

What I might have to do is do some coloring to it to make it more hidden when it comes to finishing. But it's most likely that this defect will be seen when the final piece is done. The bottom slit I should be able to blend in with inks and pencils.

Cleaning back door panels and front door flaps.  

To get a better result cleaning off the veneer tape. Wetting the panels with distilled water from a spray bottle works. It helps to break down the adhesive of the tape. Leave it for a couple of minutes than remove with card scrapers. You don't need to flood the panel with water just enough to break down the tape.

Most of the tape is removed and the left over stuff can be sanded off. I needed to let the panels dry from the water before sanding.

Did the same process to the top front door flaps as to the backs with removing the veneer tape.

Began cleaning the maple sides while waiting for the wenge to dry. Before doing the major cleaning some dints had to be repaired.

Cool trick to remove dints with veneer is using a syringe filled with mentholated spirits. You want to drop a few drops of it into the dint than light it up. This will cause the veneer to expand up. Depending on the dint this can take a few times. If the dint is in the substrate than steaming with a damp rag and an hot iron may need to be taken into account.

As for this dint it took a few times to get it out. In between the raising scraping back with the cabinet scraper took place was well.

I wanted to remove most of the polyurethane from the panels with the orbital sander first. This glue blunts the scrapers really quickly. The scraping was mainly used to get rid of the adhesive marks from the blue painters tape. The adhesive marks from this tape takes a while to get rid of.

Once all the sanding was down with the orbital sander hand sanding took over. I used 240 grit for this.

Checking to see if adhesive marks were still there on the panel with a damp rag placed in mentholated spirits was used.

Wenge faces cleaned with orbital sander at 180 grit than hand sanded with 240 grit.

Sanded down the top front door flaps with 180 grit on orbital sander than hand sanded with 240 grit.

After the 240 grit hand sanding is done buffing with a white cotton rag is done to remove dust and create a smooth surface.

Cleaning the maple sides for the top fold flap sections for the front door flaps. Knocked the brads in to they would not damage sander.

180 grit sanding with orbital sander than 240 grit hand sanding.

Had some more dints to repair and required using the mentholated spirits trick.

Removing the painters tape from the bottom front folding flaps. Just used a card scraper for this.

Wet surface to break down veneer tape adhesive making it easier to remove tape.

Most of tape remove the rest of it will be sanded off.

Sanding the bulk of the mess off with 180 grit sand paper on the orbital sander. Than 240 grit hand sanding.

Sanding the bulk off with 180 grit on orbital sander. Than 240 grit hand sanding. Once bulk of mess was removed used card scrapers.

The adhesive from the blue painters tape takes a long while to take off. I have found that its a lot harder to take off when left on for long periods of time. These panels were left in the press at tafe for 2 weeks due to the holiday break. So clean up took a bit longer.

Removing the painters tape from the veneered panel of the cabinet base.

It took awhile to remove the painters tape adhesive marks from the veneer. Some of this tape had been left on for a while. I had to remove a lot of the marks with the orbital sander using 180 grit. After most of it was gone I than used the card scrapers to remove the rest of the adhesive marks. The dried polyurethane blunts the scrapers very quickly so removing most of the dry polyurethane with the sander first prevents me from having to keep on sharpening the scrapers heaps. After cleaning with the scrapers I went back to sanding to get rid of any card scraper marks I did this with 180 grit sand paper discs.

After sanding was done with the orbital sander I used 240 grit to get a smoother finish than I buffed with a white cotton rag to get a smoother finish.

Removing the painters tape from the ikebana base panel and the top drawer base panel with the hot iron and card scrapers. Removed the tape before sanding commenced.

Began sanding the ikebana base panel and the top drawer base panel. Started off using 180 grit on the orbital sander. It really is a process of sanding than using the card scraper you want to sand off as much of the polyurethane as possible since the polyurethane blunts the hell out of the card scrapers.

Once all the adhesive marks are gone from the tape and patches of grim and polyurethane it is time to sand with the 240 grit by hand. After that buffing with the white cotton rag is done.

Testing with a rag with mentholated spirits to check areas still needed to happen to make sure adhesive marks were taken away. I also tilted the panels into the light where I could see if there were any adhesive marks left as well.

Unfortunately there was a dark spot on the counter veneer and it showed up. Luckily the spot was at the back. Even though you can sort of see this it will be less noticeable when the sides and tops are added to it as it will create shadows and less light will be going onto it. I did not want to flip over and use the other sides since I really liked this book matching more than the other side.

I had thought about using this as the top drawer base panel but the other panel has some little gaps in the veneer joints which I would rather have at the top. Most of the gaps will be taken out in the 20mm offset removal.

Now the panels were sanded they are ready to have the 20mm offset taken off them.

These sides were a lot easier to clean since the tape had not been on the veneer that long compared to the other sides. I think in the future when using the blue painters tape on veneer it will be best to sand it straight away when taken off.

Removing the blue painters tape from the maple veneer faces on the sides with the hot iron and card scrapers.

Both faces have the blue tape removed. Before sanding the wenge on the other side needs to have the veneer tape removed, after this the sanding process can begin.

Removing the veneer tape from the wenge on the sides. This required me to sprayer distilled water onto the veneer faces to soften the adhesive of the veneer tape which when softened I would be cleaning it off with the card scrapers.

Now dry was ready to sand and clean up with the cabinet scrapers.

Ages ago I mentioned I would have this problem. The wenge for the sides were the first panels that I pressed up. The glue I used was tight bond 1. Which is just a PVA wood working glue. Now I mentioned that I was going to see bleed through from the vein pockets and it may be really hard to clean up.

When water is placed on it the pockets reveal whites spots right across the whole board. This is way too hard to clean up since there are heaps of little cavietys every where. This is one of the reasons why you should used polyurethane for porous veneers since it does not show up due to not having any solvents. I used polyurethane for all the other panels.

Now when I put the oil onto the panels the white spots wont look like this but they will still show up. When placed in the light they will look like little plastic puddles, which again I can not have this especially on the sides. Now some of the sections will be cut out from the inlay but the other sections will still show the dried bleed through PVA.

You can not really get sand paper into the cavietys. Also you don't want to use anything too abrasive since it will blow through the veneer or really damage it with scratches.

Too break down the PVA from the cavietys I read some where that PVA glue can be broken down with iced cold water with a brush, but this was for PVA in clothes. I was thinking maybe this would work for the veneer.

Unfortunately this did not work. I tried other options like this eucalyptus liquid that breaks down adhesives I also tried other chemicals that break down solvent products. I only tested this on small sections of the panel mainly in the corners. This did not really work either.

I also tried cleaning with steel wool, kitchen scourers ( the sponge ones with the green soft scourer material) tooth brushes. I even tired cleaning out the individual cavity with a small blade also small picks. Unfortunately none of these worked.

 I looked up on line to see if people had ideas to solve this. Mainly I only came across options that would prevent this from happening not to fix it if it already happened. Most of the feed back suggested to just veneer over it which is what I'm thinking I'm going to have to do. People suggested to remove the veneer first but this really only counts if its a different veneer or if the veneer has had a finished applied over it. Placing wenge over wenge wont matter. All I have to do is just sand most of the crap off the panels so the glue bond will become stronger.

This has been an expensive mistake and has set me back about a week. Although to further learn mistakes must be made. You will never learn if you don't make mistakes. Lucky I have heaps of wenge veneer left over. For next time I deffently know now not to use solvent glues for wenge. It seems like polyurethane is the best glue for this veneer since even if there is bleed through it melds well with stains and oils and will not show up.

I don't really want to use more veneer but it has to be done. I don't want to apply oil over this and have these bleed through sections showing up. Better to fix it now instead of having a very poor result further down the track where I might not be able to fix.

I wont bother sanding the maple faces until the new layer of wenge is placed over the old faces. Dont want to do double handling plus if I sand it now there is a chance that scratches and other smudges may occur when handling it in the press up.

I did not end up applying the new layer to the wenge panel. Talked with my teachers for some advice. With the amount of inlay and other details the risen glue should not be seen that much. Also adding a new layer to the panel would make the panel un balanced.

Sanding the maple faces with the orbital sander at 180 grit.

Now for the wonderful unfortunate mistake which don't ask me how this happened since I was totally surprised about this. Some sections of the blue tape from one of the veneer joints was left under the veneer. You can really see this badly. I know never to place veneer tape under the joint so I really don't know how this happened.

These are not the chosen images of the flowers but just an idea. They would mainly need to cover the blue tape sections that have come through the veneer.

I can not afford applying veneer back over it or removing the veneer and applying another layer over it as I would need to do it to the other side due to both the sides book matching. I'm going to have to expand the flower inlay and do some here as well. I don't want to do too much compared to the outside since the main attention is the Ikebana arrangement. Although I have talked about it being used as a kodo (way of incense) cabinet.

I had thought about doing small Japanese balloon flowers in here. I don't want to add pics of flowers too much here or really at all since it would go against one of the Japanese principals I talked about earlier in one of the starting posts. But this stupid mistake needs to be fixed.

Japanese balloon flower. I would be making the inlay pics of them opened and probably closed.

The reason for Japanese balloon flowers is mainly due to it connecting with the name of the piece ' four seasons' plus I reckon a blue colour would really go well with the maple. You don't tend to inlay pictures onto a crown cut back ground but I have seen it done and works well. It usually works best with book matched pieces.

There are a few different ides of getting glue timber. I had though about getting a manufactured veneer that is blond and has been dyed. I would glue the layers together to get a thicker panel to use for the inlay. Or I had though about dying my own. I don't really want to buy a whole stack of veneer since I will only be using a little bit. I had though about using water colors and inks to touch up the inlay sections to make them look like blue.

Well now I know how transparent maple veneer is now.

Not the best pic and even though the offset sections still need to be removed I justed wanted to see what the panels would look like next to one another.

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