Finally started work on the quad jet....step by step with pics.

[mike(swWash)]

Here's what I've got done this week. It took about 4hrs to get this far. I hope to have time to finish it next week.

It's a 3" jet. I have no intention of using it right now but it was material I had laying around the shop and thought for my 1st try, why not. I need to pick up some 2 and 2 1/2" stainless exhaust pipe to build the one I'll use.

Step 1. Put 4 marks equal distance apart around the 3" pipe then drill. I used 1/8" sch40 pipe for the jets since it is about 1/4" i.d.

[/URL]
Step2. Cut a wedge at approx. 11degrees for use later.

[/URL]
Step3. Insert bit in the hole and begin reaming the hole to the desired angle.

[/URL]
Step 4. Keep drilling until the hole is at the proper angle. Make sure you are lined up straight with the pipe.

[/URL]

[/URL]

[/URL]

[/URL]
Step 5. Check hole alignment to be sure the jets will converge in the center.

[/URL]

[/URL]
Step 6.This was the hardest part..... Insert small pipe into hole at the proper angle, mark it and cut it off as shown.

[/URL]
Step 7. Insert jets and weld to the 3" tube so the angle cut is flush with the inside of the pipe....my welds look like crap, but oh well they're sealed and solid.

[/URL]
That's all I had time for this week.
Next I have to ream the 4" washers so the 3" pipe will fit tight and weld it up.

[/URL]

[/URL]
I still have to cut in and weld the pressure supply tee for the jet water at a 45 degree offset so no deadheading.

 

Amazon Forum Fav 👍

A History of Mining on the Kenai Peninsula, Alaska - Grab it through Amazon!

[russau]

It appears that your trying to weld a large mild steel washer to the stainless steel tube. if so , be prepared to have your weld crack next to the mild steel washer when it cools ,if this is your plan! no problem!PRE and POST heat the weld area to prevent it cracking! do a practice weld on some scrap to check it out!

 

[Timberdoodle]

Looking good Mike! I really like that you recognized that the jets can be located inside the pressure housing which reduces the work welding to the housing and allows them to be short (less loss) providing they are long enough to provide directivity. They looked good to me. One thing I picked up on was "I used 3/8" sch40 pipe for the jets since it is 1/4" i.d." I believe sch40 internal pipe dimension for 3/8" is .49 or 1/2", probably just a finger fudge in the write up as it looked like you calculated the total volume for 4 jets at .49 based on a standard 3" log jet for roughly 150gpm@30psi.
It's going to be challenging to supply the chamber with just under 1/2" between the pipes with 150gpm. There are options, the easiest being to use a true 4" tee and neck it down with a cone reducer to a 2" feed. STAINLESS STEEL WELD TEE 4" SANITARY PIPE TUBING 102mm

 

[mike(swWash)]

Yep I typed the wrong size, I meant 1/8" pipe. I corrected it in the original post.
I may see if I have some 6" laying around to use for the outer barrel because I believe you're right about not getting enough flow into it for the jets to work.
I'll use the 4" piece for my 2" or 2 1/2" dredge if I can make up my mind which.
I don't have a big enough pump nor any intention of ever using this jet, but I may take it to work when done and hook it to a waterline to see what kind of suction it gets just for fun.

And you're right russua, the first pass will crack but the second should hold well.

 

[Timberdoodle]

Mike, the outer housing won't be a problem if the jets are actually 1/4"id. Now were talking 50gpm vs 150gpm. A simple 1 1/2" or 2" feed will work since the flow speed will be under 10fps.

 

[mike(swWash)]

One step closer today, got the 1 1/2" jet supply connection cut in and welded up on the 4" outside tube. I still need to cut the washers to fit the 3" inside tube.

 

[russau]

Well I bet Hoser will like seeing the feed for this jet installed at your location! I added a drain on the bottom of my jet to remove any material that does get sucked up into the jet. Ill probly never need it but its there for the day I do!

 

[mike(swWash)]

Great idea to have a clean out drain. Crap, now I have one more thing to add . Sad part is after all the work in this 3" jet unit, it'll probably just hang on the wall of my shop until someday when I decide the 2 1/2" I'm building just isn't enough
It's been a good 1st project and a good basis for improved ideas for the next one that will be similar but much simpler to build.

 

[Timberdoodle]

I use some basic side input entry parameters to prevent loss of psi due to restriction of flow or bends etc.. which hopefully will help in your next build.
1. determine total flow required for the inlet based on jet size and number of jets (in you case approx. 50gpm@35psi)
2. Size the inlet for around 10 fps (feet per second) flow rate which has very little loss in 90's or tee's (in this case 9 fps for 1.5" feed)
3. Take the circumference of the feed and multiply by the depth between the pipes (1.5" has 4.7" circumference X .5 depth for an area of 2.3) since the area of flow between the pipes is greater than the area of a 1.5" feed (1.7" area) this tells you that the flow speed is going to be less than 9 fps. If there is less area which would create a restriction and increase friction loss, you can increase the depth between the pipes by using a larger housing or increase the feed diameter by using a cone or oblong feed until the area is greater. An oblong feed that supplies flow equally to both sides of a jet is preferred over a directional feed.
4. Make the housing length at least double the diameter of the input feed and locate the feed to allow flow into the chamber for 360 degrees of the input to ensure the circumference calculations are allowed for and flow is not restricted to only 2 directions.

Their are other ways to factor for size etc.. but these basic parameters have served me well for jets that use a pressure housing. Probably the greatest mistake that is made when folks build a jet like this is that they start with a feed size for a jet orifice that is the same that they used for a standard log jet and try and feed the pressure housing with a fast flow rate (20-30fps) which results in greater friction losses (psi loss) when a transition is met (tee etc..). By factoring the build from the start, the flow speed will be compensated for and more psi is delivered to the individual jets. What results from making a jet housing too restrictive is that you will find that increasing the pump speed does not result in a linear increase in the jet power/suction as more velocity through these restrictions increases friction losses dramatically. So for the 3" jet you built using a 50gpm supply and 1.5" feed there was enough area and good flow speed. If the jet needed 150gpm, a larger housing, larger feed, or other form of compensation would be required to keep from losing psi.

 

[mike(swWash)]

Oh man, now my head hurts and I think my brain is my bleeding I'm not good at math and don't understand formulas for the most part.
Hell, where I went to school algebra and such was only for A+ students..... Illwaco High class of '77....we learned about fish, fishing, counting fish, rearing fish and canning fish.

I fly by the seat of my pants and now as a former pipefitter I have some very, very basic knowledge of fluid dynamics that's why I put the feed water tube offset for less restriction. Like I said, I doubt I'll ever use it but once finished I may have a contest to give it away for someone to use. I only do it because I can.
The build design I'm doing for myself will be very different from this one, more clearance, a whole different(simpler) type of educator(orifice/jet) setup, that anyone can make that have basic welding skills or access to them, a chop or table saw and a drill for hopefully a LOT less than $100 depending on size.. and will work from 1" to whatever. No patent, no profit, just info for anyone to use after I do some testing and asking you many technical questions in the future if that's ok with you.
What can I say, I've already lost out on 2 ideas I've given away and other$ have run with. I just like to think and build stuff

 

[Timberdoodle]

I started building my own equipment the same way Mike. My background is in electronics/RF engineering getting my start in the Navy after growing up on a small farm so I had to learn about fluid dynamics from the ground up over the past 5 years. I started by simply building and testing equipment and have learned from the experiences of success and failure (mostly failures early on) that it was important to do research and apply the math to help scale equipment to the next size which reduced the effort to build and test 10 prototypes. Most of the math tools used for piping systems are online so they really aren't very complicated. I'd be glad to help if you have any questions.
The way I look at the patent process is that it's a way to keep others from patenting your work and then telling you that you can't build them, so starting a paper trail is important if you ever decide to sell a product. Surprising how many patent trolls are out there when I looked into it.
Keep up the good work Mike!

 

[russau]

Yep Mike I also like to make things and enjoy shareing ideas. we have a couple of threads going on over on another site that shows a vibrating /pulsed (VP) device that adds pulsed water to a fluidbed for better recovery than just a fluidbed alone. we are currently rehashing this idea and possibly improvements over the original device. its over on yahoogroups (I hope this isn't breaking a TN rule) the only requirement we have is that this design NOT be made for resale! one of the co-design owners (Dave Bryce "Zooka") made/asked that this be so! and so far this has been done!

 

[mike(swWash)]

Thanks for the help, advice and info you've all given me. This is my 1st dredge build and it's been fun.
Now I have all the parts for the 2.5" build for my next days off.

Timberdoodle, what do you feel would be an efficient size for 8 orifices or even 16? I can make them in graduations of 64ths if needed. I'm thinking 8 at 3/16ths" or 16 at 1/8th" sounds about good. My pump has a max of 55psi and free flow output of 60gpm at full throttle. Do you think Ill get enough suction with the jet set inline 5' before the sluice and 10-15' of hose to the nozzle intake?

 

[Timberdoodle]

Thanks for the help, advice and info you've all given me. This is my 1st dredge build and it's been fun.
Now I have all the parts for the 2.5" build for my next days off.

Timberdoodle, what do you feel would be an efficient size for 8 orifices or even 16? I can make them in graduations of 64ths if needed. I'm thinking 8 at 3/16ths" or 16 at 1/8th" sounds about good. My pump has a max of 55psi and free flow output of 60gpm at full throttle. Do you think Ill get enough suction with the jet set inline 5' before the sluice and 10-15' of hose to the nozzle intake?

Hi Mike, the smaller jets will work very well with 4-6 jets since they are close in proximity to each other. You don't want to make too many jet's resulting in very small jet size or they will clog and you will be facing the problem with an infinity jet without the ability of opening the gap. I don't like to build them under 3/16 unless a fine screen is put over the footvalve.
Did you buy the WX15 or is this another pump? really helps to know what volume at 30psi and a pump chart is best if you don't know. I'm going to use 40gpm as a baseline and this should be close if I reference a WX15 chart which has a little more volume but the same psi.

8 jet's at 3/16's will be 45gpm range which means slightly less psi but still close enough
4 at 1/4" would be 40gpm

You will get good suction with 5ft after the jet and 10ft before the jet. even better if you reduce the length after the jet to 1-2ft, but if your working shallows the 5ft length after the jet will help regain prime if lost.

Keep in mind that these are truly low volumes and pushing the limit for a 2.5" jet and making everything right is critical to get good performance. You can get awesome performance using these numbers for a 2".

 

[mike(swWash)]

Yep I picked up the wx15, At $200. and 20lbs I couldn't pass on it.

 

[Timberdoodle]

Yep I picked up the wx15, At $200. and 20lbs I couldn't pass on it.

Nice!. Great pump. Since it's rated for 72gpm free flow it will give you a better buffer to increase psi if needed.

 

[russau]

Good buy!!!!! I would have bought that myself and I don't need another pump!

 

[mike(swWash)]

Ok, now I'm thinking 6 3/16th jets might be on the perfect ragged edge with just a bit of fudge room for my mini pump running a 2.5" dredge. Enough flow, and vacuum drag to pull/push to small rocks and silt off the bottom and put gold in the sluice..........?? My dredge nozzle will either have a 2" restrictor ring or more likely a pin through the middle to keep the big stuff out.

Now I need to start thinking about sluice size and setup (hint 9"wide x ? )with gold hog mats that I still need to order.

 

[AimSmMissSm]

I see you have been busy Mike. I cant wait to see you dredging. I have a couple new areas I have been prospecting that you might be interested in. It will be a drive and probably a camping trip but its bigger gold then we normaly get.

 

[Timberdoodle]

Ok, now I'm thinking 6 3/16th jets might be on the perfect ragged edge with just a bit of fudge room for my mini pump running a 2.5" dredge. Enough flow, and vacuum drag to pull/push to small rocks and silt off the bottom and put gold in the sluice..........?? My dredge nozzle will either have a 2" restrictor ring or more likely a pin through the middle to keep the big stuff out.

Now I need to start thinking about sluice size and setup (hint 9"wide x ? )with gold hog mats that I still need to order.

Mike, the best advise I can give is to first build the jet and test it with hoses attached to determine your total flow rate. Being that your jet is using much less water than a standard log jet will result in less total flow through a sluice and since gold hog mats like fast water you are going to want to know the total flow rate to determine the width of the sluice with the mats you want to run. If all goes well with the jet, you should be able to achieve a suction rate in the range of 125gpm on a 2.5" hose, add that to the jet volume of approx. 35gpm for a total of 160gpm of total flow. (a standard 2.5" jet would result in approx. 125gpm draw and 100-125gpm jet volume for approx. 225-250gpm total flow) This means everything in the system (flare and sluice) should match your flow rate to work properly. It can be difficult to measure this much volume with a bucket or 50g drum. Reggie Gould mentioned a flow measuring technique in his articles and I have tried and verified this and it works great. Here is a link that explains the method. USBR Water Measurement Manual - Chapter 14 - MEASUREMENTS IN PRESSURE CONDUITS, Section 13. Trajectory Methods unfortunately the charts don't directly mention a 2.5" pipe, so some interpretation would be necessary or find another source that has a 2.5" chart. Hope this helps, it might seem a little overwhelming looking at these charts at first, but they are actually pretty easy to use once you try it.