Hello All,

I am new here and my first post. I am making a gravity filter and hydration system. I am not done yet but so far it is coming along great. I am using a an Antigravity Gear 1 gal water bag and some fittings from local hardware store. I have 50 inches of tubing that weighs 1.3 oz for this. 8 inches from bag to Sawyer inline filter from Walmart. The the rest of the tubing for my hydration system. so far the hydration system hold 80 fl oz and weight about 2.8 oz total. The Gravity filter part which is not done should weight about 2.8 oz for the total system weight of about 5.6 oz. But this is a estimate. My flow rate is ok at 1 liter per minute.

Also I am new to this ultralight thing. and I am redong my gear and so far my approx base pack weight will be around 4.48 pounds. I think this is a good start for now and already with future plans could get it down to around 2.8 pounds.

Thanks. James.

You may want to try this all out at home before going "field live". While I have NOT put together a system as you describe, others in this forum have.

I recall from those other threads in which the Sawyer filter is used that the filter MUST be backwashed or filled with water using a home faucet before it will work at the lower pressures inherent in a gravity feed system. And, the filter must be kept filled with water (and not allowed to freeze) if it is to used again before having access to the higher pressure available at a home faucet.

This is not meant to be knock on the Sawyer filter, but it means that you will be carrying the weight of a "full" in-line filter with its water inside.

Perhaps others who have first-hand experience with the Sawyer in-line filter can confirm or clarify my impression.

Hello All,

1st. Backwashing is not a problem for me. I have tested this at home and it backwashes just fine. However I would like a prefilter but the lightest thing I can find would only get the bigger stuff. I think I would try using an old nylon stocking from my wife and rubber band it around the hose connection inside the water bag.

2nd. I have tested the flow rate with tap water several times from a dry filter and have had no problems with the flow rate. Now this is with the filter completely disconnected then connected. but I have noticed a drop in flow rate if filter is open while still connected to everthing. basicly creating an airlock. But I have been able to correct this very easily. so I dont think I will have to carry a filter full of water. If I need to though I can prime it first.

James.

Edited by jbhtek on 03/25/2009 12:30:58 MDT.

Sorry,

As far as the filter freezing. I would never let this happen on purpose. My friend had the MSR miniworks filter freeze and the filter cracked. My backup Aquamira realy saved that trip.

James

This is the DIY gravity filter I pieced together with the exception of the filter from spare parts. Filter rate is ~2L/3min. Bugger is a bit heavy at a tad less than 10oz. Filter wet weighs +5oz.

Just put together a gravity filter as outlined in Jason Klass's video located on this site. After priming the filter flow rate is a slow 100ml/min. Normal for a Frontier Pro gravity filter? If so, mass vs. efficiency between the 2 units.

Edited by arborrider08 on 03/25/2009 13:18:03 MDT.

I can confirm these results. No problem starting out with a dry filter. I noticed a photo in this thread showing the filter only a few inches from the supply bag. A few feet of hose is better because it results in higher pressure. It's also good to have a few feet to the clean water bag so you can reverse the flow for back flushing on an extended hike.