Flex 3401 vs 4inch backing plate system carnage

**kosmetikwerks** · 12-03-2015, 04:37 PM

Originally Posted by roguegeek

That's too bad about those 4" backing plates. What's more unfortunate is you can only use the LC hybrid 5" pads on the LC 4" backing plate and not on the factory 4 3/8" backing plate. Guess I wont be using those 5" pads.

Maybe not! Here's an interesting mod done by a member of sister site autopia.Flex 3401 Modified Backing Plate

**7PaintGuns** · 12-03-2015, 04:53 PM

Okay so I literally just took my Flex out of the box... If you're running at speed 6 for an extended amount of time you should buy a rotary to compliment. I can see how a BP would fail with all that "agitation". But maybe that's just from my years of rotary use.

**Muddyoldgoat** · 12-03-2015, 05:30 PM

Speed preference aside, if the backing plate cannot handle the max speed of the machine it was made for then it should come with a advisory on it.
I've had 2 fail with felt ring oiled, and plates installed with the proper washers and bolts. 1 after a panel and a 1/2 on speed 6. The other after about a month of work going no more than speed 5.

**KMdef9** · 12-03-2015, 05:34 PM

If you over torqued it, I could see it causing this with the heat catalyst.

**7PaintGuns** · 12-03-2015, 06:12 PM

Originally Posted by Muddyoldgoat

Speed preference aside, if the backing plate cannot handle the max speed of the machine it was made for then it should come with a advisory on it.

Very good point...

**Mike@DedicatedPerfection** · 12-04-2015, 01:27 AM

Originally Posted by cardaddy

Me too... although my machine gets a LOT less use than yours does Mike.

Still can't figure the need for wide open on the 3401. Considering the pad never stops, EVER... and we should using the least aggressive approach... which can actually be 3.5 or 4, (especially with the smaller pads). Not saying you CAN'T run it faster from time to time. just that you really don't need to.

I'd rather just run it slow, move the arms slow, keep the pressure constant... and take the time to let the pad do the work.

That's what I really like about using the Menzerna range. FG400 runs at a slower speed while SF4000 runs at a faster rate. I never exceed speed 4 on the 3401 which allows the machine to run cooler and I can give it all the downward pressure I want without worrying about pad stall. I can sit on it for that matter and it will still maintain pad rotation.

And with SF4000 it likes a faster speed and I usually run speed 5 with it. In this step running at a faster clip doesn't faze the machine as with this step you are polishing the surface and all that downward pressure isn't needed. Get 'er set up to polish and let 'er eat.

http://www.autogeekonline.net/forum/...brid-pads.html

**roguegeek** · 12-04-2015, 02:16 AM

Originally Posted by kosmetikwerks

Maybe not! Here's an interesting mod done by a member of sister site autopia.Flex 3401 Modified Backing Plate

Ha! I love that idea and you know the factory bp will run just fine. I'm picking up two 4 3/8 plates now. One to keep factory and one to mod.

Mike Phillips · 12-04-2015, 09:55 AM

When I answered previously I was on my phone. I"ve been out here in Californial since November 27th. Today is December 4th. So I have not had a lot of time behind my computer with a larter monitor than what my phone provides.

We're in-between shootinig our TV show so I have some time this morning to jump on the forum and see what's going on. I chose to revisit this thread.

Now that I'm behind an actual monitor and have some time to look at the below pictures I have an observation.

In the below picture, the bolt is NOT supposed to go into the ADAPTER. It's supposed to go into the backing plate.

Originally Posted by kosmetikwerks

I'll let some of the pictures I took speak for itself!!

Below is a picture from an article I wrote on this forum and it's also in my Flex how-to book.

New 4" and 6" Backing Plates for Flex 3401

The protruding tabs lock into the slots on the interface plate and then both are bolted to the spindle.

HERE
See how the bolt goes into the backing plate. This then sandwiches the backing plate against the adapter to hold the two components to the tool.

The picture the OP is showing shows the bolt being attached to the adapter.

So maybe I'm not understanding the picture shared by kosmetikwerks?

**kosmetikwerks** · 12-04-2015, 10:05 AM

Originally Posted by Mike.Phillips@Autogeek

When I answered previously I was on my phone. I"ve been out here in Californial since November 27th. Today is December 4th. So I have not had a lot of time behind my computer with a larter monitor than what my phone provides.

We're in-between shootinig our TV show so I have some time this morning to jump on the forum and see what's going on. I chose to revisit this thread.

Now that I'm behind an actual monitor and have some time to look at the below pictures I have an observation.

In the below picture, the bolt is NOT supposed to go into the ADAPTER. It's supposed to go into the backing plate.

Below is a picture from an article I wrote on this forum and it's also in my Flex how-to book.

New 4" and 6" Backing Plates for Flex 3401

HERE
See how the bolt goes into the backing plate. This then sandwiches the backing plate against the adapter to hold the two components to the tool.

The picture the OP is showing shows the bolt being attached to the adapter.

So maybe I'm not understanding the picture shared by kosmetikwerks?

Hey Mike! Look a little closer at that picture. It actually melted then separated you can see the a bit of the backing plate that is left sandwiched between the bolt/washer and the adaptor. I took multiple pictures if you want to review kinda hard to see from that picture alone.

Mike Phillips · 12-04-2015, 10:29 AM

Originally Posted by Boejoula

Maybe I need to look into Mike's book on the flex because I use the flex on speed 6 for cutting all day with M105. I will try it on slower speeds and see how it does.

When I write how-to directions for using a tool I always recommend a RANGE of speeds not a single exact speed. (Except for the Porter Cable 7424XP and the Cyclo polisher. Normally for these two tools you'll WANT and need to be on the highest speed setting to do correction work)

The reason I recommend a range is because,

People are different

That said, the majority of time I use the Flex 3401 for correction work on on the speed 6 setting.

Why?

Because there's something to be said for SPEED.

I don't have the time to spend more time to do the correction step when I can get it done faster by spinning the pad against the paint faster and thus abrading the paint faster.

Mike aka smack recommends using slower speeds for his smack technique and if that works for him and anyone else that uses the slower speeds then that's perfectly okay. But my point is,

Sometime there's something to be said for SPEED.

I buffed this old 2-door Chevy out from start to finish in 5.5 hours. I could NOT have done it this fast using the 4 speed setting for the correction step. NO WAY.

1969 Corvette Stingray - Cobra Clay Mitt Review

I buffed out this old 2-door Packard in 5.5 hours from start to finish and there's NO WAY I could have done it that fast if I had doddled along on the 4 setting for the correction step.

3D HD Adapt and Poxy Review - 1940 Packard Streetrod detailed by Mike Phillips

Originally Posted by Boejoula

I think I'm going to stay away from the LC plates for a while, too.

Was thinking about getting them until seeing how many people have had problems.

I think you're discounting a perfectly fine product. There were issues with the 6" backing plates but there is not trend for issues with the 4" backing plates.

Originally Posted by cardaddy

Still can't figure the need for wide open on the 3401.

See what I wrote above about speed...

Originally Posted by roguegeek

That's too bad about those 4" backing plates. What's more unfortunate is you can only use the LC hybrid 5" pads on the LC 4" backing plate and not on the factory 4 3/8" backing plate.

Guess I wont be using those 5" pads.

I wouldn't be without the 4" backing plates because there's simply too many times with a 5" pad is the best size match for the panel to be buffed.

Going on 4 years now I teach a class at Mobil Tech Expo called,

How to turn your Flex 3401 into a money making machine

And part of the equation is having two Flex 3401 polishers. One set up with the factory backing plates to turn 6.5" Hybrid pads and the other set up with the 4" backing plate to turn 5" Hybrid pads.

I can also tell you that my friend Marius uses the 4" backing plates with 5" Hybrid pads a lot when buffing out Wayne Carini's car projects.

Originally Posted by wytstang

I am so glad I did not pull the trigger on the kit for BF sales.

There were 2 reviews on AG and both said they melted/busted. Instead I went with some 6.5 Hybrid pads to be safe.

Looks like that move was the right one.

Are you sure the 2 reviews you read for for the 4" backing plates and not the 6" backing plates?

Lake Country has discontinued offering the 6" backing plates. To be honest there was never a "need" for a 6" backing plate so it's no big deal the backing plate is no longer around.

What a guy needs is the factory baking plate that comes with the tool when you purchase it and the 4" backing plate in order to use the 5" Hybrid pads.