V70 rear wiper issues + solution

[Brendan W]

Originally Posted by ShadeTek

I wonder if it is possible to 3D print a camgear?

I've just been offered a trial on one if I can provide dimensions. Anyone out there with one in the spares bin?

[foggyjames]

Yes, I have a partly-stripped one in the spares bin which I can donate if it allows reproduction ones to be made.

I have previously enquired about the availability of spares, to no avail.

cheers

James

[Brendan W]

Originally Posted by foggyjames

Yes, I have a partly-stripped one in the spares bin which I can donate if it allows reproduction ones to be made.

I have previously enquired about the availability of spares, to no avail.

cheers

James

Can you PM me a picture?

[I-S]

3d printing might work, but from a functional standpoint. Gears are surprisingly complicated in terms of tooth profiles and engagements, plus 3d printing (except at aerospace levels) doesn't give a finish smooth enough or a gear round enough - we use 3d printed prototype gears at work, yet the moulded item is invariably better - smoother running and stronger. I think that a 3d printed one would run poorly and fail quickly.

It is distinctly possible that these gears are bought in from a supplier's standard range.

[Brendan W]

Originally Posted by I-S

3d printing might work, but from a functional standpoint. Gears are surprisingly complicated in terms of tooth profiles and engagements, plus 3d printing (except at aerospace levels) doesn't give a finish smooth enough or a gear round enough - we use 3d printed prototype gears at work, yet the moulded item is invariably better - smoother running and stronger. I think that a 3d printed one would run poorly and fail quickly.

It is distinctly possible that these gears are bought in from a supplier's standard range.

True and true.
No.1 son finished building a machine last week and is keen to put it through it's paces. The way this technology is growing I am expecting to have to rewrite my original assessments of it any day now.

[Crazy Badger]

Thanks for the guide, which gave me the courage to take mine apart!

My symptom was a stuck arm, generally on the way back from a sweep.

Getting the arm off proved to be one of the most difficult jobs, and the most expensive as I snapped it! Even with just the remains, it was a bugger to remove and I can't see how I'd have got it off without it breaking. Removing the unit was pretty straight forward, as was getting inside.

Removing the shaft was a nightmare too, and I think this was the problem as even once everything was free it was very difficult to turn the axel. Once it was out though, and after a clean and re-grease everything went together well, although I might have an o-ring in the wrong place.

Fitted back on the car without any issues and it looks to be working fine. New wiper arm ordered so will see when that's fitted back on.

[ShadeTek]

From what I remember of stripping down my rear wiper motor assembly, there were copper electrical contact parts on the main white sprocket which were held in place by spigots that had been melted down to hold the copper contacts in place. If you are printing one of these off you will have to factor this in if my I am remembering it correctly.

I will be stripping mine down again in the near future as when I use my rear wiper first thing in the morning , it is pausing mid-stroke. It did this once before and I had to strip it down and bend the auto-park contacts back into place. I also bought one fo these to make life easier.

http://www.ebay.co.uk/itm/PROFESSION...item1e7b1e91f3

[Crazy Badger]

Originally Posted by Crazy Badger

New wiper arm ordered so will see when that's fitted back on.

New wiper arm is back on and it's working like a dream, and almost flies from side to side. The replacement arm not quite up to OE standards and it's parked at a slight downwards angle, but it does have a better wiper blade mount and was less than £20 including the blade.

Thanks again!

[R-P]

You're welcome...

I'm still none the wiser about how the resting position works. My contacts are in place, but when fitting the arm at the bottom of the glass, it first goes down 7.5cm/3" before doing a proper sweep.
So it always wipes part of my rear-door, or I have to assembe it facing slightly upward, hence it being annoyingly in my field of rear-view vision.
I tried changing the white wheel a tooth or two to either side from the rest of the assembly, but it took me a while to understand this does NOTHING to change the positions of the sweep. The motor always runs the wrong direction for a moment before switching directions. (Edit: just rereading my own first post, the motor does NOT change direction, it runs one direction only, but I still don't get it).

[foggyjames]

The resting position is determined by the layout of copper tracks on the big white cog. It's possible they've slipped...?

Brendan - what exactly did you want a picture of...the cog? The extent of the damage to it?

cheers

James