Rough guide to dating an Optimus 8R

Dating an Optimus 8R is part art and part science. Optimus didn't date stamp their stoves and we don't have catalogs for every year but there are a few ways to approximate date of manufacture. The 8R featured a more rounded case than its predecessor "8" and a "self pricking regulating burner" (a needle inside the jet that cleared the orifice and required no manual pricking).

• The 1959 catalog mentions the 8R for the first time. The 8 is also featured on the same page so this was obviously a transition year.
• There are examples of the new rounded case marked "8". The 8 was often covered with an Optimus sticker when the stove was actually an 8R. @Northman has a fine example seen here. https://classiccampstoves.com/threads/my-precious.27151/
• The 8 model featured a nickel plated tank and one theory is that the first 8Rs utilized the last of those nickel tanks. That would logically explain why early 8Rs tanks can be found in nickel and in brass.
• Photos below illustrate some parts changes over the years. There are other subtle changes not represented here but I'm focused on more significant changes.

• "A" I would date this early 60's (1959?). Nickel tank, Optimus embossed case, poker chip style bakelite spindle wheel. Case has carry handle and SRV is slotted type.
• "B" Mid to late 60's based on slotted SRV, poker chip spindle wheel, handled case, burner clip and less decorative embossing on case. I'm deducing the era from what we know about stove A and C. No catalogs in library to verify but seems logical.
• "C" Early 70's. The 1972 Optimus catalog features the 8R with a puck style bakelite spindle, no embossing, no handle and a hex style SRV.
• "D" Late 70's - early 90's. The 1978 Optimus catalog features the stove with a key/tool and no bakelite wheel. They also have warning stickers on them.
• The 1989 Optimus catalog is the last year in the library and the 8R was discontinued sometime in the 90's.

I'm not an expert on his subject and would love others to add content or correct me if I'm off base. Just thought I'd share what I've uncovered in my own personal research and help others date their own 8Rs. Cheers, Jerry

 

Well done, Jerry.

 

An excellent post.

 

Hi @Metropolitantrout . A useful post and nice photographs.

You say:

“The 8 model featured a nickel plated tank and one theory is that the first 8Rs utilized the last of those nickel tanks. That would logically explain why early 8Rs tanks can be found in nickel and in brass.”


However, the tanks of the Optimus 8 and 8R are different, in particular the position of the fuel outlet from the tank.

In this post:

https://classiccampstoves.com/threads/pre-ptc-optimus-8s-8rs.15470/

Bryan Miller said:

“The stoves are very easy to identify although the differences do not show on these photos.

The fuel pipe on an 8 comes from the centre of the tank. The nipple is the same size as a conventional nipple and needs a pricker to clean it. The regulating spindle is small.

The fuel pipe on an 8R comes from slightly left of centre of the tank when facing it from the front. The nipple is enlarged to accommodate an internal cleaning needle. The regulating spindle is large with an enlarged housing on the burner to accommodate the cleaning needle”

Best Regards,
Kerophile.

 

I have two 8R.
The first one is has burner clip. The box has handle, but is not embossed. And it has what you call puck style spindle. So it is somewhere between your B and C.
The second one is with the 123R-tool-key, no handle and no burner clip. The cardboard is the one that was used in the seventies, and is stamped '885074' and the manual is marked 'Märstatryck 74-6188'. So I guess it is from 1974.

 

Excellent post. Thanks for your research, very useful.

Paul

 

@kerophile
You are absolutely right, the tanks are not configured the same so that theory is proven false. Perhaps the earlier tanks were nickel to help keep the look consistent during transition?

Anyway, great catch thanks! Jerry

@afoton
Thanks for posting. Good example of how these stoves evolved. I'm not sure about the instructions but '74 seems logical.

 

@Metropolitantrout

This is a great thread, Jerry. A fine example of using collective knowledge to sort out problems.

Thank you.

Cheers

Tony

 

So, and 8R is not just an 8R.
Interesting data collection.
A, B, C, D. Now a B/C. Nice work.

 

On my 8R in 8 box with nickel tank there is indeed no doubt that it was designed with the tank outlet off-center. The slot in the heat shield is pretty wide though and it would allow for both centre and off-center connections.

 

I think all 8R-heatshields have the wide slot so they will fit both 8 and 8R.

 

Ah, OK,

My 8 has a small slot so to me it is quite surprising that they chose an universal wider slot later for the 8R and subsequently discontinued the 8. Maybe there was some additional benefit to the wider heat shield slot. Anyway, that's a different discussion altogether.

 

My 8 litter has expanded to four. Thank you for your research. The top is an old 8 and the right is a new-in-the-box “D” era by your research. The one on the left falls solidly in your “B” category. It has been heavily used and looks to be repainted. My latest acquisition, on the bottom, seems to fall between your “B” and “C” category but is more in the “C” era. The case has the features of the ”B” but the internals of your “C” category. Sorry, the second picture got turned. I was wondering their ages and this helps narrow it down.

 

@MartyJ
I like your #8 especially. Also thanks for the photo of your 8R at the bottom. It shows a spindle with "clean and close" but no Optimus and no Made in Sweden. Yet another variance.

Agreed! The supporting contributions make for a better thread. Jerry

 

Thanks Jerry,
The 8 is in good shape but it is missing the wrench and key. It has a clock key someone has crushed down to work but I will find a replacement someday. The box has no dents and very light rust as you can see. It was a lucky find in Norther Oregon and I would imagine has been on some epic trips.

The repainted stove has seen some miles too but is a working stove and I appreciate the wear and tear.

The most useless to me is the unfired. I don’t need to use it so won’t and will likely trade it someday for something I crave.

The B/C is a nice stove. I just got itbut needto fire and order off to Fettlebox, I have fond so many stoves this Summer I have used up my supply of filler cap gaskets and that one is dried out. O to have such troubles. Marty

 

I bought my first 8R in 1975 and it had the metal key. Excellent article. Thank you.
Cheers
Simon Foxxx
New Zealand

 

I noticed while i had 2 ,of them A andD models the burner bell was different too the early one has the threaded part below the bell the later one the bell rested against the control valve and the threaded portion was inside the bell i kept the old model and moved the newer one to a new owner

 

Dude, well done.
My stove fits everything of "C" but it has a handle.

 

Thanks @Metropolitantrout for the research! I was able to date mine both as D type stoves.