Building the gantries

Well, its been a few weeks since we last updated y’all (yes, we are from Texas). We’re sorry, life got in the way! Despite the lack of posts we have been slowly working on Aurora.

So now that you’ve decided to do a full monty renovation, how the heck are you going to get your shell off? Come with us as we show you how we lifted the aluminum shell off of Aurora to get down to the steel trailer.

If you’d like to skip ahead to the good stuff, feel free to check out our video on our YouTube channel below. Otherwise, feel free to read through the specifics on how we erected gantries as we prepare to lift the shell off of our trailer frame.

There are a couple ways to get the shell lifted up, and depending on who you ask, some are better than others.

The first option is to leave the shell over the trailer bed and work on the steel trailer in situ like Ian Miller did with his coffee house trailer on Miller Garage. The second is to use jacks and stanchions to lift the shell and then remove the trailer out from underneath, like Kyle and Olivia did at Drivin’ and Vibin’. A third way is to build gantries to hoist the shell off the trailer and set the shell on the ground.

We decided that the gantries would be the best solution for us. We liked the idea of getting the trailer completely out from under the shell to make it easier to work on, and we could move the trailer frame to the barn to get it (and us!) out of the weather. Another consideration since we have a 1970 model, is that our Airstream has aluminum that wraps from the side walls to the belly pan. These prevent us from easily placing cross members underneath the shell. Finally, by having gantries and hoists we can also lift the axles more easily later on and we can flip the steel trailer for replacing the belly pan.

First on the to do list is to get some materials from “the Depot”. I’ve never been much on lists and drawn schematics before starting a project, and I know it drives Kate crazy, but I scoured Airstream Forums and some Facebook groups to see how others put theirs together. We decided that using 4 x 4 pressure treated lumber would probably be easiest and would hold up to the environment. I had originally planned on using some 6 x 4s but they were way too heavy to be moving on my own and honestly the gantries only have to support the weight of the shell for maybe an hour at a time. We planned to use 1/2 inch lag screws to connect the main members and no drill lag screws for the corbels. Below is a list of our materials.

Gantry Materials:

4 in. x 4 in. x 12 ft. Pressure Treated Pine (10)
1/2 in. x 8 in. Zinc Plated Steel Hex Lag Screws (8)
1/4 in. x 6 in. Powerlag Hex Drive Screw (16)
1/2 in x 10 in. Eye Bolt with Nut (2)
1/2 in. Zinc Plate Washer (2)
10# x 3 1/2 Constrution Screws (1 box)

We already had the tools from previous projects like our miter saw, impact driver (way easier than doing it with a wrench), drill, impact sockets and drill bits.

First things first, we cut four 6-foot sections of 4 x 4 for the bases. We laid each one perpendicular to a 12-foot length then drilled a hole for the lag screws. An impact driver and 19 mm socket make quick work of driving the lag. After this, we cut miters into 3 foot sections of 4 x 4 to make the lower supports. We used Powerlags to attach these to the main post and base. If you haven’t used Powerlags before, we highly recommend them. No pre-drilling and they’re rock solid. To finish off each tower we then pre-drilled a hole for the upper lag screw. Now we just repeated 3 more times.

Next up is the cross members. these were pretty easy. We drilled holes at each end for the connection to the columns and a hole dead center for the eye bolt. We did end up having to attach a spacer board of 2 x 4 to the top since “the Depot” didn’t have any 8-inch eye bolts. A few construction screws and a few minutes with the torque wrench and we were done.

Now to put it all together. The first one I mostly did by myself, with a little help from Kate to lift into position. The second was much easier as I had my dad and brother in town to help (they had come up to meet Charlie). We propped up one column at a time using 2 x 4 to brace it. Lag screws were driven into the cross member and side supports were placed to reinforce the connection. We then hooked on the hoist and up the whole thing went. We were very careful during this part so the chains did not hit the shell (we don’t need any more scratches and dents to remove). Once we moved the gantry into the final position, we drilled holes in either side and drove some scrap rebar we had lying around into the ground to anchor the whole thing. We drove a piece of rebar out to the side and used hauling straps to give some lateral support.

Building the gantries was actually one of the faster projects. We probably spent about 3 hours cutting, drilling, screwing, and securing both. Compared to the other steps so far this was positively satisfying. Tune in to our upcoming post on actually lifting the shell!