NickTrop
Veteran
I am not a camera repair guy but I HATED 
putting that #%$# M42-Pentax-K adapter ring off-n-on my K-mount SLR when I wanted to use K lenses. Love the M42 lenses (most of them anyway) - hate the M42 adapter ring.
I read some instructions on the net about how to convert these lenses permanently to Pentax K - so I did two over the weekend: an 85/2 Jupiter 9 and 50/1.4 Super Takumar. Two of my favorite lenses.
The process entails:
1. Removing the spring clip on the adapter ring
2. Screwing the "adapted" adapter ring to the rear of the lens
3. Then cutting a notch in the rear of the lens where it "locks" to the camera body.
Read a few posts here and there of people who are loathe to do this. But it was easy as pie. "Official Instructions" use a drill to make the notch but I used a small file - worked like a champ.
So, so, so much nicer just clicking these lenses in and out like a "regular" Pentax K mount lens. I used the Roxen adapters which focus to infinity - a bit more expensive but I highly recommend.
putting that #%$# M42-Pentax-K adapter ring off-n-on my K-mount SLR when I wanted to use K lenses. Love the M42 lenses (most of them anyway) - hate the M42 adapter ring. I read some instructions on the net about how to convert these lenses permanently to Pentax K - so I did two over the weekend: an 85/2 Jupiter 9 and 50/1.4 Super Takumar. Two of my favorite lenses.
The process entails:
1. Removing the spring clip on the adapter ring
2. Screwing the "adapted" adapter ring to the rear of the lens
3. Then cutting a notch in the rear of the lens
where it "locks" to the camera body. Read a few posts here and there of people who are loathe to do this. But it was easy as pie. "Official Instructions" use a drill to make the notch but I used a small file - worked like a champ.
So, so, so much nicer just clicking these lenses in and out like a "regular" Pentax K mount lens.
I used the Roxen adapters which focus to infinity - a bit more expensive but I highly recommend.Nando
Well-known
Hi Nick,
I want to do this! Can you provide a link to the instructions that you followed?
I want to do this! Can you provide a link to the instructions that you followed?
NickTrop
Veteran
Hi Nando -
I can't find the link (read it a while ago) but it's pretty self-explanatory. Buy a Roxen M42 to K adapter. Not sure how familiar you are with these, commonly available on eBay. I had one and ordered one recently, came very quickly from Hong Kong. They're a little pricey for what they are - around $20 US shipped, I think. I suggest these because they focus to infinity and the screw on the outside of the adapter that holds the adapter's clip is very easy to remove.
On the outside of the adapter is a small clip held on with a tiny Phillips screw. Remove this clip. Next, screw the adapter to the rear of the lens. Put it on the camera, and carefully note where the pin from the K-mount camera meets the lens. It was on the "edge" (you'll see what I mean) of the rear of the lens. With a thin file (I had the lens carefully set in a vice) as carefully and accurately as possible file a notch in the lens where the locking pin connects with the rear of the lens. File, try to attach the lens, file, repeat until it "clicks" into place like a regular K-mount lens. Be careful to blow away metal shavings so they don't make their way into the lens.
If you have a Pentax K mount lens, just study how it connects to the camera and emulate that on the M42 lens with the adapter. I found it to be really easy, and am glad I did this. Took about 1/2 hour tops per lens start to finish.
If you need additional help, PM me and I'll walk you through it as best I can. But it's easy to figure out what you need to do simply by noticing how K-mount lenses are secured. The key is to remove the clip on the adapter.
Trust me... If Nicky "All Thumbs" Trop----o can do it, anyone can
I can't find the link (read it a while ago) but it's pretty self-explanatory. Buy a Roxen M42 to K adapter. Not sure how familiar you are with these, commonly available on eBay. I had one and ordered one recently, came very quickly from Hong Kong. They're a little pricey for what they are - around $20 US shipped, I think. I suggest these because they focus to infinity and the screw on the outside of the adapter that holds the adapter's clip is very easy to remove.
On the outside of the adapter is a small clip held on with a tiny Phillips screw. Remove this clip. Next, screw the adapter to the rear of the lens. Put it on the camera, and carefully note where the pin from the K-mount camera meets the lens. It was on the "edge" (you'll see what I mean) of the rear of the lens. With a thin file (I had the lens carefully set in a vice) as carefully and accurately as possible file a notch in the lens where the locking pin connects with the rear of the lens. File, try to attach the lens, file, repeat until it "clicks" into place like a regular K-mount lens. Be careful to blow away metal shavings so they don't make their way into the lens.
If you have a Pentax K mount lens, just study how it connects to the camera and emulate that on the M42 lens with the adapter. I found it to be really easy, and am glad I did this. Took about 1/2 hour tops per lens start to finish.
If you need additional help, PM me and I'll walk you through it as best I can. But it's easy to figure out what you need to do simply by noticing how K-mount lenses are secured. The key is to remove the clip on the adapter.
Trust me... If Nicky "All Thumbs" Trop----o can do it, anyone can
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Nando
Well-known
Thanks Nick.
I examined the notch on my K-mount lenses and it seems easy to duplicate on my m42 lenses. Just be looking at the two types of lenses and examining the mount, one can easily figure out what must be done. The part I'm worried about is making sure that the notch is in the correct location. I put the adapter on an m42 lens and mounted it my Pentax MX. I found it a bit cumbersome to mark the exact spot where the notch should be as my m42 lenses are quite large and the diameter of their barrels are wider than the K-mount. (Helios 85/1,5 and CZJ 300/4) Perhaps its a good excuse to hunt down the smaller CZJ 20/2.8 or 35/2.5 that I've been wanting.
I examined the notch on my K-mount lenses and it seems easy to duplicate on my m42 lenses. Just be looking at the two types of lenses and examining the mount, one can easily figure out what must be done. The part I'm worried about is making sure that the notch is in the correct location. I put the adapter on an m42 lens and mounted it my Pentax MX. I found it a bit cumbersome to mark the exact spot where the notch should be as my m42 lenses are quite large and the diameter of their barrels are wider than the K-mount. (Helios 85/1,5 and CZJ 300/4) Perhaps its a good excuse to hunt down the smaller CZJ 20/2.8 or 35/2.5 that I've been wanting.
Kim Coxon
Moderator
Mount the adapter with the lens on. Then unscrew the lens leaving the mount behind and it should be easy to mark.
Kim
Kim
Nando said:Thanks Nick.
I examined the notch on my K-mount lenses and it seems easy to duplicate on my m42 lenses. Just be looking at the two types of lenses and examining the mount, one can easily figure out what must be done. The part I'm worried about is making sure that the notch is in the correct location. I put the adapter on an m42 lens and mounted it my Pentax MX. I found it a bit cumbersome to mark the exact spot where the notch should be as my m42 lenses are quite large and the diameter of their barrels are wider than the K-mount. (Helios 85/1,5 and CZJ 300/4) Perhaps its a good excuse to hunt down the smaller CZJ 20/2.8 or 35/2.5 that I've been wanting.
NickTrop
Veteran
Kim Coxon said:Mount the adapter with the lens on. Then unscrew the lens leaving the mount behind and it should be easy to mark.
Kim
Duh... Wish I'd a thunk of that. Thanks Kim.
Sorry for bumping my own thread - bad etiquette and all that, but a few PM'd me about this and was wondering if anyone tried this and were successful. Nando?
If you have M42 to Pentax K this is bliss. That adapter is a royal pain in the arse. I'm using these lenses much more - w/o reservation, because of this successful (and fairly simple) outpatient surgery.
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