|andrew lyner||16/12/2019 16:41:31|
|151 forum posts|
I hope this is a suitable place to post this question.
I have a Kitchenaid Artisan food mixer and it is almost perfect. It does have one stupid problem and that is the hinge pin that the top pivots round when it's lifted. Anyone who has had anything to do with this mixer will know what I mean about the construction of the mixer.
The pin is about 9mm and s/s. It goes through a meaty 'foot' which is part of the top casting and a pair of holes each side in the casting of the base. It is held in place by a grub screw, half way along and the screw shakes loose after a few months' use in bread making, things start to rattle and the pin starts to come out. Breadmaking is quite a heavy duty operation compared with cakes. (I don't dare starting on a weekly cake bake - get thee behind me Satan!!!`) but the motor seems to cope well enough with a 600g (flour) mix.
The problem is all over Google and only solution I can come by is to screw the grub screw in again - as tight as you can.
If only I could find a link where someone has fixed the problem 'properly', then I would do what they've done. I can't imagine a seasoned ME member who has heard 'that' noise and not wanted to do something about it.
Do I really have to put bushes in the castings, to sort it all out? What's the general opinion / experience?
17088 forum posts
Thread lock on the screw?
|andrew lyner||16/12/2019 16:47:41|
|151 forum posts|
That's an idea but I get so cross at spending loads on one squirt from a tube which is out of date by the time I need another squirt. It would certainly be a quick solution.
Thanks for the reply, btw
|Brian Wood||16/12/2019 16:50:22|
|2072 forum posts|
Put a flat on the pin for the grub screw to bite into, then thread lock as JasonB suggests
Alternatives are to fit end screws and a thick washer behind each to contain the pin and prevent it 'walking' out
|Dave Halford||16/12/2019 16:56:16|
|564 forum posts|
Doesn't really go out of date, old stuff still works the same.
|Brian G||16/12/2019 16:56:45|
|651 forum posts|
Is there room to fit a longer pin with a head one end and a groove for an E clip at the other (or even a washer and split pin)? Crude but pretty much vibration proof.
|355 forum posts|
If there is room put another grub screw in after the original.
Edited By Oldiron on 16/12/2019 16:59:46
|Jeff Dayman||16/12/2019 17:24:19|
|1723 forum posts|
If you don't like the price of Loctite you could try tiny tube of super glue (CA glue) from the pound shop / dollar store. Epoxy from same source might also hold the pin in.
Does the setscrew sit on the round OD of the pin? It might hold better if you grind a flat on the pin with a disk in a dremel type tool to receive the end of the screw.
|Nick Clarke 3||16/12/2019 17:47:47|
519 forum posts
|Cornish Jack||16/12/2019 17:48:51|
|990 forum posts|
Loctite certainly does go on and on - mine bought part used over 20 years ago, still working. Keep Super glue in the refrigerator.
|Neil Wyatt||16/12/2019 20:27:13|
17097 forum posts
twist of teflon tape or even nylon thread around the grubscrew before tightening it.
17088 forum posts
Dab of paint or even nail varnish if you wear it will do as a weak thread lock and be easier than superglue should you need to get the screw out at any time.
|Howard Lewis||16/12/2019 20:49:54|
|2748 forum posts|
How about making a poor mans version of the grubscrew with a Nylon insert?.
Hold a short piece of fishing line in the tapping, as you screw in the grub screw. Hopefully, this will, generate enough friction to prevent the grubscew backing out.
|andrew lyner||16/12/2019 23:06:57|
|151 forum posts|
This is a great little Engineering Problem and it needs experience to solve it. The right choice of materials in the first place would have avoided this being such a frequently reported fault in all the Kitchenaid models .It's not a difficult thing to get right - it's hardly like an engine camshaft, operating at 20,000 revs!. In the whole lifetime of the unit, used a few times every day, the hinge would hardly have to operate more than 20,00 times in a ten year lifetime.
"enough friction to prevent the grubscew backing out." The pin seems to be very hard and the grub screw doesn't manage to mark it al all -so there is virtually no movement and the grub screw can't (by the nature of the geometry) work up any compression or stretch, which is what most properly tightened bolts work on.
When the screw goes slack, there is some slop in the inner hole (the one on the top half of the machine) so merely replacing the pin with one with 'ends' on it, to stop it moving out. That slop means the top of the machine rattles about and I need to stop that - just for quietness.
I like the idea of grinding a small flat on the pin and then using thread lock. I was even wondering about putting a bit of a slot / hole and grinding a point on the set screw for it to bite into. Probably a slightly softer pin would do the job and allow the grub screw to hold it better. It's a very quick job to make changes so I can experiment. I may buy some silver steel and even harden it (?) or would it be too brittle in that application?
|not done it yet||16/12/2019 23:18:32|
|3946 forum posts|
An ‘O’ ring behind a washer or end cap is often sufficient to prevent movement and provide some friction. Otherwise fit shims to reduce any lateral movement?
|andrew lyner||16/12/2019 23:27:31|
|151 forum posts|
I see where you're going but the slop is radial and I don't think shims are needed. The pin needs to be pushed radially; It's strange but any wear should be pin against the outside four holes but they are tight enough. the central hole seems to be where the slop movement is.
|Michael Gilligan||16/12/2019 23:40:34|
14783 forum posts
Grubscrews with nylon inserts or patches are readily available.
|Mike Poole||16/12/2019 23:45:47|
2331 forum posts
a Couple of R clips seems to be one mod being sold, it should be possible to drill the existing pin to fit the clips
|Ron Laden||17/12/2019 05:19:07|
1624 forum posts
Just dimple or flat the pin at the screw contact point and threadlock the grub, simple, easy and cheap you can get a small bottle of threadlock for £3-£4 hardly breaks the bank and sorts the problem.
Or have you got a headed screw of the same thread with a nut to fit, tighten the screw against the flat and lock in place with the nut, even cheaper than buying threadlock.
Edited By Ron Laden on 17/12/2019 05:29:00
|Clive Hartland||17/12/2019 07:14:44|
2503 forum posts
Nail varnish, degrease parts first.
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