Sunday 24 June 2012

Week 46 - Spar tunnel reinforce part 2

Hours to date: 418.75


Didn't get anything done during the week as I was very busy at work - late nights every evening.


Managed to get the Starboard outer and inner spar tunnel reinforcing done this weekend though.


Also after speaking to Pete he has recommended I put a strip of carbon over the wooden seat belt block. He said that he was very welcome of that extra strength during his crash with the first Twister.


Accident report here if you are interested in what happened.


http://www.aaib.gov.uk/publications/bulletins/november_2005/silence_twister__g_twst.cfm


Hopefully I can get the rest of the underside of the spar tunnel reinforced this week. Next weekend is busy for me as I am going to the Goodwood Festival of Speed - nice to have a break now and then.


Starboard outer and more carbon on seat belt block

Inside of Starboard wing root to Spar tunnel



Sunday 17 June 2012

Is it just me?

Or are these two getting closer these days?



Week 45 - Spar tunnel reinforcing

Hours to date: 412.25


Work this week was on the wing spar tunnel, which needs to be connected properly to the safety cell and fuselage.


This is done anywhere the two touch. I have done the inside and one wing root so far.


Nothing much to say about this job - pretty straight forward really. Just think about all the curves you have to go round and use several smaller pieces of carbon rather than going for one long strip each side - which would be a nightmare to work with.


The main new thing here was that I was using several layers of Carbon at once. And the weave must be offset by 45 degrees between each piece to give strength in every direction of load. 2 layers on the cell and 3 layers needed on the wing root. Each layer is 10mm less width so there is a smooth transition rather than a huge step.


Next job will be to flip over the fuse and do the other wing root and then the rest of the joins on the inside of the wing roots and the cell.


Spar tunnel to cell reinforcement

Spar tunnel at wing root - before starting the job

Job done.

Monday 11 June 2012

Week 44 - Safety Cell mod - Part 4 and UC work

Hours to date 402.75

Finally finished the safety cell mod - well all the Kevlar is done - still got to pretty it up with some filler and paint - but that can wait till I am ready to paint the interior of the safety cell. What colour? Grey seems to be the popular choice. I'll most likely go for that.

As you can see from the below photo I can just touch the end of the cell with a pointed toe - so that should be well clear as the rudder control on full lock will not be that extreme a movement.

Next up I decided to tackle some of the main gear reinforcement - most of this will not apply to anyone building a retractable version.

The gear mounts have a layer of carbon on the inside and 4 metres of carbon roving wrapped around each 'knee'.

I hadn't worked with roving before but this job seemed to go okay. I cut each 4 metre piece into 1 m sections to make life easier. As you can see the 'knees' needed roughing up before applying the roving.

You can easily fill in any gaps in the windings with some spare carbon strips left over from other jobs (I knew these would come in handy!). Several can be wound together to form a thicker strip and easily bonded into place.

Next job may well be reinforcing the cell to wing spar box - which must be done inside and out with carbon.

Pedal position test

Leg room just right now
Cell mod complete - still got to tidy up and paint

Gear leg position check

Gear mount pre-reinforcement


Post - with carbon

'Knees' of gear legs that need reinforcing

Gel coat taken off and roughed up

Roving in place