jig plate
11-13-2008, 07:50 PM
#13
0.5 BAR
Join Date: Jul 2008
Posts: 132
Re: jig plate
I have a 1" thick by 4" wide by 2' long piece of aluminum that I use for keeping flanges flat.
It has no holes in it. I clamp the flange to it. Clamps work with any flange- if you use the right clamps they also tend to be less "in the way" of where I am trying to weld. The aluminum conducts heat well and means I can do a lot of flange welding without overheating the flange. It also means I'm not dragging a piece of steel that big (it would be much heavier) around the bench as I move things to get at the welds. Also I use stainless flanges- it's minor but all of that contact with carbon steel isn't ideal.
My jigs are ------ wooden. Yup. Wood.
I only use them for fitup and tacking and they last a long time. I might get fancy and start making aluminum ones since it's a real breeze to weld with the new welder, but wood seems to work KO.
I have made about 15 header off that jig so far.
I prefer to fit everything up, then cut the runners off one by one and weld them up, then weld them back on.
I always wonder if I had a super rigid jig, and I welded everything up solid under a lot of restraint, there was a possibility of having locked in stresses due to distortion.
The wooden jigs acre actualy pretty light and stiff and fast/cheap to make.
edit: Here you can see aforemention bigass piece of aluminum, being it very versatile self:
It has no holes in it. I clamp the flange to it. Clamps work with any flange- if you use the right clamps they also tend to be less "in the way" of where I am trying to weld. The aluminum conducts heat well and means I can do a lot of flange welding without overheating the flange. It also means I'm not dragging a piece of steel that big (it would be much heavier) around the bench as I move things to get at the welds. Also I use stainless flanges- it's minor but all of that contact with carbon steel isn't ideal.
My jigs are ------ wooden. Yup. Wood.
I only use them for fitup and tacking and they last a long time. I might get fancy and start making aluminum ones since it's a real breeze to weld with the new welder, but wood seems to work KO.
I have made about 15 header off that jig so far.
I prefer to fit everything up, then cut the runners off one by one and weld them up, then weld them back on.
I always wonder if I had a super rigid jig, and I welded everything up solid under a lot of restraint, there was a possibility of having locked in stresses due to distortion.
The wooden jigs acre actualy pretty light and stiff and fast/cheap to make.
edit: Here you can see aforemention bigass piece of aluminum, being it very versatile self:
11-14-2008, 09:48 AM
#17
0.0 BAR
Thread Starter
Join Date: Oct 2003
Posts: 0
Re: jig plate
Originally Posted by jagojon3
LoKOs like there's more room with the vise grips than there would be with bolts in there actually.
11-14-2008, 02:56 PM
#19
0.5 BAR
Join Date: Jul 2008
Posts: 132
Re: jig plate
Yeah the wooden jigs are extra HMT foodstamp material eh? And to think I made that way before I joined HMT. Must be in my blood. 
Some of my flanges are threaded and some arent. Some cannot be.
It depends on the application and turbine housing. On some turbos the turbine housing is threaded and you need to install studs in the housing (there is no room for nuts on the backside of the housing- a good example is a holset HY35 or HE351, which is as very common turbo for the volvo guys at least.)
The head flanges are never threaded obviously.
I can see some merit to having plates with holes, don't get me wrong- i'm not syaing it is a bad idea and doesn't work fine, but for me there is generally lots of room with the vice grips there, and I have 8 sets of vise grips that stay permantently set to clamp a 3/8" flange on the 1" aluminum piece, so it's extremely fast to clamp up. Stick the flange on, snap,snap,snap, weld 'er up. No wrenching no hardware. Just a different approach I suppose.
Some of my flanges are threaded and some arent. Some cannot be.
It depends on the application and turbine housing. On some turbos the turbine housing is threaded and you need to install studs in the housing (there is no room for nuts on the backside of the housing- a good example is a holset HY35 or HE351, which is as very common turbo for the volvo guys at least.)
The head flanges are never threaded obviously.
I can see some merit to having plates with holes, don't get me wrong- i'm not syaing it is a bad idea and doesn't work fine, but for me there is generally lots of room with the vice grips there, and I have 8 sets of vise grips that stay permantently set to clamp a 3/8" flange on the 1" aluminum piece, so it's extremely fast to clamp up. Stick the flange on, snap,snap,snap, weld 'er up. No wrenching no hardware. Just a different approach I suppose.
