Dewalt 7″ Grinder

I was out hitting up some flea markets with Chris when I came across a used Dewalt 7″ grinder for a great price.  I plugged it in and ran it before purchasing in the store.  I didn’t hear any odd noises or feel anything abnormal while running the grinder.  Satisfied that nothing seemed wrong, I purchased it and brought it home.

Overall, the grinder was it good condition.  The first issue is that the outer cover of the cord had broken and been wrapped in tape.  This isn’t a major issue but it could cause problems in the long term.  The other issue is that the end of the cord had been cut off and replaced with another plug.  The “repair” just looks pore and I really don’t trust it not to short out at some point.


I cut off the tape to expose the break in the cord sheath.  The wires underneath were still in good condition and didn’t require any work.


I thought about how to fix the break in the cord.  I could have cut the cord before the break and opened the grinder to reattach the cord.  As the wires were still good I decided to use some heat shrink tubing to repair the sheath.  Normally, I couldn’t repair the sheath in this fashion because the heat shrink tubing wouldn’t fit over the plug.   I planned to cut the plug off anyways, so this wasn’t an issue.  Below is the piece of heat shrink tubing I used.


I slipped the heat shrink tubing up into position and used a lighter to shrink the tubing into place.


Next, I put a new plug on the end of the cord.  I’ve covered putting a plug on a cord before so I’ll just show the final result.  I finally bulk ordered some replacement plugs off of Amazon instead of buying them one at a time from the local store.


The grinder looked like it’d never been cleaned before.  All of my tools aren’t pristine, but I don’t like tools that get you dirty just by picking them up.  So, I used some Simple Green and an old tooth brush to clean it up some.


That’s it.  Low cost used grinder and simple fixes.  What could be better?DG7 DG8


After posting the above, I received a comment from someone named Jack who pointed out that he didn’t like my repair of the break in the cord sheath.  He didn’t say why but it started me thinking about it.  I decided that the use of heat shrink tubing probably wouldn’t last very long before cracking or breaking.  It also wouldn’t do a adequate job of insulating and handling the loads that is the purpose of the sheath.  Since I try to make my repairs to last I decided to fix this issue.  I opened the grinder, cut the cord after the break in the sheath, and reattached the cord to the grinder.  I didn’t get pics of the process but do have a pic of the repaired cord.


This entry was posted in Restoration, Tools. Bookmark the permalink.

3 Responses to Dewalt 7″ Grinder

  1. Jack says:

    Hi certainly a machine used and ‘repaired’ by a moron prior to your buying it. You have not done a correct repair on the damaged cable adjacent the flexible rubber entering the ‘handle’ …don’t like it at all. As well, flame should be a little more distant on heat shrink and always moving.That cord should have been shortened, ‘megger tested’ and then if ok repaired inside the item in fact the whole business would have been better and cheaper if you’d bought a new cord or even a short, industrial grade extension lead and cut it to length reconnecting it exactly as Dewalt did inside the item . Did you use the same colour coding to new plug? I am perplexed at why you left the stuffed disc on there when cleaning the grinder, that said it is better to clean electrical equipment with cleaner applied to a rag so none can get inside the unit.

    • davidjbod says:

      Jack, It is possible that the heat shrink tubing will fail in its use to repair the cord sheath. It is probably stiffer than the rest of the sheath and could crack over time. If it does will cut out that section of the cord and reattach it inside the unit. I haven’t heard of Megger testing before and looked into it a little bit. It looks like an appropriate test to run in this case but I do not have access to a Megger. I’m just a guy working on my own tools in my garage. Yes, I have connected the cord to the plug correctly. When cleaning the grinder I first cleaned the plastic and then the metal end. I started with the plastic end and had simply not removed the disk when the picture was taken. Later, when I started to clean the metal end I removed the disk. When cleaning I sprayed the cleaner onto a rag and/or toothbrush as I did not want to spray the grinder directly for the reason you cited.

      Thanks for your comments,

    • davidjbod says:

      Jack, I thought some more about the use of heat shrink tubing to repair the break in the cord sheath. I decided that it probably wouldn’t last in the long run and repaired it by cutting out the bad section and reattaching it inside the grinder. I’ve also amended my post.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s