Beginner questions about my eBay pump

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Beginner questions about my eBay pump

Author	Message
Romain Lussier	Romain Lussier posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 15, Visits: 145	I'm in the market for a new pump right now and I must say that I have no expertise, but nevertheless willing to buy from local second hand ads (price + no shipping). Could anyone tell me if this pump is worth it or not? thanks a lot!
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Hanaldo	Hanaldo posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I've also found analogue gauges to be pretty useless when it comes to reading the vacuum level accurately. They are useful for determining whether you've got full vac or if you've got a leak, but that's about it. My analogue gauge reads in mm/Hg and psi, and on full vac it goes well past -15psi and well past 30mm/Hg. Which is obviously impossible. But my digital gauge tells me I've got 29.85mm/Hg on full vac. If you are getting pretty serious with infusions, I recommend getting a digital gauge. My analogue gauge worked for me when I first started, but a digital gauge makes it so much easier to find leaks and determine my vac level. Does help when it comes to infusion.
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20_rc51_00	20_rc51_00 posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 95, Visits: 548	The elevation you live can reduce the atmospheric pressure you are reading on the gauge.
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BlackNDecker	BlackNDecker posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	Thanks for the helpful replies everyone. I found this document from West Systems that is a good primer on pumps, hp, cfm, and mmHg. Hopefully others find it useful. http://www.westsystem.com/ss/assets/HowTo-Publications/Vacuum-Bagging-Techniques.pdf
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brainfart	brainfart posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 198, Visits: 1.4K	Do you think -26 mmHg vacuum is sufficient for medium and large projects? It will work for vac bagging. Resin infusion... not sure, might be sufficient for some projects. Degassing of resins: too little vacuum to efficiently degas. Would the vacuum be expected to slowly increase to -30 mmHg if it is allowed to idle for several minutes? No. It has only one pumping head, this will only achieve about 80-100mbar vacuum (this is roughly 90% vacuum, so that would be about -27 inches Hg for the non-SI unit people on this forum). [edit: typo, -27 inches Hg instead of -.27] Edited 11 Years Ago by brainfart
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BlackNDecker	BlackNDecker posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	THanks for the reply. Do you think -26 mmHg vacuum is sufficient for medium and large projects? Would the vacuum be expected to slowly increase to -30 mmHg if it is allowed to idle for several minutes?
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ajb100	ajb100 posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 346, Visits: 4.4K	Judging by the shape of the top, that will be a diaphragm pump so will not have any oil
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BlackNDecker	BlackNDecker posted 11 Years Ago HOT Topic Details
Group: Forum Members Posts: 92, Visits: 251	Greetings all, I purchased a pump off eBay last year. I don't see any manufacturer markings so I don't know what brand of pump it is. My first question is about oil replacement...I don't see a place to put the oil. Is it possible this is an oil less pump? Second question refers to the vacuum...when I place my finger over the port it maxes out at a hair over -25 mmHg. Is this sufficient for vacuum infusion or is -30 mmHg mandatory? Thanks in advance!
	Reply Like 3