m42 x 1.0 extension tube set

Interested in used equipment to buy, sell, or trade? Post here to find other members with matching needs. Personal equipment only, no dealers please.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

dolmadis
Posts: 809
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

m42 x 1.0 extension tube set

Post by dolmadis »

Hi

Does anyone have a source please for a m42 x 1.0 extension tube set?

Or a set to sell perhaps?

Thanks

John

Online
Scarodactyl
Posts: 618
Joined: Sat Apr 14, 2018 10:26 am

Re: m42 x 1.0 extension tube set

Post by Scarodactyl »

Are the cheap Chinese ones not good/precise enough for your application? Hard to beat the pricing anyway, though the wait is a bummer.

rjlittlefield
Site Admin
Posts: 21406
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
Contact:

Re: m42 x 1.0 extension tube set

Post by rjlittlefield »

Try Amazon. Here in the US, searching Amazon for m42 extension tube shows several listings in stock with projected delivery in a few days.

Avoid anything that says T2 and/or "astro"; those will be 0.75 pitch. But anything that says just M42 and film/digital/lens will be 1.0 pitch.

--Rik

dolmadis
Posts: 809
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: m42 x 1.0 extension tube set

Post by dolmadis »

Cheap Chinese are 0.75 pitch as far as I can see and not 1.0. Being in the UK I need to look at Amazon UK once again Rik.

best, John

dolmadis
Posts: 809
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: m42 x 1.0 extension tube set

Post by dolmadis »

The first set from my box of old extension tubes from the box did not like the known M42x 1.0 thread I was joining to. So I assumed that they would all be the same.

WRONG..........

The next set I tried were OK.

Thanks All...........Normality restored.

Best, John

ray_parkhurst
Posts: 2839
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Re: m42 x 1.0 extension tube set

Post by ray_parkhurst »

I'm not surprised about the compatibility issue. I have seen quite a few issues with "M42x1" male threads not interfacing well with similar female threads. This is a big problem with some of the Pentax Auto Bellows I've handled. There are two types...first has radial set screws that hold the M42 front mount in place...and second has 4 coaxial screws that hold it in place. The radial ones distort very slightly when the set screws are tightened, and this will cause some M42 extensions and accessories to bind. The bellows with the 4 coaxial screws seem universally less prone to this problem. This is only an example, but may be indicative that the typical extensions available on eBay (and Amazon) are machined to a bit too tight a tolerance. I have spent a fair amount of time "breaking in" some extensions and adapters so beware that compatibility is not just a 1mm vs 0.75mm pitch issue.


Post Reply Previous topicNext topic