Topic: DIY titanium 4into1

[mec]

hi,

inspired by some nice pics and exhaust systems, i felt the wish to have something similar on my egli racer.
after some search in google i was pretty sure that there was a chance to get all the parts i needed for this project. there seems to be a big difference between europe and overseas. while its easy to find titanium tubes, sheet metall and the welding components in the US, it can be a pain to find all the sources here in europe (the typeB solar flux i bought in ebay for 49$ from US, was offered here in austria for 116€!!). the same is reality for all the titanium stuff.

my sources:
titanium tube bends (tube 40x1.2) for the headers according to my drawings from MAB Power (mab-power.de). tube 50.8x0.89mm the pipe after the collector.
1.6 and 1mm titanium welding rods from weldingtool.de and ebay
type B solar flux ebay, here in my town ethanol for mixing the powder
titanium sheet metall ebay

lets do some investigations to make things a little bit clearer:
first i did simple drawings in corel to understand better the geometrical situation in a merge collector. to show further details i made one collector out of simple plastic waste pipe, welded together with soldering iron. this modell showed where there will be difficulties welding together all the pipes. not easy, but doable.

the existing exhaust system seems to be a kerker system. all in all there was not much to complain about this setup, exept the old heavy used look and the weight.

it was easy to bring the contours of header one and two to paper. 3 and 4 a mirror of 1,2. because of the 2 dimensional drawing it was clear that the new ti-headers will not fit a collector with 4 parallel inlets. i expected have to make some changes to pipe 1 and 4. these drawings had been sent to mab-power with the order to have made these pipes out of 40x1.2mm titanium tube.
2 or 3 weeks after order the pipes arrived. all bends perfect. for the collector i ordered 6 bend pipes (17.5°), 2 pipes to play with, because i was unsure what will go wrong. my order included to have made all the necessay tube expansions. but there went something wrong, i had to do all the expansions by my own, learning by doing.

mec

[mec]

picture on the lathe shows one of the +40mm expander. with my press i did two test expansions. both worked fine. to pull out the expander from the tubing i made an "pull puller", working with the weight of the brass. it worked fine for the first expansion but i could not get out the expander from the second test expansion (despite using a lot of oil for the process), no way. i cut the tube into two had to make another expander dowel and learned my lesson. next step was to fabricate a better working puller tool: easy to do but again 2 hours on the lathe. this time the puller was activated by an M10 screw with an M10 nut. this tool worked perfect.

next thing to learn the hard way: to do the expansions (and to mill the tube ends) i had to clamp the headers either on the press or on the mill. a scrap of hard aluminium was turned down and cut into two halfes (with to M8 threads to clamp). remember, aluminium is good for many things, but not for making tools. this clamp was not able to hold the tubes during the expansion dowels beeing forced into the tubes by the press. contrary the later machined tool made out of steel. double work, learned again, at least till the next alzheimer attack .
to be continued.

mec

[lucky]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

[Retro Rocket]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

Lucky, you need to be a little more forgiving mate, Mec is European and there a little details lost in translation, this guy is a master craftsman, he REALLY knows his stuff.  It may serve you well to check out his Egli replica build, he basically built everything himself including the awesome frame.....

[lucky]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

Lucky, you need to be a little more forgiving mate, Mec is European and there a little details lost in translation, this guy is a master craftsman, he REALLY knows his stuff.  It may serve you well to check out his Egli replica build, he basically built everything himself including the awesome frame.....

Will do.

[Don R]

I've heard of tig welding Ti in a box filled with argon. It is heavier than air and acts like water. I'm wondering about an internal gas purge while tig welding the outside. I've done that with food grade stainless. We taped the ends of the tube to keep air out, poked a small hole for flow and purged with argon while welding.
 Watching with intrest.

[mec]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

@lucky
thx for correction. please can you explain the difference between "tubes" and "pipes".

all the welding will be done by TIG.

mec

[crazymofo]

be sure to back purge the tube/pipe with argon (tape up the open ends and have bottle of argon gas with a line in to fill the inside of the tube/pipe as you weld).... a much cleaner result will show.

cheers.joe.

[Bankerdanny]

@lucky: I'm with mec, I don't understand the distinction you are making.

A tube is a pipe and a pipe is a tube. In terms of vernacular tubes are pipes used for some sort of structure while a pipe is used to route a liquid or a gas, thus frame tube and exhaust pipe.

But either way both are geometrically tubular.

[Spiider]

Tube is normally dimensioned from the inside...pipe is normally dimensioned from the outside.

So a 40mm tube has an inside diameter (ID) of 40mm.
A 40mm pipe has an outside diameter (OD) of 40mm, minus your wall thickness gives you the ID.

Edit: Nice job Mec! I'd love to have half your expertise.

[Tews19]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

Lucky, you need to be a little more forgiving mate, Mec is European and there a little details lost in translation, this guy is a master craftsman, he REALLY knows his stuff.  It may serve you well to check out his Egli replica build, he basically built everything himself including the awesome frame.....

LINK PLEASE! sounds very cool!!!!!!!!!!!!!!!

[Retro Rocket]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

Lucky, you need to be a little more forgiving mate, Mec is European and there a little details lost in translation, this guy is a master craftsman, he REALLY knows his stuff.  It may serve you well to check out his Egli replica build, he basically built everything himself including the awesome frame.....

LINK PLEASE! sounds very cool!!!!!!!!!!!!!!!

For those that haven't seen it .....

http://forums.sohc4.net/index.php?topic=44736.0

[Tews19]

Thanks RR

[mec]

hi,

@crazymofo: thx for your help.

after i did some investigations on "merge collector", "how to weld titanium" and so on, the real work began:
first photo shows a spare tube doing some practice welds. titanium is easy to weld. but: you have to provide against oxygen coming into contact with the material during the welding process and you must not exceed a certain welding temperatur (a blue color is the critical temp). either you shield the seams with a backup flux, or better you work with additional back purging argon gas. the characteristic shape of the collector made the solar flux necessary. i did not see any way to back purge the collector. the weld of the 50.1mm tube to the collector was done with back purging however.


next photo shows how i fixed the thin walled tubes on the mill. with pliers i stuck a digital protractor to the tube, in order to set the tube 45° for milling. this way i milled 4 bend tubes for the merge collector. two of them had been TIG welded together, the pairs welded together as well. all these welds had been shielded by my "solar flux typeB" backup flux. this comes as a powder which has to be mixed with (m)ethanol to become a paste. two seams within the collector couldnt be reached from the outside. i plugged the 4 tubes of the collector, filled it with argon gas (argon is heavier than air), elongated the wolfram electrode 3.5cm (!!) over the ceramic shell and tried to weld the inside pyramide. what a wonder, it worked fine.

mec

[mec]

during work one of the vise broke into two. no heavy load, i wanted to clamp the thin walled tubes! made out of good wood, would be as strong
here some photos:

mec

[70CB750]

Impressive work!  What mill do you have?

[mec]

mill is a really small one: wabeco F1210, see: https://www.wabeco-remscheid.de/index.php?cat=c14010_F1210.html

nevertheless the mill was good for boring the cylinders and crankcase. furthermore surface milling the cyl head, milling the maintube for the steering tube (see my egli replica thread).

mec

[HonderCB]

mec, i am thoroughly convinced that you are some sort of super-human.

Nice work!

[Tews19]

How come you don't have a TV show? Or been asked to be on something like Cafe Racer? Sorry for my ignorance if you do or have been approached, but this thread has giving me links to your other work and I have not seen anything like it. Great work.... Interested in making a set of pipes for members?

Tews

[70CB750]

I am thinking about getting a mill. Likely G0704 from grizzly

[lucky]

That is a interesting project.
So what welding process are you using?
Not clear. Are you intending to braze with a dissimilar metal?

BTW...Those are tubes not pipes.

@lucky
thx for correction. please can you explain the difference between "tubes" and "pipes".

all the welding will be done by TIG.

mec

Happy to explain.

A TUBE is measured by the OD (outside diameter), and is usually with in .002 thousandths. About the thickness of a human hair.

A PIPE is measured by the inside diameter and can be + or - .025 thousandths!
A pipe comes in schedules . A schedule 40 for instance could be 3/4 inside pipe but the outside would be .113 thousandths, a very thick pipe.

This is the reason tubing is used for auto and motorcycle projects is because it is more precision measurement, and some sizes will fit inside of each other with a slip fit.

A tube is made from sheet metal that is rolled /formed into a tube shape.

[754]

Tews, I guess its not on his avatar..but Mec is in Switzerland.
 And he has something cooler than aLL YOU HAVE SEEN..yet.. at least to me... a 101 Scout...

[Retro Rocket]

Tews, I guess its not on his avatar..but Mec is in Switzerland.
 And he has something cooler than aLL YOU HAVE SEEN..yet.. at least to me... a 101 Scout...

I thought Mec was from Austria....

[754]

 ACH du Scheiz!!    Austria it is,, .. I thnkthat is a canton of Switzerland...lol..

[70CB750]

mill is a really small one: wabeco F1210, see: https://www.wabeco-remscheid.de/index.php?cat=c14010_F1210.html

nevertheless the mill was good for boring the cylinders and crankcase. furthermore surface milling the cyl head, milling the maintube for the steering tube (see my egli replica thread).

mec

I was using iphone, didn't get to the link, but that's a good looking mill you have there - and Made in Germany is an extra bonus, IMHO.