Millermatic 135 the Nuts and Bolts

By Bill Byers / October 13, 2019
Millermatic 135

Popular, flexible no wonder Millermatic 135s are still sought after and used. No longer sold but if you keep an eye out, you may find one lightly used on the second user market place.

And if you find one, it is well worth picking one up - assuming you can get a sweet price on it.

Flexible, in that you can use flux core welding wire or solid wire with shielding gas. For its day and even now you can still do a lot of home welding jobs and start your journey learning MIG welding with one of these babies.

I've conducted in-depth research so I can take you on a tour of the Miller 135 MIG welder. I show you the nuts and bolts and go into the Miller 135 specs.

The Millermatic 135 115v wire welder may be an oldie but it is goodie.

Quick Overview Chart of the Millermatic 135 115v Wire Welder Specifications

Features
​Millermatic 135

Duty Cycle

20% at 90 Amp

Welding Range

30 to 135 Amp

Power Input

Normal Household, 20 Amp
fused circuit with a good Earth connection

Welding Wires

Flux Core or Mild Steel Solid Wire or Stainless Steel

Thermal Overload Protection

Yes

​Max Weld Width

24 Gauge to 3/16 ths inch

Metals Welded

​Mild Steel, Stainless Steel, Aluminum with Controller Adaptor and Spoolmate Spool Gun

Weight

60 lbs.

​Size

​17.5 L x 10.5/8 W x 15.3/4 H inches


Buying a Second User Millermatic 135 Wire Welder

​So you've checked around, been watching Craigslist like crazy and you think you've found one. What now? Ok let me suggest a few points. You want to make sure you've done your homework and know when you see a good price.

If you can get a working regulator and a gas cylinder thrown in as part of the deal then great.

That means you won't have to buy those separately.

Go along and see it working.

If you are not confident yourself using it then ask the seller to show you the Millermatic 135 welder doing a few welds of the type you want to do - always bearing in mind the capability of the machine.

Bring along some example scrap metals yourself and see it working at various outputs and wire feed speeds.

Does it work ok?

It does? Well then go ahead and negotiate on a price.

Oh, and don't forget, have a think about how you are going to get it and its cylinder, if it comes with one, safely home.

The Millermatic 135 MIG Welder - What was originally included?

The Millermatic 135 welder originally came with;

  • Miller M10 MIG gun including hose to the gun
  • Ground clamp and cable
  • Gas regulator and gas hose
  • Dual groove drive roll

You might want to take a look at what originally came with the welder and check it off against your second user unit Miller 135 unit. And check if anything needs replacing.

YouTube Video: Millermatic MIG Welders: What's Included

​Here is a YouTube video that goes over the originally included parts.

Video Credit: Miller Electric

How do I find replacement parts and Accessories?

Amazon is quite a good source of replacement parts and consumables. I've taken some time and done some research on your behalf to make your search a bit quicker.

I've only included Miller Electric manufactured parts, though there is a whole raft of compatible suppliers of replacement MIG guns, liners and the like available to try.

It is also worth checking direct on the Miller Electric site.

(**Buttons are Paid Commission Links)

​Product

​On Amazon

Genuine Miller Part for Millermatic. Size .023 Contact Tips. 10 in packet

Genuine Miller Part for Millermatic. Size .030 Contact Tips. 10 in packet

Genuine Miller Part for Millermatic. Size .035 Contact Tips. 10 in packet

​Protective Cover for Millermatic 140, 180, Cover is compatible with and for Millermatic 135

​(**Buttons are Paid Commission Links)

​Welding Wires

​On WelditMyself

​Mild Steel Welding wire

Flux Core Wire for Mild Steel

Flux Core Wire for Stainless Steel

Millermatic 135 Specs

Known for its easy set up and use, the Millermatic 135 specs were great for its day and are pretty good even now.

On the front at the top is the Wire Speed dial that ranges from 10 to 100.

Millermatic 135 Front Dials

Millermatic 135 Front Dials

Below that is the voltage control dial. This dial ranges from 1 to 10.

Below that are three areas. The first is where you plug in your gun, next is the Over Temperature light and last is the on/off power switch.

Inside is a fan that runs to cool the internals of the MIG welder.

Able to weld from 3/16 ths through to 24 gauge. The Miller 135 wire feed welder uses flux core or solid wire with shielding gas should you wish.

And you can plug it into and run it on normal 120V household power.

Setting Voltage on the 135 Millermatic Welder

​The voltage settings dial runs from 1 to 10 and the Millermatic 135 wire welder has an output welding voltage range from 30 Amp to 135 Amp.

The welding guide chart or weld parameter chart as Miller Electric calls it is on the inside of Millermatic and details the width/gauge of metal and the suggested setting for the dial.

If you find your second user Miller 135 MIG welder has a damaged welding guide chart. Don't worry the chart is also reproduced in the Owners Manual so you can take a look at it in there.

The chart is reall a guide and you will need to play around a little to find the right setting for your conditions and what you are welding.

What is the Duty Cycle of the Millermatic 135?

This is one of the most important things to understand about your welder to prevent damage to it. The Millermatic 135 specs show it is a great home use welder designed for light to medium duty cycles with its duty cycle of 90 Amp at 20%.

Which isn't bad but it's no heavy duty welder.

Though you may be surprised at what you can do with this.

This duty cycle means that over a ten minute theoretical welding period you can weld for 2 minutes at the 90 Amp setting before you over heat the Millermatic. Stop short of 2 minutes and you can rest the welder for 8 minutes to cool down.

Go over the 2 minute mark and you have a 15 minute wait before you can weld again.

Millermatic 135 Welder Thermal Cut Out

​This Millermatic has inbuilt thermal cut out which will kick in should you exceed the duty cycle and overhead the welder or the airflow to the unit be obstructed. Be sure to keep 18 inches clear back and front to allow the fan to draw in the air it needs to cool your welder.

Should the Over Temperature light come on at the front of the unit the ability to weld will be stopped. Leave the Millermatic plugged in so that the fan will continue to run, cooling the welder.

You will have to wait 15 minutes for the unit to cool before you can continue welding. Press the reset button on the back to reset the thermal cut out.

YouTube Video: Thermal Overload Protection

​This quick 12 second video describes the feature.

Miller Welder Feature - Thermal Overload Protection

Video Credit: Miller Electric

What Welding Wires does this Miller 135 MIG Welder use?

​For its time it really was a flexible welder, and that is why the Miller 135 specs make it is so popular today with many searching for a good second hand unit.

The Miller 135 wire feed welder uses solid wire, stainless steel wire and can use flux core welding wire.

Welding Wire
​Size

Solid Wire for Mild Steel

0.023 to 0.030

Stainless Steel Wire

0.023 to 0.030

​Flux Core Wire

​0.030 to 0.035

​The Miller 135 welder comes equipped with a dual grooved drive roll to accommodate the different sizes of wire the welder can feed.

Miller 135 Wire, drive roll and contact tips

Miller 135 Wire, drive roll and contact tips

The drive roll has two grooves. The drive roll will accommodate 0.030 and 0.035 inch wire in one groove and 0.023 in the other.

Just be sure you turn the drive roll round so that it's set up to feed the welding wire through the right groove in the drive roll for the wire you are using.

Millermatic 135 4 inch and 8 Inch Spools

Millermatic 135 4 inch and 8 Inch Spools

The Miller 135 MIG welder can use four inch (two pound) reels and eight inch (ten pound) reels. The Miller 135 MIG welder specs show the welder was originally supplied with an adaptor so you could use the larger (ten pound) reels of wire.

The welding guide chart details the wire feed speed suggested for the width of the metal you are welding along with the wire type and size you are using to help you along.

Millermatic 135 Wire Speed Dial

Millermatic 135 Wire Speed Dial

​The wire speed dial is variable and can feed wire out at between 20 and 600 inches per minute, which is pretty good for this type of welder.

Millermatic 135 Gas Regulator

Millermatic 135 Gas Regulator

Using Shielding Gasses on the Millermatic 135?

​Yes, you can use a normal 75%/25% Argon Carbon Dioxide mix or 100% CO2 or Tri-Mix. The welding chart again is your guide here showing suggested wire/gas mix for the width of metal you are looking to weld together.

Type of Metals the Millermatic 135 Welder is capable of Welding?

​You can weld mild steel with solid wire and shielding gas or you can use flux core welding wire. You can weld mild steel from 1/8th to 24 gauge. Or

Stainless steel with solid stainless steel wire and Tri-mix gas from 1/8th of an inch to 24 gauge.

Mild steel with flux core (recommended for deeper penetration) for 3/16 ths of an inch to 16 gauge.

Be sure to change the polarity to GMAW (cable to the gun connected to the positive output terminal) if you are using solid wire with shielding gas.

or

FCAW (cable to the gun connected to the negative output terminal) if you are using flux core wire.To set yourself up properly for welding.

​Aluminum Welding? Millermatic 135 Spool Gun?

​The Millermatic 135 MIG welder is not capable of Aluminum welding using a spool gun without the SGA-100 controller/adaptor to go with it.  - see the FAQ's below for a full explanation.

Is the Millermatic 135 MIG welder a 115 Volt Wire Welder?

​Yes, it is often referred to as a Millermatic 135 115v wire welder.

The Millermatic 135 specs call for a normal household 120v circuit, power and normal 3 pin plug. You'll need a 20 Amp minimum fused circuit with a good earth to plug it into.

It should be the only electrical thing drawing power on that circuit, otherwise you won't get the full welding output voltage.

And you should consider using a 30 Amp fused circuit to get the max output from your Millermatic.

Dimensions of the Millermatic 135 Wire Welder and is it Portable?

With dimensions of:

Length 17.5 inches, Width 10 and 5/8 inches, Height 15 3/4 inches.

Weight is 60 lbs.

Quite heavy to lift, but yes portable.

I'd suggest getting a cart. Or even better building yourself one as a starter project with your Miller 135 MIG welder.

The Millermatic 135 Manual

​Compared to some of the more modern welders the Owners Manual provided by Miller Electric is good. Explains the welder well, its set up and how to use it. I've provided a link to a copy of it here.

Millermatic 135 Manual

PDF Document Credit: Miller Electric

Millermatic 135 Parts List and Wiring Diagram

​If your Miller 135 MIG welder needs a bit of TLC to get it working great for you again you may want to take a peak at the wiring diagram.

It is in the owners manual (link just above).

You'll find the wiring diagram on pages 29 to 30.

Here is a separate link to the parts listing in case you don't want to download the whole owners manual.

Millermatic 135 Parts List

PDF Document Credit: Miller Electric

What year was my Miller 135 MIG Welder Made?

​If you found your second user Miller matic 135 on-line or on Craigslist then you may want to check how old it is.

It's easy to find out. You'll need the serial number. Then you can look up the year of manufacture in the Serial Number Year Chart and your question will be answered.

Here is a link to it

Serial Number Year Chart

Replacing the Millermatic 135 MIG Welder

​At some point you may want to check out what is around on the market that would be a good replacement for your Miller 135 wire feed welder.

You could check out the Hobart Handler 140. I've spent some time researching and reviewing the Hobart Handler 140 and have a write up on it. You can read it at this link.

Hobart Handler 140 Review

If you go for a Hobart 140 replacement you will be keeping to the same manufacturing family and the Hobart Handler is a really good welder.

Fancy a change?

You could take a look at the Lincoln Electric 140 as the two - the Hobart 140 and the Lincoln Electric 140 often go head to head.

How to use the Millermatic 135?

​Taking a look at this 5 minute video from Miller Electric will help get you started.

YouTube Video: Miller Millermatic MIG Welder Set up

​Millermatic MIG Welder Set up

Video Credit: Miller Electric

No time for the video? Here is an overview.

Set up choosing your wire of choice - flux core or solid wire with appropriate shielding gas. Connect up your ground clamp to your work piece. 

​Be sure the piece you are welding is clean where you connect up your ground clamp. This is so that you get the best electrical connection.

​And clean off any oil, rust, paint or other surface contaminants.

Then it's simply a matter of checking the welding chart guide for your starting positions for wire speed and output voltage. Bring the torch to your work piece and press the trigger.

Be sure to have yourself protected with a good welding helmet, gloves and apron.

Clear the area of anything a spark might set alight to.

Frequently Asked Questions

A. Can the Millermatic 135 Use a Spool Gun to Weld Aluminum?

The Millermatic 135 welder had an optional accessory the Spoolmate 3035. It needed a controller/adaptor, the SGA-100 for the Millermatic 135 to use it. The controller needs its own separate 115v power supply.

With this combination you can weld 14 gauge - 1/8th inch Aluminum.

I've provided a link so that you can take a look at the Spoolmate 3035 Spool Gun's specification sheet.

Spoolmate 3035 Spool Gun

The Spoolmate 3035 plus adaptor combination is a pretty pricy combination and may set you back the same amount of dollars as your second user Millermatic 135.

Without the Spoolmate 3035 and the SGA-100 the option is to weld without.

There are YouTube videos showing you how you can go about changing the internal electrics to accommodate a spool gun on the 135 and you may well want to go that way.

However the Millermatic 135 has limited power output and any Aluminum welding that is serious will be past its capability.

Some have put in a Teflon liner, used 100% Argon and fed Aluminum up the hose to the MIG gun from the wire spool, so possible, if tricky, as Aluminum is difficult to feed reliably up a MIG hose.

However you will be very limited to the thickness of Aluminum you could weld and you will lack welding power.

If you want to weld Aluminum and you don't want to go the spool gun plus adaptor route, it would be better to choose a MIG better suited to it.

Like the Lincoln 140 or the Everlast 140.

B. Is the Millermatic 135 MIG Welder Any Good?

Yes, definitely otherwise not only would they still not be around but people wouldn't be keeping an eye out for when one comes up for sale. They are ideal for small jobs around the home and workshop and for where you don't have access to 220V power for a larger machine.

C. Can you replace the Contact Tips?

​Yes, easy, they are standard parts,

just screw them off and put on 0.023 or 0.030 or 0.035 replacements.

D. Can I use an Extension Cord?

Yes, 14 AWG for up to 50 feet and 12 AWG for 50 feet to 200 feet.

You may want to go to more heavy duty cable to get the maximum power output from your welder.

Be sure to choose an extension cord cable that is suitable for working outside if the conditions you are working in warrant it as those cables have heavier insulation to protect the cable.

E. Millermatic 135 not feeding, things to check for

​There are some easy checks you can make to ensure that it's not something obvious that could be causing you problems.

  • Check if the pressure adjustment knob on your wire too tight or too light? Try easing it off or on to see if that helps.
  • Is your welding wire feeding cleanly? Not rusty or curled over itself on the spool. Replace rusting wire or un-reel it to clean wire and cut off all the rusty parts. You may need a new spool of wire.
  • What about the wire spool hub? Is the nut too tight? There should only be a slight tension when you turn the spool.
  • Is the liner to the MIG gun clean and free of debris? Is it kinked somewhere? You can use gas to blow air through the liner to clear it of debris. A damaged or kinked liner will cause you a lot of problems. The liner may need replacing.

YouTube Video on Replacing The Millermatic 135 MIG Welder Gun Liner

​Wondering how? This 3 and a half minute YouTube video will point you in the right direction.

Replacing You MIG gun Liner

Video Credit: Miller Electric

Circuit Board Issues?

If you want to investigate the circuit board issues other people have experienced, then this discussion thread may be useful.

Discussion Link Credit: Hobart Welders.

F. Care of your Miller 135 MIG Welder

It's recommended that every six months you vacuum out the inside of the welder to clear any dust or debris so you get optimum airflow. Probably the first thing you should do on getting a second user unit.

Every 3 months you should check for cracked cables, check the terminal nuts to make sure you are getting good polarity connections.

Get new contact tips if the old ones are worn or there is debris you are unable to clean off.

Check and replace the gun liner if kinked.

Who Made the 135 Millermatic MIG Welder?

​The Millermatic brand of welders is designed by Miller Electric Mfg who are based in Appleton in Wisconsin. Miller Electric started in 1929 they are one of the largest welding manufacturers and are US based.

The Millermatic brand was first brought onto the market during the 1970's and the aim of the brand was to bring arc welding into the reach of the everyday person who wanted to weld.

I think they achieved their aim.

In 1996 ITW (Illinois Tool Works) bought Miller Electric and it is now a wholly owned subsidiary of that company. ITW also owns Hobart, another big name in MIG designing and manufacturing in the USA. A number of the Hobart components can be used interchangeably in the Miller Electric welders.

Last Words

So there you have it, the guide, the complete nuts and bolts. The Millermatic 135 MIG welder is a great welder if you are in the market for a light to mid duty welder. If you can find one out there in good condition and for the right price, it'll be well worth picking it up, beginner or pro alike.