Wednesday, 22 April 2015

Woodwork Tips Part 2

Removing Excess Dust:
It is essential that you remove all the excess dust and dirt from your assembled job before you apply a finish to it.

This is to ensure that your finish can be applied evenly and smoothly and if any dust is trapped it will be trapped for good and you will be able to see it.

The best way to remove excess dust is to use a slightly damp cloth and wiping your completed job but make sure it isn’t to damp or your timber could swell.

Glue Spots:
Sometimes you may find that after applying a finish to your completed woodwork job you are left with lighter coloured spots. This is caused from dried glue that has not been removed from the surface.

To locate these spots before you apply a finish you can wipe down your job with a denatured alcohol which will temporarily darken the timber revealing the spots and allowing you to sand them off.

Raising Timber:
This woodwork tip is a technique that is used to remove dents in your wood by raising the surface. This can be done in two main ways which is swelling with water or rising with a damp cloth and iron.

You can apply small amounts of water to the dent which will cause it to swell and rise and this will allow you to sand the surface flat. The other way to raise the timber is by applying a damp cloth to the surface where the dents are.

You then iron the cloth like you would your cloths and this should make the dents rise and allows you to sand them flat. Be careful not to iron the cloth for too long as you can burn the cloth and wood.

Sanding Blocks:
When you are going to sand large or long pieces of timber by hand with sandpaper the best way to do it is with a sanding block. A sanding block is a block of wood or cork that you wrap a small piece of sand paper around.

Sanding blocks make sanding by hand much easier, more comfortable and more consistent because you have the block to support your hand. They are very easy to make or a proper sanding bock can be bought from just about any hardware store.

Sawdust Putty:
Instead of using timber putty you can make your own from sawdust and PVA glue. All you have to do is mix some PVA glue with some sawdust from the timber you are using and then apply it to any holes or cracks in the timber. It also completely matches your timber and you can't see the dry glue.


Tuesday, 21 April 2015

Woodwork Tips


Sanding with the Grain:
This is a woodwork tip that just about anyone with a little bit of woodworking experience should know and it is sanding with the timbers grain. By sanding with the grain and not against it you are able to create a smooth face while not leaving any scratches behind.


Going through the grades:
This next woodwork tip also involves the use of sandpaper and is called going through the grades. This is when you use multiple grades of sandpaper to create an extremely smooth surface.

You start with a small number such as 80 and work your way through each grade until you get to a number such as 200 and this will ensure that your piece of wood is incredibly smooth. These grade numbers are also located on the back of your pieces of sandpaper.

Loosening Sandpaper Fibres:
This woodwork tip is also a tip that many people who regularly hand sand should know and it is loosening up the sandpapers fibres or abrasives.

When you buy sandpaper it is fairly stiff and if you sand with it straight away with a sanding block the sandpaper will get large creases in it and will wear out in half the usage.

A method to prevent this is to find a straight edge such as on a piece of timber or furniture and buy grabbing two corners of the sandpaper and running it along the edge a few times the sandpapers abrasives will loosen and the sandpaper will curl slightly.

This is when you know it is ready for use and it will fit more easily around the sanding block.

Preventing Splintering:
This woodwork tip involves cutting timber either with a hand saw or drop saw although you are most likely to encounter this problem with a drop saw.

There are timbers that are more prone to splintering such as Meranti and cutting it with tools such as a drop saw may cause the edge to splinter.

An easy way to prevent this from happening is by putting masking tape along the area that will be cut and this will help to prevent the wood fibres from splintering.

Another way to prevent splintering is to cut along a marked out line first with a marking knife, this should slice the top fibres creating a straight cut.

Countersunk Holes:
Another woodwork tip for when you are constructing something such as a piece of furniture and you are using screws it is best to make a countersunk hole first to conceal the screw.



A counter sunk hole can be made for any screw but it is best to use countersunk screws. The best way to make the countersunk hole is with a mounted bench drill or pedestal drill but a cordless drill can be used although more precision is required.

It is best to start with the larger whole drilling down just enough to conceal the screw and then using the smaller drill bit as it should easily centre due to the already pre drilled large hole.

After the screw is put in you can cover it with some dowel to fully conceal the screw or make a feature out of the holes.


Source:

Monday, 20 April 2015

Tongue and Groove Joint

A tongue and groove joint is a unique woodwork joint that is attached edge to edge with two or more pieces of timber. It is made with one edge consisting of a slot that runs down the entire length of the timber and a tongue which fits into the slot.


This groove and tongue feature creates a reasonably strong and aesthetically pleasing joint that can be used in areas such as floorboards, lining boards, wood panelling and table tops.

The tongue with a grove feature is easy to attach together because of its simplicity and it allows for a tight fit that has plenty of surface area for adhesives.

These joints can be very difficult to make without the right woodwork machinery. You are more likely to buy timber with this joint already in it, such as lining boards than you are to make it yourself.

Because of the many types of timbers readily available with this particular type of joint it is probably best to buy what you need than to try and make the joint because it is much simpler than attempting to make the joint which requires great tools, machinery and skill.

Also you don’t often require much timber with this joint because it is used as more of a feature in most furniture so there usually isn’t a lot of it used.

Step 1: This joint is really only used for timber boards so the first thing you must do is measure and cut up some timber boards to your required length.

Step 2: This step is not entirely necessary if you have some experience using a router but if not you need to mark the giving and receiving ends on your boards.

Step 3: This step needs to be done with a router bench to create a successful joint and the first thing you do is start with a router bit to cut the groove. After the groove has been cut you now use another router bit to cut the tongue.

Step 4: Check to see if the joint fits tightly and if it does you can now glue and clamp the boards together which will interlock from your tongue and groove joints.

Tip: You can buy lining boards which already have tongue and groove joints cut which makes this option a simpler and easier method for people with time restraints or inexperienced woodworkers.


Sunday, 19 April 2015

Bridle Joint

Bridle joints are very similar to the mortise and tenon joint but the difference is in the size of the mortise and tenon. Because these joints still have a mortise and tenon they are still very strong and fairly attractive.


The difference in the bridle joints mortise and tenon is in the length of the tenon and the depth of the mortise. The tenon on this joint is as long as the depth of the timber it is being inserted into and the mortise is cut the whole depth of the timber.

This allows the two pieces to lock tightly and you can also see the end grain of the tenon unlike on the mortise and tenon joint which makes it a little less attractive.

Because of this woodwork joints increased interlocking area more adhesives can be applied which creates a joint that may be marginally stronger than a regular mortise and tenon joint although it isn't quite as aesthetically pleasing because the end grain of the tenon can be seen.

Step 1: Start by marking out the tenon by drawing a line around the entire piece of wood to create the tenon length. The length of the tenon will be the same depth as the width of your other piece of timber which has the mortise.

You must now mark your tenon width which should be around 1/3rd the thickness of the timber. Check to see if the tenon matches the closest size chisel or mortising drill bit and if it doesn’t modify the lines to match the chisel or mortising drill bit.

Step 2: Now you cut the tenon and there are two methods of doing this the first being with a tenon saw. Put the piece of timber in a vice on a slight angle to create a neat and straight cut and then carefully cut along the lines.

Next put the timber back upright in the vice and mark 5 millimetres in from each end although it can be slightly more with larger tenons.

Now cut straight down where you marked to create small cut outs on both sides of the tenon, the reason you do this is to create a neat and flush joint but it also hides any gaps you may have from your mortises if they are cut slightly to wide.

The second method of cutting tenons is with a band saw and all you have to do is cut along the lines like you do with the saw.

This method is usually better because the band saw has a guide rail making the cuts quicker and more accurate. Remember to cut the tenon shoulders before cutting the rest of your tenon.

Step 3: For this step you need to mark out the mortise and decide where you want to position the joint.

Next you can use your recently cut tenon as a guide for the width of your mortise and you do this by resting it across the timber that will have the mortise and drawing lines along the two edges of the tenon.

After you have the width sorted you must put two more lines in between the ones you have already drawn to create the thickness of your mortise.

The thickness will be the same as the tenons thickness and you can use it again as a template if you need to but remember to measure the space on each side of the mortise to ensure it is centre.

Step 4: Now cut the mortise and once again there are two methods the first involves a mallet and chisel. If you use the first method you need to put some timber in a vice to rest your timber against and then you clamp the two bits of timber together to hold them steady.

Now you get your chisel and hammer it straight into the wood with the mallet. Apply some pressure away from the chisel bevel and repeat this on the other side of the mortise to create a V shape.

Work from the centre to the outside of the mortise and be patient meaning do not remove too much timber at once but also remember to cut the mortise the entire depth of the wood to house the tenon.

The second method of cutting a mortise involves the mortising machine and what you must do is set the width and depth before you use it. Once they are set simply drill into your timber bit by bit to remove the excess wood.

This method is also the faster more accurate one but remember not to drill too much at once and make sure the gap in the drill bit is facing the empty space of the mortise so the excess timber can escape when it is removed.

Step 5: After you have completed the mortise and tenon check to see if they interlock neatly. If your tenon won’t fit you can shave a minimal amount of timber off with the band saw but do it to both sides.

Step 6: Once you are happy with the joint and it fits flush and neat you can now bond it together with clamps and an adhesive.

Always do a dry clamp first to ensure everything fits and always keep checking for squareness while clamping plus remove the excess glue or you will have glue spots which are hard to remove later.

Tip: Remember that on a bridle joint you will be able to see the end of the tenon because your mortise is cut all the way through the timber. The back of the mortise may need some sanding if your tenon is slightly long but remember it is better slightly longer than shorter.


Saturday, 18 April 2015

Mortise and Tenon Joint

The mortise and tenon joint is another one of the strongest and most appealing woodwork joints able to be made because of its flush fitting design.


Like the dovetail joint this woodwork joint can be difficult to properly construct but it is incredibly strong and aesthetically pleasing if constructed well.

This woodwork joint consist of a tongue that is secured into a slot and it is used in areas such as table legs. For structural areas like these the joint must be tight fitting to ensure maximum strength but also to achieve a neat flush look.

There are slightly different versions of this woodwork joint which include double tenons, twin tenons and haunched mortises and tenons.

The haunched version of this joint consist of an extra piece of wood that is half the depth of the mortise and it is mostly used at the end of the timber to prevent twisting.

The double and twin tenons are exactly as they sound being two tenons next to each other which create an even stronger joint. The double tenon is made of two separate tenons while the twin tenon is two tenons which are joined in the middle.

Areas where the mortise and tenon joint or some form of it are most effective and best suited are areas which are required to support a large amount of weight or are structurally important such as the rails and legs of a table or chair.

The tenons should be made to the correct length and thickness depending on how much weight will need to be supported.

For example if the joint is for a large dining table you will need a larger and thicker tenon or even a double or twin tenons to support the extra loads and weights the table will likely endure but also ensure the mortises are tight fitting to create the strongest and most aesthetically pleasing joint possible.

Step 1: The first thing you must do is mark out the mortise or tenons and you can start with the tenons. To mark out the tenon you need to start by drawing a line around the entire piece of wood to create the length of the tenon.

The tenon length is usually about 2/3rds the depth of the piece of timber it is being inserted into. Now you must mark your tenon width and it should be around 1/3rd the thickness of the timber.

Check to see if the tenon matches the closest size chisel or mortising drill bit and if it doesn’t modify the lines to match the chisel or mortising drill bit.

Step 2: You must now cut the tenon and there are two methods of doing this the first is with a tenon saw. Put the piece of timber in a vice on a slight angle to create a neater and straighter cut and then carefully cut along the lines.

Next put the timber back upright in the vice and mark around 5 millimetres in from each end although it can be slightly more with larger tenons.

Now cut straight down where you marked to create small cut outs on both sides of the tenon, the reason you do this is to create a neater and more flush joint but it also hides any gaps you may have from your mortises if they are cut slightly to wide.

The second method of cutting tenons is with a band saw and all you have to do is cut along the lines like you do with the saw.

This method is usually better because the band saw has a guide rail making the cuts quicker and more accurate. Remember to cut the shoulders of your tenons first so that you do not cut to far later on.

Step 3: The next step is marking out the mortise and the first things you need to do is decide where you want to position the joint.

Next you can use your recently cut tenon as a guide for the width of your mortise and you do this by resting it across the timber that will have the mortise and drawing lines along the two edges of the tenon.

After you have the width sorted you must put two more lines in between the ones you have already drawn to create the thickness of your mortise.

The thickness will be the same as the tenons thickness and you can use it again as a template if you need to but remember to measure the space on each side of the mortise to ensure it is centre.

Step 4: Now you must cut the mortise and once again there are two methods and the first involves a mallet and chisel.

If you use the first method you need to put some timber in a vice to rest your timber against and then clamp the two bits of timber together to hold them steady but make sure to put some scrap timber in between the clamp so that it does not mark your timber.

Now get the chisel and hammer it straight into the wood with your mallet. Apply some pressure away from the chisel bevel and repeat this on the other side of the mortise to create a V shape.

Work from the centre to the outside of the mortise and be patient meaning do not remove too much timber at once also remember to stop at a depth that is the same as the length of your mortise.

The second method involves the mortising machine and what you must do is set the width and depth before you use it. Once they are set simply drill into your mortise bit by bit to remove the timber.

This method is also the faster more accurate one but remember not to drill too much at once and make sure the gap in the drill bit is facing the empty space of the mortise so the excess timber can escape when it is removed.

Step 5: After you have completed the mortise and tenon check to see if they interlock neatly. If your tenon won’t fit you can shave a minimal amount of timber off with the band saw but do it to both sides.

If the tenon won’t fully interlock with the mortise you have to remove some timber from the mortise that may be stopping it.

Step 6: Once you are happy with the joint and it fits flush and neat you can now bond it together with clamps and an adhesive.

Always do a dry clamp first to ensure everything fits and always keep checking for squareness while clamping plus remove the excess glue or you will have glue spots which are hard to remove later.

Haunched: If you are making a haunched mortise and tenon all steps are the same except you will leave slightly more timber in the mortise and on the tenon.

The way you cut the tenon is the same only when you make your indents on the sides of the tenon only cut one side. On the other side is where the haunch will be and all you do is cut half way down the tenon to create it.

The mortise will be made at the top of the timber and all you have to do is leave a section that will fit the haunch of your tenon. Instead of cutting this section in the mortise the entire depth of the rest of the mortise leave it half as deep to house the haunched tenon properly.


Friday, 17 April 2015

Dovetail Joint

The dovetail joint is one of the hardest if not the hardest woodwork joint to construct and as its name suggests the joint consists of pins that look like dovetails which interlock into slots.


This pin and slot combination gives the joint great strength and aesthetics but it requires good precision and accuracy during the construction of the joint or it may become loose and it can be unattractive.

The pins are glued into the slots and a nail on each pin can be inserted to help keep the dovetail joint strong and square until the glue dries.

These joints are most commonly found on the front of drawers or on boxes such as a wooden tool box because of its great strength and very attractive look if the joint has been well constructed.

There is usually a three pin setup but more or less pins can be used depending on how much strength and aesthetics you want.

Step 1: The first step is to mark a line at the end of the first piece of timber that is as wide as the thickness of your second piece of timber. Make sure to mark this line around all faces and sides of the timber.

Step 2: The next step is marking out the dovetails now there are a few ways of doing this but the easiest and most accurate would be to use a dovetail gauge.

Other methods use calculations and a sliding bevel to create the dovetails which allow you to create more or less of them but also requires greater accuracy or the joint will not work so a dovetail gauge will probably be more suitable.

Step 3: You must now run across each line with a marking knife to make the cut straight and neat.

Only cut the timber which is being removed or you will see deep scratches on the pins that are not being removed. To help you remember which to mark you can put an X on the pins which are going to be removed.

Step 4: Now you must cut your dovetails and there are a few tools that can be used to do this but the two best are a band saw or dovetail saw. When using a band saw make sure to follow the lines and not cut too deep but remember this method requires much more skill and precision.

If you are using a dovetail saw you put your timber in a vice, it can be tilted at an angle to make the cut easier. Now you just use the saw to cut the straight lines and a cooping saw to cut along the bottom edge.

Step 5: Once the dovetails have been cut out you can use a chisel or Stanley knife to clean up the joints or remove some excess timber.

Step 6: Next you will use your dovetails as a template on your second piece of timber.

Secure your second piece of timber in a vice level to the bench and then line up your first piece of timber on top. You should now be able to use the dovetails as a template and mark lines on your second piece of timber.

Step 7: Once the lines have been marked you must mark lines on the faces of the timber which will be as long as the thickness of the timber. These lines should create pins that interlock with the dovetails so they must be very accurate.

Step 8: Cut out the pins using the same methods as in step 4 and once again remove any excess timber from the joint to ensure a perfect fit.

If the joint was marked out accurately you will have tight or very tight interlocking pins. If they are a bit too tight minimal amounts of timber can be removed. Make sure the joint is flush and square before starting the next step.

Step 9: Now you can bond the joint together with glue but always check to see if it is still square. Some nails can be added in the dovetail pins to keep the joint closed and square while it dries.

Tip: If you are making this joint for a drawer make sure that your larger pins or dovetails are at the front or it will look as good. A piece of timber can be stuck on the front to cover the joints if you wish to cover them up.


Thursday, 16 April 2015

Biscuit Joint

Unlike many of the other joints mentioned biscuit joints are one of the less common woodwork joints. This is mainly because there aren't many places where this type of joint is more useful than another type of joint.


As its name suggests biscuit joints are secured with pieces of timber that are in the shape of a biscuit and these pieces of timber help to prevent movement and add strength.

To construct these joints you need to use a tool called a biscuit joiner which is used to cut the biscuit shaped holes in the wood.

This joint is mainly used to join large timber boards together such as the ones you will find on table tops and it is also aesthetically pleasing if the joint is tight. As mentioned above the biscuit shaped pieces of timber help to stop the large timber boards from moving.

Step 1: First get the two pieces of timber you will be joining together and line them up accurately on a bench and then use a pencil to mark some lines on the timber where you are going to make the joints.

Step 2: After you have marked the position of the cuts secure the timber to a bench or in a vice so that it is steady when you cut into the wood. Adjust your biscuit joiner for the size of the biscuits you are using and cut into the timber where you have marked the lines.

Step 3: Check that your boards join together neatly and flush then bond them together with an adhesive and then clamp the timber up.

Tip: You may need to sand your timber if there is a slight unevenness where you have joined the timber together. The best way to do this is with a portable belt sander.


Wednesday, 15 April 2015

Dowel Joint

Dowel joints are very strong and attractive if they are, like all other joints constructive well. Dowel is also very useful for greatly increasing the strength of weaker woodwork joints such as the butt joint.


This type of joint is secured with an adhesive and a small piece of dowel. Construction also requires nothing more than a drill and some accurate markings.

To achieve perfect markings a special measuring tool can be used to measure the position of the holes for the dowel to be inserted.

The tool is called a dowel centre and they are placed in a predrilled hole to create an accurate mark on the other piece of timber where the next hole will be drilled.

The dowel joint is assembled the same way you would screw a regular joint together only pieces of dowel are glued and inserted into holes instead of screws. By using pieces of dowel over screws the joint becomes much stronger and can be turned into an appealing feature.

Step 1: You need to calculate the size of dowel suitable and then mark where you are going to make the joint.

You can either mark the position of the joint and where to drill the holes with a ruler or you can drill a hole in one piece of timber and use a dowel jig to mark the second piece and this should be a very accurate method if done correctly.

Step 2: The next step is drilling the holes for the dowel but remember to only drill as far as you need to fit your dowel and to use a drill bit the same size as the dowel.

You can drill the holes with a cordless drill or a pedestal drill but the pedestal drill is more accurate so it is usually the best option.

Step 3: Now insert the dowel into one of the pieces of timber and insert the other piece on the other end of the dowel. Bond the joint together with a strong glue and clamps can be used but are not usually needed depending on the size if the timber.

Tip: You can drill a hole all the way through one of the pieces of timber and insert longer dowel but using this method will mean that the dowel will be visible in the back of one of the pieces of timber.


Tuesday, 14 April 2015

Halving Joint


The halving joint is mainly used in framework and is moderately difficult to construct because it consist of two channels that interlock and are bonded together with adhesives and sometimes a nail or screw is added for extra strength.



This type of woodwork joint is very useful for supporting or increasing the strength of two pieces of timber instead of just simply nailing or screwing them together.

It consists of two pieces of timber that have two channels cut half the thickness of both pieces of timber to produce a flush interlocking joint which allows the two pieces of wood to pass through each other.

This joint can be made at both ends of the timber, in the middle or at the end and the middle depending on the design and what it is needed for.


Step 1: First you need two pieces of timber and on the first piece you mark two lines which are going to be spaced out as far as the thickness of your second piece of timber.

Step 2: The next thing you do is repeat step 1 on your second piece of timber so that the lines you mark out are as wide as the first piece of timber. Once all lines are marked out you will notice that the timber should interlock once the joint has been cut.

Step 3: Cut along all of the lines with either a tenon saw or a table saw although a circular saw can be used. Make sure to only cut half the thickness of the timber because if you cut deeper or not deep enough your two pieces of timber will not sit flush.

Step 4: Once you have made your cuts you now remove the excess timber with a hammer and chisel which should leave you with a tight and flush interlocking joint.


Monday, 13 April 2015

Housing Joint


A housing joint can also be called a dado joint and it is fairly simple to make but requires the use of woodwork machinery for an accurate and tight fit. Woodwork tools can be used but with the use of machines the joint has a more quality appearance and tight fit.


A dado joint is made by cutting a channel across the face of a piece of timber about three quarters of its depth, the end of another piece of timber is then inserted and secured into the channel.

This joint is usually used on the back of drawers because it is strong and withstands stress from many directions.

The housing joint is pretty suitable for almost all woodwork projects because of its simplicity and strength. It is also very useful for fibreboard joints such as particle board or MDF because those manufactured boards are not very suitable for a lot of other woodwork joints.

Step 1: The first thing you must do is mark out a channel with lines across the face where you want the housing joint to be. The width of the channel will be the same width as the timber to be inserted into it.

Step 2: Once you have marked out your channel you can now cut along the lines with a saw or you can use a table saw for more accuracy. Only cut the channel about half of the depth of your piece of timber and a router could also be used to do this.

Step 3: Once you have cut the channel you now use a chisel and hammer to clean out the excess timber so that the other piece of timber can be inserted into the joint.

Step 4: clamp up the joint with adhesives and wait until it dries. You can also apply screws and nails to increase strength or to help the joint when applying an adhesive.

Sunday, 12 April 2015

Rebate Joint

The rebate joint is a very similar woodwork joint to the butt joint but the big difference between the two is that one of the ends of the timber has a groove cut out of it to create much better holding strength.


Even with the extra strength the joint is still relatively easy to construct and its appearance is also more appealing compared to a regular butt joint making it a better joint for carpentry or cabinet making.

If more strength is still required you can also add nails, screws and dowel to the joint just like you would on a butt joint but no timber blocks should be needed in the corner because the rebate joint already has a large surface for adhesives to be applied.


Step 1: The first thing you do when making a rebate joint is measure and cut two pieces of timber to the size or sizes you need.

Step 2: Make sure the ends of your timber are flush then get the piece you want you rebate in and mark out the width of the joint the same as the thickness of you second piece of timber.
Now makr another line on you first piece of timber about half its depth and mark around each side of the timber.

Step 3: You should now have connecting lines so make sure they are accurate before cutting.  Use either a tenon saw or a band saw and cut along the lines to make a rebate.

Step 4: You can use a chisel to clean out your rebate if the timber you insert does not sit flat in the joint.

Step 5: If your joint is flush and square secure it together with adhesive.  Nails or screw can be added to increase strength or dowel can also be used but the holes must be accurately drilled before you start step 5.


Source:



Saturday, 11 April 2015

Mitre Joint

The mitre joint is another one of those woodwork joints that is almost as easy to construct and make as a butt joint. Even though it is similar to a butt joint this joint is marginally stronger and has much greater aesthetics.

The reason why this type of joint is stronger and more appealing than a butt joint is because the ends are cut at a 45° angle and then glued together, this creates better surface area for adhesive to be applied while also concealing the end grain giving it a nice flush look.

The best results for these joints are achieved by cutting the angle of the joint with a drop saw instead of a hand saw, this creates very straight and neat edges.

The mitre joint is very common on picture frames because there is no end grain showing and they don't require much holding strength. Sometimes a frame made from this type of joint is used to attach or cover the edges of wood panelling.

Step 1: The first thing you do is draw 45° line where you want your mitre joints to be.  If you have a drop saw or sawing block you should not need to draw the lines.

Step 2: Now either cut along the lines with a hand saw or drop saw but remember if using a drop saw you can usually adjust it to a 45° angle and if using a sawing block it should have a 45°  slot for mitre joints.

Step 3: After the joints have been cut check them to see if they are accurate and then join the joint together with an adhesive and leave it to dry.  If the joint is not reasonably accurate or if ti is cut at the wrong angle the ends will not fit together properly.


Friday, 10 April 2015

Butt Joint


The butt joint is the most basic and simple joint to construct because it is made with only two pieces of timber that are butted together at the ends, this also means that the joint isn't very strong in fact it is the weakest joint that is used in woodwork but it is also the easiest to make.

This joint is held together with glue, nails, screws or dowel but can also be secured with ca combination of methods to greatly increase its strength and aesthetics.
Because the butt joint is so weak and not very aesthetically pleasing it is only used in basic woodwork projects. The strength of this woodwork joint can be greatly increased by adding a rectangular or triangular block of wood in the corner to increase the surface area where adhesives are applied.

Step 1: The butt joint is very simple to make and you start by measuring out the lengths you want you timber to be and then using a try square mark a straight line across the timber where you are going to cut it.

Step 2: Now cut your timber at the line you have marked and repeat steps 1 and 2 on you next piece of timber.
You can either use a hand saw such as a tension saw to cut you timber or you can use a drop saw.  If you are securing the joint together with pieces of dowel drill the holes accurately now before you begin step 4.

Step 3: Secure your first piece of timber in a vice or to the side of a bench with clamps but keep the top flush with the rest of the bench.

Step 4: Apply some glue to the top of the secured timber and then place you next piece of timber directly over your first piece making sure to line up the edges.  Now clamp up the joint or hammer in some nails or add some screws.

Step 5: Now check to see if you're joint is square and leave it to dry.  If you are putting nails or screws in the joint check it is square before you use them.

Step 6: Optional: You can strengthen your butt joint by securing a square or triangle block of wood to the inside of the joint which also helps to prevent movement. 




Soure: 

Thursday, 9 April 2015

Veneer

Veneer is very thin timber that is cut 3 millimetres or less and used to cover either particle board or MDF to give the surface a wood grain appearance.
Strips of this wood are also used to make plywood as it is glued in layers to make it light weight and strong.

This product is widely used in woodwork because it is a useful product that is used to make cheaper furniture like particle board look more like high quality furniture.
More expensive timbers are usually used when making it to increase the quality look and feel of the product it is being applied too. MDF and particle board can also be covered with a plastic laminate but it does not give a quality feel like strips of wood do.

It is fairly easy to bond to manufactured fibreboards, panels and flooring as long as the surface is relatively flat and a good adhesive is used such as PVA glue.
You can also buy this product raw so that a finish of some sort can be applied to increase the strength, durability and appearance of the wood.

If you are attempting to Glue your own veneer to a manufactured board you must be very careful and delicate because it does not take much to damage the sheets.
Also try not to leave any unwanted marks or dirt on the sheets because it may be difficult to remove as you generally can’t sand it because of how thin the sheets are.


Wednesday, 8 April 2015

Plywood

Plywood is another manufactured board that it is made from layers of solid timber veneer that are usually about 3 millimetres thick. Because it is made in layers it is incredibly strong but also light in weight.


The interior layers of these boards are usually made from an inexpensive wood while the outer veneer layers are made from more expensive timber to give the board a nice wood grain appearance.

This type of board is manufactured from layers of veneer that are glued together and compressed under heat, they are then cut into appropriate sizes. With each new layer of veneer added the grain is rotated at 90 degrees each time, this is done to maximise the boards strength and to prevent warping and twisting.

This manufactured board is used as a more affordably option to solid timber or as an alternate to other manufactured boards. You are most likely to see this wood used in places such as school desks, furniture, wood panelling and some flooring although usually only the faces are shown due to the unattractive look of the edges.

Advantages:
  • Very strong
  • Light
  • Resists cracking, bending, warping, and shrinkage
  • Can be made from most timbers to increase aesthetics
  • Good for wood panelling
Disadvantages:
  • Edges of board are unattractive and can't be covered
  • Not suitable for many joints
  • Still may contain natural defects such as knots due to the sheets of veneer

Tuesday, 7 April 2015

Particle Board

Particle board is a manufactured board that is often used in furniture because it can be made cheaply and is more affordable than solid timber but has a similar look.


It is mostly found in furniture that require large pieces such as table tops, desks and TV cabinets, this saves people from having to bond two pieces of timber together to achieve the same size.

This type of manufactured board is made from wood chips which are glued together and then compressed under heat in a large board shape, it is then dried and cut into various sizes to be sold.
These boards can either be bought bare or it can be covered with thin sheets of veneer or a plastic laminate, these two materials give the board a solid timber look and feel while costing marginally less.

Particle board is a good alternate option when buying furniture to a budget because it gives the impression of solid timber and it usually lasts for long periods of time if looked after and taken care of well, like all solid timber.

Advantages:
  • Cost effective
  • It is available in large sizes
  • Veneer or plastic laminate can be applied to make it look more like solid timber
  • It doesn't have natural defects and It doesn't swell
  • Renewable
Disadvantages:
  • Still doesn't quite match the quality of solid timber
  • Can be prone to chip or flake
  • It isn't available in very thick sizes
  • It isn't suitable for many joints


Monday, 6 April 2015

Solid Timber

Solid timber is rapidly becoming scarce and expensive due to logging and the long periods of time it takes for most trees to grow. There are many different timbers on the market that range in price, characteristics and strength.


The two categories that timber can be put into are hardwoods and softwoods and the two can be defined by their differences in the woods microstructure which determines its density and strength.

This timber is an excellent choice for any sort of woodwork but if you want a good quality timber with minimum flaws, be prepared to pay a bit extra due to the reasons above. Cheaper timbers such as pine can be good but don't compare in aesthetics and quality to dearer timbers.

In my opinion solid natural timber is the best type of timber for cabinet making and furniture use because it has the best features and characteristics. Manufactured boards are also good but nothing compares to solid natural timbers.

Advantages:
  • It is the most aesthetically pleasing type of timber
  • There are a vast amount of types for example Tasmanian oak, pine, Jara
  • It is suitable for all woodwork joints
  • Its long lasting
  • There are a range of colours, textures and grains available
  • Takes adhesives and finishes well
Disadvantages:
  • Can be expensive
  • Can be difficult to find the timber you are after
  • Has natural defects such as knots
  • Can warp, shrink, twist or swell 

Sunday, 5 April 2015

MDF - Benefits / Drawbacks

Benefits of MDF

  • Is an excellent substrate for veneers.
  • Some varieties are less expensive than many natural woods
  • Isotropic (its properties are the same in all directions as a result of no grain), so no tendency to split
  • Consistent in strength and size
  • Flexible. Can be used for curved walls or surfaces.
  • Shapes well.
  • Stable dimensions (won't expand or contract like wood)
  • Easy to finish (i.e. paint)

Drawbacks of MDF

  • Denser than plywood or chipboard (the resins are heavy)
  • Low grade MDF may swell and break when saturated with water.
  • May warp or expand if not sealed.
  • Contains urea-formaldehyde, which is a probable carcinogen and may cause allergy, eye and lung irritation when cutting and sanding
  • Dulls blades more quickly than many woods
  • Though it does not have a grain in the plane of the board, it does have one into the board. Screwing into the edge of a board will generally cause it to split in a fashion similar to delaminating.
  • Subject to significant shrinkage in low humidity environments.
  • Trim (i.e. baseboards) comes pre-primed, but this is insufficient for fine finish painting. Painting with latex paints is difficult due to rapid water absorption. Most finishes appear uneven and nail holes tend to pucker.
Urea-formaldehyde: also known as urea-methanal, so named for its common synthesis pathway and overall structure, is a non-transparent thermosetting resin or plastic, made from urea and formaldehyde heated in the presence of a mild base such as ammonia or pyridine. These resins are used in adhesives, finishes, MDF, and molded objects.


Urea-Formaldehyde is everywhere and used in many manufacturing processes due to its useful properties. Examples include decorative laminates, textiles, paper, foundry sand molds, wrinkle resistant fabrics, cotton blends, rayon, corduroy, etc. It is also used to glue wood together. Urea formaldehyde was commonly used when producing electrical appliances casing (e.g. desk lamps).

The product is widely chosen as an adhesive resin due to its high reactivity, good performance, and low price. Urea-formaldehyde resin is a chemical combination of urea and formaldehyde. Amino resins are considered a class of thermosetting resins of which urea-formaldehyde resins make up 80% produced globally. Examples of amino resins include automobile tires in order to improve the bonding of rubber to tire cord, paper for improving tear strength, molding electrical devices, molding jar caps, etc.


Saturday, 4 April 2015

MDF - What is it?


Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibres, often in a defibrator, combining it with wax and a resin binder, and forming panels by applying high temperature and pressure. MDF is generally denser than plywood. It is made up of separated fibres, but can be used as a building material similar in application to plywood. It is stronger and much denser than particle board.


The name derives from the distinction in densities of fibreboard. Large-scale production of MDF began in the 1980s, in both North America and Europe.

In Australia and New Zealand, the main species of tree used for MDF is plantation-grown radiata pine; but a variety of other products have also been used, including other woods, waste paper and fibres.

The trees are debarked after being cut. The bark can be sold for use in landscaping, or burned in on-site furnaces. The debarked logs are sent to the MDF plant, where they go through the chipping process. A typical disk chipper contains 4-16 blades. Any resulting chips that are too large may be re-chipped; undersized chips may be used as fuel. The chips are then washed and checked for defects.

The chips are then compacted using a screw feeder, are heated for 30-120 seconds to soften the wood, and then fed into a defibrator. The defibrator maintains a high pressure and temperature while grinding the wood chips into a pulp.

From the defibrator, the pulp enters a blowline, where it is joined with wax and resin (often UF). The wax improves moisture resistance and the resin initially helps reduce clumping, but ultimately is the primary binding agent. The material dries quickly when it enters an expansion chamber and expands into a fine, fluffy and lightweight fibre that is stored until needed at the forming line.

Dry fibre gets sucked into the top of a pendistor, which evenly distributes fibre into a uniform mat below it, usually of 230-610 mm thickness. The mat is pre-compressed and either sent straight to a continuous hot press or cut into large sheets for a multi-opening hot press. The hot press activates the bonding resin and sets the strength and density profile.
After pressing, MDF is cooled in a star dryer, trimmed and sanded. In certain applications, boards are also laminated for extra strength.

The Environmental Impact of MDF has greatly improved over the years. Today, many MDF boards are made from a variety of materials. These include other woods, scrap, recycled paper, bamboo, carbon fibres and polymers, forest thinnings and sawmill off-cuts.

As manufacturers are being pressured to come up with greener products, they have started testing and using non-toxic binders. New raw materials are being introduced. Straw and bamboo are becoming popular fibres because they are a fast-growing renewable resource.


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