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Step 1 - Determine which style you want
Immix stair parts may be fitted in one of two ways.
2. Over the Post - where the handrail extends over the top of the newel post.
Step 2 – Over-the-post
These instructions are for the over the post installation of the Immix system only.
Step 3 - Measuring stair pitch
Measure the pitch of your staircase.
You may use the printable protractor to do this.
There are other methods of measuring your stair pitch, including measuring tools and also apps for your phone/tablet that can be used. Whichever method you choose to adopt, make sure that your reading is accurate otherwise your calculations will be out.
Step 4 - Measure newel distance
Using a good tape measure, measure the distance between the newel post inside faces (ND). Enter this, along with the stair pitch, into the Wonkee Donkee calculator. This will give you the spacing and
quantity of panels you will need.
Note: Be aware of errors that can creep in when measuring the newel distance with a tape measure, particularly when measuring right into an angled corner. See next step.
Step 5 - Using the tape measure
Being a tight angled corner means that the tape measure will not get right into the corner, resulting in an error that can easily be as much as 15mm (the height of the tab), and incorrectly spaced panels.
Make sure that you measure from the newel base and that the tape measure is flush with the top of the baserail, otherwise the tab on the end of the tape measure will lift the tape off the baserail and cause errors in your marking out.
Step 6 - Mark bottom and intermediate newels
Place an offcut piece of baserail onto the string and make a pencil mark where it touches the newel face.
Continue this line along the side face of the newel at the same angle as the stairs and baserail (shown).
Make a mark at the centre of this line (effectively the centre of the newel post).
Measure up 175mm from this point and, using a square, mark a line showing where to cut the newel. Continue this line all the way around the newel post using the square.
Repeat for all intermediate newels on stairs if present.
Step 7 - Mark top newels
Mark the top newel post in the same way, but this time measure up only 125mm from where your marks intersect.
Step 8 - Trim newels to height
Trim all newel posts to your marks using a fine-toothed handsaw. Ensure that the saw is kept level and straight at all times, taking care when “breaking through” to avoid splintering the timber.
Step 9 - Intermediate newel post
If the distance between newels is greater than 2400mm, then you will need to fit an intermediate newel base. These are available in lengths of 510mm, 700mm, and 915mm and are pre-drilled to accept the Immix newel post. They will, however, require fitting to your stairs which will entail carefully slotting the base to fit over the string, and removing material so that it fits the profile of the step.
Ensure that the finished height of the newel is 175mm above the intersection of the newel post centreline and the finished height of the baserail as shown below.
Step 10 - Measure existing newel
Measure the width of your existing newel post - this should be no less than 90mm x 90mm square and installed central to the riser and string. If the section size of the newel base is less than this, it will have to be built up by cladding each side equally to get to the required size. Use adhesive and pins to fix in place, cladding the newel so that it ends flush with the top of the newel base.
Step 11 - Mark and drill newel bases
If using existing bases, locate and mark the vertical centreline of the newel face (stand on the step, turn towards the newel - it’s the face facing you). Measure down 125mm and mark the centre point for the 35mm diameter hole. Drill hole to a depth of 62mm. (A)
Locate and mark the centre on top of the base by drawing a diagonal line across each corner. Drill a 50.8mm diameter hole to a depth of 35mm. Follow with a 13mm drill bit to drill a hole to a depth where it intersects with the 35mm diameter hole. (B)
Step 12 - Install baserail
Lay the baserail on top of the stair nosing and offer up to the side of the newel bases.
Mark a vertical line following the inside face edge of each newel base.
Remove and carefully and cut to length.
Step 13 - Drill and fix baserail
Position the baserail between the newel bases, ensuring the rail is central to bases. Drill pilot holes through the baserail into the string.
Ensure that all debris is cleared from within the rail groove before securing the baserail to the string.
Reposition the baserail and fix to the string using No.6 x63mm
screws. Make sure that all the screw heads are below the surface
and do not project into the groove.
Step 14 - Install the top newels
Position the newel base connector on top of the newel base and mark the position of the screw holes. Pilot drill using a 3mm drill bit and fix the connector to the base using the supplied No.8 screws.
If the newel base is larger than 90mm x 90mm, ensure that the connector is lined up correctly using the previously marked diagonal lines as guides.
Step 15 - Secure the top newel post
Insert the circular locking nut into the 35mm diameter hole ensuring the arrow is facing outward and up. Insert the threaded bar on the bottom of the newel post into the newel base locating in the locking nut. Tighten with an allen key until the newel post starts to be drawn down. Ensure that the newel sits within the newel base connector.
Tighten until fully down.
Step 16 - Intermediate and bottom newels
Cut the Intermediate and Bottom newel posts to length. Choose form the list below depending on the pitch of your stairs. If the pitch falls between two listed pitches, adjust the newel length accordingly.
(see table below)
Step 17 - Install rake connector
Insert and fix the intermediate and bottom newel posts into the newel base following the same instructions for the top newel.
Place the Intermediate rake connector onto the top of the intermediate newel and mark the position of the screw holes. Repeat for bottom newel.
Step 18 - Secure connector to newels
Using a 3mm bit, pilot drill the fixing holes.
Secure the intermediate rake connectors to the intermediate and bottom newel post using the supplied screws then set the arm on the
connectors to the same pitch as the stairs and tighten.
Step 19 - Install handrails - mark and cut
Place a length of handrail on the stair nosing up against the newel bases and mark the position of the inside face of the top newel base and cut the top end of the handrail to the angle of the newel.
For the bottom end of the handrail where the handrail projects past the bottom newel base, measure 90mm from the outside face of the newel base and cut off square.
Step 20 - Secure connectors
Offer the top rake connector to the top end of the handrail ensuring the top of the connector is as close to the top of the handrail as possible. Pilot drill through the screw holes using a 3mm drill bit and secure with the screws provided.
Install the rail end connector to the bottom end of the handrail which you have just cut square. Mark the hole position located within the groove and pilot drill. Offer the rail end cap over the handrail and secure with the No 8 screws provided.
Step 21 - Install handrails - mark and cut
Cut 2 x battens at 795mm high x 50mm wide x 8mm deep cut at the stair pitch and locate in the baserail groove.
Offer the handrail between newels and over the intermediate rake connector ensuring that the bottom of the handrail groove is sitting on the top edge of the battens.
Step 22 - Mark position of top connector
Using the location grooves on the sides of the connector, mark the location of the bolt holes for top rake connector on the newel posts.
Step 23 - Install handrails - marking out
Using a square, mark a line around to the opposite face of the top newel followed by a vertical mark to show the centre of the newel.
Step 24 - Secure connectors
Drill a counter bore hole using a 16mm diameter spade bit to a depth of 20mm, followed by a 10mm diameter clearance hole right through the newel.
Step 25 - Install handrails - secure to newel
Offer the handrail between newels and onto the intermediate connector. Secure the rake connector to the top newel using the bolt and washers supplied.
Step 26 - Secure connectors
Secure the handrail to the intermediate and bottom connector by drilling 3mm diameter pilot holes through the intermediate fixing arms located in the rail groove and secure using the No 8 screws
Step 27 - Measure for glass panels
Measure 60mm from the newel bases along the top face of the baserail and mark. This will locate the position of the side edge of the first and last glass panels.
Step 28 - Cut fillets
Cut fillets for the bottom of the stairs for the handrail and base rail.
Ensure that fillets are cut to the
angle of the stairs. Drill a 4mm hole down through the centre of the fillet parallel to the cut sides and then
countersink so that the head of the screw sits below the top of the fillet.
Pilot drill and fit the
bottom fillet using
Step 29 - Check positioning
Check that the top fillet is the correct length before fixing it into place. To do this, place the bottom edge of one of the glass panels into the base rail groove and pivot to fit into the groove of the handrail. Make sure that the glass butts up against both fillets. Check that the gap between the glass edge and newel post is the same near the handrail as the gap near the baserail.
Once the glass panel is parallel to the newel post, remove and place safely to one side. Fix the top fillet into the
handrail groove by pilot drilling with a 2.5mm drill bit and then securing using No.6 x63mm screw.
Step 30 - How many panels?
To work out how many panels and the size of fillets required,
measure the distance between the two marks on the baserail.
Divide this measurement by 350 and round the figure down to the next whole number. The result is the number of panels required.
Multiply this number by the panel dimension according to the pitch of your stairs (See table).
Subtract this figure from the original measurement.
Divide by number of panels (less 1) to get the fillet size
Measurement between marks = 1820mm
1820mm divided by 350 = 5.20, rounded down to 5
Pitch of stairs is 42 degrees so panel dimension is 269mm x 5 = 1345mm
Original measurement 1820mm minus 1345mm = 475mm
475mm divided by 4 (number of panels less 1) = 118.75mm (length of fillet)
Please note - maximum length of fillet must not exceed 129mm. If maximum length is exceeded add another panel by rounding up (after dividing by 350) and re-calculate.
Step 31 - Install glass panels - sealant
Cut all fillets to length and drill a clearance hole parallel to the cut sides through the centre using a 4mm bit and
countersink so the screw heads are below top of fillet.
Cut all decorative plastic strips (supplied with rails) to suit using a junior hacksaw.
Apply a bead of clear silicone to both the handrail and the baserail grooves ensuring that you also put a bead on the side wall of the handrail groove.
Step 32 - Secure connectors
Insert the glass panel into the top and bottom grooves and up against the previously installed fillets. Install another set of top and bottom fillets, pilot drill and secure. Repeat.
Depending on how many panels are used and the gaps between them, you may have to insert the last two or three panels into the groove first before installing fillets.
If this is the case, wrap some cardboard around the side edge of the panels and insert, carefully allowing them to butt up to each other.
Once all panels are in, separate the panels by installing the fillets between them and securing
the fillets in place as previous.
Push the decorative plastic strips P/PSGM supplied with the rails into the grooves
to hide the timber fillets. They should be a good fit, but because of manufacturing
tolerances of the glass and the grooves, the glass or plastic trims may seem a little loose.
If this is the case, secure with clear silicone.
Glue the Newel Cap to the top of newel post and the Rail End Cap to the end of the handrail and insert all bolthole cover caps by tapping them in.
Silicone all of the square timber cover caps P/IMTCCWO (white oak) into the newel bases.
Step 33 - Check
Check that all fittings and glass panels are secure and correctly placed.
Step 34 - After care
Wipe down with a damp cloth and enjoy!