One of my clients has a 4.5 Hp, 60 gallon tank air compressor from 1997, one of those oil free types that will drive you nuts in 30 seconds or less. It shattered the connecting rods in the compressor section, probably from over-heating and dirt since the crankcase is open.

Since he isn't flush with cash, he was in a bind. Well, Harbor Freight has component compressors which are near copies of IRs and the reviews are mostly positive. The price is right if the motor can be saved.

Yesterday, I hacked the compressor crankcase with a recip saw, retaining the motor mounts. The bearings are fine so we proceeded.

I built a frame from 1" square tube to hold the new compressor and motor, making a sliding platform from 1-1/2" square tube, flat bar and two 1/2 fine thread bolts for belt tension adjustment. TSC had the necessary pulley (diameter of bore and OD). Sure, it was design as I went but we got it mounted.

Some of the tricks I added were 1/2" steel tube bolt hole liners, autogenously welded to the tubes. Instead of welding to the tank's 12 gauge bracket, I used one existing hole and drilling two more 3/8" holes which are also two of the compressor's mounting bolts.

He has a 14" abrasive chop saw, I managed to make beautiful miter joints, tacking carefully and just needing a bit of 0.023" ER70-S6 filler.

Sure, he could go get a new compressor+tank for $500 but it would still be noisy, this one you can actually carry on a conversation next to it.

Tomorrow, we finish the plumbing. The old one had 3/8" tube for the compressor outlet, the new one uses 1/2". Can you say "choked flow"?