I will keep this short and sweet since most of you (in the reprap community) have probably already seen posts like this time and time again. So basically here is a few snapshots of my build progress
Everything went together fairly easily, there were a few minor errors in the assembly instructions which I corrected. The only trouble I had was with Adrian’s geared extruder driver. The base has countersunk holes to fit the heads of M4 bolts, however they were not big enough and reaming them out to 7mm I almost drilled right through. I also felt that the extruder design in general was a bit “bitty” and so I am re-designing the thing from scratch. Here is a sneak peek
The following view shows the lower half of my redesign of the axle mount, it fully encapsulates the bearing rather than having them floating free. (The image shows two separate parts which would be bolted together)
I am intending to also use my internal teeth gear concept with this design
I also designed a hobbed m4 insert
The hobbed insert will soon be available to buy courtesy of raysu in his ebay shop. Price is currently TBC, but he offers similar items at around $8.50
Giles Bathgate 
I am interested in seeing just how well your internal teeth gearing works out for you. I like the idea a lot.
Could you make the extruder base to mate with the makergear style groove so that one wouldn’t have to glue the insulator into it. Been meaning to do that myself, but haven’t gotten around it yet.
Sure I will give it a go, could you post a link of the ‘makergear style groove’ to clarify what you mean?
Thingiverse has some groove mounts for makerbot extruders: http://www.thingiverse.com/thing:3744
I’ve hacked a piece of wood to act as a groove mount, and I’ve had to change between insulators.
I’ve bought this http://www.reprapstores.com/catalog/extruder-parts/machined-parts/tb-hybrid1g and the makergear version.
It would be nice if would accept BFB-style hotends also. Arcol is making a nice and affordable hotend in that style: http://blog.arcol.hu/?p=1689
(the x-carriage needs adapting though: http://www.thingiverse.com/thing:3017)
Some one has made an adapter, but it looks a bit fiddly and is an stl: http://www.thingiverse.com/thing:2088
Ah, now that I know what you mean I don’t think I will be making any changes to the design specifically for the grooved insulator. The hot end will be supported by my really cheap and easy to make Rounded Support Block and I will be publishing some ways in which some existing insulator designs such as the grooved one can be fitted.
As for the BFB style hotend, I am not interested in trying to fit that to the design at this stage. Of course that dosen’t mean that someone else is not free to do so later.