Brackets, upholstery, and time consuming scrap aluminum

I was too tired at the end of the night last night to post, so this post covers the last two days. Yesterday, Greg was able to come and help, and he was the most productive of the two of us. He was able to get the new forward mount for the oil cooler done, and mount the oil cooler. Throughout the day, we spent some time planning the aft mount and he started fabricating that as well. The aft mount is made of a pice of thin aluminum plate that we bent to make a bracket. I cannot recall the thickness of it, but the bending actually went surprisingly well, considering we used a mallet and some aluminum bar stock as our bending die.  I forgot to get photos of this, so we will have to show it to you next work session.

The big excitement for the day was that Sean came over with “finished” seats. They look great. Unfortunately, during the course of sewing and gluing in his shop, away from the airplane, some things shifted for the back seat and a few minor details were forgotten on the front seat. Not to worry, Sean is confident with a few easy changes, he will have them ready for this coming Sunday night, when I get back. I will take some more detailed photos when they are completely done next week, but you have been waiting long enough to see. They look gorgeous.

In between working with Greg on the oil cooler mount and working with Sean on upholstery, I was working on the aft engine baffle. We previously made a template, so next was starting to cut the sheet aluminum blank. I had a roll of .025 2024, so we sheared a manageable piece from the roll and traced out the template.

Then I used a combination of shears, a nibbler, and a drill to cut out to just outside the final shape. Then from there it was a sanding and filing operation. There aren’t a lot of places that I could use the belt sander since there are many details, and I also wanted to work slowly up to the line. So there was a lot of filing going on. Unfortunately, about the time I was done filing the piece to shape, and was really proud of it, I realized I had made a big mistake.

The area where the aft baffle butts up to the cylinders has a tab that is bent down. The cooling fins on the aft left cylinder have a step in them where the rectangular head changes to a cylinder. I had cut and drilled relief holes and slots to facilitate this bending, but didn’t take this step into account. I don’t know why I made that error, the template is correct. I must have laid out the relief holes without referencing the template. Lesson learned. Three hours to make a piece of scrap aluminum. Surprisingly, my colorful vocabulary didn’t make an appearance and I started making a new one.

Today was a repeat of part of yesterday. I spent time double checking my layout to the template. Then checking the template to the engine, then checking my layout again. Then I cut and drilled and filed. We have a new blank for the aft left baffle. I had a little bit of time left before leaving for work, so I rough trimmed the right baffle. I haven’t drilled the relief holes for the bend locations yet, nor have I filed. That will be next work session. I can’t wait to see if the bends work out as planned. Keep your fingers crossed they do.