My version of the lift has three welded joints. In Step 10 there are modifications that you might use to avoid any welding.
Most of the carrier is built of EMT conduit. EMT is short for Electrical Metallic Tubing. This conduit is cheap and available at most home repair centers. Welding EMT can be hazardous so please read through my Instructable about how to do this as safely as possible (https://www.instructables.com/id/Welding-EMT-Conduit/).
My cost was about $20 for the carrier parts I bought (conduit and two tiedown straps).
Step 1: Select a Bottom Bracket Shell (BBS)
Step 2: Prep the BBS
Step 3: Determine Your Measurements
The third measurement is the offset from the hitch ball to the rear door (11" in my case).
Your dimensions may vary.
Calculate these two lengths:
Length #1 is measurement #1 minus 12". (54 - 12 = 42" in my case)
Length #2 is measurement #2 minus 6". (30 - 6 = 24" in my case)
Step 4: Add Main Tube
Mark the midpoint of this tube and grind (or burn) the galvanized coat off for about 3" on each side of the mark. Clamp the main tube "sorta tight" so it is centered over the intersection of the down tube and the seat tube on the BBS (Photo 1). Hold the BBS flat on the floor and level the main tube so it is parallel to the floor (Photo #1). Tighten the clamp, double check the position and weld it in place (Photo #2).
Step 5: Add Pivot Tube
Start your first bend 24" (length #2) in from one end of the 3/4" conduit (see Photo 1). Make a 90 degree bend.
Insert the long end of the bent tube through the main tube , position it and mark the location for the start of the second bend.
Make the second bend parallel with the first bend and stop it at 90 degrees (see Photo 2).
Measure up from the top of the second bend for 24" and cut the extra tubing away.
Step 6: Bend Carrier Tubes
Photo #2 shows the carrier tube with the two 1/2" attachment tubes welded on. These two tubes are positioned 11" from the front side (measurement #3 in step 3).
A piece of 5/8" garden hose (slit lengthwise) is taped to the front side of the carrier tube to cushion where the carrier sits against the SUV. Two pieces of bike inner tube are slipped over the arms of the carrier tube.
Photo #3 shows the attachment tubes sliding into the pivot tube. Holes are drilled through the pivot tube and attachment tubes so pins can be inserted to hold the carrier together.
Step 7: Add Mounting Straps
Step 8: Loading the Carrier
You can also just lift the bike or trike up onto the carrier arms and strap it in place.
Step 9: Tools and Parts List
1/2" tubing bender
3/4" tubing bender
42" piece of 1" EMT for lower pivot tube
10' piece of 3/4" EMT for pivoting arm
10' piece of 1/2" EMT for top rack
2 ea. ~12" scrap pieces of 1/2" EMT for carrier tube attachments into pivot tube
Donor bike frame with 2" BBS
4 ea 1.5" long 1/4" hex bolts with lock washers and nuts
2 ea bicycle tube pieces ~24" long to cushion arms
2 ea Tiedown straps
6' of 5/8" garden hose
Step 10: Non-Welding Option
1. Trim all the tubes off the BBS.
2. Bore a 2" diameter hole at the center of the 2 X4.
3. Drill a 1/4" hole through the 2 X 4 and the BBS and bolt them together.
4. Use four U-bolts to attach the pivot tube to the top of the 2 X 4.
5. Use two 1/4" hex bolts to attach the hanger tube to the 1/2" linking tubes.
Use "J" bolts to link the attachment tubes to the top rack.