"a twisty dodecahedron"
My first megaminx was from puzl.co.uk as part of a set with a puzl competition speedcube which I got around October 208. This is what many know as a "PVC minx" and it is stickered with decent quality lexan tiles with good colour differentiation -- important when there are 12 sides to distinguish between!
This was during the run up to the UK Open speedcubing event so I was concentrating on the 3x3x3 and I didn't spend much time with it. I could solve everything apart from the last layer which I just couldn't figure out without some help. When the UK Open had passed I started playing with it more and I learned a couple of algorithms to finish the last layer.
Using a fixed sequence of colours helps me immensely - otherwise I spend too much time looking for better opportunities! I have a few Megaminxes and I have fixed colour sequences for each one. I don't have the relative positions of the colours memorised per-say, but since I perform the same order I seem to learn them over time anyway.
I always start with the white side and I solve it on top - well, sort of on top - it seems to vary! I first make the white "star" - analogous the the cross in Fridrich. Then I place all the white corners along with their edges, so it's 5x F2L pairs using the same "intuitive F2L" rather than algorithms.
Next I favour one of the sides (I have my favourite colours for each minx! Yellowish-orange on the MF8) adjacent to white that now has two F2L pairs. I add the remaining 2 edges of that colour and then the 3 F2L corner-edge pairs of that colour. White now goes to the bottom
I then take my next favoured colour for one of the sides that now has 3 F2l pairs in place (purple on the MF8). This one needs just 2 F2L pairs. Same for orange, and we're down to two faces that need to be completed
...to be continued...
The last layer edges are oriented (OLL with last layer on top) with FURU'R'F' and FRUR'U'F' (todo show cases).
Next I permute these 5 edges to put them in their correct places with Sune and Anti-Sune algorithms (image from Lance Taylor's YouTube video at http://www.youtube.com/watch?v=oijt5WC6_FY ): -
Next I orient the corners of the last layer with a "zipper" -- Last Layer is on top with corner to twist at UFR (upper-front-right) - however I like to think of the corner facing me. This funky open-and-close algorithm L'RL'R' reminds me of a zipper opening and closing! I learned this from Erik's Megaminx page (todo: link)
So with corner facing me (or UFR to be accurate) I do L'RL'R' a couple of times until the corner is correctly oriented. Then adjust U for next unoriented corner and repeat. The nature of the puzzle ensures that the messed up pieces of the L and R faces end up fixed again after the right number of cycles. Just to play with this algorithm, starting with a solved minx perform it 6 times to cycle back to the solved state.
Final step is to permute the corners with a commutator. I learned this from (todo)
I was delighted with the build quality of the DX minx (SKU 16334) for $7.30 (USD) - horrible colour scheme and after the raised tiles of the mf8 there's hardly any grip! I had the great idea of restickering with a good set from cubesmith and some clear rubber cushions on the corner pieces...
The clear "nubs" take on the colour of the stickers underneath. I got these ones from Wilkinsons, a popular hardware store in the UK.
Only the corners need the extra grip.
...to be completed...