Last modified: 2026-09-18 09:48:31
< 2026-09-16 2026-09-18 >Some more machining on these:
The D-shaped pocket in the top is in aid of aligning the steering arm, if I put a D-shape on the steering arm at the correct angle then when it drops into this piece to get welded it will be at the correct angle automatically.
The 16mm hole in the middle is interpolated, and seems to be coming out a bit under-size, this is potentially good as long as the bolt still goes through it because it means it is aligned more accurately. And if the bolt won't go through it I can just enlarge it until it does.
And finished:
Needs a bit of deburring etc.
The M16 bolt does not fit through the holes, they measure about 15.7mm. Unsure whether I'm going to rectify this by picking up the hole and interpolating it again, or just use a 16mm drill. I don't have a 16mm drill that is suitable for steel but I do have a 16mm masonry bit but I recall it doesn't work very well in steel. But may be adequate just to enlarge this by .3mm of diameter?
Update: cock, just realised one of these is wrong because I forgot to account for the 3mm tool radius when setting coordinates. What do I do about this?
3mm error across 80mm span is 2.15 degrees, which is too much to tolerate. So I need to either remember this error when fitting the spindle, and make sure the spindle angle is set relative to the actual kingpin axis instead of the plane that I was planning to use as a reference surface, or else make the part again.
Making it again is easy enough but means buying material again, paying delivery costs etc. again, and waiting for it to arrive.
I kind of feel like making it again is the right thing to do.
Annoyingly if I'd just not re-set coordinates each time I loaded material it would have been closer than this because I was eyeballing it at about the same distance relative to the edge of the vice jaw
I do need to make another steel order anyway, because I need to get the 36mm round tube for the beam axle. So I guess just add the tiny bit of box section to that order and remake it later. In the mean time I could make up one complete upright, but would it be more efficient to do them both at the same time? Probably. Since I already basically know how big I need the beam axle to be I may as well order it now. I can still work on the other upright parts for now, just can't weld them up until I have both sets complete.
Steel to buy is:
Also, I fitted the 60mm spring shackles just to see how they would work, and I stood on the front of the chassis, and they folded over completely and locked against the chassis, and that's with only about 1 kN of load, so definitely not sufficient if I want the front suspension to be able to take 3 kN without locking up. So I definitely need to make the 80mm shackles.
< 2026-09-16 2026-09-18 >