Thursday, February 26, 2009

Update Feb 2009

Ok folks.. been a little while to update - doesn't mean we haven't been progressing. Let's just say that it has been 1 step forward, 2 steps backwards this month. Here's the drill....

Retracts ordered and arrived. Finally determined that they won't fit. Remodelled retract slide trays to work with the CJM retract set but won't be using the struts - using standard GreatPlanes/Robart bolt-on steel axles instead. Slide trays fitted and fuse modified to suit. Threw out servo mounting tray in the process - useless... replaced with mounting rails. Slide trays now off to be sheeted in carbon fibre and epoxy for additional strength. Wheels ordered (and on back order) - looked at going to another manufacture but didn't want to take the extra weight hit. Front retracts mounted. Had to do some minor mods to get all that to fit (slightly lengthed the space between the former pieces. Retract mounted on rails epoxied into place.

Things I've learnt this month:
1. Don't set out off these plans especially the keels that need to be bent - allow longer length than shown on sections. If something has to fit into the space later - use that to set out against - again - DON'T use the plans(refer front nosewheel bay and retract slide boards).
2. The plans are TOTALLY useless when it comes to the truss framing and the retract slide boards - they do not work.
3. There are two different sets of plans out there for the 87" version of this plane - one set identifies Goldberg retracts (yet noone at Goldberg knows what retracts were to be used on this model) and the more modern version (dated the same) using Robart retracts however this would require modification of the truss frame which wasn't incorporated into that drawing set - how do I know this? I now own both sets of drawings and have done the comparison. The mod I've done to fit the CJM air-retracts *should* work for the Robarts as well.
4. The plans do not identify ANY means of opening the front half of the nosewheel door. Plans are underway to resolve this matter - another servo is likely to be involved.
5. A good number of the pieces from the kit cutters are incorrect and are having to be cut from scratch.

Status - About one month behind schedule although catching up fast. Truss done, retracts all in, air system roughed in (and working), receiver programmed (initially), radio programmed (initially), receiver mounting rails installed. Full steam ahead to get the fuselage finished.

Photos to follow shortly.