So much simpler than that Steve. If tube is squared up and work surface is level & if fit up of fins to tube aren't too loose or too tight. gravity does all the work. spacers are whatever scrap plate is lying around that's also the correct thickness and flat, just laid loosen the plate. I used three separate.25" thick aluminum 1" wide by 4" long. Just laid in loose around the tube. They are only in for the three tacks and then removed for the short stitch welds, keep each stich short and you will see no warp,unless you try to weld the complete circumference in one pass. Then stitch the tacks on the fin bottom, only three one inch tacks are plenty for strength. Then clean up the spatter and repeat on the next fin. Remember your working from top cylinder down, welds are out of sight when the completed cylinder is flipped to the upright position; get the first fin right and the rest just tag along. Clamp the first fin to the work surface with two C clamps and get the tube centered and hold it down with a few pounds of weight on top while tacking, then remove it the weight from the tube & complete the three , on inch stitch's. Not much heat so little chance of warp. Use too much heat and you get warp, not matter what else you do.
The first fin is used as a clamp surface for the C clamps, but the clamps must be moved outside of the fin diameter to make room for the next fin, so clamping is done by using a couple of "thin" strips of steel to overlap the fin enough to securely hold for the rest of the welding process on the complete cylinder.
It took twice as long to explain this than it does to actually do it Welding is not like machining or cabinet making. fitting is important, but fine tolerances actual hamper the strength of a good wire or stick welds. Most jobs a 1/16" fit up allows great penetration on 10 gauge flat sheet to tube 1/32" on 14 ga. thinner material closer to butt up. Lot's of nuances for pro's but not needed here.
All the fit up is done prior to welding, none occurs during welding, Position,weld, clean up and space ...repeat till complete. Once the first fin is complete position is achieved my placing the three spacers, around the tube with one end sticking out far enough to grasp for easy removal after the tacking is completed. That's all there is to positioning the plates, quick & easy and nothing to think about except making a good weld which will never happen if you are worrying about fit up during actual welding.
Hope this helps Steve. With a TIG or MIG this is a 10 minute job per cylinder with flux core or stick, cleanup as you go could add 30 minutes or more to the task time and is more about cleanup than welding.
Rick C.
Good fabricators and pipe fitters make the welder and the project.
The first fin is used as a clamp surface for the C clamps, but the clamps must be moved outside of the fin diameter to make room for the next fin, so clamping is done by using a couple of "thin" strips of steel to overlap the fin enough to securely hold for the rest of the welding process on the complete cylinder.
It took twice as long to explain this than it does to actually do it Welding is not like machining or cabinet making. fitting is important, but fine tolerances actual hamper the strength of a good wire or stick welds. Most jobs a 1/16" fit up allows great penetration on 10 gauge flat sheet to tube 1/32" on 14 ga. thinner material closer to butt up. Lot's of nuances for pro's but not needed here.
All the fit up is done prior to welding, none occurs during welding, Position,weld, clean up and space ...repeat till complete. Once the first fin is complete position is achieved my placing the three spacers, around the tube with one end sticking out far enough to grasp for easy removal after the tacking is completed. That's all there is to positioning the plates, quick & easy and nothing to think about except making a good weld which will never happen if you are worrying about fit up during actual welding.
Hope this helps Steve. With a TIG or MIG this is a 10 minute job per cylinder with flux core or stick, cleanup as you go could add 30 minutes or more to the task time and is more about cleanup than welding.
Rick C.
Good fabricators and pipe fitters make the welder and the project.
