Welcome To White Rose Engineering

Let us introduce the Throttle/Choke/Velocity stack Servo Kit.

Our newest addition is a machined billet aluminum plate that mounts between the intake manifold and the bottom of the carburetor on the DA 100 and 120 engines. This allows you to mount your throttle servo, and a servo to actuate the choke if you wish, right at the carburetor. This provides super precise throttle positioning. The engine comes back to the same idle position every time. No complicated and heavy linkage to fabricate and align. The system also incorporates a velocity stack on top of the carburetor which smooth out the air flow into the carburetor. We have noticed much better mid range performance with the velocity stack. The entire kit weighs less than three ounces, this does not include the servo(s).

The Rudder Master incorporates the advantages of spreading the vibration isolation mounts onto a wide foot print with the mechanical simplicity, accuracy, and torque absorption of a cog belt drive. The majority of the rudder loads are taken off the servo bearings and transferred into the aluminum tray through the bridge across the top of the assembly. Most of the shock loads from the rudder are absorbed by the belt rather than being transferred into the servo gear train.

I'm sure you have noticed that after synchronizing your rudder servos at the neutral and end point positions you would still hear the wine increase when you moved the rudder stick to positions other then the three synchronized points. This is because no two servos are created equal and there will always be some disagreement between them in their positioning. The Rudder Master's cog belt has just enough give in the belt to allow the servos to take the positions they want to take while bringing the rudder back to the same neutral position time after time. This is a real plus for anyone who flies in the IMAC aerobatic competitions.

We have done extensive testing with the super powerful JR 8711 servos and the results have been excellent. The strength of the belt, aluminum pulleys and aluminum pulley splines exceed the strength of the servo gear trains by several factors. The Rudder Master comes complete with everything except the servos including the double shear output arms. These arms will allow you to utilize pull/pull, push/pull, or a single push rod.

If you are planning on using one of the 400 in. oz. plus servos on your rudder you should consider our high torque servo tray pictured at bottom right. It is specifically designed to overcome the problem of poor neutral centering that comes with mounting 400 in. oz’s of torque on a 2” by 1” foot print through tiny rubber grommets. With this design the servo keys onto four studs that protrude from the bottom of the tray and are tapped to accept a 4-40 SHCS. The servo now becomes an integral part of the tray. Vibration dampening is provided by four Mil Spec rubber grommets at the four tray corners. This increases the mounting foot print for the servo by a factor of 8 which directly relates to your rudder returning to the same place every time. The tray and all mounting hardware weigh less than 2 ounces.

All servo trays feature a bridge to support the servo output shaft and absorb the shock loads from the flying surfaces. This takes the strain off the servo's gear train and bearings

ENGINE ACCESSORIES

Mixture Screws

Our latest offering is mixture adjustment screws for the Walbro WJ-71-1 carburetor. These will work on the DA 85, 100 and 120. They feature an Allen head recess rather then the standard screw driver slot. This makes it much easier to adjust the mixture, especially if you are doing it through a hole in the side of the cowling. There is a 45 degree taper leading into the allen recess as well. The Allen recess also allows up to 35 degrees of angularity so you don't have to be square onto the needle. The adjustment screws are pictured at bottom right.

We can also provide extended length (10") ball end Allen screw drivers that will reach through the cowl and easily reach the adjustment screws. The high end screw uses a 1/8" allen and the idle screw uses 3/32". If you have the right screw driver in your hand you cannot adjust the wrong screw.

DA Engine Mounts

We have personally broken lugs off our DA 100L 's engine mount and two other guys at our field have had the same problem with their DA 120's. DA says this is due to improper mounting and from an academic stand point that's true. The problem is we are not mounting the engine to a rigid flat surface. One answer is to acknowledge the airframes short comings and make the mount plate more robust. We have done that.

While we were at it we thought we would make the entire mounting system more robust and correctly aligned. Everything is machined to lock together with all mating surfaces parallel and true. This is the best way to keep things tight in a high vibration environment. We have two mount plates, one with no thrust offset and one with two degrees of thrust offset.

In an attempt to make one of the real PITA projects a lot easier we are offering a spinner alignment fixture. It keys into the mount plate and exactly replicates the locaton of the engine prop driver. You bolt your spinner back plate on the alignment fixture and position the whole shooting match right on the cowl spinner ring. Hot stuff the aluminum firewall plate in place and use it as a drill guide for the firewall bolts. Perfect spinner alignment in minutes. We have machined offset spacers to make any length you need down to 1/16" precision. There is a 1/8" spinner gap built into the alignment fixture.

Rudder Master with mounting hardware and servo arm.	$249.00

High Torque Servo Tray 5 x 5 with all hardware except servo arm.	$94.00

ENGINE ACCESSORIES
Allen Head Mixture Screws DA 85-100-120	$29.00
Allen Head Mixture Screws DA 150-170	$29.00
Extended Reach Allen Screw Driver Sets 1/8" & 3/32	$24.00
DA Engine Mount Plates
Heavy Duty Mount plate, DA 100 & 120	$46.00
Two degree offset HD Mount Plate, DA 100 & 120	$74.00
Spinner Alignment Fixture	$39.00
Firewall Plate	$24.00
Standoffs 1" long ( 4 )	$14.00
Standoffs 3/4" long (4 )	$12.00
Standoffs 1/2" long ( 4 )	$10.00
Stanfoffs 1/4" long ( 4 )	$10.00
Standoffs 1/8" long ( 4 )	$10.00
Standoffs 1/16" long ( 4 )	$10.00
Loctite 242 .017 fl. oz.	$ 4.50
		(plus shipping & handling)