This is a less-safe alternative to spending approximately £250 on 51 47 7 380 665 and supporting parts, especially since they are NoS (No Stock) parts that need to be specially ordered from factory.
It's not an exact replica of 51 47 7 380 665 -- the original is 2kg lighter. It's also slightly stiffer as its made out of epoxy resin/fibreglass composite. Having said that, the 18mm MDF provides reasonable stiffness and moisture resistance once sealed properly.
The two parts hinge only using the carpet. Consider installing three piano hinges for more stiffness and loading capacity. If you add them, subtract appropriately from the length of the base element.
The original part is anchored to the car for better crash resilience. You must understand that neither this project part nor the original part pass crash test regulations without the supporting mounts. Do not be tempted to plop the -665 alone and call it a day. The proper, smart BMW engineers have put a lot of thought into this. Do not ignore it!
This project part has not been crash-tested. You must assume and expect it to fail in any and all crash scenarios in the most spectacular and catastrophic way imaginable. I am not an engineer. This is not engineering advice.
It would be sensible to only use it when you are transporting large items requiring a flat floor -- in which case the safety in a crash is already compromised by a large, unsecured mass inside the cabin, where the squishy bits are.
For completeness, to do a fully compliant installation, you would need:
- Floor carpet, luggage compartment (1) 51 47 7 380 665 €181.50
- Trim panel, cross member, trunk (1) 51 47 7 380 671 €48.00
- Expanding rivet (4) 07 14 7 401 727 €1.03
- Mount for trunk floor panel (1) 51 47 7 380 666 €60.91
- Countersunk screw M6X16 (4) 07 11 9 907 139 €1.47
For total of €291.91 or ~£250 ex VAT. Your friendly local dealership will probably charge twice that amount for fitting (merely an opinion; also this list may not be exhaustive, I am not a certified BMW/MINI parts specialist) and add VAT to the prices; so below is the cheapskate alternative.
- Two pieces of 18mm 610mm x 1220mm MDF, £17
- Two pieces of 1m 11.5mm x 19.5mm aluminium bar, £9
- 1400mm x 1000mm automotive carpet, £6
- 500ml can of automotive trim adhesive, £7
- small piece of 9mm MDF to cut the 9.5cm x 2.5cm locators by hand, £free - ask at a local DIY shop for an offcut.
- 250ml can of Rustins Quick Drying MDF Clear Sealer £3.50
- 6x5/8" twin-thread wood screws, box of 200 - £1.66
- Tools (small drill, 2mm, 3mm drill bits, countersink (or a 10mm metal bit), brush, Pozidriv screwdriver)
- CNC the 18mm base and flap (your friendly local CNC shop should be able to make sense of one of the above files) (£48) or transfer it from paper if you have a router and a steady hand.
- Seal the MDF, two coats on edges, one generous coat on faces. Let dry well.
- Fit, mark and drill with 3mm and counter-sink both angles of the aluminium bars every 12cm, sides offset by 6cm to each other. Start with centre hole on the edge (longer side of the bar goes on the edge, short on the face of the boards at the hinge).
- Drill pilot holes with the 2mm bit on the notch edges of the boards. Shorter edge of the bar facing down. Long edges facing eachother between the panels.
- Wrap the short edge of the fabric around the inner (notch) edge of the base element (underside up). Secure it with the centre screw and work your way symmetrically from the centre with the remaining ones.
- Lay the base element underside up with bar away from you. Fold the fabric with the wrong way out in a loose roll leaving approx 50cm is hanging off of the bar.
- Spray adhesive on underside side of base. Follow instructions on the can.
- Wrap fabric from underneath the base from the aluminium bar to the edge, smooth out as instructed on the adhesive can, let dry and cure. Turn over, top side up, bar facing you.
- Spray adhesive on edge and top side of the base element. Attach to base top. Let dry.
- Put the notch (meeting) edges of MDF together (but don't screw the bar on the flap yet), allign. Wrap fabric across the flap, over the curved edge and back towards the notch on the flap element underside, don't stretch that part when you glue it on.
From the curved edge, you will need to stretch the fabric as you cover the bottom side as much as it will stretch to go around the curved part. The fabric needs quite a lot of stretch for a good finish but is made to do it. Start at the handle area and work towards the sides in 2-3 sections stretching the fabric towards you as much as you can. It looks impossible at first but it works.
- Once you have stretched and glued the bottom of the flap the remaining short edge to the underside of the flap element at the notch edge goes under the second aluminium bar.
- Let the adhesive set while the bars are facing up.
- Trim the excess fabric. Think twice, cut once. (Failure to follow this advice will result in excessive cursing and a full re-trim). Fold the edges from the top side neatly using the adhesive. Watch out with the amount, it can seep through if there's too much.
- Place the locator tabs in the slots near the rear seats and the floor on top. Mark the location from underneath using chalk/soap/velcro.
- Attach the locator tabs in the marked positions using longer wood screws, don't forget to drill ϕ3 pilot holes and counter-sink the heads so the MDF does not crack.
- Cover the locator tabs with fabric using the spray adhesive.
Total cost of materials and services ~£100.
DISCLAIMER: Prices correct at the time of writing. I am not affiliated with the above-linked entities.
Neither me or my employer endorses the above companies, vendors, or products. I have NOT received any
special pricing or discounts in exchange for mentioning them here. Those links are provided for
reference and your convenience. I do not guarantee accuracy or fitness for a particular purpose of the
linked materials or services. Your experience may vary. This information is provided as-is and without
warranty of any kind. Follow at own risk. This is not engineering advice.
Opinions expressed on this page are mine and not my employer's.
WARNING: MDF is pretty nasty when inhaled in powder form. Wear face and eye protection when working it
especially when cutting/sanding.
Keywords: F60 MINI Countryman flat boot trunk floor DIY