dust extraction pipe.

[Tonyz]

I read in a hints and jigs mag about using the cardboard rolls that carpet is wrapped around.
I just a coulpe and later will post a report but they are 4'dia a standard PVC joiner or elbow fit them and a lot cheaper than plastic storm water pipe. Whats your thoughts, or you going to wait and see if I survive this trial.

[boban]

The 100mm sewer pipe is not that expensive (<$30) for 6m. Read Bill Pentz's and you will find that the recommendation is actually 6" or 150mm pipe.

[Tonyz]

I hear you Boban but, mate, free is free. May not do a proper job but I,ll try and see at least it wont kill me.

[specialist]

I don't see why it wouldn't work, my only concern is that the paper that is rolled on the inside will start to unroll and clog the works.

specialist

[Harry72]

Id bet that it will cause you a massive air flow drop, those cardboard rolls are very thick 10~15mm. At every join using SWD connections you will have steps because of the differing thicknesses... this will cause "eddy currents" at every join!
The cost saving will not out weigh the flow restrictions, you could do a double run but the cost of the extra connections... and still not have as good as flow as a single 4" SWD pipe.

[dazzler]

... this will cause "eddy currents" at every join!
.

Put your ear close and you will here "the money or the mob".... and "go pies"...

[bpj1968]

Apart from the eddy currenst mentioned by harry.
the diff between 100mm and 90mm isn't a 10&#37; drop in volume, but in fact 19%

same as 100 mm going up to 150mm isn't a 50% increase but a 125% in volume, along with the increase in volume there is also less resistance, same as straight vs curve vs conceterna.

$30 gets 6 metres, how many metres would you need?
using the cardboard to experiment with the layout would be a cheap no cost excercise

[TTIT]

So where do you get this 100mm / 4" sewer pipe???????????? All the plumbing joints out here only have 90mm then jump to 140ish Can't find anything that the 100mm connections will fit

[Tonyz]

TTIT ....Iam with you man wheres the answers

[boban]

Bunnings has it, as does every plumbing supply shop. 100mm is standard sewer pipe. 90mm is the stormwater pipe.

BTW- Bunnings has now started to compete with the trade supply places on price. I thought I would never see the day.

[Tonyz]

sewer pipe eh now thats really going down the perverbial hole he he he he

[TTIT]

Bunnings has it, as does every plumbing supply shop. 100mm is standard sewer pipe. 90mm is the stormwater pipe.

Gonna go look into this tomorrow Buggers told me they had nothing at 100mm - and we do have sewers - I think!

[boban]

While you are there buy yourself some straight joiners. You will find that your flex hose fits inside very easily. I know they have it because I got some from there when our plumbing plus shop was closed. Most my Bunnings shopping is after 7pm. Only problem is they close the drive through gates and when I got my length I had to carry it through the shop.

[Tonyz]

Oh you poor bugga I feel sorry for you.So? you manage to carry anything inside it?

[QC Inspector]

Tonto

I've been lured out of my long time lurking status to add a bit to this discussion.

There was an article in Woodwork (an American magazine) a number of years ago about a guy that used cardboard tubes for his dust collection system. I'll add that I had had the same thoughts many years ago long before I saw his article. Anyway he used duct tape for some of the joints and glue and cotton cloth for reinforcement on others. He also made some large radius bends by cutting out wedges at intervals but leaving a bit to hinge on for the bends, finishing with the glue and cloth. While probably not the best system from a friction loss point of view, it was cheap and worked.

I have another source of the tubes. The tent and portable/temporary structures makers. The heavy plastic coated cloth comes on it with the largest that I've seen being 4" ID x 12' long with the walls almost 1/2" thick (100mm x 3600mm x 12mm) There is one next door to the plant I work in and they throw out one or two of the large ones each month. By the way they also throw out plastic pipe (3 or 4 a month) in the same large size except the walls are a fat 1/4" thick (7 or 8mm). Companies that make tarps for semi-trucks might be a possible source too.

Since reading Bill Pentz's site I'm going to (someday) make my system with 6" (150mm) equivalent diameter ducting of wood. Box sectioned with coved corners or corner blocks for an approximate octagonal cross section. A bit different I know but I have a big stack of softwood from crates 14' long and my run is straight (long narrow basement shop).

I am going to try to attach a picture of a WoodRat mount that I started a while back and have to get back to that has some of the cardboard tubing, used to make a better airflow transition at the hose connection.

You're not the only one with a far fetched idea or two.