Installing brand new door plastic panel- drilling holes

[0TreeLemur]

As part of our interior rehab we got a new cabin door plastic panel from planeplastics.  The old one was shot.

Does anyone have a clever way to mark the spots to drill holes in the new panel to match the screw holes in the door?   There's got to be some way to do that it seems. 

Or, should we just drill new ones and eliminate the chance of a screw up?

[RLCarter]

17 minutes ago, 0TreeLemur said:

As part of our interior rehab we got a new cabin door plastic panel from planeplastics.  The old one was shot.

Does anyone have a clever way to mark the spots to drill holes in the new panel to match the screw holes in the door?   There's got to be some way to do that it seems. 

Or, should we just drill new ones and eliminate the chance of a screw up?

drill new ones and eliminate the chance of a screw up, is what I would do

[carusoam]

Somewhere is a thread...

1) a silly putty type material on the back of the panel... squished in, forms a mirror image of where the hole lands...

2) a tool that mounts in the hole and scratches a mark where the hole belongs...

Fuzzy partial memory...

Good luck with the search...

Best regards,

-a-

[milotron]

I tried to be fancy by transcribing the holes and failed. Gave up and just drilled new holes.

[0TreeLemur]

22 minutes ago, carusoam said:

Somewhere is a thread...

1) a silly putty type material on the back of the panel... squished in, forms a mirror image of where the hole lands...

2) a tool that mounts in the hole and scratches a mark where the hole belongs...

Fuzzy partial memory...

Good luck with the search...

Best regards,

-a-

Thanks -a-.   I have used 2) for woodworking/locating dowel holes.   I hadn't thought of 1)- strip mastic being useful for this.   But there are an awful lot of holes...   I'll dig.  But, drilling new holes would be easy, and lighten the aircraft some more

[DonMuncy]

Have you thought about gluing "super Velcro" like material on both the panel and the structure. I have no idea whether this is viable, but would like to know if it would work.

[Immelman]

This is a little bit of a hijack, but...

I replaced this panel. I could have done a better job on the screw holes. But there is one additional complication to think about. The new panel did not conform well to the door frame where the screw holes were.

Some years after I installed the new panel, I spoke with the (professional) interior guy who was rebuilding my seats and he mentioned they use heat to help bend these panels. I did not try that and it seems like a steep learning curve.... but learn from my mistake: Take a close look at how the plastic lays on the frame before committing to your holes. Mine isn't terrible... but it could be better.

Edited October 18, 2019 by Immelman

[0TreeLemur]

Thanks @Immelman, I'll be sure to take the heat gun with me.

[nebhuskr123]

I did this to my C about a year ago... it was a little more involved than expected. It took a lot of shaping to get the door to fit just right. Then I used these hole finders and drilled new holes. 

 

https://www.northerntool.com/shop/tools/product_200449272_200449272?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Air Tools %2B Compressors > Air Tools %2B Accessories > Air Punch %2B Rivet Tools&utm_campaign=Air Capital&utm_content=301102&gclid=CjwKCAjwxaXtBRBbEiwAPqPxcKuw4qBcts0LIoxdKxAOVi7PUm58rr-nh7eE7I8tBUI7niQ_IhkJvhoCl1EQAvD_BwE

[CaptRJM]

I just laid the old panel inside the new one and marked the fore/aft position of the holes .... then I allowed for the right/left offset caused by having them inside each other and drilled away.  Worked fine ... I don't remember having any holes that required elongation.

[Planegary]

I just located 1 hole carefully and then put painters tape around the perimeter then marked holes and then moved the tape to locate the holes to the new plastic

[CaptRJM]

The painters tape trick is what I used for the seat bottom panel as I have the fold down rear seats. Worked great. 

Edited October 20, 2019 by CaptRJM
Typo

[milotron]

On 10/18/2019 at 5:05 AM, 0TreeLemur said:

Thanks @Immelman, I'll be sure to take the heat gun with me.

Since we are all sharing...I found the plane plastics door panel much thicker than the original which affected how it fit on the edges that have the return on them. I ended up trimming most of the return away to get it to fit. In hind sight, the heat gun may have helped that, but it still would have been quite a stretch due to the amount of material there  

Be very careful with the tiny screw in the center of the lower panel, that ends up behind the upper panel. A previous owner of my plane put that one in too far and made a pimple on the outside of the door. I did not put it back in as it was not needed, nor worth the risk. It already was less than 3/16 of an inch long, not sure how much shorter they make those little #4 screws. 

[0TreeLemur]

Installed it yesterday.   The plane plastics door was not only thicker as @milotron said, the depth dimension of the plastic parts (out of the plane of the door) was elongated for the one that I got.  I wound up trimming 1/4" to 3/8" off the entire perimeter of the door.   That trim resulted in reducing the distance from the door edge to the the old holes, close enough (1/4" or so) that I could lift the edge of the new panel enough to see them and drill accordingly.

The only wrinkle was this.   After I trimmed the perimeter, the interior edges of the door panel where also extended so that at the bottom of the window the panel at the edge was about 1/2" off the door, while at the top of the window the displacement was about 1/4".   So I marked the interior edges to cut of 1/2" from the bottom of the window and 1/4" from the top, with linear interpolation between on the sides.   That end result was too much material removed .   I'm not gonna buy a new door panel.

Now I've created a challenging trim problem to solve.  I've got a 1/4" to 3/8" gap along the bottom of the window and 1/8" gap along the top.   So, it seems like  a good rule of thumb is this: if the central portion is holding the panel off by N/8", then cut N/16" off and try that.   Grrrrr.

 

[Marauder]

11 minutes ago, 0TreeLemur said:

Installed it yesterday.   The plane plastics door was not only thicker as @milotron said, the depth dimension of the plastic parts (out of the plane of the door) was elongated for the one that I got.  I wound up trimming 1/4" to 3/8" off the entire perimeter of the door.   That trim resulted in reducing the distance from the door edge to the the old holes, close enough (1/4" or so) that I could lift the edge of the new panel enough to see them and drill accordingly.

The only wrinkle was this.   After I trimmed the perimeter, the interior edges of the door panel where also extended so that at the bottom of the window the panel at the edge was about 1/2" off the door, while at the top of the window the displacement was about 1/4".   So I marked the interior edges to cut of 1/2" from the bottom of the window and 1/4" from the top, with linear interpolation between on the sides.   That end result was too much material removed .   I'm not gonna buy a new door panel.

Now I've created a challenging trim problem to solve.  I've got a 1/4" to 3/8" gap along the bottom of the window and 1/8" gap along the top.   So, it seems like  a good rule of thumb is this: if the central portion is holding the panel off by N/8", then cut N/16" off and try that.   Grrrrr.

 

I remember reading or hearing that Plane Plastics made molds by using original parts instead of using the original molds. This will make the part slightly larger than the originals. As well, they don't typically do all of the cut-outs found on the original. This results in a lot more trimming and fitting. A buddy here replaced the top half of his door. It took him hours to get a decent fit.

[DonMuncy]

1 hour ago, 0TreeLemur said:

Installed it yesterday.   The plane plastics door was not only thicker as @milotron said, the depth dimension of the plastic parts (out of the plane of the door) was elongated for the one that I got.  I wound up trimming 1/4" to 3/8" off the entire perimeter of the door.   That trim resulted in reducing the distance from the door edge to the the old holes, close enough (1/4" or so) that I could lift the edge of the new panel enough to see them and drill accordingly.

The only wrinkle was this.   After I trimmed the perimeter, the interior edges of the door panel where also extended so that at the bottom of the window the panel at the edge was about 1/2" off the door, while at the top of the window the displacement was about 1/4".   So I marked the interior edges to cut of 1/2" from the bottom of the window and 1/4" from the top, with linear interpolation between on the sides.   That end result was too much material removed .   I'm not gonna buy a new door panel.

Now I've created a challenging trim problem to solve.  I've got a 1/4" to 3/8" gap along the bottom of the window and 1/8" gap along the top.   So, it seems like  a good rule of thumb is this: if the central portion is holding the panel off by N/8", then cut N/16" off and try that.   Grrrrr.

 

They (someone) makes trim material the goes over the edge of the plastic panels. It occupies about 1/8 inch past the edge. You might check to see if it would help.

[Andy95W]

10 hours ago, DonMuncy said:

They (someone) makes trim material the goes over the edge of the plastic panels. It occupies about 1/8 inch past the edge. You might check to see if it would help.

Bruce Jaeger can get it or knows where it comes from.  It's a silicone product that gets glued on with clear RTV.  I've only ever seen it in light beige, other colors may be available. 

[DonMuncy]

6 minutes ago, Andy95W said:

Bruce Jaeger can get it or knows where it comes from.  It's a silicone product that gets glued on with clear RTV.  I've only ever seen it in light beige, other colors may be available. 

I got some that doesn't glue on. It slips on the edge and stays on by friction.

[milotron]

I got that stuff from plane plastics I belIeve. Slips on. The stuff I had before was rock hard and shattered when moved. 

[RLCarter]

I think you guys are talking about pinch molding

[M20F-1968]

Locate the holes by using machinist's hole finder pins.  They can be purchased or made yourself given that you only need a low level of precision (as opposed to +/- 0.001" that a machinist may require).  They are essentially a machine screw (or in this case a sheet metal screw) with the head removed, leaving a threaded shaft, one end of which is ground to a point.  Install the threaded shaft into the hole in the aircraft with the pointed end facing toward the plastic to be installed.  Screw them into the aircraft so they stick out about the right amount as needed for the finish installation (so everything is where it would normally be when installed) and hit the plastic with a rubber mallet or similar device to mark the backside of the plastic.  Then, drill your holes.

John Breda

[Mooney1]

20 hours ago, Marauder said:

I remember reading or hearing that Plane Plastics made molds by using original parts instead of using the original molds. This will make the part slightly larger than the originals. As well, they don't typically do all of the cut-outs found on the original. This results in a lot more trimming and fitting. A buddy here replaced the top half of his door. It took him hours to get a decent fit.

I used a Plane Plastics kit to restore a 152 a few years ago and found the pieces fit really well with minor trimming. I guess YMMV

[Marauder]

3 hours ago, Mooney1 said:

I used a Plane Plastics kit to restore a 152 a few years ago and found the pieces fit really well with minor trimming. I guess YMMV

It might be they actually have the original molds for the Cessna series. Could also be that Cessna used a really thin Royalite that if they created a copy of a copy, the extra thickness didn't make a difference. My experience with the Mooney stuff is that it requires a bit more work to get it to fit correctly.

[Hank]

7 hours ago, M20F-1968 said:

Locate the holes by using machinist's hole finder pins.  They can be purchased or made yourself given that you only need a low level of precision (as opposed to +/- 0.001" that a machinist may require).  They are essentially a machine screw (or in this case a sheet metal screw) with the head removed, leaving a threaded shaft, one end of which is ground to a point.  Install the threaded shaft into the hole in the aircraft with the pointed end facing toward the plastic to be installed.  Screw them into the aircraft so they stick out about the right amount as needed for the finish installation (so everything is where it would normally be when installed) and hit the plastic with a rubber mallet or similar device to mark the backside of the plastic.  Then, drill your holes.

John Breda

As an engineer and machinist, I have this type of trouble frequently when doing woodwork in my basement . . . . . Lumber, like vacuum formed plastic parts, isn't available to thousandths of an inch tolerances.

[drapo]

Originally, I wanted to repair the plastic door panel, but after a few tries, I decided to go for a new panel. This was the old one, cracked up at all the wrong places...

So I bought a new panel and we did a lot of trimming to make it fit. Some areas were problematic, like the upper right side, the extra material would interfere and not permit to achieve a tight closure. To match the holes, we used screw that we decapitated, screwed into existing holes and applied pressure. Decided to use larger screws and put less of them and I prefer that less cluttered look. We'll finish it with silicone after the winter season.