Micromeister
7th February 2011, 05:14 PM
Aligning fins for micro competition models is where these particular fin alignment jigs came into being a couple years back, Never really thought too much about it until I saw another thread here on TRF recently. I'm sure I must have seen something similar somewhere in the past as I assumed this type fin jig was a common use item for most serious competition flyers and have had fine success using it on sport flying micros as well.
The Prototype was made from 1/4" transparent acrylic plastic I had laying around the rocket dungon with a couple 2" x 2" x 1/8" aluminum angle legs and some 4-40" hardware. In the beginning it had a 1/8" aluminum retainer strap squeeze bar which was quickly replaced with a 1/4" bar when I noticed i'd bent up the thinner strip during the first couple uses on micro PD models.
These Jigs works well with models from T2 (.246") diameter tubing to BT-55 (1.325"). I've never really tried anything larger as I'd think the body length and internal mandel weight might be an issue?
I've used the prototype jig on micro T2+ to BT-20 for compeitition style models with standard craft body tubes and double taper paper transitions models with great success to get no spin models with a simple internal mandel to keep the paper models from deforming in the straps.
My recently finished all aluminum model is 2 inches longer with an 8" v-groved holding section and 2-1/2" fin deck. The longer length helps making longer body models a bit easier to control.
While spring clips can be used to hold fins in place on the fin deck i've found them totally unnecessary with all but the largest overhanging fins.
If you have any type of saw that can be set up to cut a 45° angle, making these fixtures is a fairly simple chore. Wood would not be my choice as warping and moisture content unevenness would be a constant concern. Phenolic barrier board might be OK for larger models or fin jig construction?
While this jig doesn't work for models with far forward fins or long fin strakes it does well with most multi fin set models by working from the rear fins forward, sliding the body aft as you go.
Leather straps were chosen over other type fastings so the body could be held firmly as yet still allow it to be turned without releasing the pressure to align the next fin. The Deer hide I used could easily be replaced with any soft leather one might have laying around.
Below are a couple pics of the prototype & all Alum. micro Fin Alignment jig. I've had fun with this tool, I believe it would be a useful addition to the most any micro building bench.
The Prototype was made from 1/4" transparent acrylic plastic I had laying around the rocket dungon with a couple 2" x 2" x 1/8" aluminum angle legs and some 4-40" hardware. In the beginning it had a 1/8" aluminum retainer strap squeeze bar which was quickly replaced with a 1/4" bar when I noticed i'd bent up the thinner strip during the first couple uses on micro PD models.
These Jigs works well with models from T2 (.246") diameter tubing to BT-55 (1.325"). I've never really tried anything larger as I'd think the body length and internal mandel weight might be an issue?
I've used the prototype jig on micro T2+ to BT-20 for compeitition style models with standard craft body tubes and double taper paper transitions models with great success to get no spin models with a simple internal mandel to keep the paper models from deforming in the straps.
My recently finished all aluminum model is 2 inches longer with an 8" v-groved holding section and 2-1/2" fin deck. The longer length helps making longer body models a bit easier to control.
While spring clips can be used to hold fins in place on the fin deck i've found them totally unnecessary with all but the largest overhanging fins.
If you have any type of saw that can be set up to cut a 45° angle, making these fixtures is a fairly simple chore. Wood would not be my choice as warping and moisture content unevenness would be a constant concern. Phenolic barrier board might be OK for larger models or fin jig construction?
While this jig doesn't work for models with far forward fins or long fin strakes it does well with most multi fin set models by working from the rear fins forward, sliding the body aft as you go.
Leather straps were chosen over other type fastings so the body could be held firmly as yet still allow it to be turned without releasing the pressure to align the next fin. The Deer hide I used could easily be replaced with any soft leather one might have laying around.
Below are a couple pics of the prototype & all Alum. micro Fin Alignment jig. I've had fun with this tool, I believe it would be a useful addition to the most any micro building bench.