beginner question

[dylanb]

Hi

I want to learn to weld and plan on getting a mma welder to start with. I eventually want to make gym equipment and weight and have found that 11 gauge/3mm is most commonly used.

What I would like to know is when welding base or bolt plates and gussets how do I determine how thick they should be and should I get a welder strong enough for this or would 120-160 amp be enough?

sorry if this has answered i have searched the internet for a while and couldn't find an answer.
appreciate any help

 

[Dcal]

Hi dylanb, welcome to the forum

If using MMA on 3mm steel 120 to 160 will be plenty.
You will probably be using 2.5mm rods and they run 70 -100 amps depending on the flavour so that would give you a bit of head room.
If you need to weld thicker stuff you can prep the joint and use more runs.
MMA is a nice process and if done correctly will give nice, robust welds. It’s not the easiest process to get on to but well worth the effort.

DC inverters are cheap and work well but dont forget the PPE. If starting out I'd say an auto mask is a must.

 

[dylanb]

cheers for the reply, yeah I need to factor in the cost of decent ppe

 

[slim_boy_fat]

Welcome to the forum, dylanb Is this gym equipment going to be sold to others, or purely for yourself?

Be aware of the need for liability insurance if you're going to be selling what you produce - imagine the potential if your welds failed and a third party was seriously injured, or worse. Try a forum search, as this scenario has been discussed on here a number of times in the past.

Good luck and enjoy the 'metal melting'.

 

[tom2207]

if your selling the finished product , I would skip mma and look at tig , it gives a far better finished product look , for a lot less effort , less cleaning up too , time post weld clean up will become important , also very forgiving for gap filling on box sections too.
Just something to keep in mind.

 

[dylanb]

i dont plan on selling anything its just for a hobby and to try save money as gym equipment can be expensive, ill have a good look around the forums, cheers lads

 

[Dcal]

If you are trying to save money MMA will be by far the cheapest and functionally more than up to the job.
If done right there will be little clean up, a lot less than with mig anyway, but I agree with @tom2207 tig would be nicer.

 

[tom2207]

If you are trying to save money MMA will be by far the cheapest and functionally more than up to the job.
If done right there will be little clean up, a lot less than with mig anyway, but I agree with @tom2207 tig would be nicer.

i was half thinking buy a mma machine that has a tig option ,, and move to tig when it suits as its only steel a lift/scratch start will be fine and no need for bells and whistles ,,,,

 

[Barking Mat]

Second hand stuff always comes up cheap, after its been sat in the gym / garage for years.

But always good to learn to weld.

Welcome.

 

[Tinbasherdan]

Tig would be neater but unless experienced you stand a good chance of stuffing too much heat into it and twisting all the frame. 3mm steel, use a half decent 2.5mm rod at 70-75a

 

[bigegg]

A buzzbox/mma machine will do all you need to make gym equipment.
I used a 100a machine to weld car display ramps for several years - 3mm-6mm box, plate, and angle.
You'll find that you won't go above 120A - the extra capacity just gives you a longer welding time before allowing the machine to cool down.
That won't be an issue for gym equipment, as you'll spend much more time fitting up, and jumping from joint to joint.
There won't be any 100m runs like if you were welding up a boat!

To decide what sort of sizes for gussets, take a look at google images - or in a gym - at what is used on commercial stuff.
Be aware that welding 10mm plates (if neccessary) to the end of 3mm box section is an art which will take a fair amount of practice.

 

[dylanb]

A buzzbox/mma machine will do all you need to make gym equipment.
I used a 100a machine to weld car display ramps for several years - 3mm-6mm box, plate, and angle.
You'll find that you won't go above 120A - the extra capacity just gives you a longer welding time before allowing the machine to cool down.
That won't be an issue for gym equipment, as you'll spend much more time fitting up, and jumping from joint to joint.
There won't be any 100m runs like if you were welding up a boat!

To decide what sort of sizes for gussets, take a look at google images - or in a gym - at what is used on commercial stuff.
Be aware that welding 10mm plates (if neccessary) to the end of 3mm box section is an art which will take a fair amount of practice.

cheers , id say 6mm - 10mm plate will what ill be using but ill practice and test before I start to make anything substantial