Rosebud machinegunning

[Charliekilo]

I was trying to bend a piece of 1 in. re bar for a project and the rosebud would start backfiring. I cleaned it and start over and when the re bar started to glow it would start backfiring. Any ideas what i am doing wrong?

 

[jsaw]

Maybe holding it too close to the workpiece.

 

[rkevins]

what settings to you have your guages? I think they need to be the same ( but have'nt used one in a long time)

 

[Stick]

Popping is usually a sign that the mixture is too lean. A couple of possibilities: wrong gas pressures, wrong type of flame, tip is getting too hot, tip is too close to the workpiece, etc.

As a general guideline for torch tips, O2 should be 5x the fuel gas. I usually break that rule when running a rosebud, with 15psiAce & 40psiO2, but we've got pretty big tanks at work. The flame should be set as a carburizing flame (slightly on the rich side) in order to help keep the tip cooler. You also don't want to hold the tip at a 90 degree angle to the workpiece, try between 45 and 60 degrees.

Edit: also make sure you have backflow preventers installed on the torch, just for safety.

 

[slip knot]

I was told once that the smaller bottles wont run a big rosebud tip. Something to do with the smaller acetyline tanks wont make gas fast enough to feed the tip. Could be the guy was FOS ?

 

[machine_punk]

I was told once that the smaller bottles wont run a big rosebud tip. Something to do with the smaller acetyline tanks wont make gas fast enough to feed the tip. Could be the guy was FOS ?

It is true that you cannot add, or remove, more than 1/7 of the acetylene from the bottle each hour. It takes time for it to dissolve out and mix into the acetone in the bottle.

So, larger flow rates do require larger bottles.

 

[Charliekilo]

Thanks for the tips guys. Stick I have never heard of back flow preventers care to enlighten?

 

[NUTTSGT]

Thanks for the tips guys. Stick I have never heard of back flow preventers care to enlighten?

Basically a one way valve, gas can leave the bottle but not go back in. . . . including flame.

 

[StumpXJ]

It takes a big tank to properly run a rosebud of any size for any length of time, you likely dont have a big enough tank, causing the popping due to incorrect mixture.

What number tip do you have? What size Accety tank?

 

[sberry]

Low fuel pressure/volume for sure, if the tank can support it turn the fuel pressure up, if not you need a bigger cylinder.

 

[welder4956]

As StumpXJ suggested, the oxygen and acetylene pressure settings depend on the tip size. You need to look at the markings on the tip and determine who made it and what size it is. Once you know that, you can look at the manufacturer's tip chart to see what settings work best. Don't expect a 1/4" hose to flow enough gas to feed a #8 or larger rosebud. As mentioned previously, don't exceed a withdrawal rate of 1/7 of the acetylene cylinder per hour or you will be flowing liquid acetone through the hose.

Here is an example of a tip chart. Scroll down till you see the settings for Heating Tips.

http://www.hoopersupply.com/tipchart.html

 

[Charliekilo]

It takes a big tank to properly run a rosebud of any size for any length of time, you likely dont have a big enough tank, causing the popping due to incorrect mixture.

What number tip do you have? What size Accety tank?

The rosebud is a Victor 8-129 and the tank is a 110 cf. The rig is Victor 100 series.
Hope that helps
C

 

[welder4956]

The rosebud is a Victor 8-129 and the tank is a 110 cf. The rig is Victor 100 series.
Hope that helps
C

That would be a #8 heating tip. About 13 psi acetylene and 25 psi oxygen should be good. Light off with the acetylene only with enough flow to get rid of the soot floating in the air. Slowly add O2 and then add acetylene, then more O2 and more acetylene till you get a good neutral flame.

 

[Charliekilo]

That would be a #8 heating tip. About 13 psi acetylene and 25 psi oxygen should be good. Light off with the acetylene only with enough flow to get rid of the soot floating in the air. Slowly add O2 and then add acetylene, then more O2 and more acetylene till you get a good neutral flame.

Thanks. Now I have to try again today.
thanks again
C

 

[MoonRise]

RTFM.

Right from the Victor "Torch Handles, Cutting Attachments, and Heating Nozzles: Safety and Operating Instructions" (Form No. 0056-0138, Revision:C, Issue Date: May 14 , 2008) from the Victor/Thermadyne website (or call Victor/Thermadyne at 800-426-1888 in the US). Page 20-21 (page labeled 6-16 to 7-17):

"Multi-Flame Heating Nozzles (Rosebuds)
Multi-flame heating nozzles are set up exactly as the welding nozzle.
Follow the safety and operation procedures described above for the
welding nozzle.

CAUTION
Never starve or choke a welding nozzle or multi-flame heating
nozzle. This causes overheating of the nozzle and a backfire or
sustained backfire may result. Should a sustained backfire occur
(flame pops and disappears and/or a hissing sound is heard, the
flame is burning inside the nozzle), immediately turn off the oxygen
valve on the torch handle. Then, turn off the fuel valve. Allow the
nozzle to cool before using it. If a backfire reoccurs, have the
apparatus checked by a qualified technician before using again."

Also, Section 7 - Specifications , page 7-18 , MFA Heating Nozzles :

#8 nozzle, parameters chart says

acetylene = 10-15 psi
oxygen = 20-30 psi
acetylene flow rate: min= 30 CFH, max = 80 CFH
oxygen flow rate : min = 33 CFH, max = 88 CFH

WARNING NOTE:

"At no time should the withdrawal rate of an individual acetylene cylinder exceed
1/7 of the cylinder contents per hour. If additional flow capacity is required, use an
acetylene manifold system of sufficient size to supply the necessary volume."

You are 'starving' the tip and drawing an excess flowrate of acetylene from your 110 ft3 acetylene tank.

Soooo,


STOP!

Warning Wiil Robinson, danger, danger, danger. Excess acetylene flowrate for the tank size through a 'too big' rosebud heating nozzle, not KNOWING what a flashback/backflow arrestor is., not looking up the info in the freely available information right from the manufacturer's website or multiple other sources on the net about parameters and flow rates for acetylene including the safety information about not flowing more than 1/7 the acetylene tank size per hour flowrate, etc, etc.

Please STOP.

"CAUTION
Check valves are mechanical devices that can leak when dirty
or if abused. Check valves should be tested at least every six
months, more often if hoses are frequently disconnected. Careless
usage, dirt or abuse can shorten the service life of check valves,
thus requiring more frequent testing. Follow the manufacturer’s
instructions for testing the check valves.
NOTE
Reverse flow check valves are not the same as flashback arrestors.
Check valves are designed to help prevent reverse flow of gas
upstream of the torch. Flashback arrestors are designed to prevent
mixed gases from igniting upstream of the flashback arrestors.
5.02 Flashback Arrestors
NOTE
VICTOR® torch handle model numbers that contain the letters
“FC” are equipped with built-in flashback arrestors and check
valves (i.e. 315FC). Model numbers with a “C” only contain built-in
check valves (i.e. 315C). Earlier versions without an “F” or “C” in
the model number contained neither (i.e. 315). For all “C” model
torch handles and earlier versions, it is recommended that add-on
flashback arrestors be installed. Most add-on flashback arrestors
also contain built-in check valves.
Most VICTOR® torch handles are equipped with built-in flashback arrestors.
Flashback arrestors are designed to prevent mixed gases from igniting
upstream of the flashback arrestors.
CAUTION
It is not recommended to use accessory flashback arrestors on
VICTOR® FC torch handles since these devices are already built-in.
Excessive flow restrictions may occur.
The flashback arrestors contained in this torch are designed to prevent a
flashback flame from entering the hose and gas supply system. A very fine
“filter-like” sintered stainless steel flame barrier stops flashback flame.
For maximum service life of the flashback arrestor, completely purge
all lines and hoses before connecting to the torch. This removes loose
material contained in the hose or regulator that could restrict flow through
the flashback arrestor.
Flow restriction and torch overheating results if dirt or “oily” LPG residuals
are allowed to flow into the flashback arrestor and cause clogging. Make
sure not to draw liquid.
Always store and use cylinders in the upright position."

 

[welder4956]

Also, Section 7 - Specifications , page 7-18 , MFA Heating Nozzles :

#8 nozzle, parameters chart says

acetylene = 10-15 psi
oxygen = 20-30 psi
acetylene flow rate: min= 30 CFH, max = 80 CFH
oxygen flow rate : min = 33 CFH, max = 88 CFH

WARNING NOTE:

"At no time should the withdrawal rate of an individual acetylene cylinder exceed
1/7 of the cylinder contents per hour. If additional flow capacity is required, use an
acetylene manifold system of sufficient size to supply the necessary volume."

You are 'starving' the tip and drawing an excess flowrate of acetylene from your 110 ft3 acetylene tank.

A good point which I overlooked. At the lowest regulator setting of 10 psig for a #8 tip, the flow rate would be 30 CFH/hr. 1/7 of a 110 ft3 cyclinder is 15.7 ft3, so you need a tip that does not require more than 15.7 CFH, or you need a bigger cylinder volume. A 250 ft3 cylinder would be safe up to 35.7 CFH flow rate, which is the lower end of the range for a #8.

 

[Kevin54]

CAUTION
Never starve or choke a welding nozzle or multi-flame heating
nozzle. This causes overheating of the nozzle and a backfire or
sustained backfire may result. Should a sustained backfire occur
(flame pops and disappears and/or a hissing sound is heard, the
flame is burning inside the nozzle), immediately turn off the oxygen
valve on the torch handle. Then, turn off the fuel valve. Allow the
nozzle to cool before using it. If a backfire reoccurs, have the
apparatus checked by a qualified technician before using again."

Most shops now require torches with a backflow preventer. The one at our shop doesn't have it, or didn't. I never saw more people that would light a rosebud only to have it pop and whistle. The tip all the way down the torch get really hot when it does that.

When I light the rosebud, I always crack the oxygen and acetylene both open the same amount on the torch. I'll crack each knob 1/4 to 1/2 open. Then you can adjust from there. We have some that are afraid to light the torch and will only turn on the acetylene then light it. It works, but then you have soot flying all over the place. The settings on the tanks have been around 15lbs. on each. I've never had a problem lighting one on the first try.

 

[joel.palembang]

Greeting from Indonesia,

Hi iam newbie

Thanks for your good info,
Actually i use victor performer with 4-MFA-1 Rosebud Heating Tip, 2 times i think i get sustained backfire, lil scare to start again.

and i use this 4-MFA-1 Rosebud Heating Tip, to much happen "pop sound" when i use it.

Sorry for my bad english...

Joel

 

[Kevin54]

Joel.....Welcome to Garage Journal

Make sure the settings on your tank gauges are turned up high enough to use the Rosebud. I usually run the acetylene at 10lbs and the Oxygen about the same at 10lbs. On the torch head open either just the acetylene and light it, then add your oxygen (you'll get a lot of black soot at first), or open them both the same amount and light it. It may pop but won't burn back into the head.

IF IT POPS, then goes out, and you hear it whistle, turn the knobs on the torch head for both the oxygen and acetylene off as it is now burning in the head. When it does that make sure the rosebud valve are shut down, let the tip cool, Then light it again.

A rosebud takes a lot of oxygen and acetylene, so when it pops, or pops and whistles when burning in the head you initially didn't have enough duel to run it.

Here is a good article http://www.weldingtipsandtricks.com/cutting-torch-5.html

BTW Joel....your English is just fine. It's mine you may have to worry about.

And again, Welcome, and I hope we'll hear more from you.

 

[joel.palembang]

Thanks very much kevin to share your experience....
I just know from this forum and you, this "must" supply with a lot of oxygen and ace...

I use many simple torch (cheap) with butane or propane for brazing or heating, this victor heater is really2 good for me...
Even i use safe equiptment with Victor FC torch, i'm still nervouse to hear "whistle" of sustained backfire hehehe...maybe iam too much to see learning and warning video about Oxy-Ace on youtube ...

@now iam still waiting a package of Victor TurboTorch TX-500 Pro Pack (buy from ebay), i hope this powerfull enough with propane.

and last night i use victor welding tip no.0 to brazing Aluminum Heatsink, this more convenience, the distance of brazing fire from Tip to aluminum heatsink around 4-7 inch, and i put thermoucouple to monitor and keep temperature around 752 F maximum, success but need more time..., no pop , no sustained backfire....

I just realized...why is almost no pop and no backfire on small tip in my experience, because small tip consume more lil oxy ace than rosebud heater, and my habbit always be afraid to open more pressure on Oxy and Ace, i always open acetylene output 5-7 psi from regulator, oxy 10psi, and i use flashback arrestor on both regulator, and victor fc100 torch have flashback, and it will make all gas stream more weak when reach the torch...

Thanks again for your enlightenment


Regards

Joel

 

[Professur]

Threads like this are the reason I don't own an A/O torch.