Radiator rev 1.1 The SE5a s radiator is one of the most recognized radiators in WW1. It is one of the components that defines the SE5a. The original SE5a has seen multiple radiator designs used during manufacturing. The kit includes the later version which has the two banks of shutters on each side of the propeller. The radiator has a lot of different parts that work together and must be assembled properly. Take some time to inspect the parts and understand how everything goes together. The assembled radiator with shields, shutters, etc. will be painted as one unit. The honeycomb material will not be painted. The radiator can be removed from the plane like the original. Note about your engine selection. The prototype used the DA-85 engine (shown on plans) with a prop 1-1/4-inch extension and custom muffler, see plans for further details. This engine solution worked well as it eliminated any radiator modifications. Other engines will work, although I have not explored all solutions. Just note that you might have to do some minor radiator modifications as there are two main issues you should be concerned about when selecting an engine; the radiator thickness and prop shaft location. You need to decide on where your prop shaft will exit the radiator and your engine orientation. Just remember other parts of the plane connect with the radiator so don't get too happy with modifications. Don t forget that the dummy engine block starts about 3/4-inch behind the radiator and the upper engine metal hoods secure to the radiator top as well. You will start with the radiator wood frame first. It is important that the frame be built straight with no warps. The honeycomb, shutters, music wire, etc. need to fit rather perfect. Just take your time and understand what you are doing. Having the fuselage built up will help you check the radiator fit as well. Plan sheet one shows the front view of the wooden frame. Gather all the wood parts shown in the front view. Lay them in position over front view radiator plans. Understand their correct orientation and position. See photo below
Assemble these parts together without gluing. They should sort-of snap together. Parts #5.5 and #5.10 have a laser etched arrow which indicates the front. Ensure the arrow is pointing towards the propeller. The four vertical pieces #5.6-5.9 have three holes for each G10 clip #1.3. These holes should be closest to the propeller or the front of the radiator. Ensure you have everything oriented correctly. Disassemble the parts. Using a wood glue start gluing these parts together. Start at the bottom working your way toward the top. Try using some support blocks holding the parts in position. Don't get too happy with glue. Keep glue out of rivet holes and the two inner slots for parts 1.2. See photo below
Continue gluing the remaining top parts ensuring the angled piece is glued well. Set aside and let dry. See photo below Three balsa blocks #5.225 and #5.226 are used to simulate the header tanks. (I forgot to take photos of them being installed and sanded. Although, the photos below will help you with this area.) Note these blocks are wider than the wood frame by design. They need to be flushed with the top plywood piece #5.5 leading edge. The rear of these blocks will extend pass the top plywood piece #5.5 but that is by design as the rear will support the upper metal engine hoods, hinge and cable. The center block will be covered with a metal sheet #4.6 the two outer balsa blocks #5.225 will not be covered with metal. The center block has a 1-inch diameter dowel #5.15 used in it to locate the correct height of the brass radiator cap #4.39. The top plywood frame piece #5.5 locates that dowel. Set the center balsa block #5.226 in position on the wooden frame having it flush with the leading edge of plywood #5.5. Use a pencil and mark the location of the dowel on the bottom of this balsa block. Remove the block. Using a 1-inch diameter drill bit, drill a hole for the dowel all the way thru the balsa block. The radiator cap is wider than 1-inch. You need to use a 1-1/2-inch drill bit such as a Fostner bit, drilling down a 5/8-inch centered into this 1-inch hole. That would give a slight clearance for the radiator cap to sit on the dowel correctly. Drill this wider hole now. Glue the center balsa block to the wooden frame now. Carefully, sand the front curve into this balsa block. Do not sand the rear, leave as is. Reference the plans. Once satisfied with the sanding insert and glue the dowel in place. Remember to keep the dowel flush with the bottom of the top plywood piece #5.5. Test fit the radiator cap #4.39. It should look like the photos below. Make any adjustments as needed. Remove the radiator cap for now. You can permanently glue in place after radiator is painted. When the radiator is finished some of the dowel under the radiator cap should be visible. Glue the two outer balsa blocks in place now. Carefully, sand them to shape matching the plans. These blocks are
slightly lower than the center block. See plans. Also, these outer blocks should slope down to the outside and curve towards the front matching the front curve in the center block. See photos below
Trim the metal cover to shape. Use a Foster drill bit 1-1/2 diameter to cut the center hole for the radiator cap. This is easily done by drilling in some scrap wood first then lay metal over that wood and drill thru the metal into the wood hole. Bend the front edge 3/8 inch. Use epoxy to hold the front edge in place then wrap the metal around gluing it into position. This would be a good time to sand and seal this wood frame getting it ready to paint. Use a wood primer to do that getting the finish you desire. Remember this wood frame should look like metal as the original was metal. The prototype used Plastikote sandable primer grey color. This color helps highlight any imperfections. Locate parts #1.1 thru 1.4. These G10 parts are messy as all G10 parts are. You need to lightly sand the edges and the outside. Ensure you understand where these parts go on the radiator frame. Parts 1.1 and 1.2 are not equal. Part 1.2 has a slot on the bottom which this part goes on the inside of the radiator. See plans. Test fit these parts now using the aluminum rivets 6.1. Ensure the rivet head seats all the way down onto the G10 fitting. After you have these parts in position use some thin CA glue to
secure the rivets and G10 parts to the wooden radiator frame. Don't get happy with the glue just ensure they won't vibrate loose. You can use the aluminum tube #4.3 to align the four radiator mount brackets. Aluminum tube #4.3 can be trimmed to length. This tube secures the radiator bottom in place. See photos below
You can test fit the wooden frame in place onto the fuselage ensuring the mount brackets align to the radiator bracket #1.6 on the bottom fuselage longeron. The aluminum tube #4.3 should extend about an 1/8-inch past the G10 mounting brackets. The mounting brackets should be on the outside of the radiator bracket. See photo below The two aluminum honeycomb grills #4.1 are cut a wee-bit larger than needed. They should fit in your wooden frame snuggly. They should not alter your wooden frame. The shutters and shutter frame will cover some slight mistakes but at this time cut the honeycomb grill to size test fitting into place. You can use some tape to help you cut the honeycomb straight. Using a metal bandsaw will cut the material. Take your time. Make a right and left version. The honeycomb grill should be flush with the front of the wooden frame. See photos below The two center metal shields #4.7, 4.8 are held in place with aluminum clips #4.43 that are epoxied in place using brass nails #6.59. Remove these pieces from the aluminum sheet removing any burrs. These shields are very visible. Try not to put dents in them. They can be removed after installation like their full scale counterpart. Test fit these two shields in place see how they align to the G10 clips 1.3. If there is some slight mis-alignment you can carefully file, the aluminum shield
some. Notice the pulley slot on the bottom shield it should be on the right side when looking at the radiator. The two shields have two tabs that interlock them together. These tabs are at the top of bottom shield and the bottom of the top shield. You might need to slightly file the tabs to ensure then seat well. See photo below The lower shield #4.8 needs to be bent around the radiator bottom. With the shields in place mark the back of the lower shield where it passes the radiator plywood base #5.10. It should be about 1-5/16-inch above the bottom edge. See photo below Using 3/32-inch music wire or rod place it along the marked line you made securing the aluminum and bend 90-degrees. Use the end of a sturdy table or something similar to that. Make sure you bend the aluminum the correct direction ensuring the pulley opening is on the right hand side when looking at the front of the radiator. Take your time, check your work before you bend the aluminum. You have one try to get it right. See photos below
Test lower shield in place. It should be snug to the plywood base. See photo below
Remove the lower shield from the radiator. Insert the 18 brass nails #6.59 thru the front of the lower shield. See photo below In this step you will add the six aluminum clips #4.43 to the backside of the shield adding epoxy to secure the nails and clips in place. Don t get happy with the epoxy although ensure these pieces won t vibrate loose. To help hold the nails in place and flat onto the shield use some masking tape on the top of the shield and if needed slightly pull on the nails with pliers seating the head flat which keeps the nail straight. The nail head needs to be seated flat against the shield. Use some plyers pulling the nail into place. Add the clips making sure they are straight and not angled. Add the epoxy. Trim away any visible or extra epoxy after it dries. See photos below
The clips need to be bent now 90-degrees toward the propeller. Bend the clips vertical making sure they bend immediately at the edge of the shield. See photos below Repeat the clip / nail process above for the upper shield #4.7 now. Install the two shields into the radiator. The clips should align to the G10 clips. Ensure everything fits well making any adjustments as needed. This completes the shield assembly. Shutters and frame The shutters can be operational (open/close) if desired. Most likely you will fly the plane with the shutters opened. The shutters can be left unpainted or painted depending on your subject. Most of the shutters were left unpainted. You want to assemble these shutters with engine vibration in mind. The radiator uses two banks (rows) of shutters. Each shutter bank has 30 shutters. There is one main shutter in each bank. That shutter is different than the other common shutters. The kit includes two extra common shutters just in case you need them. You will create 60 shutter assemblies. It is very important you take your time and be very accurate with these shutters. There isn t too much room for error. Remember you will make a right and left hand bank of shutters. The common shutters use a music wire, aluminum tube and nails. The main shutters will use a larger music wire, aluminum tube coupled together with a pulley. You will create the common shutters then the two main shutters. Once you have the shutters and frame assembled they can be installed onto the radiator. Assembly of the shutters takes time and accuracy. Locate the shutters in the supplied metal sheet. The shutters are held in place with two micro tabs. Remove all the shutters by twisting the shutter out of the metal sheet. Carefully, use a metal file removing any metal burrs left at the micro tab area. See photos below
The shutters with one long opening versus two openings are the main shutters. The first thing you will do is bend the end of all the aluminum shutters #4.36. You need to make thirty left-hand and thirty right-hand shutters which includes one main shutter (long opening). Each shutter bank will have one main shutter and twenty-nine common shutters. It is very important that you bend the shutter end properly as it will align the shutter to the shutter arm #1.8 as well as locate the pivot wires #4.31 and #4.56 correctly. Each shutter has an end that is chamfered and two holes. This is the end that will be bent at 90 degrees. The larger hole will be used for the pivot wire and the smaller hole will be used to attached the shutter to the shutter arm. You want to take your time and build thirty right and left hand shutters. Make sure you understand how the shutters are oriented when installed. The bent shutter end is on the port and starboard side of the shutter frame away from the prop shaft. When the shutters are in the open position the chamfer edge should be pointing aft or towards the pilot. You will notice each shutter has a notch and a small cut line. This is where you will bend the shutter. See photo below
Bend sixty shutter ends now making thirty left and thirty right hand shutters. Ensure the bend is straight and crisp. The bent end should be perpendicular the rest of the shutter. Another words the bent end should not be crooked. You can bend the shutter end over a piece of steel or something similar. See photos below The common shutters use music wire #4.31 as the pivot wire. You will need to make 58 pieces that are 2-1/2 inches long. Using a brake or a dremel cutoff wheel cut the music wire and remove any metal burrs from the cutting. The aluminum tube #4.35 goes into the two open slots found in the common shutter. Slide two tubes onto one of the music wire pieces you just cut. The music wire goes into the large shutter tab hole and the tubes will fit into the two slots. Ensure the tubes and music wire is seated properly in the shutter. See photos below
These aluminum tubes need to be permanently secured in place. Use some scrap wood to lift the shutter assembly off the building table. Turn the shutter assembly upside down where the shutter tab is off the edge of the wood and not touching the building table. You want to ensure the tubes are aligned in the slots as well as the music wire is aligned with the bent tab. Use some epoxy putty such as Oatey Fix it Stick which plumbers use. A 4-ounce tube is about $6. A pretty common putty that should be available at multiple locations. Or you can epoxy these tubes in place. Think about vibration. See photo below Add the putty to the backside keeping the tube and music wire centered. Don t get happy with the putty but enough to keep the tube in place. You can use a tooth pick to remove any excess putty. Let dry and lightly sand. Don t get in a hurry as this assembly really needs to be built correct. See photos below Repeat the above process for the remaining 57 common shutters. Yes, I know that s a lot of shutters but you can do it, just take your time. The main shutter will be done next.
The main shutter uses a larger diameter piece of music wire #4.56 as well as aluminum tube #4.89 and brass tube #4.37 which you need to cut all to length. The two main shutters share the same music wire. The pulley #3.98 is mounted onto this music wire. Cut a piece of #4.56 music wire 9-inches long. This length will be a wee-bit longer than you need but it s always better to trim than to cut short. Use a dremel cutting wheel or something similar cutting this music wire to length sanding any metal burrs off the end. Cut aluminum tube #4.89 to the same length of the opening found in the main shutter #4.36 which is 1-61/64-inches long. You can overlay the shutter on the aluminum tube then mark with pencil. See photos below Cut a piece of brass tube #4.37 one-inch long. Following the epoxy putting instructions above secure the aluminum tube to each main shutter. Use the #4.56 music wire you just cut to help secure the aluminum tube in place. Once the putty or epoxy is hard sand smooth. The next step is to attached the shutters to the shutter arm. If you are not planning on making the shutters function (open / closed) then you can permanently glue the shutters and nail to the shutter arm in the open position. The next paragraph instructs the operational shutter process. You will attach the shutters to the shutter lever arm then that assembly is attached to the shutter frame on the radiator. The prototype did not use operational shutters.
Shutters are secured to the shutter G10 lever arm #1.8 using nail #6.17. The idea is that the shutter lever will move vertically up and down which opens and closes the shutters. Which means the nail and the lever arm cannot be glued to the shutter itself. Insert the nail into the shutter seating the nail head properly then thru the lever arm. Carefully, glue (CA thick) the nail to the lever arm but not the shutter. Don t get happy with the glue, use a toothpick. It doesn t take much to secure the nail in place. If glued properly the nail head should be seated flat and the shutter should rotate freely. Reference the plans on the proper shutter orientation with lever arm. The shutter lever arms are located on the outer right and left of the radiator. Not near the propeller. Trim the nail once it is secured in place. Remember that the main shutter is the fifth shutter from the bottom of the lever arm and it is the fifth shutter in the shutter frame (from the bottom). Do the remaining shutters. See photos below
Make sure that the shutters can move freely on the lever arm. File all nail stems flush with the lever arm. See photo below The G10 shutter frame pieces #1.32 and #1.33 should be assembled on the radiator. The horizontal shutter frame pieces #1.33 is designed to be a little longer than you need just in case you did not make the radiator frame exact. Every shutter will be installed using the music wire rods you cut earlier.
Using screws #6.74 and hex nuts #6.63 install the two outer shutter frame pieces #1.32 to the inside of the G10 tabs #1.3. Ensure you have the frame oriented correctly meaning the large rod hole for the main shutter is near the bottom of the radiator. The hex nuts will go on the outside of the frame. If your alignment is slightly off adjust the hole in the tab leave the G10 frame holes as is. Note that the two center metal shields should be part of this installation. The G10 frame pieces should be straight not bent. See photos below
Install the shutters with lever arm. The shutters should be oriented with the lever arm away from the propeller. Start at the top and slide the music wire rod thru the shutter frame, shutter and the other shutter frame. The shutter and lever arm should clear the screw heads. Take your time. See photo below
The plastic pulley #3.98 will need to have the center hole enlarge so the music wire #4.56 can fit into this hole. Using a 3/32-inch drill bit drill the center of the pulley. See photo below The plastic pulley #3.98 should be painted brass now. Slide pulley and the brass tube #4.37 onto the music wire #4.56. The pulley should be oriented as seen below. The brass tube simulates the coupler used on the full scale. The full scale has the music wire #4.56 cut in half. Most likely you will keep this rod in one piece. See photo below
Slide this music wire in place aligning the pulley and brass tube in position per the plans. Carefully, use a little thin CA glue securing their locations. See photo below The radiator is secured to the front top longeron using stay tubes. These two brass tubes #4.4 attach to G10 fitting #1.4 and the front top longeron #5.1. Cut two 3-3/8-inch long pieces from the brass tube #4.4. Using a pencil or similar make a mark 3/8-inch from both tube ends. Crush one 3/8-inch end first then rotate the brass tube 90-degrees crushing the other end. See photo below
Using a 7/64-inch drill bit drill a hole 3/16-inch off the tube edge. This is the end that will attach to the G10 fitting #1.4. See photo below Using a 5/64-inch drill bit drill a hole 3/16-inch off the tube edge. This is the end that attaches to the front top longeron #5.1. See photo below Remove any burrs from the drilling. Test fit in place bending the end that attaches to the front top longeron. These tubes should be painted semi-gloss black. Paint them now.
Using screws #6.3 and hex nuts #6.9 attach the stay tube to the G10 fitting. The hex nut should be on the backside of the G10 fitting. Using screws #6.2 secure the stay tube bottom to the front top longeron. Bend brass tabs as needed. See photo below