I build a lot of planes. I probably put together one plane per month average. And most of the time I am assembling a prototype or some new thing and I have to develop the manuals and procedures, so I don't usually have a lot of time to make it neat or fancy. Also my planes get worked on a lot, so they must be easy to service.
I am assembling a new Giles, this one I plan to fly for a while since I really like the way a Giles flies. I thought that this time I would take you through the process, show the logic I use in deciding what to use and what goes where.
I also want to show that building a 35% or 40% plane is really no more complicated than a 50cc gasser. Much of the stuff you hear in the internet is meant to get you to buy things, often that you do not need. My goal here is to make this as simple as possible while remaining completely effective.
So here goes.
The first step is to get the engine mounted. Our new planes come with the firewall marked and an engine template, so all you need to do is line up the marks with on the firewall and the template and drill the mounting holes. We also sell a mounting kit that has the engine mounting spacers (standoffs, sort of, but more rigid and less expensive than machined standoffs) plus blind nuts and long socket head screws.
In this case this was the first plane of a new shipment so I needed to verify the location of the mark. As I expected it was off a little, so I mounted the engine once, found out how far it was off, then filled the holes and re-mounted it in the proper location.
Now that I have done this, you would know the correct location is UP 1/4" and to the left (viewing the plane) about 1/8". So make a new mark there and use that mark as your reference.
Also note the DA-100 template is marked along its side, not along the top. See photo.
I mounted the DA-100 ignition in the void behind the engine. The spacers are 1 3/4" deep which is plenty of room for the ignition.
I mount most things on foam and with zip-ties. Don't pull the zip-ties down real tight, that just increases shocks transferred to the ignition from vibration, instead leave them a little loose and surround the box on all sides so it can't slip out.
The firewall photo shows the initial mounting and then the revised location.
TF
< Message edited by rctom -- 2/11/2008 3:48:16 PM >
Posts: 11505
Joined: 2/25/2002 From: Central, CA, USA Status: offline
I like your selection in standoffs. Especially where longer ones are concerned that makes for a very good vibration damper and greatly reduces twisting loads from engine torque.
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If you can''''t fix it with a hammer, you have an electrical problem.
I like your selection in standoffs. Especially where longer ones are concerned that makes for a very good vibration damper and greatly reduces twisting loads from engine torque.
Yes, it's rock solid yet weigh almost nothing.
I make these things in 4 foot long strips. I cut a piece of lite ply the correct width for either a DA-100 or DA-85 (I do both) and then epoxy 3/4" square oak along each side.
Then when I need one for a customer or a plane I just set my table saw to the proper width (1 3/4" in this case) and slice off 2 pieces. They are exactly the same size and square, and I can cut to any width I want in about 2 minutes. I then use the template to mark the holes for drilling which is the most time consuming part.
TF
< Message edited by rctom -- 2/11/2008 4:13:02 PM >
Next comes the canister installation. We sell ply canister mounts that have plenty of material around the perimiter. The job here is to trim the mount to the right size. It should mount to the rear of the landing gear plate and also glue to the underside of the canister tunnel top. Here are beforee and after photos, and the completed setup.
This uses KS 86-4 canisters and 90mm drop headers with a flex section.
The mount is supplied with a section of silicone tubing. You need to cut pieces about 3/4" long and slip them in so the fingers of the mount go inside the tubing, the muffler is then suspended in the silicone with room for air to circulate around it.
Exhaust holes are provided to let the hit air and exhaust out, just trim away the covering. With these open you should not need to cut any hoiles in the cowl at all.
These are rear exit cans and are a touch longer than the provided holes, I will trim the rear edge and also install some silicone extensions on the tips to direct exhaust out of the plane. They also need stops against the rear of the cans to keep them from moving backwards, this is often left out and the first flight ends up with the cans disconnected from the header.
< Message edited by rctom -- 2/11/2008 4:12:14 PM >
After building so many planes I have learned to invest a little time in planning where to put everything. I know from experience that this plane will come out nose heavy, so I installed a little platform behind the canopy to mount the two A123 battery packs. I cut the corners off the leave a little window to route the wires.
I will be using 2 packs, one for just the receiver and the other will power the receiver and also the ignition. I have tested this in 2 planes and it works fine with my JR 2.4 ghz. radios.
I modified the battery packs and replaced the Cellpro charge jack with a standard JR receiver plug, and then added a long extension to carry power forward to the ignition. ON teh other pack I just left a servo connector there tro use when charging.
I made a little adapter for the Cellpro to charge through the charge jack on the ignition or through a standard servo extension. This is a little complicated to explain but is simple in practice.
I also installed a lite ply bulkhead to mount the receiver. This puts the receiver antennas up high which is where JR says to put them, with the satellite mounted in the bottom. Both switches will reach the receiver and the batteries without any wires hanging in the middle, very neat.
I mount the receiver on Velcro, this is plenty secure and as long as you don't tie it down with anything else it provides cushioning for the receiver to isoloate it from severe vibration.
Using two connections into the receiver like this is good for at least 12 amps in a burst, so a power box is definitely not necessary. Some of my testing has shown that some power boxes' internal circuitry actually limit the current to the servos.
Hooking up the ignition involved simply installing a switch in the pre-cut hole and hooking up to the power extension that I ran up the left side of the fuse.
I use these little plastic gizmos called cable stands, you can get them at any electronics store. Buy a bag of them, they are self adhesive and stick to wood very well. Then just use a zip-tie to hold cables in place and out of the way.
I use a choke servo instead of a kill switch, this is a great way to kill the engine in case the throttle linkage fails.
BTW with these switches I just use the litel hex head servo screws that I use for everything, I throw away the little mounting screws and backing plate that come with the switch.
Posts: 284
Joined: 8/17/2004 From: tulsa,
OK, USA Status: offline
Tom, If using a DA85 how would you route the one pipe and where would the exhaust tip come out. Do you have any pictures of your prototype that you had the DA85 on.
Also, with the DA85 does the cowl have to be cut to get proper clearance.
Tom, If using a DA85 how would you route the one pipe and where would the exhaust tip come out. Do you have any pictures of your prototype that you had the DA85 on.
Also, with the DA85 does the cowl have to be cut to get proper clearance.
Thanks.
The one pipe goes right down the middle. If you have a rear exit canister you turn the muffler a little and it exits in ethe rear corner. With front exhaust it comes out,... wait for it..., in front! You have to cut the cowl to make an exit.
I must apologize, I failed to take a photo of the first one with a DA-85. In factr I don't have any photos of any plane with the DA-85, I will correct this asap.
The cowl does not need to be cut except to clear the cylinder head and to allow cooling air over the head fins.
Posts: 35
Joined: 6/13/2002 From: Arlington,
TX, USA Status: offline
Tom, If you needed any picture of the Giles with DA-85 let me know. I can take a picture and email to you ( I don't know how to post the picture in forum )
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Giles build by Tom - 
