My wildest project

PILOON

Well-known member
Messages
177
Good Post Points
54
Location
North of Montreal
Welder
Hobart 200 stick
My background was in aviation.
A client that operated DC3's wanted more comfortable seating for his passengers.
He also had a set of Convair seats but they were too wide to allow minimum aisle space of 16 inches.
My challenge was to modify them to fit. Like cut out 3 inches per seat frame.(1.5" per passenger)

While I did weld I was not a certified aviation welder but I put forward my proposal which had to include testing.
The process was to cut out sections of tubing thus narrowing the seat frames and rejoining with fish tail splices as was outlined in aviation technical manuals.
We received the approvals and proceeded to fabricate the prototype subject to testing.

Criteria was to simulate a crash with 2 adults seated and strapped in.
6 G* impact with no structural deflection followed by a 9 G final test with some noticeable deflection.

I bolted seat tracks to the concrete floor, rigged a certified strain gauge from the 'seat belts' and we proceeded to apply tension using hydraulics.
The other end was chained to a building vertical structure.

The 6 G test went off just as expected. Absolutely no deflection as checked with a straight edge.

Then comes the 9 G test.
At about 8.5/6 G's the flooring anchors pop out!
Inspector , with glee claims 'failure'.
BUT, his boss, the regional director was present (and a decent guy that used logic).
He checked for deflection, found none and promptly proclaimed a pass.

Basically he used good logic. It was that minor extra that cause a failure since there wasn't even a measurable bend or curve.

*2 adults @ 170 lbs= 340# X 6= 2040 # for first test.
2nd test needed 3060 lbs of pull and the anchors came lose at about 3000 lbs.
 

PILOON

Well-known member
Messages
177
Good Post Points
54
Location
North of Montreal
Welder
Hobart 200 stick
Any pictures of the weld patterns?
No since it was some years ago but I used an aviation standard procedure for splicing tubular structures as outlined in many publications.
Basically calling for sleeves with fishtailed ends and rosette welds.
Tubing used was 4130

Thinking back I'd believe aviation structural welds could be applied to modifying tractor roll bars and such.
 

Yomax4

Well-known member
Messages
169
Good Post Points
52
Location
MN.
No since it was some years ago but I used an aviation standard procedure for splicing tubular structures as outlined in many publications.
Basically calling for sleeves with fishtailed ends and rosette welds.
Tubing used was 4130

Thinking back I'd believe aviation structural welds could be applied to modifying tractor roll bars and such.
Cool stuff. Did you have to use 4130 or did you use 80SD-2 ? Nice project.
 

California

Well-known member
Messages
378
Good Post Points
144
Location
Sonoma County
My background was in aviation.
A client that operated DC3's wanted more comfortable seating for his passengers.
My not at all related story about DC3 seating, I enjoy telling this story:

On vacation with a deadline to get back. I crossed the border from Ecuador into Colombia and went to the airport for the scheduled DC3 flight into Bogota. "Sorry, we've sold all the seats". The posted schedule had a flight an hour later so I insisted on taking that one. "We're not selling seats on that one". I insisted, I really couldn't lose a day getting back. Reluctantly "Well ok but you're not going to like it". They unfolded a passenger seat for me and I flew alone with a load of chilled beef cadavers.
 

PILOON

Well-known member
Messages
177
Good Post Points
54
Location
North of Montreal
Welder
Hobart 200 stick
OK, we've intro'd aviation into this discussion.

A client had a Grumman 'Goose' (amphibian) that he wanted to make into a flying camper.
I had seat cushions fabricated that when positioned made a seat but when laid out made 'wall to wall' beds.
Air regulations state that seat restraints must meet crash specs.
So what I did was create long seat belts that attached to the (certified seat rails) and his passengers would sit on those thick cushions all while being restrained by certified belts.

OH, I enjoyed creating 'work arounds' all while satisfying clients.
Like providing enough fuel to ferry a single aircraft across the Atlantic all while meeting ICAO/FAA/Cdn regulations.
Gee, must have modified 2-3 dozen A/C with quite a few repeat clients.
Word got out to the ferry pilot crowd that I was the 'go to' guy.

More than a few times I made newspaper news as well.
Once I modified a Cessna for a 'round the world' event that the owner sold autographs on his plane to raise funds.
Well I was the first to sign and 2 weeks later I received a call from a fellow shop owner in California that saw the AC c/w my signature to compliment me for the job. (small world)

Another newspaper compliment was when I prepped 5 crop dusters for trans Atlantic ferry flight to Africa. (all in a 30 day time frame)

Oh, I had fun! (LOL, supposedly my job)
.
 

Aczlan

Active member
Messages
40
Good Post Points
9
Interesting, I have a friend who used to ferry single-engine planes around the world, I wonder if he was one of your clients.

Aaron Z
 

PILOON

Well-known member
Messages
177
Good Post Points
54
Location
North of Montreal
Welder
Hobart 200 stick
Most recent 'wild project' was to modify a 4 post vehicle lift into a freight elevator for a storage facility,
We found a model of lift that went 12 ft, and used that.
Welded a checker plate to close the gaps between the wheel ramps, created a 'slope' to push carts onto the platform.
At the upper level we made a hinged plate/ramp that would meet the elevator when it reached the floor level.
The entire lift was then 'caged' with panels to prevent cargo from falling off.
We had a very creative electronics guy make us control circuitry to operate the lift.
Safety circuits galore like U MUST have both doors closed to operate.
One push for up, one push for down.(switches, that is).
Very satisfying a project to have created,
When designing we always did so with safety in mind using all sorts of 'what if' scenarios.
Big placards at both levels state, "No passengers" (in both official languages).
We also considered that folks would occasionally have little kids with them when storing goods so we had to think 'child proof' as well.
Quite a challenge but rewarding once completed and all working as planned.
As to cost, well, nowhere near what a freight elevator would have cost.
 
Top