D Special headlight assembly

[GreenBlood]

You're certainly not having much luck Don. I tried my printed bits at the weekend, the 3 cut nylon clips. They were stiffer than original, as you'd expect being new and unworn, but not unduly so.
Depending on the quality of the printer, male features tend to be slightly (technical term) oversize and female features slightly (technical term) undersize. In other words a pin is bigger, a hole is smaller.
Our desktop printer errs by 0.2mm in this regard so you can end up with 0.4mm clash radially or 0.8mm clash across the diameter if this makes sense.
The NZ printed trial parts I have here are 0.05 oversize/undersize which is acceptable and is why they work.

SF

All above is normal in therms of manufacturing considerations and once understood can be allowed for.

That fits with the part you sent up to me, it was a very tight fit into the headlight bracket and refused to accept the adjusting screw. You had explained that it wasn't the correct material, just a proof print so I didn't persist.

For Don, if he needed to use the printed parts he received a drill bit into the hole to open it up may have helped. Seems he is out of trouble though with used parts. The soft part could be be easily cut by hand using a rubber block, it essentially only holds the clip up against the bracket.

The important thing is we now have these parts modeled, with minor corrections they will exist for posterity. Thanks Printerman

Cheers
Chris

 

[Don B. Cilly]

The important thing is we now have these parts modeled, with minor corrections they will exist for posterity. Thanks Printerman

I'm afraid the minor corrections will have to be made if they are to be good for posterity.

On the round bits, first I would do away with the cut corner, second would try to correct the center hole.
(Or maybe the tight fit tightens the hole?)
That is difficult. too big, the light pops out, too small, won't go in.
We have very fine tolerances here. Tough. Especially if you have to go to New Zealand to print them or your local printers are useless.
Mine, the material looks good. Looks and feels nylon. But it is hard to tell.

The soft bit.
Material seems to be difficult.
I think we could try actual DIY silicone, so what we'd need is a mold.

Fill it will sillycone, scrape the top, allow to set.
Nylon would be probably good in the way that silicone wouldn't stick to it too aggressively.
The part with the round fit would have to go at the bottom of the mold.

I think we could give it a try mainly because, whereas the tolerances on the round bits seem to be critical, on the soft bit they can't be.

 

[ScotFrog]

I'm afraid the minor corrections will have to be made if they are to be good for posterity.

On the round bits, first I would do away with the cut corner, second would try to correct the center hole.
(Or maybe the tight fit tightens the hole?)
That is difficult. too big, the light pops out, too small, won't go in.
We have very fine tolerances here. Tough. Especially if you have to go to New Zealand to print them or your local printers are useless.
Mine, the material looks good. Looks and feels nylon. But it is hard to tell.

The soft bit.
Material seems to be difficult.
I think we could try actual DIY silicone, so what we'd need is a mold.

Fill it will sillycone, scrape the top, allow to set.
Nylon would be probably good in the way that silicone wouldn't stick to it too aggressively.
The part with the round fit would have to go at the bottom of the mold.

I think we could give it a try mainly because, whereas the tolerances on the round bits seem to be critical, on the soft bit they can't be.

Don't give in yet Don,
I've modelled the soft bit as a simple 2 part mould set. Your idea of printing in nylon and forming a silicone part is good. I'll send the 2 parts to you as STL files. They won't be expensive (not in dollars but perhaps in exasperation) and will allow you to mould quite a few samples. I've modelled them size for size, i.e. no allowance for printing errors and no allowance for moulding shrinkage etc. As you say being a soft part it will probably be very forgiving.
The 2 halves will nest via 2 locating features you can see on the mating surfaces. I think fill the cavity half (shown in green) with silicone and offer up the core half, squeezing the excess silicone out, maybe even pinch shut in a vice. It'll be messy but the silicone shouldn't stick to the nylon as you suggest and therefore easy to clean up.
Some siicones set in the presence of water so wet the halves with soapy water before filling with silicone.
If you need anything else just ask.

SF

 

[Don B. Cilly]

Oh boy
Means I'll have to talk to the donkey muppet again.
But then, I'm curious. Not so much about how many months he'll take to print it, or how many modifications he'll want, but as to how it will work.

It should (work out).
And it's got lots of variables, such as which silicone/other-material is best, how long to let it set before you close it - silicone needs air for the acetic acid (solvent) to evaporate.. and so on. Endless entertainment for those how-to-spend the-next-half-hour moments...
and once I have it, I don't have to depend on the muppets, so, hey

 

[ScotFrog]

Oh boy
Means I'll have to talk to the donkey muppet again.
But then, I'm curious. Not so much about how many months he'll take to print it, or how many modifications he'll want, but as to how it will work.

It should (work out).
And it's got lots of variables, such as which silicone/other-material is best, how long to let it set before you close it - silicone needs air for the acetic acid (solvent) to evaporate.. and so on. Endless entertainment for those how-to-spend the-next-half-hour moments...
and once I have it, I don't have to depend on the muppets, so, hey

And I was quite fond of the Muppets too, Kermit and Miss Piggy! Although I heard they've had a bit of a bust up recently. What is the world coming to?

SF