When your new crystal won't go in properly straight....

[55grainvmax]

Blumo, mods delivered - Crystal Times purple AR DD, Crystal Times Polished Chapter Ring and LCBI insert.

Stock crystal pops off a treat, catch the gasket and pop out the OE chapter ring. 

Bezel off, oe insert out and double-sided sticky ring trimmed out, fitted to insert and thence to the bezel and then the bezel pressed back on. Bingo.

I cannot however get the crystal as level as it should be and there's a slight "high" between 3 and 6. 

I'm happy with the overall effect but time has run out so this week I'll drop the crystal and start again with all patience intact and no time pressures.

The crystal gasket: how should it sit relative to the chapter ring - should it sit loosely abvove it awaiting the arrival of the crystal or does it sit slightly behind the chapter ring? I have a slight nip at one point and i wonder if this is the cause (or result) of the new crystal not being exactly level?

And what size of concave bush should I use to press down the crystal - the biggest diameter within the circumference of the crystal, or a smaller one?

[55grainvmax]

Here's how he looks....complete with my bad crystal alignment.😭😭😭

[stuart]

I would say the crystal gasket got misaligned when fitting the crystal. I now use a Seiko S-220 press set for nearly all my crystals. The fitment of the dies and the press design pretty much always give straight insert of the crystal. My screw down Horotec press, although very strong, doesnt have anywhere near the same control of alignment as the Seiko one.

[rob3rto]

All it takes is 0.5mm of difference in crystal diameter or thickness at the mounting edge and it will mess it all up.

[55grainvmax]

Aug 19, 2018 8:23:48 GMT -8 stuart said:

I would say the crystal gasket got misaligned when fitting the crystal. I now use a Seiko S-220 press set for nearly all my crystals. The fitment of the dies and the press design pretty much always give straight insert of the crystal. My screw down Horotec press, although very strong, doesnt have anywhere near the same control of alignment as the Seiko one.

Yes, interesting what you say about press quality. My main hobby involves reloading rifle ammunition and, in that field, there are "strong" presses and "small tolerance" presses. 

Back to my question though, do you use the largest possible press bush or does it not matter? 

I'll maybe see this week if I can tease the gasket out and try again; if I can't I can see my excellent friend in Germany receiving a job from me.

[stuart]

I'm just a hobbyist so dont take my experiences as definitive

For mineral / sapphire I use a die which is close to the maximum for the crystal or fits its profile best. Mine are metal dies, so I first use the die / press to seat the crystal into the watch to ensure its going in straight, then fit a piece of clear plastic between the die and the crystal and push down harder, hoping to avoid the metal die causing any scratches.

For the curved acrylic crystal I would use a die slightly larger than the crystal, my thinking is the die will push down around the outside edge causing the crystal to compress slightly in size so that it fits easier into the case.

I have one project case where I just cant get the crystal to fit correctly, I think the gasket is the wrong size for the crystal / case and I cant get the crystal to fit. New gaskets are on order, but since its a project I tell myself thats all part of the fun haha.

[acidstain]

As wide as possible for the crystal side. Specially if it’s domed.

If after 1-2 tries your crystal still won’t sit flush, 99% of thr time the gasket has been pinched on 1 side and will need to be replaced.

Regarding where the gasket should sit, not it should never sit loosely above anything. Where the gasket sits is where it dits perfectly (with a tiny bit of tightness in it).

I use a lever type press. Yes i have accidentally pinched gaskets a handful of times before, but considering that i have pressed crystals for over 10 years at a rate of 10+ a day, pinching like 3-4 times ain’t that ba d.

[55grainvmax]

Thanks for your inputs acidstain and, yes I have pinched the gasket so I've ordered replacements which will be shipped off with the watch to my good friend George in Germany: I shall let an expert take over.

[Adrian-VTA]

I've started turning down jobs that include the CT domed crystals.

They are extremely difficult to fit and almost never fit correctly without 45 minutes of messing around. I think they need a revision on the underside bevel to work correctly. I reckon 75% of the parts in the field are fitted lopsided.

The stock crystal fits like a dream and I don't have these sorts of issues.

[55grainvmax]

Aug 28, 2018 19:39:06 GMT -8 Adrian-VTA said:

I've started turning down jobs that include the CT domed crystals.

They are extremely difficult to fit and almost never fit correctly without 45 minutes of messing around. I think they need a revision on the underside bevel to work correctly. I reckon 75% of the parts in the field are fitted lopsided.

The stock crystal fits like a dream and I don't have these sorts of issues.

Adrian, thanks for your input which is helpful in preventing a rookie like me from feeling inadequate.