Page 8 of 17 FirstFirst ... 345678910111213 ... LastLast
Results 106 to 120 of 254
  1. #106
    Join Date
    Jan 2014
    Location
    Sydney Upper North Shore
    Posts
    4,464

    Default

    When I contacted them re 5" pipe, they couldn't use a supplier over here ( they have some sort of reciprocal arrangement with other States?) because they only sold in bulk in NSW. They could however send me two lengths but the freight was $110. Even then, they were approx. $8 cheaper than any supplier in Sydney?They were however more than happy to send fittings by bag/satchel.

  2. # ADS
    Google Adsense Advertisement
    Join Date
    Always
    Location
    Advertising world
    Posts
    Many





     
  3. #107
    Join Date
    Feb 2016
    Location
    Canberra
    Posts
    5,124

    Default

    BobL, do you have any pictures as to how the flexi stays secured in the pipe with the wind on thing?

  4. #108
    Join Date
    Nov 2011
    Location
    Adelaide
    Posts
    259

    Default

    Quote Originally Posted by Trav View Post
    Thanks bob. I'd missed this thread before. Great thread, especially as it relates to both cabinet ports and dust extractor inlet ports.

    I'd posed the question in my thread, but it is probably more relevant here. Apart from making a bell mouth inlet, has anyone found a suitable product that can be simply modified to form a bell mouth? I don't have a lathe but would be willing to hack into a pot plant or similar if that would work. Otherwise it's option 2 for me.

    A question for BobL - would a 'bell mouth' with a large diameter round over bit work better than a taper?

    Trav

    As you are thinking, the bell mouth does not necessarily need to be turned onto the inlet tubing itself, it can be a projection/extension piece added to the inlet opening.
    Think of it like half a curtain ring /torus
    This approach is found in inlets in carburettor air filter housings

    Router round over bit and MDF with a hole in it is an option.

  5. #109
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    Quote Originally Posted by woodPixel View Post
    BobL, do you have any pictures as to how the flexi stays secured in the pipe with the wind on thing?
    The hole is turned into the end cap just big enough so that it is a tight fit for the flexy.
    I also put a taper on the outside of the hole as this helps the flexy go into the hole (see picture below)
    Obviously not too tight a hole otherwise it is a bugger to get the flexy into the hole and the cap won't turn on top of the flexy when you go to screw it onto the threaded coupler.

    If you want it really secure fit then pull more flexy thru the hole in the end cap so that the amount of flexy in a loose state pulled through exceeds by a couple of coils the length needed for the flexy to touch the stops half way down the coupler as shown.Then when you screw on the end cap the flexy will be squeezed down it very slight expands the flexy inside the coupler.

    I used to do this to all the connections but now I just pull about 3 coils through and leave it at that.
    I have done dozens of these and have never had one fall off.

    flexyjunction.jpg
    Attached Images Attached Images

  6. #110
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    Quote Originally Posted by node105 View Post
    As you are thinking, the bell mouth does not necessarily need to be turned onto the inlet tubing itself, it can be a projection/extension piece added to the inlet opening.
    Think of it like half a curtain ring /torus
    This approach is found in inlets in carburettor air filter housings

    Router round over bit and MDF with a hole in it is an option.

    For a 6" BMH the minimum roundover should be 1.5" (38 mm) but to get the full round over you need MDF that is at least that thick plus you need to be able to connect the BMH to ducting so you need extra MDF to allow for this,
    For the MDF Hoods I made up a 3 x 18mm (54 mm) MDF sandwich which left 16 mm to make the connection to a PVC fitting.

    Of course in some cases you may not have 38 mm of space to play with. In that case put as much round over as you can.
    You can put more rounding over if you like but that makes it even bigger/thicker.

    The effort needed to make the sandwich and cutting/turning the holes (i.e. MDF dust - Yuck) is why I have gone for the heat formed PVC method.

  7. #111
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    I was going to start a new thread on this but the process is very similar to BMHs so I though it would sit OK in this thread.

    The is a follow up to a discussion in Fletty's shed thread about making gates using PVC flanges.

    I've been slowly making rocker style gates gates for the mens shed over the last couple of months.

    The rocker style gates in my shed are all glued PVC and they work well.
    At the mens shed we had a heap of 3mm thick Al plate (old Hospital signs) so we decided to make gates out of that.
    Just gluing the PVC stubs to the Al has not proved strong enough for the rougher than necessary handling imposed on the gates by shed members so I had to dismantle them and remake them using 4 Al brackets to hold the PVC pipe to the Al gate body. One set of 4 gates is screwed and epoxied together while another set of 4 has the Al brackets TIG welded onto the Al body of the gate and the PVC is screwed and epoxied to to the brackets.
    All in all very time consuming.

    In Fletty's thread he uses MDF for the gate body and a floor waste flange like this one to connect the MDT to the PVC pipe.
    Flange.jpg

    The 6" ones cost $9 so for one gate we'd need 2 flanges, and seeing as I have to make up at least 5 more gates thats $90, and being a cheapskate I'm not prepared to pay this especially when I reckon I can make my own in the same way that BMHs are made.
    These flanges come in very handy for lots of things on dust management systems so I thought it would be worth my while to put some time into the setup.

    Firstly the former, turned up from a very scungy block of tuart I had laying behind the shed - it was the only thing I had on hand that was close to big enough.
    It actually wasn't quite big enough in one dimension - hence the black crappy looking bit of shoulder at the base.

    The former itself is very similar to a narrow radius BMH but includes a small shoulder starting about 50 mm from the base.
    The profile is sort of described by the thick red line.
    The shoulder expands the ducting so that it will fit over regular 6" PVC ducting.
    Initially I had the shoulder at the dotted red line on the former but pushing the hot ducting for nearly 100 mm along the raised shoulder proved difficult (greater friction) so I cut the shoulder back to the position shown on the picture.
    Former.jpg

    Then its the usual lathe running slowly. hot air gun on, and crank in the tail stock.
    It takes more effort and concentration than forming a plain BMH because; there's more friction, more area to keep hot, and keeping the heat even is tricky and if one is not careful a hot spot can develop and the PVC will deform.
    I reckon it takes about twice as long to make them. I was thinking of making a set of formers for BMHs that use this approach i.e. they would then become female BMHS that slip on over a regular piece of ducting but I don't think its worth the effort.

    Anyway a couple of trials and here we are.
    You can just see how the pipe flare slightly just before the parting line on the picture
    While the formed flange is on the former the lathe can be spun up and the outer edge of the flange flare can be tidied up with a turning tool, and the flange parted from the rest of the pipe with a standard 2mm parting tool.
    Remove the two pieces and put the longer bit back on and keep heating and cranking.
    Method.jpg

    The next two blast gates for the mens shed are conventional sliders so here we are 4 flanges ready to go.
    As soon as the flange comes off the former I push it onto a piece of ducting other wise over a few minutes it shrinks so much that it will not go onto a standard piece of ducting.
    The ducting holds it to size while it settles and cools and It can even be used directly on the gates.
    The flange finishes up as a very tight fit but that's Ok, it can be knocked on/off 6" ducting easily enough with a wooden mallet.
    It probably won't even need any glue!

    4flanges.jpg

    Heres the first one I made where it developed a hot spot.
    Wrinkle.jpg

    This one is probably the best one
    Flangeb.jpg

    Ideally the flanges should be dead flat but its the piece of ducting that dos through the flange and into a hole in the gate body that does the sealing. The flange really only provides mechanical support.
    If there is a wrinkle or two it can be plugged with a bit of silicone or gap filler of some kind.

    I worked out, from go to 4 flanges took me 4 hours - that's $9/hour - a lot better than my usual rate of $5/hr AND I can now crank out these flanges as needed.

  8. #112
    Join Date
    Feb 2016
    Location
    Canberra
    Posts
    5,124

    Default

    Could you pre-warm them in the oven?

    Perhaps to half or 60% of the forming temperature?

  9. #113
    Join Date
    Jun 2005
    Location
    Helensburgh
    Posts
    7,696

    Default

    Hot oil would be the way to go.
    CHRIS

  10. #114
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    Quote Originally Posted by woodPixel View Post
    Could you pre-warm them in the oven?
    Perhaps to half or 60% of the forming temperature?
    Yeah I've thought of that but the section of PVC that is being pushed has to be cool or cold to remain stiff enough to push on.
    If not it will deform.
    I do use the hot air gun to preheat the former and the end of the PVC that is to be shaped

    I also tried making the flanges using 2 pieces of PVC.
    One short piece to be the flange, and a longer piece to act as the pusher.
    A in the picture shows the pusher method.
    However the contact point between the two and especially on the flange piece warped and bulged so I gave this away for method B.
    Once the flange os formed I then part the flange from the rest with a parting tool.

    One of the problems is knowing when the PVC is hot and evenly heated enough to start cranking on the tail stock.
    If the PVC is unevenly heated it may bulge in the wrong places and deform.
    What I have been doing is applying pressure with the tailstock which produces creaks and groans from the PVC sliding on the former.
    I then continue to apply heat until the creaks and groans stop.

    I just realised I might be able to use an IR thermometer to monitor the temp even while the PVC is turning.
    Screen Shot 2017-02-09 at 6.37.02 AM.png

  11. #115
    Join Date
    Aug 2007
    Location
    Saskatoon, SK, Canada.
    Posts
    1,436

    Default

    Bob any idea how hot the PVC needs to get to be formable? Chris's suggestion of the hot oil might be doable using a crock pot / slow cooker to warm the end, if about 100C would help? Then you could have one pipe warming while forming another with the heat gun without the need to monitor a pot of oil on a stove or hot plate. Chris do you know?

    Pete

  12. #116
    Join Date
    Mar 2005
    Location
    Camden, NSW
    Age
    74
    Posts
    3,576

    Default

    PVC becomes plastic and deformable at 92C so hot water or oil should work? Oil might be preferable though because of its lubricating properties?
    a rock is an obsolete tool ......... until you don’t have a hammer!

  13. #117
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    Quote Originally Posted by QC Inspector View Post
    Bob any idea how hot the PVC needs to get to be formable? Chris's suggestion of the hot oil might be doable using a crock pot / slow cooker to warm the end, if about 100C would help? Then you could have one pipe warming while forming another with the heat gun without the need to monitor a pot of oil on a stove or hot plate. Chris do you know?
    Pete
    PVC starts to soften at 80ºC and melts anywhere from 100 to 260C depending on what additives are used.
    It starts decomposing at ~140C which is usually before it melts releasing HCL gas which is pretty nasty.
    The decomposition process is also autocatalytic - i.e. once started if not cooled immediately it self propagates.

    PVC pipe has anti softening agents (metals like calcium and tin, they used to use lead so watch out for old dark grey PVC) added so it doesn't soften as much at lower temperatures or melt at too low a temperature.
    So even though it starts to get soft at 80C it needs to be much hotter than this to enable it to be reformed.
    For example 100C (boiling water) is not hot enough to work PVC pipe - I've tried it a few times..
    So ideally you want to keep it lower than decomposition temperature (140C) but soft enough to work.
    You also don't want it really soft or it will bulge, droop and flop all over the place.

    I've used hot oil a few times and found it a bit messy.
    Thats why I like the lathe and hot air gun.
    It works a treat on small areas like BMH and should be OK for flanges once I get a bit of practice.
    It will also be a lot quicker than waiting for a pot of oil to heat up, and then cool down so it can be put away..
    Last edited by BobL; 16th August 2020 at 10:03 AM.

  14. #118
    Join Date
    Sep 2005
    Location
    Perth
    Age
    52
    Posts
    143

    Default

    Hey Guys

    I have just finished plumbing up all of my 6 inch ducting and I am now in the process of opening the ports on all of my machines.
    The first on I did was my Carbatec 15" thicknesser. It works great with a 6" outlet, BUT the machine is now REALLY BLOODY LOUD!!!!!!
    I had a visitor at my place who stays regularly so they are used to the noise in my shed. The day I first tested my thicknesser she came out asking me what all the racket was.
    I'm a bit concerned about the noise, the neighbors are going to get a bit upset i think.

  15. #119
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    27,756

    Default

    Quote Originally Posted by legin View Post
    Hey Guys

    I have just finished plumbing up all of my 6 inch ducting and I am now in the process of opening the ports on all of my machines.
    The first on I did was my Carbatec 15" thicknesser. It works great with a 6" outlet, BUT the machine is now REALLY BLOODY LOUD!!!!!!
    I had a visitor at my place who stays regularly so they are used to the noise in my shed. The day I first tested my thicknesser she came out asking me what all the racket was.
    I'm a bit concerned about the noise, the neighbors are going to get a bit upset i think.
    Good to hear its working!

    Can you temporarily restore the original ducting and have you got a mobile phone app and can you measure a before and after noise level.
    I'd really like to know what this is.
    On the 12" thicknesser at the mens shed and on my 10" my combo machine it made no difference.

    It might be resonating with the ducting = how about a picture of the setup?
    It might be possible to reduce the resonance by changing the length or ducting or adding an elbow into the line.

    Cheers

  16. #120
    Join Date
    Sep 2005
    Location
    Perth
    Age
    52
    Posts
    143

    Default

    Cheers Bob

    When I get back from work next week I will restore it to 4" and see if it makes a difference. I can put a reducer on it and try it with 4"
    I ended up using the old chute and moulded the 6" pipe on to it. It then goes into a wide 90 and a short run of flexi up to another 90 and then down the main trunk.
    I did think about making the chute go straight up from the top plate but I like the rollers for my stock when I am thicknessing.
    I didnt even think of a phone app decibel reader. Ill get onto that.






    Quote Originally Posted by BobL View Post
    Good to hear its working!

    Can you temporarily restore the original ducting and have you got a mobile phone app and can you measure a before and after noise level.
    I'd really like to know what this is.
    On the 12" thicknesser at the mens shed and on my 10" my combo machine it made no difference.

    It might be resonating with the ducting = how about a picture of the setup?
    It might be possible to reduce the resonance by changing the length or ducting or adding an elbow into the line.

    Cheers

Page 8 of 17 FirstFirst ... 345678910111213 ... LastLast

Similar Threads

  1. Advice on opening up machine ports
    By DoctorBobski in forum DUST EXTRACTION
    Replies: 8
    Last Post: 17th August 2014, 02:36 PM
  2. Contractor saw dust extraction - do I need air ports
    By Arron in forum DUST EXTRACTION
    Replies: 8
    Last Post: 13th October 2011, 11:41 AM
  3. improving a lathe cabinet
    By new_guy90 in forum WELDING
    Replies: 11
    Last Post: 3rd November 2010, 07:39 PM
  4. Triton dust ports
    By Hamish Lonsdale in forum TRITON / GMC
    Replies: 3
    Last Post: 30th May 2008, 02:15 PM
  5. dust bin ports may be to small
    By la Huerta in forum DUST EXTRACTION
    Replies: 3
    Last Post: 22nd July 2005, 08:02 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •