Blast Gate Plans

[Jerry Roy]

Boy, do I ever hope I'm doing this right? I can't seem to find the correct way to enter a new post or where to enter it!!!!
Sooooo here goes!!

I would like plans, pictures, specs, materials to use, how to, (and anything else I can get on this subject)on how to make my own blast gates.

I will look forward to your replies,
Thanx,
J.Roy

[Myk Rian]

I know a fellow that makes them out of MDF. Perhaps he'll catch this thread and reply.

[Jim O'Dell]

Not sure I was the fellow but here is a thread I did on building mine. http://www.sawmillcreek.org/showthre...NG+BLAST+GATES I don't know why searching for this is so hard, but I struggle to find this everytime I look for it. Jim.

[Mitchell Andrus]

Welcome Jerry. Here's a thread that may give you a few ideas:

http://www.sawmillcreek.org/showthre...ght=blast+gate
.

[Alan Schaffter]

There is no right or wrong way to make a blast gate, but some features make some gates better than others. Here is what I would consider essential for any gate:

1. Self cleaning- slide goes all the way through
2. When closed seals well and does not leak.
3. Is sized to fit your ducting and flex hose
4. Is easy to operate- smooth sliding action, even when DC is operating
5. Is easy and inexpensive to make

Here is the construction drawing for my gates which were made from scrap MDF and laminate and PVC. I built 12 of them at the same time, production style. All my gates started out this way:





These are designed for PVC S&D ducting but you can easily select different size and type of inlet and outlet material. An article how to build these will be in an upcoming issue of American Woodworker Magazine.

There are other features and options for more advanced blast gates:

1. Remote cable or linkage to operate gates in hard to reach locations
2. Sensor or switch mounted on gate that starts and stops the DC (I don't like this one)
3. Fully automatic gates triggered by current sensors at outlets powering the machine (what I have)

I converted all my gates to fully automatic operation. Here are pics of my prototype autogate and a less photogenic shot of one of the operational autogates mounted on the underfloor ducting leading to my tablesaw:





I thought allot about the gates and DC operation- starting the DC was not the issue- I had ample 3 wire control stations around the shop- but I would often forget to open or close a gate, or more often, since I am basically lazy just would not do it. So I wired current sensor switches near each tool power outlet. When a machine is turned on or off the switch operates a solenoid air valve, which ports 15 psi shop air to a bi-directional pneumatic cylinder mounted on the gate body and which operates the slide. When any gate is operated the DC starts and stays running until I manually turn it off - I intentionally designed it this way. Each gate also has its own manual control station. If you go to the American Woodworker website there is a video tour of my DC with demo of an autogate in action.

[Mark Bosse]

Do you have a source for the pneumatic parts? I am totally confused by the Parker catalog.

[Alan Schaffter]

Do you have a source for the pneumatic parts? I am totally confused by the Parker catalog.

The quick answer is Ebay.

The cylinders were bi-directional (powered open/powered closed) by Bimba (major manufacturer)- unless you want to mess with linkages you need cylinders with a stroke 1" longer than the size of your gate- i.e. 6" gate = 7" stroke. Things you need to consider- port size/thread size, mounting, and bore- you can go with a small bore. I watched and waited so got new ones really cheap (< $10 ea.)

Pnuematic valves were by SMC (major manufacturer). You need to research online because there are many, many types (SMC has allot of info on their site). For bi-directional action you need 5-port valves(1 pressure in, 2 pressure outs, 2 vents). The solenoids come in 24VDC, 110VAC, 220VAC, etc. I used 24VDC so I could control them directly from the low amperage current switches without additional relays. Some come as a small all-in-one valve/ports/solenoid (3rd pic); others have a separate port block. Those often come stacked side-by-side in large manifolds with openings on each side.(1st pic) Many of mine came like that- I disassembled the manifold and made plastic cheek plates for each side and added a pressure input port to one side.(2nd pic) (check out my video)



If your gates slide smoothly, they will only need 10-20 psi to operate, but even at that low pressure will be like guillotines and likely tear themselves apart without flow restrictors- same pressure, slower actuation. One of my manifolds came with those so I was set. My solenoid valves averaged $5 - $7.

Good luck.

[Wes Billups]

Alan, everytime I see pictures of your shop I'm in awe. Have you ever been contacted by any of the magazines to do an article(s) on your shop? They could fill an entire years worth just picking different features you've built into your shop.

Another question, do you have a shop tour posted anywhere? I remember seeing many posts about your mitersaw bench and shop door build but can't seem to find them.

Thanks,
Wes

[Alan Schaffter]

Alan, everytime I see pictures of your shop I'm in awe. Have you ever been contacted by any of the magazines to do an article(s) on your shop? They could fill an entire years worth just picking different features you've built into your shop.

Another question, do you have a shop tour posted anywhere? I remember seeing many posts about your mitersaw bench and shop door build but can't seem to find them.

Thanks,
Wes

Thanks!

First answer- after I won the WoodCentral/Woodcraft Top Shops Contest last year, Woodcraft magazine wanted to do a six page spread on it. I wanted to limit coverage of some features and "take-aways" because they are material for potential Shop Tips and Articles. Jim Harrold, the editor didn't want any restrictions, so I declined. Since I am retired I can use extra cash to support my hobby. Since their staff was going to write and photograph the article they were only going to pay me $200. Just one tip is typically worth $100 to $150 and an article, even for a rookie, pays $200-$300 per page. It was a wise decision since I have since sold a number of tips to various WW mags and had a two-part article published in American Woodworker in December. I have a number of other tips and articles in all stages of development (a few already under contract!). FYI, I have had more tips rejected than published, but I did get one in FWW! That was probably more than you wanted to know.

A few years ago I started a website but changed ISP's and never moved or updated it. I keep my photos on NC Woodworker dot net. I don't know if guests can view it, however. My gallery is under user name Alan in Little Washington.

My goal is to progress from working "on" my shop to working "in" my shop and have an article published about a piece of furniture I designed and built.

[Boyd Gathwright]

Hi, This thread may help you.

http://www.sawmillcreek.org/showthread.php?t=7761

.... Wish you well on your venture.

[Lee Schierer]

Blast gates are simple. Take two pieces of wood (any wood will work), about 1" per side bigger than the pipe. Bore a hole in them that fits the OD of the pipes in question. Then take a piece of Lexan with the film still on the surfaces and the same width and 2" longer in one dimension than the two pieces of wood. Sandwich the lexan between the two pieces of wood so it is flush on three sides, then trace the hole onto the covering. Remove the piece of lexan and extend lines from the edges of the circle to the top of the piece in the long direction to make a "U". Then cut the U with a band saw going about 1/4" outside the U-shaped line. Reassemble the sandwich with the two pieces of wood sandwiching the outside of the U-shaped cut out. Hold these three pieces in place with four wood screws through the corners. Trim off all of the lexan sticking out the top of the sandwich. Peel the covering material off the tongue of the U and slip it into the slot in your sandwich. It should slide in. Now you have one blast gate. You can attach it to your duct work with silicone sealant.