working with duct board

[chrashley]

I was wondering if anyone had a good manual or fieldbook for making all sorts of duct board configurations. i.e. ninetys, fourty-fives, off-sets, reductions, both horizontal and vertical.

I know the general idea for getting these to work but getting them exact is giving me some trouble.

Thanks for the help.

[erair]

THERE ARE ALOT OF HANDY TOOLS FOR DUCT BOARD A GOOD TOOL FOR MAKING ELBOWS 45'S AND OFFSETS IS SOLD IN MOST SUPPLY HOUSES. IT IS AN ALUMINUM PIECE OF METAL WELDED TO A 15 DEGREE AND A 22 DEGREE ANGLE. THE NAME ESCAPES ME RIGHT NOW BUT i'LL ASK OUR DUCT MAN AND GET BACK TO YOU.

[airconman]

a knife and a hammer is good... when ya rip it out!!!

[chrashley]

The tools are not a problem. I was more concerned with having a good set of field notes to use when I need to make duct board ninetys or whatever configuration I needed at the time.

Sometimes I go into a house and the plenum can't go straight up through the trusses. So I have to off-set it and usually it's a guessing game for how far to cut it and how to get the angles looking good. Bottom line is it usually takes forever and alot of times ends up looking somewhat like crap.

So somebody please get me directions to a website or a book so I can get my shit together.

Thanks

[targetman]

Try this http://www.knauffiberglass.com/index...aseStudiesList

[ct2]

http://www.jm.com/insulation/technic...micro-aire.pdf

[Dof3]

Duhhhh, a hammer and knife so you can rip it out. Nice of you to post a helpful hint, airconman. chrashley, Amcraft,Glassmaster and Malco make tools for ductboard and also have layout instructions. LOL

[lonnirat]

Originally posted by airconman
a knife and a hammer is good... when ya rip it out!!!

Still laughing.

[chrashley]

OK either I'm completely stupid and not seeing that you guys are giving me the answer to my querry, or I'm not asking the right question because it seems like I'm not getting the right answers.

I know how to put ductboard together. I know how to joint sections of the same size and alll that crap. What I want to know is this...

If I'm using say 20 x 8 (inside measurements) fiberglass duct and I need to off-set that duct 10 inches how do I do it. What angles, what measurements do I use.

Also, If I'm using 20 x 8 duct again and I need to make a flat 90. How do I do it.

Or a horizontal 90...etc...etc.

Dof3-I think you understood my question but I got nowhere with my search with the info you gave me. Sorry for being so dense here.

I appreciate all the help so far. Thanks.

[chrashley]

PLEASE...somebody help me!!!

Maybe you don't have a book. Tell me how YOU do it.

[Dof3]

OK Let me see if I can explain it. If you have to offset 10" you need to use a saw guide or the angle guide made by Amcraft. Use the 15 degree side and double your mark length. For 10" you should measure 20" and make a 15 degree mark. Now scribe the foil liner with a ductboard knife and then on your flat sides use a cutoff tool to cut the male female ends. You don't need to cut male/female on the short side[no angle side]. Now pull your pieces apart and flip them around to your angles. Tape across them to hold them together then tape with the cut.For a 90 degree elbow,lay your duct work on a table flat. Make your first mark and then use the guide to make a 22 1/2 degree angle on it. Move to your next mark and make another 22 1/2 degree angle opposite the first one. Scride the foil and then cut the male/female with your cutoff tool. I have made all of these angles using a 12" speed square and also a saw guide. But, the angle guide is much easier to use.I got some of the books I use from NAIMA.

[dec]

dont use much duct board any more but when I did I use to carry a little blue book in my pocket. It was just filled with all my little notes on short cuts for making fittings in sheetmetal and ductboard. Dam I wish I knew what happened to that book and being its one that I made my self over the yaers , its not like I can just go out there and buy a new one. Now from what I have heard lately , you dont cut the duct board with the same cutter knives that you use to 20 years ago. Last time I looked at a little flyer stuff in the duct board box it showed differant measurments and differant colored cutters. Its funny the duct board manufactures dont put a printable instruction manuel on their web site.

[Edited by dec on 05-15-2005 at 11:26 AM]

[chrashley]

thanks Dof3, I think that is what I'm looking for. Now to try it out to see if I really understand...

[Dof3]

It just takes a little practice. When you get it you'll know. Sometimes the 90's are a little off, just take your time.

[chrashley]

Dude...that's it. I did it today and it worked like a champ. No more guessing and estimating for me. I hella appreciate it!!!

[Dof3]

Well let me tell you this. If I can do it anybody can!!