Thread size of Raymarine ST60 MHU vane screw?

[nigelmercier]

I'm trying to find the thread size of the tiny screw that holds the vanes onto an ST60. Being American, I suspect it may be imperial.

Measured details are:

OD: 1.9mm / 0.0748" or about 75 thou
Turns: 2.5 turns per mm / 63.5 tpi

Anyone got thread tables that go this small?

 

[earlybird]

How accurate are your measurements. No. 1 UNC is 0.075 inch dia. X 64 tpi.

 

[nigelmercier]

How accurate are your measurements. No. 1 UNC is 0.075 inch dia. X 64 tpi.

That's about as close as I'm going to get, thank you.

Next problem, where can I get one? All my searches come up with 1/4 or 1/8 etc.

 

[Graham_Wright]

I'm trying to find the thread size of the tiny screw that holds the vanes onto an ST60. Being American, I suspect it may be imperial.

Measured details are:

OD: 1.9mm / 0.0748" or about 75 thou
Turns: 2.5 turns per mm / 63.5 tpi

Anyone got thread tables that go this small?

M2 is Ø2 (screws tend to have a smaller diameter than nominal) and pitch is 0.4 mm.

At the SBS, one of their designers told me that the company is now owned by an American outfit (not Raytheon I don't think) and manufacture is in Mexico.

Mine kit was made in Hungary (again, I think!) but design is still in the UK. I would expect metric to rule.

If stuck try sales@allcap.co.uk in Gloucester. They supply all my fixings and fasteners (and if 1 off M2 doesn't interest them, ask me).

 

[nigelmercier]

M2 is Ø2 (screws tend to have a smaller diameter than nominal) and pitch is 0.4 mm.

Thanks Graham.

 

[Andrew G]

Nigel,
G'day. I hope I havn't missed the answer again, and I know you are just looking for the screw, but two come as part of the ST60 Windvane Repair Kit, Part No. E28081 Au$55 (I've had to get the kit because the local Cockatoos have destroyed my vane, rotors and VHF antenna). Cheers, Andrew

 

[nigelmercier]

Yes, I bought a "new" repair kit on eBay, but it came with no screws.

I've also bought a couple of complete MHUs, so I can keep a spare. I'm currently stripping them down and taking pictures. They are the newer model with the egg-shaped body; you need to use a screw as a puller to extract the bearing assembly. I didn't want to potentially damage the screw without having some spares. I've ordered some M2 screws in A4 stainless, they have Allen heads, so a better option than Pozidriv.

 

[nigelmercier]

I've ordered some M2 screws in A4 stainless, they have Allen heads, so a better option than Pozidriv.

I can confirm that the screws connecting the vanes to the MHU are M2. Thanks all.

Note to self: must remember that metric screws are quoted by pitch, 2.5 turns per mm is pitch 0.4 mm.