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Firestopper
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I focused on the adjusters for the top clamp. These are used like screw jacks that move the entire top clamp forward and aft to adjust for material thickness and bend radius. Located at each end and rear of the machine. They come from Dreis&Krump with hand wheels and should adjust with little effort. The right one would bind when the machine was assembled so I suspected a bent screw. Both cranks where fabricated and not OEM. The right crank was ok but sloppy while the left crank was made from tubing ,angle iron and a round bar and also sloppy. Both where held in place via roll pin.
The right crank looked better than the left crank, but would bind when rotated.
The left crank was crappy compared to the right, but turned with lite effort, but also had a wobble when rotated.
Disassembled the right jack assembly and confirmed my suspicion of a bent screw shaft.
Luckily, it was only bent on the last section where the crank slid on.
After indicating the screw in the lathe, I cut off the bent section to salvage the remaining shaft.
After facing, a center drilled was used then drilled to 11/16" x 1.250" deep. I also used a 11/16" four flute end mill to create a flat bottom hole. A 3/16"bevel was also turned prior to removing the screw.
I then took a piece of 1" CR round and turned the for a interference fit +.0015". I also beveled the shoulder for welding.
A small propane torch was used to heat the receiving screw bore to eliminate heavy hammering with the brass hammer.
The new sleeve worked well after fully seated leaving a nice area for a root pass for TIG welding.
Heating for pressing also preheated for TIG welding.
Chucked up and turned for the hand wheel design (in my head). Turned .060" to blend in the weld. The Bevel ensured weld remained with zero porosity. The smaller diameter .775" (stepped) will be matched with the new hand wheels for a good hold. I also did the left screw as it too was bent (not as bad) and the the two will be identical and beefier.
Bothe screws are now running true and more robust than original. The hand wheels will be turned from 3" round aluminum I have in the scrap bin. The will turn a hub and bore to match the profile of the screw shafts. The roll pin or set screw will secure to the larger diameter (welded area) while the smaller diameter will provide added stability. I want the feel of a single piece when turning with zero play when adjusting.
The black sharpie lines are where the welds are for reference. I think this was a good solution for salvaging those screws and can be used for other similar applications. I used a total of 5" of 1" CR to fix these screws and saved a lot of time vs turning new ones.
Here you can see the original (smaller) bent ends to the right of the salvaged screws.
And finally the right jack assembly resting where it will be located. I should have plenty of clearance for the hand wheel once assembled.
That all for today, they had us running last night so running on empty.
Thanks for stopping by.
Paco
The right crank looked better than the left crank, but would bind when rotated.
The left crank was crappy compared to the right, but turned with lite effort, but also had a wobble when rotated.
Disassembled the right jack assembly and confirmed my suspicion of a bent screw shaft.
Luckily, it was only bent on the last section where the crank slid on.
After indicating the screw in the lathe, I cut off the bent section to salvage the remaining shaft.
After facing, a center drilled was used then drilled to 11/16" x 1.250" deep. I also used a 11/16" four flute end mill to create a flat bottom hole. A 3/16"bevel was also turned prior to removing the screw.
I then took a piece of 1" CR round and turned the for a interference fit +.0015". I also beveled the shoulder for welding.
A small propane torch was used to heat the receiving screw bore to eliminate heavy hammering with the brass hammer.
The new sleeve worked well after fully seated leaving a nice area for a root pass for TIG welding.
Heating for pressing also preheated for TIG welding.
Chucked up and turned for the hand wheel design (in my head). Turned .060" to blend in the weld. The Bevel ensured weld remained with zero porosity. The smaller diameter .775" (stepped) will be matched with the new hand wheels for a good hold. I also did the left screw as it too was bent (not as bad) and the the two will be identical and beefier.
Bothe screws are now running true and more robust than original. The hand wheels will be turned from 3" round aluminum I have in the scrap bin. The will turn a hub and bore to match the profile of the screw shafts. The roll pin or set screw will secure to the larger diameter (welded area) while the smaller diameter will provide added stability. I want the feel of a single piece when turning with zero play when adjusting.
The black sharpie lines are where the welds are for reference. I think this was a good solution for salvaging those screws and can be used for other similar applications. I used a total of 5" of 1" CR to fix these screws and saved a lot of time vs turning new ones.
Here you can see the original (smaller) bent ends to the right of the salvaged screws.
And finally the right jack assembly resting where it will be located. I should have plenty of clearance for the hand wheel once assembled.
That all for today, they had us running last night so running on empty.
Thanks for stopping by.
Paco
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.Todays high was 76ºF, just beautiful.
