Question on Harbor Freight Vacuum Pump (for filtering)

[Conococheague]

Over the last few months I have designed an built a 2-stage vacuum syrup filter. I will post up about it with pictures after testing. Last March I got the Pittsburgh Automotive 3cfm 2-state vacuum pump. It's intended for pumping out automovite AC lines. I know others on here have used this pump. However, I can't seem to find fittings to connect it to my vacuum lines. The threads into the housing are not NPT. An NPT will engage but only for a thread. I realize that it's vacuum and there's no risk of it blowing off but I'd rather use the correct fitting. I was hoping to find a fitting with a male hose barb to connect to my vacuum line. What have those that use this pump use? Any help would be appreciated. I've searched the internet and my son who's a motor head couldn't find anything. I've tried McMaster Carr. Thanks.

Conococheague

[TapTapTap]

A quick internet check shows that the pump comes with Acme NPT. See this link for info on acme:

https://www.hunterindustries.com/support/whats-difference-between-acme-thread-and-npt-or-bsp-thread

[Conococheague]

Thanks TapTapTap. I tried to find fittings for the Acme NPT but couldn't find any. Ended up just putting teflon tap on a regular NPT hose barb and screwed it in. There's enough thread engagement to make a good seal. I would never do this in a pressure application but I'm not concerned with vacuum as the small force is in the direction to pull the fitting in. I think it will work fine.

Conococheague

[DrTimPerkins]

Small pumps such as this can blow out a fine mist of oil, especially when you're pulling a bit of vacuum. This can be a problem (oil contamination) if you have open syrup in the area that you're using the pump close to. An oil mist filter is a good idea https://www.mcmaster.com/9218K81/ but will cost you as much as the pump did. The alternative is to move the pump to a well-ventilated area away from where you're filtering/packing syrup.

[Conococheague]

Thanks Dr. Tim, I never thought about the vacuum oil mist. How far away from open syrup would you consider a safe distance? I can run a longer hose from the vacuum pump to the filter if it's a reasonable distance. Alternatively, or in addition, I can put a small fan near the pump to blow the oil mist away from the filtering area. Would this work? Thanks.

Conococheague

[DrTimPerkins]

You can do do whatever you find that works to keep the oil away and out of the syrup.