bridge bearings

[SP1]

I tried using vacuum, and all it did was allow the bubbles to expand, and ruin the casting. Only one more question, Just how much pressure is needed ?
If it is under thirty pounds/square inch, an old pressure cooker pot, and an air compressor ( air brush ) should work well enough.

I have to admit, that I dont know how much pressure is needed. I made a few attempts with with an old pressure cooking pot and an airbrush compressor. They all failed. Maybe I should investigate that further - but there is so much to do and so little time.