How To DIY SDHQ Knuckle Gusset Writup

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t_j

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So I did the installation of the SDHQ knuckle gusset kit over the last week or so and am very pleased with how they turned out.

Tools/parts required:

* Tig welder and safety gear
* Plenty of 70s2 filler and a full tank of argon
* A good stock of pre-ground tungsten
* Grinder with a flapper wheel (preferable edge usable)
* Oven
* Sand pit (2.5'x2.5'x12") (One 10'x12"x2" length of wood, and 5x 60Lbs bags of sand, one plastic drop cloth to use as a liner)
* Blow gun or can of air cleaner

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* Left and right knuckles (AL3Z3K185B and AL3Z3K185B ~$85 each)
* SDHQ Gusset kit - $125

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* Some form of paint/finish - I had mine powder coated.


This will take you a whole day from start to finish and requires a decent amount of physical effort moving the parts around.

1) Turn on the oven to the warm setting or ~100F if your oven goes that low.

2) Clean up the surface of the knuckle where the gusset is to be welded.

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3) Grind the gusset to get a good fit against the knuckle.

4) Clean up the surfaces of the gussets where the welds are going to be done.

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5) Place the knuckles in the oven for at least one hour. If you can't remove them with your bare hands they are too hot and should be allowed to cool briefly to a touchable temperature.

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6) Remove the knuckles from the oven and place one in the sand pit berried and the other on your welding table.

7) Tack in the gusset on the first knuckle and then pick an end of the knuckle and run the first 1" of bead.

8) Move the first knuckle to the sand pit and bury it and move the second knuckle to your work table and blow it clean the dust off with a blow gun.

9) Repeat step 7 on the second knuckle.

10) Swap the knuckles making sure to bury the one being returned to the pit and cleaning off the one removed with the blow gun.

11) Now on the first knuckle run 1" of bead at the opposite end to the last one.

12) Swap knuckles, repeat step 11.

13) Continue to loop steps 11/12 until you have completed the bead on one side of the gusset.

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14) Return both knuckles to the pit and allow to cool for 30 mins. If you allow them to cool back to room temperature you must repeat step 5 before continuing.

15) Repeat steps 11/12 to run the bead on the other side of the gusset.

16) Repeat step 14.

17) Tack in the second piece of the gusset kit and run your first inch of bead.

18) Swap the knuckles and repeat step 17 on the second knuckle.

19) Continue to weld 1" beads at opposite ends of the knuckles in turn in the same fashion as you did for the first set of beads.

20) Completely bury both knuckles in sand and allow to cool to room temperature.

21) Apply finish of your choice making sure to mask of all the ground surfaces of the knuckle before hand.
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---------- Post added at 08:49 PM ---------- Previous post was at 08:39 PM ----------

@hole shot - Here is how they turned ou!
 
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t_j

t_j

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Great write-up! Keeping the spindles warm is definitely an important part of the puzzle to ensure it is done correctly!

Yeah, they stay warm for almost the whole process as the heat dissipates from the area last worked on. I think more important is making sure they cool very slowly, if they cool too fast then the the parts will crack, luckily the knuckles are very strong so you are more likely to get a crack in a bead than in the knuckle itself.
 
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