Thread: 4" PVC pipe mismatch with commercial blast gates and flex hose

Are you sure you got 100mm and not 90mm? - my local Bunnies mixes the two up all the time. Also 100mm is less than 4" by roughly 3mm(1/8").

I though 100mm nominal pipe was just a bit bigger than 4" fittings anyway, and you had to wrap the fitting with dust tape to get it to fit - then again it may be the other way round, you put the pipe inside the fitting & use tape to build it up.

From this you may gather that I have looked at rigid pipe but have only bought a variety of flexible tube to go with the box of assorted fittings I am collecting

Originally Posted by bsrlee

Are you sure you got 100mm and not 90mm? - my local Bunnies mixes the two up all the time. Also 100mm is less than 4" by roughly 3mm(1/8").

I though 100mm nominal pipe was just a bit bigger than 4" fittings anyway, and you had to wrap the fitting with dust tape to get it to fit - then again it may be the other way round, you put the pipe inside the fitting & use tape to build it up.

From this you may gather that I have looked at rigid pipe but have only bought a variety of flexible tube to go with the box of assorted fittings I am collecting

Def 100mm - it's the fittings from carbatec that seem to be less than 100mm by a few mm !

Check out this thread for some options https://www.woodworkforums.com/f11/co...-solved-28127/

Originally Posted by Fuzzie

Check out this thread for some options https://www.woodworkforums.com/f11/co...-solved-28127/

After finding this link earlier last year, I visited my local Tradelink store armed with the required codes and was informed that they are no longer available. after investigation I was told that it was something to do with changes in Qld plumbing requirements.

I may try another store soon and see what response I get.

100mm pvc is a 'close enough' fit to a blast gate. The fittings (elbows, joiners, etc) are too big. To connect a blast gate to rigid pipe I held the two parts together and drilled a small hole through the pipe into the lip of the gate. I then put a small self taping screw to hold them whilst I ran a bead of latex gap sealer around the join. Once dry it was a perfect air tight fit.

To get a perfect flush fit between gate and pipe, you can't use the cheap plastic gates and pvc pipe. That becomes more the realm of metal ducting and gates. Ergo instead of $5/fitting you are then paying about $80/fitting... for the minimal resistance imposed by using pvc coupled to the cheaper plastic gates vs little/no resistance of a specialised metal system at around a months salary its not too hard a decision! lol

As for the flex hose, that fits quite nicely inside the larger diameter of the elbows/joiners. Just jam it in about 30mm or so the wrap the join with duct tape. So basically all you ned at the end of a pipe run is either an elbow or a straight joiner and your flex hose will fit right in.

Originally Posted by socratous

100mm pvc is a 'close enough' fit to a blast gate. The fittings (elbows, joiners, etc) are too big. To connect a blast gate to rigid pipe I held the two parts together and drilled a small hole through the pipe into the lip of the gate. I then put a small self taping screw to hold them whilst I ran a bead of latex gap sealer around the join. Once dry it was a perfect air tight fit.

To get a perfect flush fit between gate and pipe, you can't use the cheap plastic gates and pvc pipe. That becomes more the realm of metal ducting and gates. Ergo instead of $5/fitting you are then paying about $80/fitting... for the minimal resistance imposed by using pvc coupled to the cheaper plastic gates vs little/no resistance of a specialised metal system at around a months salary its not too hard a decision! lol

As for the flex hose, that fits quite nicely inside the larger diameter of the elbows/joiners. Just jam it in about 30mm or so the wrap the join with duct tape. So basically all you ned at the end of a pipe run is either an elbow or a straight joiner and your flex hose will fit right in.

Cheers - I thought I was doing something wrong - turns out my expectations were highly elevated )

Thanks heaps

Originally Posted by socratous

100mm pvc is a 'close enough' fit to a blast gate. The fittings (elbows, joiners, etc) are too big. To connect a blast gate to rigid pipe I held the two parts together and drilled a small hole through the pipe into the lip of the gate. I then put a small self taping screw to hold them whilst I ran a bead of latex gap sealer around the join. Once dry it was a perfect air tight fit..

I do a similar thing except I just use gaffer tape instead of the sealer. One of the reasons for this is it makes it easier to dismantle and clean the blast gate slots.

To make things even easier I have removed the stops from some of the blast gate doors so that I can remove them completely so that I can slide a thin strip of ally into the slots to clean them in situ.

Originally Posted by Mulgabill

After finding this link earlier last year, I visited my local Tradelink store armed with the required codes and was informed that they are no longer available. after investigation I was told that it was something to do with changes in Qld plumbing requirements.

I may try another store soon and see what response I get.

I would try another store - I bought some of the connectors I listed in the original thread approx October 2010.

If you can't get satisfaction - PM your details to me + how many you require, and I'm sure I can mail them to you.

Regards,
Bob

I have used 100mm PVC in a similar way to Socratus and BobL.

I have a about a 6 metre run of 100mm PVC with 45 degree outlet elbows down the side of my garage and then use a short length of flexible hose to bandsaw, thicknesser, etc. by putting an end cap over the elbows not in use and shifting the hose where needed.

Originally Posted by Bob38S

I would try another store - I bought some of the connectors I listed in the original thread approx October 2010.

If you can't get satisfaction - PM your details to me + how many you require, and I'm sure I can mail them to you.

Regards,
Bob

Cheers Bob! As I said I will try another store near to where I work when I return.
Thanks for the offer!

Take you fittings down to Tradelink and check, they have a black gas pipe that is a snug fit. I can't remember the part number but it was expensive.

Ross

Hi Pell, I have heated up my 100DWV (sewer pipe) using the hot air gun, from memory its 115mm OD and the fittings are right on 120mm OD which are good for me as this goes nicely into 120mm blast gates, but not what u want
I have expanded and contracted it, say 50mm in length to suit whatever I was doing
I'll take some pics tomorrow if I remember for further explanation, don't hit me if i forget tho
I have also taken a slice out the side of a short piece to make a reducer, from memory cut ~6mm and it will go inside and if u put it over the outside u have a gap of about 12mm which u can fill will a slice or silastic or not

Pete

Here's a few pics of some fittings I made to suit 100mm hose.
I heat the pipe with a hot air gun and I either expand or contract the pipe by pushing it over or into a form, the forms are made from the same pipe.
Some suitable turned wood to suit would be better as the forms themselves can deform with the heat. The heating takes a minute or two, I rotate the pipe while heating to a uniform heat until the pipe is flexible but not too floppy, I use welding gloves to protect my hands then I push the soft pipe either over or into the form, I then cool with cold water, the reducing process is probably the trickiest because the pipe can tend to pucker espcially if too hot.

Heat increasing form with a reinforcing piece inside.... heat reducing form, note the lead in on the top edge
Attachment 158655Attachment 158656

A 100mm hose tail and a joiner, (I expanded both ends) note the heat bubbles from just a little too much heat
Attachment 158657Attachment 158658

I have also split a short piece and pushed it inside another short piece to form a hose tail
Attachment 158659Attachment 158660

And a peach/beetroot/??? tin fits nicely inside 100mm hose, add some foam rubber to make it to 120mm, also a vac hose to 120mm if push comes to shove
Attachment 158662Attachment 158661

This 32mm size pipe I reduced down to suit the drop saw, heat up and shoved it into the outlet and a short piece of copper to suit the vac hose
Attachment 158663

I hope this helps


Pete

Hello
I have been following this thread.
Bob I also have bought around 20 adapters, they are common in WA as earthen ware pipes were very common and still exist in older areas. If anyone needs some I can check with the local Tradelink and order some and send them on if that is of any help.
Cheers Gerry