Interior Door Panel Repair Thread

[bbade]

I began this project to clean up my window regulators in an attempt to speed them up a bit, like all projects it has grown exponentially .

I got my inspiration from this thread over on 7club.
http://www.rx7club.com/showthread.php?t=910274

There are a couple notes I would like to make:
1. When removing the passenger door panel remember to pop out the window switch and remove the philips head screw.
2. I elected not to spray silicon lubricant down the run channels as I figure over time that will just collect dust and compound the problem. I also elected not to remove the run channels so for now I have left them as is.
3. To operate the passenger window both the driver's and passenger's window switches must be hooked up.

As of now, I have only done the passenger window regulator, I expect the driver's side to be much the same.


Now, for the rest of the project! I will be addressing several issues:
1. Broken interior passenger door handle
2. Poor looking 93 plastics on both doors
3. Dirty interior door panels
4. Broken/Cracked mounting studs on door plastics
5. Stripped studs on exterior door handles

I have begun this process on the passenger side and am verifying my methods to ensure that I don't pass along any incorrect information. I will post up some details as I go and will go more in depth when I tackle the driver's side.

[bbade]

**Full-size pictures available by clicking on the thumbnails**

Repairing broken studs. Here is the culprit:
DSCF4040.jpg

You will need a nylon bushing (3/8" OD, 1/2" length, ID less than 9/32") found at your local hardware store.
OD - outer diameter
ID - inner diameter
You will also need some Plast-Aid, more about that in the next post.

Step 1: Drill the nylon bushing to 9/32" ID. This will fit nicely over the broken stud.
DSCF4041.jpg

Step 2: We want to cut two slits in the nylon bushing so that it will fit down on the stud around the four existing plastic reinforcement tabs as shown in the following picture.
DSCF4044.jpg
To do this use a dremel tool with cutoff wheel attached. Cut the slits to a depth of 1/4," this will leave 1/4" above the plastic reinforcement tabs and make it flush with the foam on the back of the door panel when finally mounted.
DSCF4043.jpg

Step 3: Enlarge the mounting hole for the stud in the door panel to 3/8" using a 3/8" drill bit.
DSCF4046.jpg

Instructions continued in the next post.

[bbade]

Step 4: Test fit the plastic piece to ensure proper fitment and alignment. Make sure that the nylon bushing is flush with the back of the door panel and make sure that the plastic piece lines up correctly.
DSCF4047.jpg
DSCF4048.jpg

Plast-Aid http://www.plast-aid.com/
Credit goes to 'nashman69g' on 7club for experimenting with this stuff, it is actually how I found it. Some great information and tips on using it can be found in this thread on 7club http://www.rx7club.com/showthread.ph...plastic+repair.
DSCF4050.jpg

Step 5: Clean the nylon bushing and broken stud with acetone. Be cautious with the acetone as it can soften/melt the plastic if left to sit on the plastic. I put some acetone on a rag and wiped everything down, allow it to evaporate.

Step 6: Put some Plast-Aid on the inside of the nylon bushing and then press it down on the broken stud. Fill the nylon bushing with Plast-Aid, bringing it level with the top of the bushing. Liberally spread Plast-Aid around the bottom of the nylon bushing (the area with the slits) to bond it with the plastic reinforcement tabs. Avoid getting Plast-Aid on the outer area of the bushing that will go through the hole in the door panel so that you don't need to trim it down later.
DSCF4052.jpg
DSCF4053.jpg

Allow the Plast-Aid to set up, it should not take long at all. The stud should now be ready to drill and tap, I will post information on this step when I get to it, I may upgrade the fasteners in the process.

[bbade]

Cracked Stud Repair:

The majority of mounting studs on my passenger side interior plastic were cracked, so to prevent them from breaking completely I reinforced them with Plast-Aid. Hopefully this will prevent further cracking, if not I will have to go back in and repair them with a nylon bushing per my last post.

The procedure is simple, clean with acetone, and spread Plast-Aid over the crack and surrounding area. The first picture shows the crack highlighted with silver sharpie. The second picture shows the stud reinforced with Plast-Aid.
DSCF4054.jpg
DSCF4055.jpg

[bbade]

Door Panel Cleaning:

Fortunately the door panels were not too dirty, but I figured I would give them a good cleaning while they are out.

We will need:
Simple Green
Bucket
Sponge
Q-Tips
Vinyl Cleaner/Protectant

Step 1: Mix up a cleaning solution in your bucket using Simple Green and some water, dilute to your liking.
DSCF4064.jpg

Step 2: Clean the panel using the sponge, use the Q-Tips for tight areas.
DSCF4065.jpg

Step 3: Rinse the panel off well using a hose, then dry it off with a soft towel.
DSCF4067.jpg

Step 4: Use a vinyl cleaner/protectant on the door panel to finish everything off and ensure that it stays nice. I used this stuff from Meguiar's.
DSCF4087.jpg

While cleaning I noticed that the ventilation duct on the back of the door would not line up correctly. I took it off and drilled some new holes to hold it in place correctly. Not sure what size bit I used, just grab one large enough for the mounting screw to fit through.
DSCF4066.jpg

[bbade]

Passenger Door Handle Repair:

Now for the infamous door handle, mine was broken by an excited passenger last summer at a track day . There are several documented fixes for this handle, but I didn't find one that quite fit my liking.

Step 1: Clean the break area. Trim back any overhanging foam tape. It is also a good idea to trim down the break so that the Plast-Aid can really penetrate and get a good bond. I didn't get a good picture of this step, but here is a picture of the break I am working with.
DSCF4057.jpg

Step 2: Attach the two broken handle pieces to the main plastic piece; there will be two screws on the upper portion and two screws on the lower portion of the handle. Once all the plastics are together, attach them to the door panel as though you were reassembling everything; there are 6 or 7 screws. I forgot to take a picture of this step, but y'all know what the door panel looks like assembled.

Step 3: Make sure all the plastic pieces are aligned satisfactorily. Then tape some aluminum foil around the back side of the break (looking at the door panel), this is to prevent Plast-Aid from leaking through. Mask off the area around the window switch hole and place a towel or rag over the door panel to serve as a drop cloth. You want to be very careful not to drip Plast-Aid on your door panel.
DSCF4070.jpg
DSCF4069.jpg

[bbade]

Step 4: Working through the window switch hole, use Plast-Aid to bond the two pieces of the handle together. There is no need to go overboard here, use just enough to securely hold the pieces together as this is just a small bond to get everything aligned correctly. Make sure to allow the Plast-Aid plenty of time to setup, I think I gave it a good 45 minutes or more to be safe.
DSCF4074.jpg
DSCF4075.jpg

Step 5: Disassemble the plastics; remove the main plastic piece from the door panel and the handle from the main plastic piece (the two handle pieces should now be a solid unit). Remember to treat the handle with care as it is only held by a small bond. You should be left with something like this.
DSCF4077.jpg

[bbade]

Step 6: We will be using a small piece of metal to reinforce the handle. I used a piece out of an old erector set as it is very strong yet still bendable.
DSCF4079.jpg

In the above picture the metal is already bent. We want to bend the metal in such a manner that it will conform to the inner contour of the handle and allow it to be attached to the main portion of the handle with a screw. When choosing and bending your metal remember to allow for the window switch, we want to make sure it will clear the metal when everything is assembled. Perhaps a picture will provide better explanation.
DSCF4080.jpg
DSCF4081.jpg

I used a basic pan head screw, 3/4" in length, but most any screw will do. You will want to drill a hole down into the handle and then thread the fastener gently by hand with a screw driver.

[bbade]

Step 7: Clean the metal and surrounding area with acetone, again be careful with the acetone as the plastic will melt with prolonged exposure. Now, pile on the Plast-Aid to really strengthen the joint and secure the metal to the handle.
DSCF4083.jpg

Step 8: To finish off the handle strengthening we want to bond the backside as well. Mask off the area around the break on the backside of the handle so that no Plast-Aid will go astray.
DSCF4084.jpg

Step 9: Clean the area well with acetone, being careful not to melt the plastic, allow the acetone to evaporate. Now bond the two halves of the handle together with the Plast-Aid. Try to lay it in there real nicely to avoid extra sanding/finishing later. Allow the Plast-Aid to set up.
DSCF4086.jpg

Step 10: Now that the handle is back together and stronger than ever it is time to finish it off, make it look nice. I have 93 plastics so the rubbery finish needed to be removed. I found the best way to do this is VERY CAREFULLY with acetone. I emphasize very carefully as the acetone will eat/melt/deform the plastic. I had to sand out a few small deformities resulting from over enthusiasm with the acetone. Work in a small area at a time, rinsing with water frequently, it will not take much to remove the finish. Once the finish is removed it is time for some sanding. I used 150 grit to smooth out the Plast-Aid bond, and attempt to match it with the handle contour. Finish with 400 and 600 grit sandpaper.
DSCF4089.jpg

Continued in next post.

[Signal 2]

Very nice. Thanks for taking the time. I've got a few of those broken studs myself. So far they haven't been an issue, but I smell a winter project.

I've never worked with the Plast-aid. In the final step or any of the steps using the Plast-aid, do you need to sand the metal and/or plastic surfaces to help adhesion?

[bbade]

Hey guys, sorry for the huge delay. I just returned from an unexpected week-long trip to Indiana. I managed to finish the passenger side prior to leaving so I will post updates asap.

Signal - I did no sanding on the plastic or metal and had no issues with adhesion, this stuff sticks! I had attempted to make a mold out of wood soaked in grease similar to something they show on the Plast-Aid website and it even stuck to that. Cleaning the bonding surfaces well with acetone should be all that you need to do to ensure a good bond; however, I would not count on it bonding with the metal, I laid down a nice thick coat encasing the metal reinforcement so I was counting on it bonding to the plastic itself.

[bbade]

Step 11: Paint! We are just about finished. Clean the handle well with soap and water to remove any sanding dust or grease. I used Duplicolor Adhesion Promoter and Duplicolor Bumper Coating (I think it comes in several colors so make sure to get black). Autozone no longer carries Duplicolor, I lucked out and got the last cans of the stuff, but I imagine it isn't that hard to find elsewhere. Follow the instructions on the can, I laid down 3 coats of adhesion promoter at 2-3 minute intervals. Wait about 10 minutes then lay down 2 coats of the bumper coating at 3-5 minute intervals. As always with spray paint, several light coats are better than one heavy coat.

DSCF4090.jpg
DSCF4095.jpg
DSCF4097.jpg

You can tell I could have laid the Plast-Aid in a little thicker in some areas, but I really wasn't concerned as this portion of the handle is not visible when the door panel is assembled. Here it is assembled, the main plastic portion has also been refinished with the bumper coating.

DSCF4099.jpg

Here is a close shot to compare the bumper coating with the 93 finish on the window switch. I elected not to refinish the window switch as I didn't want paint getting into the internals and on the contacts causing further headaches. The bumper coating has a nice texture to it, I was extremely pleased with the way it came out.

DSCF4101.jpg

[speedjunkie]

Looks great!

I just fixed all my passenger door handle problems several months ago. I don't remember having to use a metal piece to attach the bottom of the handle to the other piece though...? I think the screw was just loose or missing or something, I don't remember for sure. I'll have to look at it the next time I take it apart. It's solid as hell though. I let people actually use the handle to close the door now LOL.

I had a problem with the mounts on the long thin part too, the one holding the very back of it down, close to the striker end of the door. I didn't know you could get those nylon bushings though. I just JB welded a bolt on there because my mount was completely gone and I used a nut on it. Actually I think I used two nuts, one as a locknut, and tightened them against each other.

I also had a problem with the mount right behind the window switch. I JB welded that back together too. So far it's been holding up pretty well, knock on wood lol.

I didn't do any cleaning of window runners or regulator though, now I kinda wish I had done that while I was in there, didn't even cross my mind.

[bbade]

Okay guys, some updates will be coming next week, ran into some problems on the drivers side plastics. One stud was broken off at the base and has given me a real headache, I have gone through two attempted repairs so far and am finally going to do it the right way this time.

My first attempt was to take the broken stud and reattach it with the Plast-Aid. While attempting to glue the stud and plastic together everything shifted and would not line up correctly with the door panel. Also, I decided it was a half-assed way of doing it so on to attempt two.

Attempt two started with a nylon bushing similar to the stud repair outlined above. Everything went together without a hitch and appeared to be fine, but turns out Plast-Aid does not form a chemical bond with nylon. When I repaired the last stud I used more than enough Plast-Aid to form a mechanical bond; however, there was no way to get that much on this stud. I am not worried about the last stud I repaired coming apart because of this revelation, but I realized I needed to take a new approach.

This third fix will work as I am done playing around . I have ordered ABS rod from McMaster Carr and am going to make one heck of a robust stud. I will outline the process and post it here sometime next week.

[bbade]

Originally Posted by speedjunkie

Looks great!

I just fixed all my passenger door handle problems several months ago. I don't remember having to use a metal piece to attach the bottom of the handle to the other piece though...? I think the screw was just loose or missing or something, I don't remember for sure. I'll have to look at it the next time I take it apart. It's solid as hell though. I let people actually use the handle to close the door now LOL.

I had a problem with the mounts on the long thin part too, the one holding the very back of it down, close to the striker end of the door. I didn't know you could get those nylon bushings though. I just JB welded a bolt on there because my mount was completely gone and I used a nut on it. Actually I think I used two nuts, one as a locknut, and tightened them against each other.

I also had a problem with the mount right behind the window switch. I JB welded that back together too. So far it's been holding up pretty well, knock on wood lol.

I didn't do any cleaning of window runners or regulator though, now I kinda wish I had done that while I was in there, didn't even cross my mind.

Thanks!

The metal was not used to attach the handle to the door or plastics, it was used to reinforce the two halves of the handle itself. My handle was completely broken in two which is the only reason it was necessary to do the repair.

Good idea with the bolt; nice, simple, efficient fix. I have since discovered that Plast-Aid does not form a chemical bond with nylon which is unfortunate, but I was able to get more than enough in there on the last stud to form a mechanical bond. I am going to take a new approach when repairing the driver's side plastics.