# porta cable 7800 type 3... how to get the head off



## 2k2wranglerx (Feb 21, 2012)

Hey guys,I'm sorry about the cross post. i'm new here.; i have a porta cable drywall sander and i can not figure out how to get the head off.  It looks simple enough, and i've pulled the exploded view of it, but i just want to make sure i'm doing this right before i gall something up.<br><br>I'm trying to twist it off like it screws down on the mounting post.  i just want to make sure there's no snap ring or anything that needs removed first.  <br><br>here's the cluprit that i'm talking about:<br><br>







<br><br>we had it worked on at porta cable and the first time we went to go use it it was burning up the plastic locking nuts for the sand paper.  you can hear that the bearing out at the end is whining and it gets hot out by the end.  I'm pretty sure that bearing is toast. <br><br>Rather than having to always drop these off at porta cable to be worked on, i'd like to stock a few parts so i can always repair them when they break.<br><br>any input or advice would be very much appreciated!<br><br>Thanks!<br>


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## Jason (Feb 27, 2011)

Yep, sounds like the typical bearing issue. Can't believe they continue to install a $.05 part in such a "quality" tool. 

The bearing is a 6001 or 6008 double backed/sealed... can't remember which. I installed an NSK which has been going strong for years.

The backing plate simply screws off, as I recall. You'll need both internal and external circlip pliers to access the bearing once the backing plate is removed.

One of my machines had a circlip holding the bearing on the spindle but the other had the bearing pressed onto the spindle, so I had to buy a new spindle for it too. Sounds like you might be up for a retainer plate if the threads have melted. 

If the motor has been straining to turn the head before you discovered what was going on, it will have stressed the drive cable so you might want to replace the cable, or at least inspect it, before it ruptures and costs you a cable sheath.

Hope this helps.


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## 2k2wranglerx (Feb 21, 2012)

That helps a lot. I just wanted to make sure before I put a lot of tq on it to get that head off. I'm at the shop right now with limited tools do tomorrow I'll try again with a real set of tools from home.

Thanks again


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## VANMAN (Jan 14, 2011)

2k2wranglerx said:


> Hey guys,I'm sorry about the cross post. i'm new here.; i have a porta cable drywall sander and i can not figure out how to get the head off.  It looks simple enough, and i've pulled the exploded view of it, but i just want to make sure i'm doing this right before i gall something up.<br><br>I'm trying to twist it off like it screws down on the mounting post.  i just want to make sure there's no snap ring or anything that needs removed first.  <br><br>here's the cluprit that i'm talking about:<br><br>
> 
> 
> 
> ...


 Put a srewdriver in the slot 2 hold it and simply turn the disk anti-clockwise with ur hand and it will slacken of! Hope this helps:thumbsup:


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## Jason (Feb 27, 2011)

2k2wranglerx said:


> That helps a lot. I just wanted to make sure before I put a lot of tq on it to get that head off. I'm at the shop right now with limited tools do tomorrow I'll try again with a real set of tools from home.
> 
> Thanks again


I remember some trouble cracking the tension on the threads. Always managed it with a jumbo flathead and a few profanities tho.


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## gazman (Apr 29, 2011)

I have used a G clamp to stop the disc from rotating. Then used a large screwdrive with a square shaft and a spanner on that shaft.


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## gazman (Apr 29, 2011)

This is what I meant. Dont tighten the clamp to much just enough to stop it from turning.
Then use circlip pliers to remove circlip.
Then the bearing and the shaft will just pull out.
the bearing will press off the shaft. You can use a vice as a press if you dont have one.

The part number over here for the bearing is SKF 6001-RSH.


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## Jason (Feb 27, 2011)

gazman said:


> This is what I meant. Dont tighten the clamp to much just enough to stop it from turning.
> Then use circlip pliers to remove circlip.
> Then the bearing and the shaft will just pull out.
> the bearing will press off the shaft. You can use a vice as a press if you dont have one.
> ...


Funny how we've all become mechanics and owners of circlip pliers for the sake of PC's choice in bearings, and it's been going on for years and years and years. They're not bad machines EXCEPT FOR THE BEARING, PORTER CABLE, you jackasses! That company is just asleep at the wheel.


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## silverstilts (Oct 15, 2008)

I have found that spraying the threads with some WD-40 or deep creep and let it sit for a minute you can just hold the screw driver on the end and spin off the disk works great. The lube softens any build up in there and being the threads are coarse the lube penetrates fast if it is seized together. Getting the bearing off I use a deep socket set it in there and tap it till the bearing falls out. I wonder if a needle bearing would hold up longer than the ball bearings?


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