deadrush - 23-2-2025 at 20:18
So a year ago I bought "2- Stage 50L/m Oil Free Lab Vacuum Pump Oilless Medical Mute Pump HZW-165 (110V)" (or see link at bottom. Now long story
short, I need that piece out that would normally be removed with an Allen wrench. However, it's stripped... badly. Good news is I have a variety of
parts to replace it (1/4in male npt). Anyone have a good idea what I should do?
I tried contacting the seller, bust, and I tried to find a replacement for the entire piece but unless this pump, which is fantastic btw, used a
positive pressure air filter ... well I could find nothing that I KNEW would work.
https://www.amazon.com/Stage-Vacuum-Oilless-Medical-HZW-165/...
j_sum1 - 23-2-2025 at 23:13
If it is just a matter of getting it out, I have previously had success by hammering an oversize torx bit into the burred hole and then carefully removing the screw. Best to work by hand as applying too great a force or having the bit slip
can lead to further damage of the screw.
[Edited on 24-2-2025 by j_sum1]
Sulaiman - 23-2-2025 at 23:42
look for "bolt extractor", very cheap mini-kits are available via online shopping and hardware stores probably have stock.
the tapered thread is anti-clockwise.
hammering a hex key in also works sometimes,
worth trying before ordering then waiting for a bolt extractor.
some hex keys have a hex-ball end,
or you can file a hex key to fit the new hole.
Sometimes just a tapered straight blade screwdriver bit of just the right size can be 'persuaded' into place.
a squirt with wd40 or equivalent hours/days before you try may help un-freeze the screw/bolt.
bnull - 24-2-2025 at 02:18
If you have a way to cut a couple of opposite notches on the rim of the bolt (with a dremel), you can use a flat screwdriver. An alternative is to use
a drill bit to deepen the hole and hammer an Allen or torx bit into the hole. Another alternative is to use a flat screwdriver, smaller than the hole,
and use it at an angle (~30° or so, it depends on the dimensions of the hole): put the screwdriver in and apply pressure while slowly rotating it.
These things happened to me so many times that I had the opportunity to try different methods.
Twospoons - 24-2-2025 at 12:33
I would go with a screw extractor, as Sulaiman suggested. They're cheap enough and you should find a set at your local hardware store. For a 1/4" NPT
it should work well. Be gentle, the extractor bits tend to be brittle, as they are hardened so they bite into the screw body.
Heating the body may also help, especially if some nitwit has used threadlocker on the screw.
FableP - 24-2-2025 at 17:25
When I was working on density gauges, the first line of attack that didn't involve the gas axe was a set of reverse thread drill bits in a drill press
(obviously running in reverse). Most of the time before the drill got 1/2 way through the stuck part, it had gripped it and unscrewed it. You need to
run a nice slow speed, the drill press helps keep everything aligned and once you get a good bight on the grub it should come right out. If you don't
get it out on the first pass (unlikely) you can move up a size and repeat the process. Unfortunately a good set of reverse thread drill bits isn't
cheap. Success is lessened when using a hand drill, with a greater chance of breaking the drill bit in the grub.