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From Peter Mitchell - 15th Jan 2005

My first impression of the model when I received it was that apart from it being very nicely made, the wing seemed to be a bit on the flimsy side. But then I am used to the Taboo!

The recent thread on RCGroups about the dihedral join failing on launch is worrying, but as I am not in the superlaunch league I hope I will not experience the problem.

Anyway I decided to try to make the plane as light as I could. The fittings supplied with the Blaster are OK, but not if you want to save weight. The pushrods, clevis and horns weigh 30grm. So I replaced them with Martins steelwire/Teflon tube pushrods and my own horns and fittings which saved 20grm!

The tailplane is of the AMT variety and is mounted on a very nice V mount unit. It says on the website instructions that this unit weighs 1gm. My one weighed 3grm. A bit of work to remove the metal bolt which is cyanoed into the mount, drill and tap a new thread, replace the metal bits with a small nylon bolt and some careful rubbing down reduced the weight to 1.8grm.

The servos for elev/rud. are Futaba S3106 which are fairly powerful and light and a good overall height for this fus. To make installation a bit neater, I clipped the mounting lugs off each servo, re-routed the wiring to side exit and heatshrunk the two servos together end to end. This 'unit' was then epoxy/micro ballooned into the fus with 30min epoxy.

To keep the weight down I decided to use the new S100 Ripmax servos. They weigh about 5grm and are rated at 1.1kg torque. It's a big flapperon on the Blaster, and other micro micros I have used in the past have all failed in similar use. However I thought it worth a try. I wanted to make the servos removable, just in case. I decided to try making the mount as per Tabboo i.e. a pocket cut out of foam. I printed a rib profile with my Profili program and used this to cut a pair of foam 'ribs' which were 10mm wider than the servo all-round. The 'ribs' were then cut into 4 smaller sections that could easily be passed through the servo sized hole I cut in the wing. A 'dob' of epoxy was spread in the wing and the 4 pieces moved into position. Once the glue was hard I routed out the servo hole. The servo is secured in place with L/W filler and a strip of tape. Total weight gain fitting both servos is 1grm.

The throwing peg is replaced with my own flat peg. This required an extra bit of work and some reinforcement.

Total finished flying weight is 324grm balanced as per instructions, the weight out of the box was 216grm so despite my best efforts the plane has gained 108 grms although this includes all the flight equipment.

So far I have had only a few launches. It flies very nicely, launches well and should be good once I have trimmed it out to suit me.

One or two points of interest may help other Blaster builders. The guidance/instructions to set the tailplane angle is a bit 'agricultural You are directed to set the tailplane by sighting the model from the rear and aligning the t/e of the tailplane with the top of the wing. The result I achieved was too much down trim and a scary first discus launch. Far better if you have a measurement to work on. I found that a setting measured between the trailing edge of the tailplane and the top of the fus. boom of 21mm should be about right. As the wing has no fixed centre section, the only fixed point of reference is the tip. I made a lower section template out of card and with my Profili and found that when the tips were in line with the flapperon, the section at the root of the wing was slightly reflexed. A small twist in the flapperon probably but it will have an effect on performance. After a few launches I have moved the CG on my model back to 80mm from the leading edge. I can't wait for some good calm weather to trim the model out properly.

Peter Mitchell