6" Blast Gate for PVC?

[Jim O'Dell]

If you make your own, getting the holes cut is the hardest thing. I made a circle cutting jig for my router to do mine. Tweaked the pivot hole using scrap OSB until I had a really tight fit on the pipe. This took the longest. Then when using it, be sure to anchor the body pieces down to a work surface. I used screws through the corners as you need to be able to "bolt" the piece together. In fact, I anchored the slide in place and cut all three pieces at the same time. Be sure to put 3 screws in the part you are cutting out to keep it from flopping around when you cut through a layer. Keeps it from lodging against the bit and side of the cut creating problems. It also makes sure your pivot point doesn't move. Learning that tool a couple tries. The most time consuming part time wise was tweaking the hole that is cut to get the right size for the pipe. After that you can crank out 10 gates in an hour, plus time for assembly. Jim.

[Alan Schaffter]

If you make your own, getting the holes cut is the hardest thing. Jim.

It is easy if you make the gate using my method. The holes don't need to be precise at all and can be cut with a jig saw, or if you laminate the inside faces, you can even use a bandsaw and an access cut. All you need is far-from-perfect, rough holes for the inlet and outlet fittings- the key is to glue them in place with polyurethane glue (Gorilla Glue, PL, etc.). Poly glue will expand to fill any gaps and makes a tight seal.

What I do is cut the holes, laminate the faces with small, solid pieces of high pressure laminate (Formica, etc.). I get free scraps from my local counter shop and use water based laminate adhesive to attach it. If you don't want to laminate the faces you don't need to, it just makes slide move and seal much better, IMHO. Then I glue the fittings in the holes with the poly glue, making sure they bottom out against the back of the laminate at the bottom of the hole. If you don't laminate the gate faces, you must make sure the inlet/outlet fittings don't protrude past the inside faces of the gate. Since I laminate them, once the poly glue has set, I drill an access hole in the laminate and open it up using a hand-held router or my router table and a flush trim bit. That yields a perfect hole and perfect gate face since the bit's bearing rides on the inside of the fitting.

Gate parts. PVC inlet and outlet (a short piece of pipe and 1/2 of a coupling), MDF gate body halves- holes were cut with a jig saw, small strips of laminate are used to hold the gate halves together, the slide is made from the two large pieces of laminate which are bonded together back to back. I cover the MDF with the square pieces of laminate and glue in the inlet/outlets before making the hole in the laminate:



I drill a small access hole, then use a flush trim bit to open the hole in the laminate. This results in a near perfect hole since the bearing rides on the inside of the fitting, not the MDF:



I use double stick tape to hold the gate slide to one half of the gate and make the hole in the slide the same way.



I apply laminate adhesive to two edges of the gate halves and the laminate side pieces. I add (blue) tape spacers to the slide.



I clamp the gate halves and slide together, then apply the edge pieces of laminate to hold everything together. I pull out the slide, remove the blue tape, and I'm done. This method is quick, easy and durable- have you ever tried to remove laminate from MDF- the MDF fails before the adhesive.



I use a simple little cradle made from a piece of 2 X 4 with a "V" slot cut in the top and mounted to my miter gauge, to safely cut fittings and pipe on my tablesaw:



Blade height is set so it barely cuts the bottom of the pipe/fitting. I feed the sled until it is centered over the turning blade, then I rotate the pipe/fitting until it is cut through- safe and simple.

[Bruce Seidner]

That is a great tutorial Alan. Thank you.

Bruce

[Dan Case LR]

Interesting technique, using the laminate to hold the two halves together. I have, however, seen laminate let loose of the edge profile of saw-cut MDF, in cases where the cut edge was a little too "fuzzy" or any less than a perfectly flat, square surface. Oof course, we wouldn't have imperfect surfaces, right?

D.

[Alan Schaffter]

Interesting technique, using the laminate to hold the two halves together. I have, however, seen laminate let loose of the edge profile of saw-cut MDF, in cases where the cut edge was a little too "fuzzy" or any less than a perfectly flat, square surface. Oof course, we wouldn't have imperfect surfaces, right?

D.

I cut the MDF gate body parts with a WWII blade on my tablesaw, but other than that, the edges received no special treatment. Per product recommendations I made sure I applied two coats of water-based laminate adhesive to the edges of the MDF and the laminate side strips, and waited until everything was completely dry before assembly. After seven years I have had no failures nor the slightest delamination. When you think about it, there really isn't much stress on the gates.

[Kevin W Johnson]

+1 on the clearvue gates--http://www.clearvuecyclones.com/11-supporting-products. The plastic they use seems a lot stronger than that black plastic ABS stuff that seems to be everywhere. I also like that I can disassemble these and surface mount these--I've used them as connections for widening the DC connection on my jointer and implementing a better solution for my TS.

I was prepared to order 3 of these, then i discovered the shipping was another $18 and lost interest.

[Paul Wunder]

Kevin,

Yup, shipping costs have doubled since I last bought my new gates. I paid $90 for 6 gates plus $15 shipping. $18 does seem high for three gates. Have you spoken to them?

Paul

[David Hostetler]

I bought my gates, they are 4" and not 6" but I would imagine their 6" models are just as nice. I went with the ones from Lee Valley and they have been completely trouble free...

FWIW, they are kind of spendy, if you have the time and inclination, I think it would be kind of cool to make your own...

http://www.leevalley.com/en/wood/page.aspx?p=51506&cat=1,42401,62597

They are a bit spendy like I mentioned. $16.15 each for quantities of 4+ for the 6" models... But if you have the budget, and want to use the time for something else... They are very well made...

[Dan Case LR]

I bought my gates, they are 4" and not 6" but I would imagine their 6" models are just as nice. I went with the ones from Lee Valley and they have been completely trouble free...

FWIW, they are kind of spendy, if you have the time and inclination, I think it would be kind of cool to make your own...

Thanks, David. Yes, Lee Valley is spendy, but when compared to other aluminum gates that aren't self-cleaning, they aren't so bad.

I agree it would be cool to make my own, and it would be quite economical IF I had all the materials sitting around the shop. However, if I've got to go buy materials AND spend my time, the advantage quickly fades. All things considered, I think I'd rather buy my blast gates and spend my shop time making a new bench rather than making blast gates. Lee Valley is a definite contender.

Thanks!

D.

[Anthony Whitesell]

I don't have a lot of time and I don't have a lot of money. But I do have more time than I have money. But if buying the materials costs more than buying pre-made gates. The flip side is if you make your own, you can always make more. They way companies put out and discontinue products nowadays. The gates you get know may not be available later. The distant last thing to consider is if you are going to automate the gates. Now or later. Building them yourself, you can design them to accept the drive later. If you buy them, you'll need to modify them later (if possible).

[Scott Wigginton]

I went with http://www.blastgateco.com/Blast-Gates.php since I was looking for a mix of 4" and 6". They fit well in my S&D pipe

[Chris Parks]

For an alternative take on blast gates http://www.sawmillcreek.org/showthre...ght=blast+gate

[Dave Kennedy]

I know this is an old thread, but I found it very useful and along with other information from Alan gathered a materials and dimensions list. His article in American Woodworker June/July 2010, #148 had the info for a 4" gate. I extrapolated that to 6" gate dimensions. I thought others might find this useful.

Qty	Material	4” Gate Rough	4” Gate Final	6” Gate Rough	6” Gate Final	Description
2	½” MDF	6” x 6”	6” x 6”	8” x 8”	8” x 8”	Gate body pieces
2	Laminate	6 ¼” x 6 ¼”	6” x 6”	8 ¼” x 8 ¼”	8” x 8”	Gate body faces
2	Laminate	7” x 14”	5 15/16” x 13”	9” x 18”	7 15/16” x 17”	Blade
2	Laminate	1 ½” x 6 ½”	1” x 6”	1 ½” x 8 ½”	1” x 8”	Sides (trim flush at end)

[Robert Engel]

I purchased all my gates and flex from PennStateIndustries. They fit right inside thinwall pvc.

[Joe O'Leary]

Thanks, Dave. Big help.