DiP-FAST DIY

Parts List: 

1. 1x 3" diameter x 2 foot long PVC tube
2. 2x 3" diameter Test Plug
3. 2x 1/4" NPT x 1/4" barb brass fittings
4. 2x One-way check valves
5. 1 ft 1/4" ID tubing
6. Teflon tape
7. Zip ties and velcro straps
8. 1x 3" closet flange (optional)
9. Filter with adapter for 1/4" tube (Shown: Cobetter 47 mm diameter filter holder, 2x 1/4 npt Female to 1/4" barb and 47 mm diameter filters). 
10. Hose clamp
11. Rope and weight (not shown)

Tool List

1. Electric Drill
2. Safety Glasses
3. Drill bits: 7/16 inch plus 1-2 smaller bits
4. 1/4 NPT tap drill
5. Hand Vacuum pump (optional)
6. Tap Wrench (optional)
7. Adjustable wrench (not shown)

Step 1: Drill the holes

1) Mark points approximately 2 inches (5 cm) from each end of the tube.

2) Using a smaller drill bit (I used 3/8"), do an initial drill of each hole as straight as you can.

3) Using the 7/16" drill bit, carefully drill out both holes to the tap drill size.

Safety note: always wear safety glasses and tie back loose hair when operating power tools

Step 2: Tap the holes with 1/4-18 NPT tap. 

1) In one of the holes, hand-screw the 1/4 NPT tap drill in until you are unable to further advance it.

2) Using a tap drill or wrench, screw tap drill into hole until about 1/3 advanced along its length. NOTE: NPT is a tapered thread. Do not fully advance the tap through the hole.

3) Repeat on second hole.

Step 3: Preparing and inserting the fittings

1) Wrap teflon tape around the thread on the brass 1/4" NPT to 1/4" barb fitting until it is tight and wrapped several times

2) Screw fitting into one of the hole. Hand thread until you are not able to advance it further.

3) Using a wrench, tighten fitting until it is fully tight and facing along the tube.

4) Repeat with other hole/fitting.

Step 4: Add tubing and check valves

1) Decide which end will be the "Top" and which will be the "bottom". 

2) On the "top", attach a 2" length of 1/4" tube to the fitting, and the "in" side of one of the check valves to the tube. The assembly should have the arrow pointed AWAY from the brass fitting.

3) On the bottom, attach a 2" tube to the barb fitting and the outlet of the second check valve to th

Step 5: Prepare your filter and attach

Adapt your filter to tubing; for Cobetter filter holder, these are the steps:

1) Wrap teflon tape on "outlet"

2) Clip end of barb (otherwise many brass fittings will not tighten)

3) Tighten brass fitting on outlet

4) Attach to inlet via 1/4" tube. Stablize filter holder with velcro straps.

5) (optional) If using negative control, teflon tape and tighten second 1/4 

Step 6: Attach Test Plugs and place on base

1) On Bottom/inlet end of tube, place one of the test plugs and tighten wing nut until firmly held in place in tube. 

2) Place bottom/inlet end in closet flange.

3)  On Top/outlet end of tube, place one of the test plugs and tighten wing nut until firmly held in place in tube. 

Your DiP-FAST DIY is now ready to vacuum test, use for a negative control, or dep

Lab test and Negative control

1) Attach hand or motorized vacuum pump to outlet port.

2) Place filter or tube from filter into water.

3) Pull 5-10 inHg vacuum using the vacuum pump. Continue to pump until desired volume passes through the filter. 

Field Testing: System prep

1) Attach hose clamp to tube, tie rope to hose clamp leaving a 3-4 ft tail. Tighten hose clamp.

2) Zip tie rope to closet fitting.

3) Tie rope tail to weight (you will need 7-10 lbs).

4) Prepare and attach filter.

Field Testing: Deployment

1) Deploy. See tables for soak times and estimated fill volumes.

2) Recover.

3) Remove filter and freeze or preserve. Remove top cap and pour water into a measuring vessel to get accurate estimate of volume captured. 

4) Clean and sanitize with 10% bleach solution as needed.