Door Poppers

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Major System Category: Body (Door)
Task: Install door poppers
Parts: Popper solenoid, cable, pulley
Prerequisite Tasks:
Additional Costs: $75
Time Requirement: 4 hours
Date Started: November 21, 2012
Date Completed:  November 25, 2012

One of the issues I worry about is security. These cars attract a lot of attention. Chances are people have never seen a GTM.  I decided to go keyless early in the planning stage. This means the normal form of ingress (i.e. door handles) needed to go away. I'm not going to go into detail on the security system, except to say it is multi-layered and bio-metrically keyed to me. Yes, if I have a dead battery, she's going to be hard to start.

These are the pulleys and the solenoid base plate.

The first security layer is to eliminate door handles and rely on door poppers to open the door. There is a need for a manual override, and I have something in mind for how I am going to put that together. To operate the poppers I have a fob. The fob is linked to the RFlink module installed in the ISIS master cell. However, the fob can only get you into the car. It has nothing to do with starting the car.

The rear of the solenoid where I attached power and ground leads. This is clamped in a vice. I did  all the electrical work down stairs in my cave, as the temperature was dropping through out December.

I am using 60 lbs solenoid door poppers and a plungers to push the door open past the striker. The plungers (like the striker) need to be installed after the engine and transaxle are installed. The plungers need to be secured against the chassis and installed through the body shell.

The solenoid popper is bolted to the mounting bracket. The steel cable is looped around the end of the solenoid and the clamp is in place, but not compressed. Yes, they don't make vices like this any more. It was purchased 60 or 70 years ago.

The latch has a vertical orientation. The idea behind the popper is a solenoid attached to a wire cable that fires (i.e. contracts) been an electrical charge is applied. Unlike the rear hatch popper, it is not possible to position the solenoid so it is in a straight line to the latch.

Close up of the pulley with the steel cable threaded. At this point nothing had been tightened down, so that is why there is slack on the line. The pulley is riveted into place. You can also see the narrow end of the internal brace. Things are very tight on the rear edge of the door.

The solenoid works on a electrical charge that fires the solenoid causing it to contract into the housing. I attached five feet of 16 gauge wire for power and ground. This has to be threaded out of the door and into the front hood area where it gets connected to the power cell and grounded at a ground point on the chassis.

The popper solenoid and pulley before the steel cable is tightened into place. The cables from the window motor is just to the right of the popper solenoid and the black bracket in the middle of the photo (behind the brace) is the window track.

I use a 12 volt test battery to verify the connections are working and that they are solid (this is a lot of fun - it's a guy thing). The solenoids come with a heavy bracket. This is mounted to the bottom of the inside of the door. I used short bolts and nylon nuts to secure it in place. The last thing I want is for the popper solenoid to slide loose inside the door.

Everything is tightened up. Note: There is still some slack in the steel cable.

The idea to use a pulley and form a right angle between the latch and the popper solenoid is not original with me. I don't remember where I first saw the idea, but it really works. The pulleys are quite simple (a $2 part at Lowes). I think I found them in the screen door section. The pulley allows me to create a right angle between the popper solenoid and the latch. I riveted the pulley into place and checked for strength.

I threaded the steel cable from the latch, through the pulley and to the popper solenoid. The cable loops around the solenoid end and is crimped using the two channel clamp. If you lose one of these clamps, there are available at the little parts area where they sell pulleys at Lowes and Home Depot.

Once everything is tightened down, I retrieve my test battery and fire the solenoid. There is plenty to check:

1. The door latch actually opens.
2. The pulley doesn't stress.
3. The bracket holding to solenoid doesn't stress.

I fired the solenoid about twenty times. There is a significant bang each time. 

Door Latch

<< Power Window Motor and Track            Door Popper >>

Major System Category: Body (Door)
Task: Install door latch
Parts: Door latch
Prerequisite Tasks:
Additional Costs:
Time Requirement: 4 hours
Date Started: November 19, 2012
Date Completed:  November 19, 2012

Originally, I had the door latch and striker as part of the same task (i.e. the latch closes around the striker and that's what keeps the door closed). I started working on the doors prior to putting an engine and transaxle in the car. The only way to get the engine and transaxle into the car is to remove the body shell. This is already complicated by the rear hatch hinges and the front hood latches. Both of these have to be disconnected before the body shell can be removed. Installing the striker, adds a needless complication to the removal process. So this part will have to wait until after the engine and transaxle are installed (sometime in 2014).

This is the latch attached to the mounting bracket. Factory Five purchased the latch from a third party. I am pretty sure they machined the mounting bracket.

Likewise the doors have to be removed from the car before the shell can come off. The doors seem less problematic that the hatch hinge and hood latches, because by the time I have to remove the doors - everything related to their fitment should be in place per the arrangement of the hinges on the doors.

The curved part is the cut out area where the latch is exposed as part of the door. 

The latch has a similar arrangement in terms of adjustment as the hinge does. The work area for the latch is very tight, and difficult to work with. The hinge and the latch need to be tightened down together. This happens prior to window placement, since the internal frame needs to be solid so the window tracks can be attached. There are a bunch of pieces here and they all have to work together.

This is the latch mounting bracket connected to the internal frame on the rear side of the door. To the right of the internal frame, the opening for the external door handle is in close proximity to the latch controls. This will be covered up and closed in as I am opting for shaved door handles and internal door poppers.

Placement of the latch is dictated by the formed cut out area for the latch and the depth of the latch inside the door. In other words, enough of the latch needs to be visible so the striker can properly mate with the latch. I already have some issues with the drivers side hood latch and I don't want to repeat that mistake here. Eventually, I am going to have to adjust the hood striker to line up a little better, but I am holding off until the body shell goes back on for good (i.e. after the engine and transaxle are installed).

This photo shows the internal frame connected tot he latched, the rear window track and the  cables going back to the motor, and the internal door popper. The items still missing at this point is the glass, the fixed tracks, the filled in exterior door handle (i.e. shave door handle), and the internal mechanism to open the door from the inside of the car.

I used the Dremel with a cut off wheel to cut the fiber glass and open up a slot for the latch mechanism. The fiber  glass is very thin here as it is on the hinge side. Once I had the latch comfortably exposed, I tested the latch mechanism by pushing the striker into place.

Power Window Motor and Tracks

<< Door Hinge                                             Door Latch >>

Major System Category: Body (Door)
Task: Install power window motor
Parts: Power window motor and tracks
Prerequisite Tasks:
Additional Costs:
Time Requirement: 4 hours
Date Started: November 19, 2012
Date Completed:  November 19, 2012

There is a right and a left side power window motor and window track. The easiest way to figure this out is to read the labels. At least, one label should still be present. After you figure out the drivers and passenger side motors out, the next challenger is to figure out which end is up on the window tracks. I'm sure this is obvious to some people, but it was a mystery to me.

This is the power window motor. Attached by cable are the window tracks. It  has the form of a floppy hour glass shape. I would check the pulleys where cable runs to make sure they are secure and not chipped. I think that last thing anyone wants to do is to back in here to fix something like that.

The manual says there are two bolts that need to be removed from the top end of tracks. The suggested method is to pound out the bolt by placing it over a socket. The bolts on my tracks were frozen in pace, I and was concerned that pounding on the track might deform something. So I used a cutting wheel and drill to remove the bolts. I've since purchased a Drill Doctor, because cutting out harden bolts has done a real number on many of my bits.

The kit includes brackets to attach the window tracks to the internal frame. I've held off on this until I get a sense for how the window is going to interact with the rest of the door. I have read numerous build logs where the windows refuse to go down all the way. This indeed may happen to me, but I'm going to make a good faith effort to get the window to go all the way down into the door.

The final thing that needs to be done is to re-position one of the cables running out of the motor. What you will notice is that once the motor is attached to the frame the cable going towards the rear window track is awkward. I don't think this is in the manual, so I read it on a build log (I apologize because I don't remember which one it is.). There are five big screws that hold the plate in place for the cables. These screws and plate need to be removed and correct cable needs to be moved one channel upwards. The cable is still going to be tight, but it is workable.

This is the window motor cable system with the plate removed. the cable with the green tab needs to be moved to the next channel. This is a tad intimidating the first time through, because I figured I might really mess things up. If you take your time, it is fairly bullet proof.

The photos in the manual are pretty good about how to attached the motor to the "C" shaped fitting on the brace. The main consideration is leaving space for the glass to descend (width wise). I have approximately 1/2 inch left for the glass to move up and down between the motor and the inside of the door. It seems there is more room on the drivers side door than the passenger side door. Again, it does not appear that doors are symmetrical.

Thie window motor is attached to the internal brace. Note the access plate for the cables faces the sound proofed panel. These screws line up with the brace. Again this is fairly straight forward. What is awkward is the uncertainty of how this all going to work properly. I suspect that the window tracks in the GTM are at much tighter angle than they are inside the Corvette door they came from. I haven't dismantled my Corvette door to find out. I'm not that curious! You can also see the power connect (orange tape) on top of the brace.

The power connector to the motor can be removed. This makes it easier to attach a ground and positive wire to the leads. (Remember, there has to be power to the motor, mirrors and door poppers. This is a good time to get the electrical work down. The wires feed out through an opening cut above the top hinge. Once I have things set, I and going to reinforce the area between the bottom of the power line opening and the top of the hinge slot. The fiber glass is real thin here. I used my 12 volt test battery to check the motor and the tracks. They move real good without any glass installed.

Door Hinge

<< Preliminary Fit                         Power Window Motor and Tracks >>

Major System Category: Body (Door)
Task: Door hinge
Parts: Door hinge and internal frame
Prerequisite Tasks:
Additional Costs:
Time Requirement: 5 - 6 hours
Date Started: November 11, 2012
Date Completed:  November 14, 2012
The door hinge, the internal frame, power window motor, window tracks and the latch really need to be part of the same discussion. If you just install the hinge without thinking about everything else, then you are going to end up taking everything apart and redoing things anyway. the latch and hinge are on opposite sides of the internal frame. The power window motor and window tracks  happen before and after this section.

Front trim panel for driver's side door. I found it useful to have a table next to the lift  as a work area.

I am going to break things down into multiple sections. The major consideration here is that each of these systems have to worked together. This is what makes the door construction a pain. Unlike so many other things, where you can focus on one item, you will need to keep all of these items in mind as you build the doors:

1. Hinge
2. Power window motor and tracks (not attached)
3. Latch
4. Door poppers (optional component)
5. Shaved Handles (optional component)
6. Side mirrors

Hinge plate set in place so I could get a preliminary placement prior to cutting holes. I added sound proofing to the interior of the door. I would strongly recommend this as the doors seem kind of thin.

The manual makes this entire process sound like a pleasant walk in the park. While there is nothing overly complicated, there is lots of adjustment. Let me repeat that: THERE IS LOTS OF ADJUSTMENT.

The hinge and trim plate set in place on the door. Everything seemed so simple at this point. However, I have read enough on other builder blogs to know this is anything but simple.

The first thing I notice is that the manual makes everything look very simple to fit together. It does fit together, but not easily. If you follow the instructions and measurements, you will be off to a good start.

This is a close up of the hinge plate and the internal frame as they fit inside the door. They are not  bolted together yet. The black metal piece is the window track.

The front door trim panels are smaller than they look in the manual. it is easy to miss them in the sheet metal box. I found a Dremel tool with stiffer cut off wheel to useful in cutting the openings for the hinge plate. Burrs and jagged edges can be smoothed out using a sanding drum. Anything bigger is going to get in the way. These doors are not that large, and it seems they get smaller as systems get installed.

This is a photo much further along in the process for the door build. It shows the  hinge plate and internal frame bolted together. Some of the electrical work is complete and those cables snake out through the opening above the hinge plate.

There are two sets of bolts to work with. The first set connects the hinge plate to the internal frame. (Keep the socket wrench handy, you are going to need it to move things around.) the second set of bolts connect the front of the hinge through the square holes for the trim plate. There is a certain amount of adjustment room for these connections. However, these adjustments become more limited when the latch is attached on the other end of the internal frame.

Preliminary Fit

<< Initial measurement and Mounting                        Door Hinge >>

Major System Category: Body (Door)
Task: Test fit the door
Parts: Door
Prerequisite Tasks:
Additional Costs:
Time Requirement: 3 hours
Date Started: November 08, 2012
Date Completed:  November 10, 2012

There is a lot of things happening with doors. There are multiple systems (both mechanical and power) taking place in the door. The doors are fairly light (prior to installing all the hardware), so they are easy to move around to get an idea of how the doors fit on the car,

This is GTM #402 coming off the truck. You can see the tape along the door edges holding the door in place. When this happens, the leading edge of the door (inside the front cove of the body shell) is right up against the hinges that are part of the chassis. There is no way the hinges installed on the door can be that close.

When the car arrives, the doors are taped in place. This is deceptive. When the car is shipped the doors are pushed past the hinge points on the chassis. This makes it seem like the doors are already fitted in place. Reality is much different. The rear edge of the door is over sized and needs to be trimmed.

This is second photo of the tape used to hold the doors on for shipping.  When actually fitting takes place, some material will need to be sanded off the rear edge of the door.

Note: Hold off trimming any part of the door until the hinge is installed on the door and you have preliminary mount on the chassis.

The hinges attached to the chassis right above the puppy's head.

The other item I anticipated was that the upper and lower hinges for the door match the alignment of the hinges on the chassis. When the door hinges are properly aligned, the lower hinge is canted further away from the door than the upper. This allows the bottom of the door to be canted at angle closer to the body shell. I didn't understand this right away and ended up with an initial fit running a huge gap along the bottom of the door.

These are chassis hinges with the body shell installed. The door hinge fits on top of these hinges and you drive a hinge pin through. The chassis hinges are in vertical alignment. This is much different from the Corvette door set up, where there is much more room to work and the hinge pieces are much easier to access. This really is a two person job. Or a one person job with a little bit of luck.

Note: The lower hinge mounts closer to the chassis than the upper hinge. This supports way the door rests inside the body shell (i.e. the lower part of the door angles outwards and upwards to the top of the door).

Close up of the bushing. These are made of brass or some similar soft metal.  They will  rip apart  on you if you don't get the door in place just right. Fortunately, you can order extras from Amazon.

I managed to wreck a pair of hinge bushings. The Dorman 38377 part is a suitable replacement for these bushings.