Very stiff Chinese M42 adapters

Jean Poitiers · 03-27-2012, 10:32 AM

Bonjour,

Not worth the hassle IMHO ... it's $24.95 at B&H. More expensive, oui, but worth it in the long haul.

I had mine sent to a family member in the States who then re-mailed it (international) to me in France.

Didn't bother to find out if B&H would mail this to France ...

http://www.bhphotovideo.com/c/product/673977-REG/Pentax_30120_Mount_Adapter_K.html

Salut, J Frog

ultraviolet · 03-27-2012, 11:15 AM

Originally posted by kcobain1992

Very stiff Chinese M42 adapters

Sorry, if some one already suggested this or tried.
I had similar problem ( I have 10 of these knockoff, works just fine). What I noticed in my case, that there should be a gap between the lens base and the adapter. Some older takumars don't have those very slim steps around the neck, but some 3rd party M42 has it ( I will post some pics latter).
So, what I did is, put a very thin ( thick enough to allow the rotation but thin enough to seat firmly) paper ring (same or smaller diameter of the adapter) in between the adapter and lens. Hope that helps.

vladimiroltean · 03-27-2012, 04:00 PM

With lenses with narrow base (Industar 50-2, Helios 44-2), the adapters can actually move in the mount, but with excessive friction as well, and sometimes they do not come off with the lens, even if there is no retaining clip. Clearly there is some mis-machined part, which I will have to file.

vladimiroltean · 03-31-2012, 03:43 AM

I have partially solved the problem:
With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale.

sterretje · 03-31-2012, 03:48 AM

Originally posted by kcobain1992

... but they are 45 degrees off with the distance scale.

It's annoying but even original Takumars with original Pentax adapters can be off; not by 45 degrees but they are off.

vladimiroltean · 03-31-2012, 10:26 AM

Well, none of my M42 lenses were out of whack with the original adapter, including 2 Takumars. I can adjust the Jupiter easily, but I don't know for the others.

excanonfd · 03-31-2012, 12:00 PM

Originally posted by kcobain1992

About a month ago I ordered three flangeless adapters (knockoffs of the original) for $7.50 each from ebay, hoping that I can remove the metal clip and use them to semi-permanently adapt some M42 lenses to K. They arrived today, and unfortunately they are VERY stiff. I mounted them on the lenses, but these do not rotate in the camera's mount more than, say, 5 degrees. As a simple glance, I didn't see any obvious difference between the original Pentax and these, so maybe you can help me solve my problem.

I've had the same problem from some of the knockoffs from China, for some strange reason they would not work with any Pentax m42 lenses but work very well and snug with the Soviet and East German lenses. The spacing between the lugs and the flange was slightly less than the original Pentax m42 adapter. If you have a digital caliper, measure the spacing between the flange and the lugs on both adapters. If you don't have a caliper, you can still do it but becomes a bit more tedious (many trial fittings).

Using an emery board. gently sand the lugs constantly checking the measurements or you can sand each of the lugs a fixed number of strokes, clean the adapter (soapy water bath, rinse and dry) mount the adapter to a lens then try mounting the lens on a K body camera. Repeat the process until you are satisfied with the fit. The adapters are made of brass and won't need too much sanding to get them to fit properly. I find the original m42 adapter too loose to be used as adapters for a semi-permanent conversion from m42 to K lens. The knockoffs are much better suited for semi permanent M42 to K conversion, if you make some modifications.

I have to get a few more myself, when these knockoff adapters are screwed on tight to the m42 lens, where is the red dot in relation to the lens' focus hash mark? Trying to find a seller that has adapters that place the mounting dot close to the focus hash mark is more important than the fit imo. Please provide the name of the seller if the red dot is near the lens focus hash mark.

**Lowell Goudge** · 03-31-2012, 12:45 PM

Originally posted by kcobain1992

I have partially solved the problem:
With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale.

All this means is that you mount the adaptor with the industry lens and then just unscrew that lens and use what you want. I still suggest you look at the spacing between the two flanges though because it seems off

vladimiroltean · 03-31-2012, 01:08 PM

Hi and sorry, not being a native English speaker, some of the terms you used simply overwhelmed me

I would like to be of any help, but I need to know what you are referring to by "the lugs", "flange" and "focus hash mark".
Here are 2 scans of the adapters, please indicate on them the parts that you mentioned earlier.

excanonfd · 03-31-2012, 01:26 PM

Originally posted by kcobain1992

Hi and sorry, not being a native English speaker, some of the terms you used simply overwhelmed me

I would like to be of any help, but I need to know what you are referring to by "the lugs", "flange" and "focus hash mark".
Here are 2 scans of the adapters, please indicate on them the parts that you mentioned earlier.

Hi,

The lugs would the three locking tabs on the adapter that would go inside the K body bayonet mount (2nd picture), the flange is what mates to the m42 lens (1st picture). The focus hash mark is the the focus indicating line on the lens with the DOF markings. If the red dot is within +/- 15 degrees of the hash mark, it would be ideal. Lining up dead on with the hash mark isn't all that good either because of the flash housing beak on the Pentax DSLRs obscures the mark but it's better than having the mark upside down (I've had adapters do that too).

newarts · 03-31-2012, 02:38 PM

Originally posted by kcobain1992

I have partially solved the problem:
With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale.

Does it help to increase shim thickness? It seems to me you should be able to increase shim thickness until the lens stops wherever you'd like. Once you get things adjusted properly, use the little screw you took out of the adapter to clamp the adapter onto the lens.

Use a file or fingernail emery board to smooth the adapter edges & remove material where the lugs (ears) touch the mounting flange.

vladimiroltean · 03-31-2012, 04:11 PM

I understand now. Each piece of paper that I add offsets the focus mark by 45 degrees. That would make 8 shims, all at once. I suppose that would affect infinity focus. Actually, I'm just too lazy to cut 8 pieces just to test that. I have thought of it too. There must be a smarter solution though.

**k0og** · 03-31-2012, 04:45 PM

Kcobain1992,

It appears you may have solved your problem, but I'll mention a problem I had with one of my cheap M42 adapters. It would mount on the camera (without a lens), but was a little too tight. As some others have mentioned, it looks like the thickness of the inner flanges in your cheap adapter is more than the original adapter. I filed down the inside surface of the three flanges as shown from your picture:

Of course, after filing I thoroughly cleaned all the metal particles from it before trying to mount it in my camera.

Now it works as smoothly as an original Pentax adapter.

-Joe-

MacRider71 · 04-01-2012, 03:25 AM

Which ebay seller did you get those from? I'm looking at buying some and wish to steer away from THAT one! lol

**Lowell Goudge** · 04-01-2012, 05:28 AM

Originally posted by k0og

Kcobain1992,

It appears you may have solved your problem, but I'll mention a problem I had with one of my cheap M42 adapters. It would mount on the camera (without a lens), but was a little too tight. As some others have mentioned, it looks like the thickness of the inner flanges in your cheap adapter is more than the original adapter. I filed down the inside surface of the three flanges as shown from your picture:

Of course, after filing I thoroughly cleaned all the metal particles from it before trying to mount it in my camera.

Now it works as smoothly as an original Pentax adapter.

-Joe-

Not sure if it is the thickness, or the fact that the thickness has resulted in reducing the space between flanges, but filing that down probably would make things go in easier, however, the OP has also noted that some lenses work better than others suggesting that there is also an issue with the top flange relative to the camera mount. Therefore I think it is also an issue of being able to install the adaptor with some lenses, but once installed, he should be ok

03-27-2012, 10:32 AM	#16
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076	Send 'em back ... *Bonjour,* Not worth the hassle IMHO ... it's $24.95 at B&H. More expensive, *oui, but worth it in the long haul. I had mine sent to a family member in the States who then re-mailed it (international) to me in France. Didn't bother to find out if B&H would mail this to France ... http://www.bhphotovideo.com/c/product/673977-REG/Pentax_30120_Mount_Adapter_K.html Salut, J Frog*

03-31-2012, 02:38 PM	#26
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by kcobain1992 I have partially solved the problem: With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale. Does it help to increase shim thickness? It seems to me you should be able to increase shim thickness until the lens stops wherever you'd like. Once you get things adjusted properly, use the little screw you took out of the adapter to clamp the adapter onto the lens. Use a file or fingernail emery board to smooth the adapter edges & remove material where the lugs (ears) touch the mounting flange. Last edited by newarts; 03-31-2012 at 03:00 PM.

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03-27-2012, 11:15 AM	#17
ultraviolet Pentaxian Join Date: May 2010 Photos: Albums Posts: 687	Originally posted by kcobain1992 Very stiff Chinese M42 adapters Sorry, if some one already suggested this or tried. I had similar problem ( I have 10 of these knockoff, works just fine). What I noticed in my case, that there should be a gap between the lens base and the adapter. Some older takumars don't have those very slim steps around the neck, but some 3rd party M42 has it ( I will post some pics latter). So, what I did is, put a very thin ( thick enough to allow the rotation but thin enough to seat firmly) paper ring (same or smaller diameter of the adapter) in between the adapter and lens. Hope that helps.

03-27-2012, 04:00 PM	#18
vladimiroltean Veteran Member Join Date: Dec 2010 Location: Bucharest, Romania Photos: Gallery Posts: 1,465 Original Poster	With lenses with narrow base (Industar 50-2, Helios 44-2), the adapters can actually move in the mount, but with excessive friction as well, and sometimes they do not come off with the lens, even if there is no retaining clip. Clearly there is some mis-machined part, which I will have to file.

03-31-2012, 03:43 AM	#19
vladimiroltean Veteran Member Join Date: Dec 2010 Location: Bucharest, Romania Photos: Gallery Posts: 1,465 Original Poster	I have partially solved the problem: With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale.

03-31-2012, 03:48 AM	#20
sterretje Veteran Member Join Date: Dec 2008 Location: Roodepoort, South Africa Photos: Gallery \| Albums Posts: 3,561	Originally posted by kcobain1992 ... but they are 45 degrees off with the distance scale. It's annoying but even original Takumars with original Pentax adapters can be off; not by 45 degrees but they are off.

03-31-2012, 10:26 AM	#21
vladimiroltean Veteran Member Join Date: Dec 2010 Location: Bucharest, Romania Photos: Gallery Posts: 1,465 Original Poster	Well, none of my M42 lenses were out of whack with the original adapter, including 2 Takumars. I can adjust the Jupiter easily, but I don't know for the others.

03-31-2012, 12:00 PM	#22
excanonfd Veteran Member Join Date: Jan 2010 Location: Vancouver, BC Posts: 1,421	Originally posted by kcobain1992 About a month ago I ordered three flangeless adapters (knockoffs of the original) for $7.50 each from ebay, hoping that I can remove the metal clip and use them to semi-permanently adapt some M42 lenses to K. They arrived today, and unfortunately they are VERY stiff. I mounted them on the lenses, but these do not rotate in the camera's mount more than, say, 5 degrees. As a simple glance, I didn't see any obvious difference between the original Pentax and these, so maybe you can help me solve my problem. I've had the same problem from some of the knockoffs from China, for some strange reason they would not work with any Pentax m42 lenses but work very well and snug with the Soviet and East German lenses. The spacing between the lugs and the flange was slightly less than the original Pentax m42 adapter. If you have a digital caliper, measure the spacing between the flange and the lugs on both adapters. If you don't have a caliper, you can still do it but becomes a bit more tedious (many trial fittings). Using an emery board. gently sand the lugs constantly checking the measurements or you can sand each of the lugs a fixed number of strokes, clean the adapter (soapy water bath, rinse and dry) mount the adapter to a lens then try mounting the lens on a K body camera. Repeat the process until you are satisfied with the fit. The adapters are made of brass and won't need too much sanding to get them to fit properly. I find the original m42 adapter too loose to be used as adapters for a semi-permanent conversion from m42 to K lens. The knockoffs are much better suited for semi permanent M42 to K conversion, if you make some modifications. I have to get a few more myself, when these knockoff adapters are screwed on tight to the m42 lens, where is the red dot in relation to the lens' focus hash mark? Trying to find a seller that has adapters that place the mounting dot close to the focus hash mark is more important than the fit imo. Please provide the name of the seller if the red dot is near the lens focus hash mark.

03-31-2012, 12:45 PM	#23
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,891	Originally posted by kcobain1992 I have partially solved the problem: With lenses with narrow base that does not touch the camera mount, only the adapter (Industar, Helios), the friction is actually OK and helps keep the lens in place (with the Helios, mounting and unmounting is actually smooth). With the other lenses, I had to make circular shims out of paper and place them between the lens mount and the adapter. That way, now they mount smoothly, but they are 45 degrees off with the distance scale. All this means is that you mount the adaptor with the industry lens and then just unscrew that lens and use what you want. I still suggest you look at the spacing between the two flanges though because it seems off

03-31-2012, 01:08 PM	#24
vladimiroltean Veteran Member Join Date: Dec 2010 Location: Bucharest, Romania Photos: Gallery Posts: 1,465 Original Poster	Hi and sorry, not being a native English speaker, some of the terms you used simply overwhelmed me I would like to be of any help, but I need to know what you are referring to by "the lugs", "flange" and "focus hash mark". Here are 2 scans of the adapters, please indicate on them the parts that you mentioned earlier.

03-31-2012, 01:26 PM	#25
excanonfd Veteran Member Join Date: Jan 2010 Location: Vancouver, BC Posts: 1,421	Originally posted by kcobain1992 Hi and sorry, not being a native English speaker, some of the terms you used simply overwhelmed me I would like to be of any help, but I need to know what you are referring to by "the lugs", "flange" and "focus hash mark". Here are 2 scans of the adapters, please indicate on them the parts that you mentioned earlier. Hi, The lugs would the three locking tabs on the adapter that would go inside the K body bayonet mount (2nd picture), the flange is what mates to the m42 lens (1st picture). The focus hash mark is the the focus indicating line on the lens with the DOF markings. If the red dot is within +/- 15 degrees of the hash mark, it would be ideal. Lining up dead on with the hash mark isn't all that good either because of the flash housing beak on the Pentax DSLRs obscures the mark but it's better than having the mark upside down (I've had adapters do that too).

03-31-2012, 04:11 PM	#27
vladimiroltean Veteran Member Join Date: Dec 2010 Location: Bucharest, Romania Photos: Gallery Posts: 1,465 Original Poster	I understand now. Each piece of paper that I add offsets the focus mark by 45 degrees. That would make 8 shims, all at once. I suppose that would affect infinity focus. Actually, I'm just too lazy to cut 8 pieces just to test that. I have thought of it too. There must be a smarter solution though.

03-31-2012, 04:45 PM	#28
k0og Site Supporter Join Date: Nov 2008 Location: Rolla, Missouri Photos: Gallery \| Albums Posts: 699	Kcobain1992, It appears you may have solved your problem, but I'll mention a problem I had with one of my cheap M42 adapters. It would mount on the camera (without a lens), but was a little too tight. As some others have mentioned, it looks like the thickness of the inner flanges in your cheap adapter is more than the original adapter. I filed down the inside surface of the three flanges as shown from your picture: Of course, after filing I thoroughly cleaned all the metal particles from it before trying to mount it in my camera. Now it works as smoothly as an original Pentax adapter. -Joe-

04-01-2012, 03:25 AM	#29
MacRider71 New Member Join Date: Jul 2009 Location: Swansea, NSW, Australia Posts: 21	Which ebay seller did you get those from? I'm looking at buying some and wish to steer away from THAT one! lol

04-01-2012, 05:28 AM	#30
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,891	Originally posted by k0og Kcobain1992, It appears you may have solved your problem, but I'll mention a problem I had with one of my cheap M42 adapters. It would mount on the camera (without a lens), but was a little too tight. As some others have mentioned, it looks like the thickness of the inner flanges in your cheap adapter is more than the original adapter. I filed down the inside surface of the three flanges as shown from your picture: Of course, after filing I thoroughly cleaned all the metal particles from it before trying to mount it in my camera. Now it works as smoothly as an original Pentax adapter. -Joe- Not sure if it is the thickness, or the fact that the thickness has resulted in reducing the space between flanges, but filing that down probably would make things go in easier, however, the OP has also noted that some lenses work better than others suggesting that there is also an issue with the top flange relative to the camera mount. Therefore I think it is also an issue of being able to install the adaptor with some lenses, but once installed, he should be ok