The International Cessna^® 170 Association

I have a '56 C172 with a fixed window on the passenger side door. I want to replace the side window and it appears that I have to drill the rivets and split the door to do the job. I looked in the maintenance manual which didn't give any specifics about fixed window replacement. I just joined the site (minutes ago) and haven't been upgraded to member status. I have searched the portion of the site I have access to, looking for information/procedures but haven't found anything.

Can anyone who has done this job give me some information on the procedure and how entailed it's going to be? I have no experience bucking rivets other than seeing it done a couple of times. Since I'm guessing that I'm going to have to drill and buck a bunch of rivets, can you tell me what size/type rivets I'll need to buy? I looked in AC Spruce and it looks like they're sold by the pound. Is there a cheaper way to purchase them so I don't end up with many hundreds I won't use? I have an A&P who will oversee the work but want to have as much information as possible before I speak with him about doing the job.

I'm going to do the pilot side window as well which looks significantly easier since it's hinged.

Thanks.

Frank

Just found that I can buy smaller quantities of rivets from Spruce.

It is as you describe. Drill out the rivets on the bottom and slide the window out of the frame. Resecure using the rivets that are called out unless a bigger rivet is necessary to sufficiently secure the frame. It is rather easy.Leave the protective plastic on the window till your finished to reduce the chance of scratching. Also make sure you smooth all edges of the window so it will not stress crack when heating and cooling. Doug

Hi Frank,

I have to do this also on my 56. Where did you purchase the windows?

Pete

I didn't purchase windows, I purchased 2 pieces of .125 plexiglass from professional plastiscs to cut on a bansaw to make the windows. Windows are available here http://www.glapinc.com, and elsewhere. About $200 for the front two side windows from a supplier, less than $50 for the plexiglass to make two windows.

Good luck.

Frank

Doug,

Do you mean that i have to drill the rivets at the buttom and side of the door and split the door into the inner section and outer section? I have not pulled the panel on the inside of the door yet, but it looks like the door has to be completely disassembled to get the window frame out.

Thanks.

Frank

canav8 wrote:It is as you describe. Drill out the rivets on the bottom and slide the window out of the frame. Resecure using the rivets that are called out unless a bigger rivet is necessary to sufficiently secure the frame. It is rather easy.Leave the protective plastic on the window till your finished to reduce the chance of scratching. Also make sure you smooth all edges of the window so it will not stress crack when heating and cooling. Doug

Frank, you have to understand most of us don't have the same door/window on the right side as there where few '56s built. And so most of us have not had the subject door/window in hand to study.

Looking at the IPC is only a little help. But it looks like a window channel frame similar the left door window frame, is built into the door. I'd look around the top front and back around the window to see evidence of rivets or screws that hold it in. If you find such attachments, removing them might let the frame be pulled in and out from holding the window plexi up tight against the outer skin. Looks like there is a bottom channel that will hold the plexi in place while the frame is removed.

Again only a stab from looking at the IPC. I was flying in a 170 with a '56 or later door on the right last week but don't anticipate seeing it again shortly. If I do I'll look closely at it. I doubt you have to remove any part of the outer skin of the door from the inner door frame to remove the window.

Thanks Bruce. I'll figure it out and post what was required to get the window out once I do. I'll obviously welcome any experience in the mean time.

Frank

Frank, my sincere apologies. I misread your post and Bruce caught it. I thought you were talking about the window frame style and not the fixed style. Bruce is correct. looking at your IPC will yield how it goes together. The fixed window is not as easy to change and will require a little more work to replace.Thank you Bruce for catching this.

Frank,
I'm just armchair quarterbacking this like everyone else, as I don't have any experience with it. But looking at the 170B IPC FIg 34A, it looks like you would tackle it initially from the inside of the door by removing the upholstery panel (Item 4), which appears to be attached just by Auveco upholstery fasteners (Item 5). If the IPC is correct, that should give you access to the riveted horizontal channel supporting the bottom of the window. You can see that channel in the sub-figure at the top right of FIg. 34A (the channel containing the window glass seal 36). I'm guessing that if you remove the rivets securing that channel you will be able to take if off and the window will slide out downwards. Again, I'm Just guessing, but you might want to investigate this approach as well. Good luck with it.

O.K. call me slow but when I read the initial question, it would seem to me Frank needs basic sheet metal help first. Frank if I'm wrong let us know but if I'm right, first I'd give some basic advice. Your first challenge is to remove the rivets, for that matter removal of any rivet without damaging the hole. This requires good eyesight, basic hand-eye co-ordination, a drill that spins true and sharp drill bits. Some practice first then plenty of patience and you should be fine. If I'm off-base, I apologize in advance Frank but I admire good sheet metal skills and think its one of the harder skills to master.