welding boat trailer

[troy]

At the moment i have a small compact 2 cigweld 100 amps takes 2.5 and 3.25 rods.
i am building a trailer for pulling boat out of the water when i go to the cape.
making it out of 4x2 box section with 4 ml wall thickness.
getting varying advice some say the welder want do the job others say it will.
can anyone give the correct advise as i do not want to buy another welder if i can get out of it.
they say the wall thickness is the problem yet i have made tractor carriers to pull the boat out with it .admittedly only 2x2 box and not 4 ml .
many thanks if you can help .
troy

[logan_whiting]

i just did a welding at tafe this week, it will do the job fine !!!!!

[dugong]

if i understand you, its just a storage trailer, not a real boat trailer for highway use???
i'll ask a qualified welder i know and see what he says.
cheers

[Richard]

I just redid parts of my road trailer which was up to 3mm stuff with the same welder and it worked fine. Just take your time to make sure you heat up the metal is all..


richard

[revs57]

Troy, It should do it O.K., you've just gotta get enough heat into the 4mm to have good penetration. If you're concerned with penetration (ie 4mm wall thinkness) scarf the joints back with an angle grinder, lay the first run in with a deep penetrating low hydrogen rod, scarf it back and cap it up with your normal gp rod. If you do verticle, go up, not down. 120 amps up your sleeve would be nice, but with good preparation you should be able to get away with it.

Have you done much welding mate?

Rhys

[blaze]

I think the 100 x 50 x "4mm" is over kill for the frame. To get the strongest weld you need full penatration. I think the only chance you will have is with the smaller rods (I also have the feeling that your welder has not adjustable amps) using the 3.25 setting on the welder for the highest amps. Your welder will not run low hydrogen rods.
cheers
blaze

[clutter]

Use something like a CIG Satincraft 2.5mm rod, they are a general purpose and easy to use. To make sure you get good penetration just slow down the run a bit and watch the "pool". Dont worry about verticle up or down welding, you should be able to roll the trailer around so that all your welds are down hand. Like Blaze said, that welder won't run low hydrogen rods and you wouldn't need them anyway as its not a structural job in the technical sence. Like anything, preparation is the key so take your time to set it all up and prep it correctly. Make sure you tack it securley before welding it out completely.

Best of luck,
Clutter

[troy]

I think the 100 x 50 x "4mm" is over kill for the frame. To get the strongest weld you need full penatration. I think the only chance you will have is with the smaller rods (I also have the feeling that your welder has not adjustable amps) using the 3.25 setting on the welder for the highest amps. Your welder will not run low hydrogen rods.
cheers
blaze
Blase i fully agree with you on the over kill business with the size but a few on the site recommened it .anyway not to worry i have paid for it .
thanks mate good to hear from a Tasmanian apparently you have your chop and i seem to have the nq one.
troy :D :D :D :D

[FNQCairns]

I dont know how handy you are with a stick but here is my experience.

I did mine 3.5mm, with what I think is the exact same welder and the 2.5 rods. I found I had to turn it up into the 3.25 rod settings - virtually flat out to get enough heat/penetration. I couldn't get it to push the 3.25 rods possibly because of my experience level.

Overall the biggest problem was the duty cycle on the thing, when you want to get stuck into it, plan on spending 7-10 times longer waiting for it to cool down and turn back on than actually welding - no exaggeration either. Unless the welder is dead cold it will not make a complete trip around a 2 by 4 section without cutting out for 20min, then it will be flat out getting 1/3 the way around before another 20min wait.

All of my welds got double welds and some extra important ones got 3 passes, I found out by welding and then cutting the weld on test pieces before starting the trailer that as a result of my poor ability with a welder and/or the low power and thin rods that my first pass was never quite good enough in penetration but the second was.

So imo that welder with the duty cycle and 4mm steel and 2.5 rods?I would for blood pressure reasons consider upgrading a step or so or at least keep the option open.
fnq

[blaze]

A trick to get a little more duty cycle out of a small welder is to sit the welder on a drum and get a big air fan and poke up its bum to help cool it down.
cheers
blaze

[familyman]

Or pinch the fan out of a microwave on kerbside collection or junkyard and stick that in .PRESTO 80-90%duty cycle ;)
If you really want penetration get 2.0 mm rods and run them on the 3.5 mm setting.You will go through the rods though.Also make sure your earth clamp is making good ie flat to flat contact with the job ,a poor contact here will make you and your machine work a lot harder to get a good weld.Good luck
cheers jon

[Owen]

A trick to get a little more duty cycle out of a small welder is to sit the welder on a drum and get a big air fan and poke up its bum to help cool it down.
cheers
blaze

Be very careful doing this as all you are doing for the most part is cooling the thermal overload sensor, not the componentry that is actually going to fry.

Troy,
I sell welding equipment for a living and to be honest you have a pretty light on machine for what you want to do.
If you a reasonably proficient with a stick welder then it will get you by, but stick to 2.0 or 2.5mm electrodes and prepare your joints.
Practice on some offcuts and break the joints open or look inside until you are getting full penetration. I realise that this trailer won't be used on the highway, but you may as well do it right.
Don't skimp on the electrodes. i.e buy well known brands like WIA or Cigweld as there are plenty of crap chinese electrodes out there.
What I would really suggest you think about is hiring a single phase MIG welder of about 250 amps capacity and use that instead. They are easier for the novice to handle and will give plenty of penetration on that size material.
I wouldn't recommend gasless wire if you can do the job inside.
Just remember with a MIG (using solid wire & gas) that you "push" the weld, not drag it like a stick.
cheers,
Owen

[troy]

Revs 57 i have done a fair bit of welding but that does not mean by any stretch of the imagination that i would even hold a candle to a tradesmens you know what.
troy

[troy]

Here is where i see myself at this stage i think i might have to buy another welder.
do i buy auni mig 120 panther for 579.00
a 150 amp stick welder 470.00
or cheap uni arc 25% at 140 amps [not sure what that actually means]295.00
trouble with the mig is i have never used one before.
thanks.
troy

[blaze]

migs are easier to use than stick, See if you can track down a cig brumby, 200 amps I think, gas or gasless, small or large spools of wire and will run stailess and aliminum wire. cant kill em
cheers
blaze

[familyman]

Troy shop around and see if you can get an inverter single phase by lincoln or cigweld or esab .They are feather weight and will run 2.5mm rods all day.Also because they are DC they produce a strong stable and Helen Keller could weld with one.Only one catch - you wont get one for under $950 thats worth owning.But you can convert them to tig for ally and staino with a suitable gas control setup. ::)
cheers jon

[blaze]

the little invertors will not tig ali only stainless $4000 or there abouts will do both

[clutter]

Nothing wrong with the UNIMIG 120 but if you can find a mig in the 150 to 170amp range would be better. Not sure where you are but Glenfords would have something and it looks like you already know about Tradetools even the major hardware chains will carry them. Keep an eye out for a used one in the weekend papers also. I used a unimig for many years and will probably buy a 195 again soon. The mig gives you alot more options and allows you to sucessfully weld materials from thin gauge to reasonably thick. Just one tip though, if you buy one don't tell your mates because you'll be forever doing "little" jobs for them.

Cheers, Clutter

[dugong]

spoke to the welder, he said you should be able to do it with 2.5mm rods and set the welder for around 80amps and see how it goes. the duty cycle may be fairly low and the welder may stop a lot due to over heating.

welder recommended wia 12p rods, no cheapies.

welder recommended tacking the trailer out first with your welder and then hiring a larger welder and using 3.2mm rods at around 120amps.

if you do decide to buy a bigger welder just be aware to compare the duty cycles and weather it has a inbuilt fan or not
cheers

[troy]

Hi Owen with the mig you said you have to ''push '' the weld and not drag it.
why is this as i do not know how i would go doing that.
thanks
troy

[ANYFISH]

You get better penitration when you push the mig.
also a small(1mm)penno gap will help with the strength.

anyfish

[Owen]

Hi Owen with the mig you said you have to ''push '' the weld and not drag it.
why is this as i do not know how i would go doing that.
thanks
troy

Troy,
With a MIG (when using gas) you have to push the weld to keep the gas over the weld pool.
If you are using gasless wire you pull just the same as a stick. The flux in the gasless wire creates the gas required to keep the air out of the weld pool.
As to the Unimig 120, it is still undersized for what you want to do.
The duty cylcle is the length of time in a ten minute cycle you can run the machine at the specified amperage. So if it is 120 amps @ 35% then you can run it for 3.5 minutes @ 120 amps. After that it will heat up to the point where you lose power and it will usually shut down.
The duty cycle tells you the real working capacity of the machine. The peak power is not necessarily the best thing to look at. There are 230 amp machines from the likes of SIP & Unimig that have less real working capacity than 195 amp machines from other brands due to their low duty cycle.
I would recommend a machine of at least 150 amps capacity and strongly suggest you look at WIA, Lincoln or Cigweld in that order. They are also priced in that order, but you get what you pay for. The big difference between the cheaper units and the ones I have mentioned is the quality of the torch and drive roller systems.
If you have a cheap torch you will have a lot more feed problems. i.e. The wire will jam up in the liner more. You will get more burnbacks into the tip etc. If you have a poor drive roller/feed system you will find it harder to get reliable feding of the wire which will in turn cause more burnbacks.
In the end, buy the best you can afford and talk only to sales staff that are actually tradesmen.
Don't believe the bullshit that one of those $500 MIGS is going to reliably weld aluminium etc, they won't. There is a huge difference between just burning the wire and producing quality welds.
Also don't believe it is dead easy with a MIG. If it was, you wouldn't have apprenticeships to learn it. Easier - Yes. Easy - No.
You are welcome to ring me on 07 4978 4888 during business hours if you want to ask questions.

cheers,

Owen

[troy]

Owen what would you advise me to buy to do the job.
maybe i might be able to deal with you even though freight costs might come into it.
apart from that i really appreciate your help and everyone elses.
troy

[Owen]

Troy,
Unless you live in Gladstone, then go see your local guys. Welders are heavy and the freight will kill you. Also it is better to have the support and service of the guys you bought it off. Have a look around your area and PM me the prices you're quoted. I'll tell you if they are fair.
As to what to buy, then you need to consider how often and what you want to use it for.
If you are never going to need to weld things less than say 3mm thick steel, then a stick welder will probably be all you need.
If you only do the occasional bit of panel work on the car, then a cheap MIG will get you by.
But if you want to be able to weld a wide range of applications, then spend the money to get a decent machine.
The list of preference I gave above is just that - my preference - and applies only when talking sub 200 amp machines. Give me five different scenarios and I'll probably recommend five different machines.
Also be aware that even with a good machine, there are places on your tinnie where a MIG is not suitable for repair work. Around the chines, keel section or anywhere there is a good solid extrusion, then MIG is fine. Anywhere there is only thin plate (as in cracks in the floor etc) you really should use a TIG.
As I said earlier, if this trailer is all you want to do, then tack it together with what you have now and just go hire a 230 - 250 amp single phase MIG for a day for the welding.
cheers,
Owen

[troy]

As stated at the beginning i only have a compact 2 cig welder 100 amps.
I went into Bunnings yesterday and i was told if i went any larger in either the mig or stick i would have to alter my switchboard and dig up the underground wiring leading to the shed and replace with heavier wire otherwise i would either keep tripping the fuse or set my house on fire.
Ido not have 3 phase but i did not think i would need to change anything by say going up an extra 95 amps.
any suggestions on what next step to take .
thanks
troy

[Owen]

And the qualifications of that particular "sales person" were?
Troy, don't go to a toy shop to talk about tools ;)
Firstly, I can't say with 100% certainty that using a larger welder will not blow a fuse or trip a breaker on your particular home/shed.
Larger machines in general draw more current. What size outlet are you going to run it off?
If you only have 10 amp outlets in your shed then your are theoretically limited to a machine aproved for sale with a 10 amp plug fitted.
If you have 15 amp outlets then there is no problem using a machine fitted with a 15 amp plug. That is not to say that you won't blow a fuse or breaker. Many single phase welders can draw anything up to 40 amps. On a modern home this is rarely a problem. You'll blow the fuse or breaker long before you damage any wiring. That's what they are there for. That does not mean you should push the envelope too hard by going too big.
If you're really worried, get a sparky to check your shed out and tell him the maximum current draw of the machine(s) in question. (It's written on the back of the machine if the experts at Bunnings can't find it).
In my experience however you will have no problem running a MIG of up to about 230 amps in almost any relatively modern home/shed. Transformer style stick welders up to about 130-150 amps are generally OK too. And inverter style machines up to 180-200 amps are usually fine too.
But as I said at the beggining, I don't know when, how or by whom your wiring was done.

cheers,
Owen

[troy]

Power pionts in the shed are 10 amps -the underground cable running from the house to the shed has nothing else running off it - the fuse is 15 amps.
sounds like i am in trouble as the the larger welders have a 15 amp plug.
The only electrician i could talk to said he could make me up a adaptor with a 15 amp at one end and a 10 amp on the other.
any advise.
thanhs troy

[Mantaray]

The only electrician i could talk to said he could make me up a adaptor with a 15 amp at one end and a 10 amp on the other.
any advise.

Go find a proper electrician!

[jimbo59]

gday troy,if u can borrow a oxy welder to pre-heat the work your little stik will do the job.Iown a cig 150 mig they are ok,i just ground the earth terminal on the plug to do welding at customers houses when doing general welding,no problems for over 15 years now,somone will probebly say its terrible dangeous but it works for me.

[Eagle]

Hi Troy,
I have a "Weldmate 160" welder, it is made in the EEC. I bought mine from Glenfords here in Rockhampton. It will burn 3.25mm rods at a rate of 25 rods per hour or 1 rod every 2.4 minutes. It will do this all day. I run mine from a 10 amp supply out in my garage. The only negative aspect with this welder are the leads. It will perform even better if you swap the flimsy leads for decent heavy duty ones and also change the handset and the earth clamp. I have done only a minimal amount of welding using a MIG set (and that was when teaching welding as an instructor) and found it hard going. It was all to easy to get a beautiful looking weld and not have ANY bonding to the parent metal. I also found the extra glare from the unshielded arc made seeing the weld zone very difficult. A much darker lens was needed and then I was unable to see what I was doing.
It is much easier to stick weld and as Owen stated, preparation is the secret to a good weld. With 4mm RHS, the metal needs to be beveled to produce a thickness at the edge of about 1mm to no more than 1.5mm. Space the parts about 1mm and run the weld. Definitely use a recognised brand of rod. My favorite are Satincraft 13 made by CIG. These burn with a very stable arc and are easy to use. Don't buy the cheap Chinese rods. The fumes from these are real bad news and I dont like the weld deposit. I dont trust the quality of the deposited metal or the flux for that matter either. I wouldn't use an oxy torch for preheating, it is far to expensive to burn. A far better preheat would be to use LPG. Definitely preheat the steel before welding it even if only tacking it up. I prefer to use rods as there are no problems with jambed feed rollers, burn backs, rusty wire or finding the right spool when you run out. To each his own but ask yourself what would you do with a higher priced specialised welder after you build the rig you have planned.
Good luck on your project
Joe / Eagle

[troy]

Hi Eagle i just got a quote from Glenfords in Townsville and on a 140 amp weldmate they quoted me 240.00 sounds a bit cheap.
troy.

[Mantaray]

This project is starting to have cracks appear already! Wouldn't it be less expensive in the long run to have it done professionally?

[troy]

Mantaray what do you mean and do you really know the cost if it was done professionaly.
i am capable of building this trailer myself and i am not afraid to ask advise.
Is only a beach trailer why should i pay a professional to build it.
The beauty of this site is you can get advise and you can take it or leave it.
If you see cracks appearing then that is your right but in the meantime i value the opinions i have been getting.
Apart from the cracks you are seeing beside getting in professional advise what would you do.

troy

[troy]

Eagle this has become a very interesting issue as far as i am concerned and i #am definately not having a go at you or anyone else.
Weldmate 150 amps [glenfords in Rockhamton said it will not do the job ]Glenfords in Mackay said it will do the work easily ]
Who are we suppose to believe .
I am not worried about the cost but the fact that people can easily get caught by salespeople who do not know there jobs.
troy

[blaze]

troy
if those cracks appear you can always grind them out and reweld them LOL
I think you are talking about a 140 amp mig?
As I said somewhere before I have a CIG Brumby 180 amps, I have welded 1/2 plate with it, but is more suited to 6mm plate, the extra 40 amps would make a fair bit of difference IMO.
If you are talking migs the wire feed rollers are faily critical, wire feed motor etc
cheers
blaze

[troy]

Blase they are talking about stick welders.
thanks
troy

[revs57]

Ahhh Troy, I might step back into it...stick to your guns mate, I had a 140 amp peerless home welder years ago (definitely not 3 phase) and what I couldn't do with that wasn't worth doing. I have a trade background in fitting, but have worked in welding...its all in the preparation....and stick welders are fine with good prep....just a little slower is all...I like Owens comments which is why I bowed out of the discussion...but IMO a 140 amp welder is plenty for most of the stuff you are talking about...Rhys

[blaze]

140 amp stick will do the job Troy, every man and his dog used to have one in the shed, see if you can get a dc inverter as opposed to ac welder. A solid wound 14o amp ac welder would be the best in the ac range. (easy way to tell is they break your back when ya pick em up) If your choice has a fan, that is good
cheers
blaze

[bluewaterbandit]

good advice blades when they heat up they cut out on their overload cheers blue

[troy]

Blase a salesman at Glenfords told me the duty cycle on the 140 amp Welmate is 23% at 80 amps and 6% at 240 amps.
I was looking at the 150 but thought i would get some more advise from you guys after this latest information.
troy

[Owen]

http://www.welding.com.au/pages/understanding_duty_cycle.htm

[blaze]

Only My opinion
The duty cycle is very important BUT when doing something like fabricating a trailer you will most likely find you dont reach max duty cycle often because you dont normal just weld.
tack, check, put a full run in that section (maybe a 125mm weld), tack, tack, cut more steel
get the picture
Only when completing the final welds you will find that change rods, checking this and tapping that, deslagging the welds
you may have to have the odd rest here but I dont think so
cheers
blaze

[bobp]

practise practise practise practise :) :)

but what would i know
welding from before i can remember on our cattle property
started my apprenticeship at 18 #so there is another 20yrs stuck with my head in a bucket
welding f***** bores the shit out of me .
the joys of being a boilermaker
just remember all good welders have spent 100's & 1000's of hours with there head stuck
in a welding sheild can weld in either hand and all positions.
it mite be fun at first but it soon wears thin when suck in a confined space getting the shit
brunt out of you >:( >:(
stick, tig ,mig(inershield), fusion ,brasing,soildering. #all take practise so just make sure #u have lots of off cuts and more rods now will save u lots of grinding later ;) ;)

bob
ps. i am curently working on 450 dia. steel pipe at the moment #and trust me after puting 3 runs into every joint #u look forward to the end of the day. we use mig and stick at diferant times
1 joint stick up to 4 hours
mig 1.5 to 2 hours all welds are done in position with root run ,hot pass, and cap
max working presure on pipe is 2500kpa #
aprox 180 joints just in the 450 dia with shit loads of smaller pipe aswell :P :P :P

[troy]

I ended up buying a 180 amp Flowarc and it was blowing the fuse all the time.
I called a electrician and he put a 15 amp piont on my metre box.
What i am worried about is i have to use a 20 metre extension cord and how many amps would i be losing.
thanks
troy

[blaze]

get a 20-25 amp extension cord with 15 amp ens put on (the lecy that did your power point should be able to help
I thought we may have been seeing some pics of the trailer
cheers
blaze

[troy]

Blase do you ever get the feeling you have just ran over a chinaman well that how my luck has been lately.
The trailer is starting to take shape and will post some pics when i learn how .
thanks
troy

[revs57]

good to see you're still at it Troy...looking forward to the pics

Rhys

[sporty1]

Hi Guys

must admit some very interesting discussions. I have a CIG Transmig 135 twin turbo welder. Is this suitable to weld floor supports into my tinnie? If so what gassless wire should I use?

[blaze]

sporty1
135 amps not enough IMO and you need to use argon gas to weld alloy
cheers
blaze
ps
troy
stick with it, if nothing else you will gain a wealth of experience and a trailer. I had one of those days better forgot yesterday

[clutter]

Troy,
Good to see it getting into shape, like I said before though, don't tell your mates you have one or else you'll be getting more practice than you need.

Cheers, Clutter

[troy]

What is the best way how to do vertical welding i am hopeless at it.
Maybe for the first time i need advise from Mantleray.
troy

[revs57]

Mate,

I always start from the bottom up...get a pool happening at the bottom, lift the rod up 12-15 mm, then return to the pool at the bottom and "stitch" it up, moving up and back to the pool at the bottom, up and back, up and back, laying each pool on top of the last as you work your way up...if you start from the top and weld down you usually get heaps of inclusions...

does this make sense???

cheers

rhys

[blaze]

when doing vertical welds the amps need to be slightly lower and you build a platform in a triangular fashion for corners and slowly build the platform up the corner, you need to keep a close eye on the molten pool to work out the speed you need to build the platform. Too slow and the pool will run down over the platform, too quick and you wont have a platform. Hold the rod at about 45 degrees from vertical as this helps stop the molton pool form drooping.
cheers
blaze

[clutter]

Troy,

I'd try to stay away from them if you haven't done them before, they're a pretty hard thing to learn without someone hanging over your shoulder giving some pointers. I'd be trying to roll the trailer on its side and just do a down hand.

Cheers, Clutter

[blaze]

hi clutter
not easy, but if ya dont have a go
cheers
blaze
ps
bloody over heads are worse when all the hot crap drops onto your head cause its to hot to wear a leather cap

[troy]

Well boys only ever had one go at overhead and that will do me just fine.
I thought i was under a volcano.
Troy