Restoration of a 1917 Detroit Model 68
Transcription
Restoration of a 1917 Detroit Model 68
Restoration Restoration of a 1917 Detroit Model 68 November 11, 2007 – December 11, 2010 By Donald R. Davidson #1 – THE 1917 DETROIT ELECTRIC Sometimes it is best to start a story at its end rather than the beginning, and I will do that here. These are pictures of the completed Detroit taken on December 11, 2010, just following its first outing under its own power. continued next page 16 Current EVents / September 2014 Restoration And now back to the beginning. Here are three pictures taken on November 11, 2007, the day I purchased the car, and before its restoration. They were taken in South Carolina at the home of Ray Adcock, the previous owner. In the mid 1950s, Ray bought the car from the original owner also from South Carolina. Being an avid car collector, Ray painted the car and got it running. Over the next 50 years he took it to many antique car events. In the top picture below, Ray is on the left and I am on the right. In the background is his current project, a 1941 Ford. Previous Owner Ray Adcock – Left New Owner Don Davidson – Right November 11, 2007 #2 - THE INTERIOR Following are some photos of the restored interior. I restored the trim around the door windows in a natural wood finish. In stripping the original black paint off the wood I found the grain to be too beautiful to repaint, so I stained and varnished it. I also thought the cut glass flower vases that I mounted on the door frame pillars between the windows made a nice touch. I found them at an antique car flea market in Pennsylvania. Before the new upholstery was installed, I replaced all the wiring behind the old upholstery with new wire having a cloth outer cover resembling the original. This included wiring for the dome light, tail light, headlights, and horn. continued page 18 September 2014 / Current EVents 17 Restoration Detroit Continued from page 17 continued next page 18 Current EVents / September 2014 Restoration Ernest Hillier of Salem, NY (northeast of Albany) did the interior upholstery (Previous page). It was done in a wool broadcloth or whipcord as was the original. Below are some shots of what he started with. Below is a photo of the steering tiller (long lever) activated by the driver’s right hand, and the speed control lever (short lever above the steering tiller) activated by the driver’s left hand. The driver sits behind the levers facing the front of the car. The car turns left if the steering tiller is pushed away from the driver, and right if it is pulled toward the driver. The size of the driver’s belly is the only limit on how sharp a right turn can be made! Speed Control Lever Steering Tiller continued page 20 September 2014 / Current EVents 19 Restoration Detroit Continued from page 19 The speed control lever adjusts the car’s speed. If it is pushed away from the driver the car will go faster, and if it is pulled back it will go slower. The horn button is located at the end of the speed control lever grip. It is activated by the thumb on the driver’s left hand. It is not obvious from the photo on the previous page, but I had to make a new grip for the steering tiller to replace the missing original. It was made to match the existing original speed control grip as the instruction manual showed them as being almost identical. I turned the new grip on a lathe using a piece of black Nylon which I polished. In the photo to the right, the original speed control grip is on the bottom, the new tiller grip is in the middle, and the Nylon bar from which the new grip was cut is on the top. The rear window latch was missing completely so I remanufactured a new one based on an original from a 1918 Detroit. The photo to the right shows the new latch. #3 - THE BATTERIES AND THEIR COMPARTMENTS Following are some photos of the Detroit’s front and rear battery compartments. The front compartment is located under what normally would be the hood of a modern car. The rear battery compartment is mounted in what normally would be the trunk. Each holds seven modern six volt deep cycle golf cart batteries (lead acid) connected in series making two separate forty two volt battery packs. The original batteries that came with the Detroit were also lead acid, but would have looked very different from today’s familiar automotive batteries. Instead of packaging six two volt cells together into a separate twelve volt battery, as with modern car batteries, they packaged each two volt cell separately in its own hard rubber “jar”. The resulting twenty one jars (forty two volts total) in each of the two battery compartments were grouped together in Oak boxes. There were three of these boxes in the front compartment and four in the rear. To accommodate the modern lead acid batteries, I had to design and build a framework to hold them in place complete with fifteen hold down straps to keep them from bouncing around when trailering the car. I ended up using over twenty feet of two inch angle iron and machining over fifty individual parts which required more than twelve machining operations per piece. The batteries should give the car a total driving range of about sixty to seventy miles on a single charge. Their life expectancy should be around five years. 20 Current EVents / September 2014 New Tiller Steering Grip Original Speed Control Grip New Rear Window Latch I then cut twelve wire battery cables from 0/1 size wire that had a cloth outer covering giving an appearance similar to the originals. Each one had to be the correct length to give the proper battery wiring sequence. Even though I used stranded wire, the copper is still about 3/8” in diameter, and in tight places very hard to bend making this job a real chore. The proper left hand and right hand terminal clamps were then soldered onto the end of each cable. Below is a picture of the completed front battery compartment. Completed Front Battery Compartment continued next page Restoration Below is the completed rear battery compartment. Directly below are the before and after photos of the front battery compartment without the batteries. Completed Rear Battery Compartment Before — Front Battery Compartment In the above photo, the red box in the middle of the rear battery compartment is the eighty four volt battery charger. It is permanently mounted on the car and has a twenty five foot power cord so the car can be charged on the road if necessary. The small twelve volt motorcycle battery mounted behind the charger powers the new directional signals I installed for safety, and the horn. The original horn was powered by forty two volts and was missing when I bought the car so I used a horn of the period that worked on twelve volts. I will have to keep my eye out for an original forty two volt horn at flea markets. After — Front Battery Compartment The following three pictures show the details of the battery hold downs continued page 22 September 2014 / Current EVents 21 RESTORATION Detroit Continued from page 21 Before — Rear Battery Compartment After — Rear Battery Compartment Above are before and after photos of the rear battery compartment. on most of the components. None the less, each mechanical system had to be dissembled and each part cleaned, examined for damage, repaired if necessary, and reassembled. Starting with the rear axle I removed the differential cover only to find it full of a thick tar like grease (photo on left below). The differential was cleaned (photo on right below) and filled with modern gear oil. As you can see there was a lot of damage to the battery compartment’s wood floors due to spilled battery acid throughout the years. All of this wood had to be replaced. #4 – THE MECHANICAL SYSTEMS Turning my attention to the mechanical systems, the first order of business was to make sure everything was in proper working order. As with many antique electric cars, my Detroit apparently had very little use as almost no wear was found Differential – Before 22 Current EVents / September 2014 The seals on the outer axle bearings were the traditional antique heavy felt washers. I modified the seal holders and installed modern seals as I didn’t want any differential oil leaking onto the nearby brake linings. The photo on the left on the next page shows the installation of the new seals into the modified holders, and the one on the right shows the new seal assembly being installed on the rear axle. Differential – After continued next page RESTORATION Modified Oil Seal Holder New Oil Seal Assembly Modern Oil Seal Rear Axle Bearing I then dissembled and cleaned the brake mechanisms, the front axle bearings and spindles and after repacking the bearings with grease, went through the rest of the mechanical systems. The photo below shows the car in the middle of disassembly during this process. Before – Brake Ratchet Mechanism After – Brake Ratchet Mechanism Car Being Disassembled During Restoration The two photos at the right are typical of what I found. In the photo immediately to the above right, the parking brake ratchet mechanism is being dissembled. After disassembly and cleaning, a new bronze bearing was made replacing one that had worn out. Also, a worn ratchet pawl was repaired and all the parts were painted. The photo on the bottom right shows the finished parts ready to be reassembled. #5 – FABRICATING THE MOTOR BRAKE One component completely missing when I purchased the car was the motor brake. This is mechanical brake mounted directly on the motor shaft just behind the motor and before the drive to the rear axle. It is activated by the speed control lever shown in the photo on top of page 19. As described earlier, pushing the control lever forward increases the continued on page 24 September 2014 / Current EVents 23 restoration Detroit Continued from page 23 speed of the car. Pulling the control lever backwards reduces the car’s speed until current no longer flows to the motor. If you continue to pull the lever backwards, the motor brake will engage. So in theory, you can accelerate, decelerate, and apply a brake with the simple movement of one hand. In addition there is a traditional brake shoe and drum mounted on each of the rear wheels. These are activated by a pedal on the floor and provide the majority of the cars braking power. A friend had a 1918 Detroit nearby and I spent about five hours under his car taking critical dimensions and over a hundred detailed photos of his original motor brake system. I then reverse engineered the design and made several precision layout drawings showing the relationship of all the components to each other and to the existing motor. The corresponding detail drawings were then made with the precise dimensions for each new part. In all I had to draw and fabricate over seventy pieces that had to look and function like the original brake system. mechanism was destroyed as it hit an obstacle in the road, and had to be removed. In the process, the brake drum mounting flange was bent. The bent flange is a rather complicated piece made from a casting with multiple internal keyways machined to mate with external keys machined directly into the end of the motor shaft. It would be a difficult part to recreate from scratch. Considering how I might repair the existing part, I decided not to try bending it back into shape for fear of breaking it. Also, the flange was not thick enough to machine the mounting surface back to be true with its axis. So instead, I designed an intermediate plate that I fastened to the flange and then machined perfectly true to the motor shaft. This worked out quite well as the new drum has less than .005” run out after being mounted in place. The new motor brake is now assembled on the car and performs exactly as the original would have. Directly below is a photo of the new motor brake mounted on the motor. Newly Fabricated Motor Brake The first piece fabricated was the brake drum. An old cast iron brake drum of a similar size and shape to the original was found and modified to fit. This was the first step as all the other parts had to be designed to properly fit the new drum. When the drum was first installed on the original mounting flange on the motor shaft, I found out why the brake mechanism had been removed. The mounting flange was bent making the drum wobble front to back by about +/- 5/16”. This would have bound up the original brake and not allowed the car to move. The mechanism for the motor brake is larger in diameter than the motor making it the lowest point on the car. I imagine sometime in the car’s history the brake 24 Current EVents / September 2014 The next photo is the original I copied. An Original Motor Brake continued next page restoration The next six photos show some of the steps in fabricating the new motor brake parts in my shop. Directly below, the main mounting plate (left), and the brake shoes (right) are being machined. Main Mounting Plate Brake Shoe The brake shoe mounting bracket shown in the next two photos was machined out of a solid block of steel as were many of the other parts. Brake Shoe Mounting Bracket Directly below are the final products. The completed new motor brake assembly (left) and the new intermediary pivot mechanism (right). Completed Motor Brake Assembly Intermediary Pivot Assembly continued on page 26 September 2014 / Current EVents 25 restoration Detroit Continued from page 25 #6 – THE ELECTRICAL SYSTEMS The switching for all these combinations Turning my attention to the electrical systems, I removed the cover from the motor, is made by a turning a drum which roand found the commutator and brushes to be in excellent condition and not needing tates either forward or backward as the any further attention (photo directly below). speed control lever is moved either away from or toward the driver. On the drum are mounted several copper plates with Motor Commutator very specific shapes that contact eight copper fingers. As the drum is rotated, the copper plates make contact with the proper fingers to achieve the desired connections and thus the different speeds. The drum, its copper plates, and the contact fingers are clearly shown in the photo below. Motor Brushes The main power wires to the motor and speed controller were also found to be in usable condition and were shrouded in shrink tubing for added insulation. The speed controller was then taken apart, and completely rebuilt. As described earlier, the Detroit’s speed is regulated by pushing the small arm above the steering tiller away from the driver (see photo on page 19). The father away it is pushed, the faster the car will go. There are five and only five speeds available, each one being separated by a distinct mechanical detent. The first will get the car going about two or three miles per hour while the last allows the car to develop about twenty five miles per hour. Two of the five speeds are achieved by connecting the front forty two volt battery pack with the rear forty two volt battery pack in either series or parallel (42 volts or 84 volts to the motor) by an ingenious switching mechanism shown in the photo to the right. The same switching device can also connect the motor’s two field windings in either series or in parallel 26 Current EVents / September 2014 with each other. The resulting combinations of voltages and wiring of the field windings result in four different motor speeds. The fifth utilizes a separate resistor for the first or starting speed. Considering the technology available at the time, the Detroit’s method of speed control is a fairly efficient use of the stored electrical energy. None of the energy is wasted by dumping it into idle resistors to reduce the current to the motor and thus its speed. This would occur if a variable resistance (Variac) type speed control were used which was about the only other technology available at the time. The only exception is the additional resistor used in the first or starting speed, and this position would be used only briefly. 8 Copper Fingers Copper Contact Plates continued on next page restoration Through the years, most of the fingers had worn quite a bit. I silver soldered copper to the bottom of the worn fingers, and then reshaped them by hand to give perfect contact with the copper plates. Auxiliary springs were made for each finger to aid the original springs that had lost their tension. The next two photos show the restoration of the speed controller fingers. On the left, additional copper is added to the bottom of a worn finger in preparation for silver soldering. To the right the soldered copper is being shaped by hand. Adding Copper to the Worn Contact Finger Reshaping the Contact Finger Below is a photo of the speed controller before restoration. Looking down on top of the controller with its cover removed. The Speed Controller Before Restoration The head lamps, interior dome lamp, and tail lamp all work on forty two volts and all the bulbs had to be replaced. Where does one look for forty two volt, bayonet type, automotive bulbs? Well, my first try was McMaster Carr and to my surprise, they had exactly what I needed. As a side note, the head lamp bulbs have a single filament which is wired to give both a bright setting and a low or dim setting. How did the engineers at Detroit do this? They connected the two bulbs in parallel for the bright setting, and in series for the dim setting. Now that is both clever and efficient! continued on page 28 September 2014 / Current EVents 27 restoration Detroit Continued from page 27 Another surprise came when I removed the cover from the dome light. Inside was the original Edison Mazda bulb complete with the Edison label and the pointed tip on top. The filament still appears intact, but I decided to replace the bulb anyway, and to keep the original in a safe place. Was this bulb shipped with the car from the factory? It could have been as this light is rarely used. Below is a photo of the Edison bulb found in the dome light. Original Edison Light Bulb As seen in the photo below, the horn button is mounted on the end of the speed control grip. The original button was missing one of its electrical contacts which I had to recreate. It now works as well as it did in 1917. for easy viewing. Its primary function is to show the driver how much charge is left in the batteries, and in a sense is used like a gas gage in a modern car. As the batteries are being charged, the black needle pointed at 6 in the photo moves to the right. When they are fully charged it will be opposite the “Full” mark just below the number 1 on the dial. As the car is driven and the batteries discharge, the needle moves back toward the left. As it approaches the stationery red hand or “empty” marker the driver knows it is time to recharge the batteries. Recharging can take as much as twelve hours so it is advisable to be close to home well before the batteries approach “empty”. 28 Current EVents / September 2014 #7 – THE WINDOWS When I purchased the Detroit, most of the glass was the original plate glass which in an accident can become deadly. Also, one of the four curved corner windows was cracked, and another had been replaced with Plexiglas. Being cautious, I decided to replace all the windows with safe materials. The front windshields were replaced with laminated safety glass as found in The second gage on the amp hour meter modern automobile windshields. is an amp meter which is located in the arched opening toward the bottom of For the two door windows, and the the gage dial, and is marked “current rear window, I had tempered glass rate”. It reports the amount of electri- fabricated. This is also used in modern cal current the motor is drawing at any car door windows and when broken given moment. This alerts the driver to breaks into very small harmless pieces. any unusually high current draws that may signal an abnormal condition in the Deciding what to do with the four motor or wiring. curved windows was not as easy. I received two quotes of $5,000 to have In restoring the amp hour meter, I the four windows made in safety glass. removed its cover and examined the In addition, I talked to several electric car owners that tried this, and learned that making the proper curve and fit was at best very difficult. The glass contour, and outside shape had to be coordinated perfectly. In talking to one car owner, he had three sets of glasses made before he achieved an acceptable fit. Deciding this would be cost prohibitive, I used 1/8” thick, impact resistant, clear, polycarbonate plastic (Lexan) with a scratch resistant coating that is currently being used for motorcycle windscreens. It is flexible enough to bend in place without heat (with a lot of effort!) with the required bend radius being well within the manufacturer’s specification. Horn Button The amp hour meter is shown in the photo the right. It is the only instrument used to check the status of the electrical systems and is mounted on the dashboard directly across from the driver mechanism. Since everything seemed to be in good working order I oiled the moving parts, painted the cover, and mounted the meter back on the car. This is where my experience restoring antique clocks came in handy. continued on next page Amp Hour Meter restoration Below is a photo of the finished product. The only way you can tell it is plastic is by tapping on the window. The process started by cutting the Lexan to the inside shape of the window frame. New rubber trim was then cut and applied along its edges (photo on right top), and the corners glued together (photo on right below). Securing one end of the Lexan under a piece of the aluminum trim that was nailed in place (photo on right below), the plastic was forced into position by hand until a large C clamp could be applied (photo on left below). continued on page 30 September 2014 / Current EVents 29 restoration Detroit Continued from page 29 Two more C clamps forced the rest of the window into place (photo on top below). A second piece of the original aluminum molding was then slid into position in a channel behind the wooden blocks, and finally nailed to the body’s wooden frame (photo on bottom below). The clamps were then removed and the remaining top and bottom pieces of aluminum trim were nailed in place. It took two people about three hours to install one window. finding a replacement material that was wide enough to cover the top without any seams. I finally located a suitable vinyl covered canvas top material. New padding was installed and the fabric was then tacked in place. Finally, the original aluminum trim was reinstalled. Below is a photo of the finished top. The next two photos show the fabric being stretched over the padding (photo on left) and then thumb tacked in place (photo on right). The next two photos show the top material being permanently tacked in place with carpet tacks, and then cut to size. Finally, the photo below on the left shows the original aluminum trim being reinstalled along with the salvaged aluminum gutters above the doors. The photo to the right shows the completed top. #8 – THE TOP The original top was canvas coated with a rubberized waterproofing. Unfortunately it needed to be replaced as it was torn, and the rubberized coating was severely cracked making it no longer water proof. I had some difficulty 30 Current EVents / September 2014 continued on next page restoration #9 – IDENTIFICATION PLATES Other details needing attention were the missing serial number Directly below is the new door sill plate mounted in position. plate (VIN plate), the motor ID plate, and the hubcap inserts with the Detroit logo. Also, the plates on the door sills were badly worn with the one on the passenger’s side completely illegible. Each of these was carefully reproduced. Original examples of the plates were located and photos taken. Digital artwork was then meticulously created on a computer by my wife Sarah Stanley duplicating the exact images of the originals. Film positives were made, and a vendor found that could acid etch the images into brass and aluminum plates. Immediately below is the new hubcap insert, and below that is the motor ID plate. #10 – WHEELS The car had last been painted in the 1950s and was now due to be repainted. I wasn’t sure how far I wanted to take this, but I decided to start with the wire wheels as rust was starting to come through the paint and the wheels were in too good a condition to let them deteriorate further. I was advised the best and most economical way to “paint” these would be to powder coat them. Indeed for a few hundred dollars all four wheels were completely sand blasted free of all old paint, and powder coated. Directly below is the before picture and below that the after picture. They turned out beautifully, actually much better than I had expected, and so set the standard for the rest of the car. Before Powder Coating Below is the new serial number or VIN plate mounted on the heel board below the driver’s seat. After Powder Coating continued on page 32 September 2014 / Current EVents 31 restoration Detroit Continued from page 31 The next challenge was to mount the new tires without scratching the powder coating. Instead of tire irons, I used several large C clamps and a weighted rubber mallet which worked quite well. The photo immediately below shows a tire being urged in place with the C clamps. The picture on the bottom shows the finished wheels ready to be mounted on the car. This was difficult as the shape of the wood determines the contour of the lid. This has to match the curve of the body perfectly so there wouldn’t be any large gaps between the lid and the body when the lid was closed. After mounting the lid back on the car, I was very pleased as the gap turned out to be a 1/32” or less. The following two photos show the poor condition of the wood in rear lid. “Acid Rot” On Rear Battery Compartment Lid Wood The next two photos illustrate the fabrication (left photo), and installation (right photo) of the new wood. In addition to the “acid rot” on the battery compartment floors, and on the rear lid wood, there were several additional pieces of wood in both the front battery compartment (left photo below) and rear battery compartment (right photo below) that suffered the same fate and had to be replaced. #11 – THE BODY The Detroit body was handmade having a wooden frame (Ash and/or Oak) covered by sheet aluminum in some places, and sheet steel in others. On my car there was virtually no wood rot due to water damage. This testifies to the good care this car had received over the past 93 years. However, there was a significant amount of wood damage in the both battery compartments due to acid spills and fumes over the years. In particular, the frame for the rear battery compartment lid needed about half its wood replaced. 32 Current EVents / September 2014 Rear Battery Compartment Front Battery Compartment restoration As mentioned, the body is made primarily from sheet aluminum and steel nailed over a wooden frame. The exception is the framework around all the windows which for some reason was left in oak. To prepare this wood for the painter, I stripped away all of the paint with paint remover, and coated it with a penetrating two part epoxy. This epoxy is commonly used in wooden boat construction to protect wooden hulls before painting. It soaks into the wood and after hardening makes it almost impervious to water. It is also remains somewhat flexible so it can move with the wood as it expands and contracts with changes in temperature and humidity. Without this sealer, normal paint and primer could eventually crack allowing water into the wood where it could dislodge and flake the paint. The photo below shows the wood after being treated with the epoxy. Epoxy Coated Wood #12 – THE PAINTING The final painting was done by Lance Tegeder of Exceptional Finishes in Perkasie, PA. The body was stripped to the bare metal before new primer and paint were applied. Most of the body was in very good condition with only two small places where mice had gotten into the body and left their deposits which ate through the aluminum. These were cut out and aluminum patches welded in place. The fenders were the greatest challenge as they were also made of aluminum and being soft became rather “lumpy” over the years. Lance was able to save them and today they look like new. It took Lance nine months to complete the painting of the car. In the photo to the right, Lance and my wife Sarah discuss the Detroit’s progress. The final touch was the pinstriping. It was done by DeWayne Connots of DOA Flatliners from North Wales, PA. To stripe the entire car took about four hours. continued on page 34 September 2014 / Current EVents 33 restoration Detroit Continued from page 33 In the two photos below, DeWayne is at work in Lance Tegeder’s paint shop. DeWayne Connots Pinstriping The Car 13 – THE FINALE Of course, the above are only highlights of the Detroit’s restoration. It would be impossible to describe everything that was done. Suffice it to say that the first ride in the Detroit made it all seem worthwhile. In the photo below, the author takes a moment to wave hello from the Detroit’s cockpit sometime during its three year restoration. The Author, Donald R. Davidson, Waves Hello During The Restoration At the top of the next page is a glimpse of how 100 years of continual technological improvements are showcased in a modern plugin car, such as the BMW i3. That new product offers the best of today’s ICE tech to drive a electric generator (in the REX) to circumvent the shortfalls of either ICE or BEV technology in this car. Consider where we’ve come from, with this list of the strong points in modern cars. They: • have a much lower center of gravity than this tall carriage, • include effective heating /cooling systems to maximize passenger comfort, • their inside and outside lighting makes it easy to see and be seen, • are easy to handle and use in urban environments, • present no difficulties to maintain them in good and proper operation, • run cleanly and quietly, • have refined shock absorbers and a suspension which 34 Current EVents / September 2014 is the key to their smoothness, have an ability to hit and maintain high speeds for sustained freeway travel over long distances, all in comfort, with safety. These items are all the result of numerous incremental improvements made over the past nine decades in automobile models delivered by many different OEMs. We’ve seen tremendous changes in styling and capability, just incredible refinement. Now to be able to lessen our dependence on oil in the automotive sector by using electricity is a disruptive, yet sustainable step which society needs to take. The differences here couldn’t be more stark and satisfying. • Of course, the EAA gives a solid plug for the stupendous restoration and documentation effort portrayed in this article. It is clearly a very well executed, top tier job. Congratulations to Donald Davidson! restoration Photos and comments on this page are courtesy of Chris Neff. What is so amazing about Don and his wife Sarah (Sarah Stanley, great-granddaughter of Francis E. Stanley*) is that they drive their Detroit Electric today. In fact, just the other week they met up with me at ‘Cars and Croissants’ in Chatham NJ. I was able to take some pictures of my BMW i3 next to their Detroit Electric... how cool is that?? Talk about the past meeting the future. *In case you do not know who Francis E Stanley is.... co-founder, along with his twin brother Freelan Oscar Stanley, of the Stanley Motor Carriage Company which built the Stanley Steamer. They not only built the cars but they are the inventors of the Stanley Steamer. http://www. stanleysteamers.com/ September 2014 / Current EVents 35