Tom's radio control model aircraft guide excelsior dave smith

Notes on buying an Excelsior 163

I first saw this model at the Dundee flying club one Easter and was very impressed by the 2 models (a 150 and a 163) which were flying there. A couple of e-mails to the pilots confirmed the model's abilities to fly well and land slowly, which, with our 66m runway that is a good feature. A couple more phone calls established that my Thunder tiger 91 four-stroke would not really be powerful enough so things got delayed whilst I decided upon the engine, ultimately deciding on the MVVS 91 from "Just Engines"..

The Build
The instructions are very comprehensive, but make sure you read them all before doing your own thing. Read the rest of this review, then go to http://www.dmac.org.uk and read the reviews of the Excelsior, Smart Move and CAP232. There are a lot of good installation photographs to give you help. THEN do your own thing :)

My advice, for what it's worth is:- do not cut the aileron servo holes until you cut the undercarriadge holes. Don't cut the 45 degree angle on the elevator until you have trial fitted the tailplane. Do not put in the rudder and elvator servos until you put in the wing bolt brackets. Then wait until you have the engine fitted so you can do a trial C of G check as the servos might need to go in the rear fuselage . The fibreglass cowl looks too narrow on first inspection, but if you carefully squeeze form top to bottom, it will expand latterly and fit the firewall. The control rods supplied are the 8inch / 2mm threaded wire ones, you supply the balsa rods. The wing mounting bolts go on the fuselage sides as shown in one of the photographs. When fitting the tailplane, mark the "Up" direction on the trailing edge as it takes a bit of work to get it horizontal. Likewise it is worth putting something on the main wing panels to indicate the top surface so you dont put the servo holes on the wrong face. Keep the foam cores that the wings come in as they are great for supporting the wing during the work you do on it. 2mm metal control rods bent to the correct shape and heated with a blow-torch make a neat job of cutting through foam wings. Don't overhead the rods or the foam will contract too much. Try cutting a bit of the scrap foam first. It is easier if you have someone to hold the wing for you whilst you cut out the notches. don't forget the piece of string to pull the servo wire throgh with. Wrap the tailplane in cling-film when finally epoxying in place.

This model comes with a pre-built fuselage with the firewall already set for down thrust, thereby saving a lot of building time. Although it does not say so in the instructions, you will need to hack into the foam to mount the servos. I also used servo bearers as suggested in the instructions. The only thing to be carefull of is that the wing mounting bolts do not foul the servos or control rods.

At first glance the fuse seems to be very weak and twists easily, but once the rear fuse has the corners and bottom added, it becomes much stonger.

CONTROL HORNS
I decided against using the control horns as supplied in the accessory pack as the holes were not coming over the hinge line to my liking. I checked out the Ripmax ones but although the screws would be okay if you fitted hardwood blocks, they would not do for a foam elevator. Eventually I used the Ripmax type where the self-tapping screws were long enough to go right through and into the backing plate on the other side.

Tailplane
Don't try to draw the outline of the tailpane onto the uselage. Instead,. draw it onto two pieces of paper then pin the 2 pieces of paper onto the fuselage. This way you can make sure the two holes you cut are roughly both at the same height. When you are about to epoxy the tailplane in place, cover one half with clingfilm before pushing it through the slot. That way the epoxy doesn't get smeared all over the tailplane.

Fin
How do you ensure the fin is perpendicular to the tailplane? Answer, cut 3 pieces of balsa about 4 inches long, and sand them to a point. Then stick them onto a set square, one at the top, one at the middle and one near the bottom. The one in the middle lets you see if your fin is bowed.

COVERING
Again I used pro-film all over. I use film hinges for the ailerons and elevator as I feel this gives better movement of the control surfaces. The only down-side is the second elevator has to be attached AFTER the tailplane is epoxied in place.

The Flight
Remember to compensate for the weight of the cowl if you are test flying with the cowl removed. My cowl when painted weighed in at 3 1/4 ounzes.

The balsa selection is first rate, very soft and very light. The cowl and canopy are very good and hardware pack had all the bits in it. (You'll need to dig out a couple of M3 countersunk screws for the wing mounting brackets though).

The model goes together quite well, especially if you can commit a couple of days to it. Doing it an hour each night after a 12-hour shift leads to a loss of continuity and mistakes. Althought the instructions are pretty comprehensive, I am not sure how a newcommer to building would get on. However, if you are reading this, and you check out the reviews on the Dundee web site, you should not have too many problems.

www.tomlaird.com

Wingspan	1630mm (64")
Length	1530mm (70") including spinner
Propulsion	MVVS 91 two-stoke mounted inverted,
Control	5 channel radio (rudder, elevator, throttle and 2 for ailerons)
Construction	Balsa, foam wing, covered with pro-film.
Web Site:	http://www.davesmithmodels.com

Notes on buying an Excelsior 163 I first saw this model at the Dundee flying club one Easter and was very impressed by the 2 models (a 150 and a 163) which were flying there. A couple of e-mails to the pilots confirmed the model's abilities to fly well and land slowly, which, with our 66m runway that is a good feature. A couple more phone calls established that my Thunder tiger 91 four-stroke would not really be powerful enough so things got delayed whilst I decided upon the engine, ultimately deciding on the MVVS 91 from "Just Engines".. The Build The instructions are very comprehensive, but make sure you read them all before doing your own thing. Read the rest of this review, then go to http://www.dmac.org.uk and read the reviews of the Excelsior, Smart Move and CAP232. There are a lot of good installation photographs to give you help. THEN do your own thing :) My advice, for what it's worth is:- do not cut the aileron servo holes until you cut the undercarriadge holes. Don't cut the 45 degree angle on the elevator until you have trial fitted the tailplane. Do not put in the rudder and elvator servos until you put in the wing bolt brackets. Then wait until you have the engine fitted so you can do a trial C of G check as the servos might need to go in the rear fuselage . The fibreglass cowl looks too narrow on first inspection, but if you carefully squeeze form top to bottom, it will expand latterly and fit the firewall. The control rods supplied are the 8inch / 2mm threaded wire ones, you supply the balsa rods. The wing mounting bolts go on the fuselage sides as shown in one of the photographs. When fitting the tailplane, mark the "Up" direction on the trailing edge as it takes a bit of work to get it horizontal. Likewise it is worth putting something on the main wing panels to indicate the top surface so you dont put the servo holes on the wrong face. Keep the foam cores that the wings come in as they are great for supporting the wing during the work you do on it. 2mm metal control rods bent to the correct shape and heated with a blow-torch make a neat job of cutting through foam wings. Don't overhead the rods or the foam will contract too much. Try cutting a bit of the scrap foam first. It is easier if you have someone to hold the wing for you whilst you cut out the notches. don't forget the piece of string to pull the servo wire throgh with. Wrap the tailplane in cling-film when finally epoxying in place. This model comes with a pre-built fuselage with the firewall already set for down thrust, thereby saving a lot of building time. Although it does not say so in the instructions, you will need to hack into the foam to mount the servos. I also used servo bearers as suggested in the instructions. The only thing to be carefull of is that the wing mounting bolts do not foul the servos or control rods.
	The wood supplied is very good and very soft, especially the leaing edges. Try getting some cenral heating pipe lagging foam and using it as protection.
This is the "Just-in-Case" area which eventually housed the 1100mAh battery to get the C of G into the correct position. There is a slot at the front edge to allow the battery lead to be routed past the servos.
ENGINE MOUNT Remember to offset the engine mount to the right, and up, to compensate for the thrust angles. (Check out the "hints" page at http://www.dmac.org.uk to find out more). I eventually used a Flair engine mount which has a good chamfers on the corners. As the engine was to be mounted inverted, I still had to remove 1.5 mm from one corner but this still left plenty of meat to the nearest mounting hole. Now came the tricky bit - how to fit the top two blind captive nuts when it was solid foam behind that part of the firewall.
	One solution is to cut 2 notches as shown in the photo, fit the blind nuts then fill in the notches with a couple of bits of scrap balsa. You can see how to pull the captive nuts into the wood in the photo. Use a large washer to spead the load, and a heavy leather glove in case the screwdriver slips.
At first glance the fuse seems to be very weak and twists easily, but once the rear fuse has the corners and bottom added, it becomes much stonger. CONTROL HORNS I decided against using the control horns as supplied in the accessory pack as the holes were not coming over the hinge line to my liking. I checked out the Ripmax ones but although the screws would be okay if you fitted hardwood blocks, they would not do for a foam elevator. Eventually I used the Ripmax type where the self-tapping screws were long enough to go right through and into the backing plate on the other side.
	WINGS If you are fitting a ply plate over the wing dowels, I would suggest doing this before putting the wing bandage on. I laid the wing servos flat and used a perspex hatch cover made from a CD jewel case. This lets me keep an eye on the servo arm retaining screw. I wasn't sure how to bore out the hole for the servo wire so I cut and lined a "U" channel as per Bruce Ogilvy's review. The servos are held in place by the cover, and a small amount of bath sealant.
Getting the 2-pronged elevator control rod at first looks impossible, but a couple of minutes with a razer saw sorted the problem. The pices of wood is then glued back in place once allowance has been made for the control rod slot. With hindsight I would probably have used a pair of snakes. As you can see I had to braze to rods together to get the required length.
Tailplane Don't try to draw the outline of the tailpane onto the uselage. Instead,. draw it onto two pieces of paper then pin the 2 pieces of paper onto the fuselage. This way you can make sure the two holes you cut are roughly both at the same height. When you are about to epoxy the tailplane in place, cover one half with clingfilm before pushing it through the slot. That way the epoxy doesn't get smeared all over the tailplane. Fin How do you ensure the fin is perpendicular to the tailplane? Answer, cut 3 pieces of balsa about 4 inches long, and sand them to a point. Then stick them onto a set square, one at the top, one at the middle and one near the bottom. The one in the middle lets you see if your fin is bowed.
FUEL TANK The instructions suggest fitting the fuel tank at the C of G if you are using a pumped engine, but a 14 oz tank can be fitted in the nose area. However the question is not how to fit the tank, but how to remove it. I found a long thin fuel tank made by Chart whilst rummaging in the local model shop. This would fit through the hole in former 2 but would result in a very long internal fuel line with greater chance of the clunk getting flipped forward in event of bad landing. Since I had decided against using a pipe, I felt the easiest thing was to make the floor of the fuel tank area removable. However, I was worried that the structure would be weakened so I epoxyed a 30mm wide strip of 1/4inch ply at the back of the area, and two 45 degree braces at the front. I had extended the hieght of the fuel tank bay to allow the tank to be set at the correct level with respect to the needle valve.
COVERING Again I used pro-film all over. I use film hinges for the ailerons and elevator as I feel this gives better movement of the control surfaces. The only down-side is the second elevator has to be attached AFTER the tailplane is epoxied in place. The Flight Remember to compensate for the weight of the cowl if you are test flying with the cowl removed. My cowl when painted weighed in at 3 1/4 ounzes. The Summary The balsa selection is first rate, very soft and very light. The cowl and canopy are very good and hardware pack had all the bits in it. (You'll need to dig out a couple of M3 countersunk screws for the wing mounting brackets though). The model goes together quite well, especially if you can commit a couple of days to it. Doing it an hour each night after a 12-hour shift leads to a loss of continuity and mistakes. Althought the instructions are pretty comprehensive, I am not sure how a newcommer to building would get on. However, if you are reading this, and you check out the reviews on the Dundee web site, you should not have too many problems.