Quote:
Originally Posted by Propworn
Clean cuts are easy once you get the layout down. Here is how I do it and it seems to work well for me.
Until you get the cowl mounted and clearance for just the motor block don’t try and cut out for anything else.
Determine what parts of the cowl need to be cut out for the engine and mount the engine to the airframe. Let’s say only clearance for the head has to be cut. Use low tack masking tape on the fuselage lined up so the centerline of the tape points to the glo plug. I use a 12 inch flexible rule and line up the center of the glo plug and as close to the center of the tape as I can then draw a line. Measure a distance from the glo plug to somewhere on that line on the masking tape. I mark the distance right on the tape. Take the engine out and mount the cowl. Line up that ruler on the line and extend it over the cowl and mark the distance where the glo plug should be. Lay out the cylinder head plus what ever clearance needed.
Now for the cut out. I have tried holding the cowl and using a dremel and I just cannot get nice edges as I find it hard to control. I mount the 1/2 drum sander from the dremel set in my drill press and change the speed to high. Angle the cowl and use the drum to penetrate the center of the cut out. Using two hands to control the cowl slowly work your way to the layout lines using the drum sander.
Use the tape and ruler method for any additional cut outs and locate small holes through the cowl for needle valves or choke wires etc.
I fly everything glo, electrics and gas. I got a real good deal on the kit some time ago and it’s to replace an old Spacewalker that I used to keep on hand when visitors show up with nothing to fly. I considered electrifying it as I have a nice AXI that would do the job however I have two of these new OS .91's laying about. Sooner keep the electric for something I will not lend out.
I found it to be the most complete ARF I have seen to date. The struts are metal; aileron and flap hinges are installed and glued. Fit and finish really blew me away for a factory ARF. It builds up better than many could build on their own. I wish they would allow a bit more covering on the edges and overlaps because once it separates you will never get it back again. Make sure you take your time and go over the whole thing with your covering iron and seal all edges. Start with a lower heat and increase it don't go for the higher temp right off the bat.
I will see about the gear as time goes on. Don't know what the weight is yet I hear even with an electric it builds nose heavy mine is and I will be moving things around a bit until I get the balance right. Servos I used a HS 425 on the throttle and 525's (high speed) everywhere else. One thing you might reconsider is the control linkage. This is an 80 inch span and therefore is considered giant scale. As such the minimum control rods should be 4-40 and they can refuse you flight privileges if you attend events with it. I would not worry about using small servos the wing loading is quite low.
Hope this helps.
Dennis
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Thanks Dennis as one of the things I was looking at in the manual was at what point are they going to tell me to glue the control surfaces in.I haven't had time to pull it completely out just a quick look over I must agree with you that its a very complete and well built ARF.I have been using the paper temp methed of placing on the sides of the fuse and marking out plugs,carbs,exhaust pipes and that has worked for me in the past.I found using the dremel with a sanding disc better as well than using the cutter but what I have done is use the cutter first to ruff cut and then sand out the shape.I find that by doing it that way I get less dust even though I use a shop-vac when ever I sand or cut with a power tool.Thanks for the heads up on the covering as I'm new to the ARF seen as most of my stuff has been either kit or scatch built.Its hard to build it for what one can buy them for today as long as one doesn't mind seeing a couple of the same planes on the flight line.John