What Type Of Steel Are Maico Frames

[Ji Gantor]

I have some fragments from the last Maico frame I had to repair.
The fragments came from the tube frame, a distance from weldments.
I have found a company here in Brisbane that will do a spectrometer chemical analysis on the fragments for $150.00 plus GST.
The test will take three days.
The sample will be distroyed during the tests.
This info will lead to better understanding on heat treatments and welding processes.

I am prepared to pay the money to find out once and for all what kind of steel Maico's are made from.
My questions are;
a) Is there another company or university that will perform a similar test for a lesser charge?
b) Does anyone know what metal did Maico use in their frames?

Thanks Ji
 

[Ji Gantor]

Fragments from Maico frame.

Ji

[GMC]

The results would be interesting but it won’t really change anything.
Keep in mind that I haven’t said the frames aren’t chrome-moly, just that I don’t believe they are the aircraft grade 4130.
I still repair frames with ER90 and I still believe in heat treating the frames to stress relieve them anyway.
It’s a lot of money to pay just to settle a debate.


If your still keen I can send you a piece of 4130 for them to compare, unless they want to charge you double.
The specs of 4130 would be around somewhere.
If you want a piece of 4130 let me know what size offcut you would need.

[Ji Gantor]

Hi GMC,
This topic is not a platform to dilute one word you have said on the subject, in fact I want to prove what you have said is correct.
I am on your side.
Every thing you have said about Maico frames and how to weld them up is the best source of information I have ever read.
The tip about drilling a small hole into closed tubes is pure gold, but I am sure others will not even understand what you are going on about.

Chrome moly welding is a vast subject and most frame repairs are carried out incorrectly.
This is because of cost, lack of know how, cost of tooling or ........
If we know what type of steel Maico used this will help us make the right decisions.
Pre heating, Post heating and Filler rod.
The temps and times required for heating process.

I know the average guy is not going to do any of these things, but it may make a few think twice next time their frames need welding.

Ji

[Ji Gantor]

Unfortunately Geoff they will charge double.
They are cheap though I did get an estimate of $550.00 plus GST from another company.

What size sample would I like, how much will Australia post carry, 20Kgs is it not.   LOL

Thanks mate
I am a compulsive and I just need to know.
Next if I can get a sample will be a CZ frame.

Ji

[vmx42]

They say you get the Nobel Prize for the question [not the answer] so who knows where this could lead?

I gotta say Ji, your enthusiasm is truly legendary. Just make sure you only use it for good, not evil!!

…the tip about drilling a small hole into closed tubes is pure gold, but I am sure others will not even understand what you are going on about

…not sure about that. Even humble graphic designers were aware of it  

[Ray Kricker]

Maico frames are made from old Meschersmits aren't they?

[Lozza]

4130 is SAE standard for CrMo Euro standards are a bit different, it could well turn out to be something like 25CrMo4 which was first used and developed by Fokkker for their airframes.Perhaps the later spec 15CDV6 which is CrMo +Vanadium
With the analysis of the various % alloying elements, I would be sure my reference books could match up to what steel alloy it is.

[Ji Gantor]

Chrome Moly or CrMo is a steel.
There are heaps of different types of CrMo.
I don't know the standard types available for sale back in the sixties and seventies in Germany.
The chemistry or metallurgical content of CrMo can be determined and then a standard available grade name will be assigned.
Every one always talks about 4130 but this is not the only CrMo out there.
4130 was and still is used in the aerospace industry.
The CrMo that may have been used in Maico frames may be some really diluted grade that had a tensile strength just above mild steel.

I think from my experiences that Maico frames were Oxy welded. This process heats the tubes slowly and if done right prevents the welds from cracking. TIG welding cools much faster than Oxy and heat treatments are required for the best job.

I checked the temp of a tube I welded yesterday after putting the torch down and picking up the thermometer, the temp had dropped down to 215 degs C. Within an hour with no post heat treatment the tube had returned to ambient. Without pre heating and post heating treatments CrMo welds will crack.

Ji

[GMC]

Hi Ji, I wasn't suggesting there was any angst, just that curiosity can kill the bank account.

I had thought about doing this myself years ago and the figure of $150 was bandied about. In the end I couldn’t justify the cost, as I said, I treat original frames the same as if they were 4130 anyway.
From working will both original frames and 4130 tubing I get the impression that most original frames are a bit softer.
I remember guys saying in the 70’s to be careful with Husky frames as they had been heat treated, so they would be another good one to test. Again curiosity can get expensive.

Keep in mind too that the results will probably be a breakdown of the elements found. More research would then be needed to classify the grade of steel these elements represent.
You should run this past them if organizing a test.

[Ji Gantor]

Hi Geoff,
The company that will perform the test will check all the elements and assign a steel grade that is the best fit.
This is part of their product.
They will only assign an Australian steel grade so I may need Lozza (I mean who doesn't)


Ji

[Ji Gantor]

The company will also provide the best way to weld it including pre and post heat treatments.
This must be out of some Australian Standard or NATA I would think.

Ji

[Ji Gantor]

I would like to take this post to thank all the very helpful, talented, kind, expert and unassuming members of this forum that PM or Email me with their offers of help and enthusiasm. Without you Saints this place would be very boring and one sided.
I hope to see more of you at CD7 so I can thank you personally.

Many Thanks
Ji

[EML]

So Mr Jigantor and co. I wish to make a copy of Geoff Udys DR500 sidecar outfit that was made by Nugents in Toowoomba form the same alloy as bulbars of the time.
I remember Dave Nugent saying that the alloy would ''self anneal'' after being bent and it would not need heating to relieve the stress. the only cracks we had were after hitting a tree amidships at an off raod enduro type event when pilot to co-pilot communications we on the blink momentarily.( this was quickly rectified with some SHOUTING TO RENEW CONTACT)
So whilst remaking said sidecar should I heat treat the welded areas or leave it to chance.
I think it was also the reason he went up 1 size in tube diameter, to give it extra strenght, so are the tube strenghts the same now or perhaps improved?.
The frame will just be mig welded by the way, unless you can recommend otherwise.

[Ji Gantor]

This is the whole point of this thread Mr EML.
If you don't know what steel you are using it is hard to make any real suggestions.
If you have that original frame take some samples and have it tested, but I know no one is going to do that, so were does that leave us.
If you are going to use CrMo 4130 that should do the job well and there is plenty of info on how to weld it on the web.

The reason race car teams select CrMo for the roll cage is to reduce weight not for extra strength. This is the reason why NASCAR don't require teams to heat treat their roll cages.
They are allowed to use mild steel if they like but it weighs to much.
Tube design is very interesting, if you go up a diameter you can reduce the wall thickness to a point thus making a stronger frame for less or same weight.

Ji