Another window question

[Wrecit]

I looked over the pages on the other window thread started in 2019 and there is alot of good information there. For example my initial plan was to cut the ribs out weld a horizontal support in with an over sized hole then make a full plywood frame for my windows. After reading I am changing to install my horizontal tight to the frame of the window. I want to make my 6x12 build bright and ariy so I went to a local RV junk yard and picked up 2 tinted 48x20 windows (one an emergency escape window)for $80 a piece. Holding one up to the side of the trailer I am loving the look but I am starting to have second thoughts because I will have to cut out 3 ribs. As a carpenter I know larger spans are easy you just put in a larger header. This is a 1985 all steel construction Hallmark. Do you think I should beef up the main steel top horizontal to be safe or should the existing c chanel be good enough? The ribs I will be cutting will be the rear most 3 ribs. The construction of the trailer has the top c chanel welded to a 1/4 round beam that goes from floor to ceiling.

Also a side question. Everyone in the videos seems to grab a sawzall or saber saw to cut out the openings. My plan is to use a trim router and a flush bit to get my opening cut. I am reskining my trailer with fiberglass but though the bit would be junk after cutting your windows out this kind of bit should give a good tight cut even with thin aluminum skin.

Experts, your thoughts.

[tony.latham]

My plan is to use a trim router and a flush bit to get my opening cut.

Attempting to free-hand with a router is probably a road to disaster. You need a template with a top-bearing bit.





Tony

[Wrecit]

I am good but not that good lol. I was thinking this bit and using my framing as the guide

https://www.lowes.com/pd/Bosch-Carbide- ... it/1081307

[tony.latham]

I am good but not that good lol. I was thinking this bit and using my framing as the guide

https://www.lowes.com/pd/Bosch-Carbide- ... it/1081307

Gotcha. In my photo, I'm using a top-bearing flush-trim bit.

Tony

[Wrecit]

As a full time construction carpenter who does a bit of drywall I am use to using a rotozip/drywall router to cut all my openings. In theroy you may be able to use a rotozip or a trim router like I am suggesting as long as your interior window framing is exact and you make your corner radius out of plywood. The plastic corners look nice and easy but trained professionals will blow thru an electric box some times with a rotozip which are much stronger plastic so I would not suggest trying this if you use plastic corners