# Dewalt DW621 Router cross threaded



## Vetteboy (Apr 17, 2017)

Hello all. I'm a newbie here and have a question that I have not been able to find the answer anywhere online. So I'm hoping one of you folks might have the answer. 

I have a DeWalt DW621 router that I have had mounted on my router table for years. A few weeks ago a friend stayed over as a house guest for a few days. As I was working on a (very simple) project I asked him to change the bit on the router for me. Well, I was distracted with what I was working on and was not paying attention to what he was doing. He owned a kitchen and bath remodeling shop so he knows his way around wood working tools, or so I thought. To make a long story short, he cross threaded the shaft so bad that I can't get the collet in properly. I need to buy a proper size die so i can attempt to re thread it. Does any one here know the specs on the threading for that router? DeWalt does not seem to know. They want me to replace the part. Which is basically the motor to the tune of $214.00. I can get a bran new router for not much more than that. Any help or suggestions would be greatly appreciated.


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## Herb Stoops (Aug 28, 2012)

A real Bummer. Sorry to hear about that. Is it the shaft or the nut? or both? 
Dewalt always had a good CS dept., wonder if you could get to the repair dept. and see if they have a fix. Or get a hold of an independent repair shop and see if there is a good fix.
Herb


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## Semipro (Mar 22, 2013)

Take it to a repair shop if they can not fix it I think your just going have to replace it.
Usually these shops have seen it before and know how to repair it or they also know it can't be repaired


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## Tonto1 (Nov 10, 2016)

Have you tried a thread gauge? I bet you can match it with one even it's damaged bad. Then buy that dye & try to cut it to restore the thread pattern. That's what I would do. Just go slow & use oil. If it is taking off too much metal, stop & try to get a nut started, that my reform the rest of the pattern without cutting more steel. Lots of oil! Worth a try!


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## DesertRatTom (Jul 3, 2012)

We have a local DeWalt shop even up here in the desert. The guy seems to really know tools, so that's where I'd go with it. The collet is a critical part and has to be cinched up just right, so I'd be very cautious about a home fix, unless you've done this kind of thing a lot.


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## Cherryville Chuck (Sep 28, 2010)

There's a really good possibility that it's a metric thread. I have an old DW 610 which has been discontinued for years and it has a metric thread. I think the 610 was around 19mm and a fairly fine thread pitch. If both the shaft and the collet are damaged you'll need the proper die and a bottoming tap as well. That could get pretty expensive. If it is metric it may be difficult to find a shop that already has the right sizes and if they don't they'll probably pass the cost of buying them onto you.

I've managed to fix the male threads with small triangular files and even a hacksaw on the odd occasion. If you can get the start of the first thread fixed you might be able to straighten the damage out but it will be much weaker than before and there is a possibility that it will strip out later. Harbor Freight sells a set of 12 very small files that are different shapes and they would work well for fixing the male thread and they only cost a few dollars. You may also need to try and repair the start of the internal thread and that will be a little harder but those files may allow you to scrape away at it and eventually succeed. Don't try to force it unless you are absolutely certain that the threads are lined up and tell your friend that if it ain't going easy to stop and start over or just leave it alone next time.


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## roxanne562001 (Feb 5, 2012)

I have used thread files to restore cross threads. You just need to know how many threads per inch that are cut on the shaft. Or you can match the file to the threads on the shaft then file out the area that is cross threaded. Here is a link to thread files on Amazon. https://www.amazon.com/Nicholson-Th...=2025&creative=165953&creativeASIN=B001T4KRHC Then you may have to buy a new collet nut as well.


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## MEBCWD (Jan 14, 2012)

roxanne562001 said:


> I have used thread files to restore cross threads. You just need to know how many threads per inch that are cut on the shaft. Or you can match the file to the threads on the shaft then file out the area that is cross threaded. Here is a link to thread files on Amazon. https://www.amazon.com/Nicholson-Th...=2025&creative=165953&creativeASIN=B001T4KRHC Then you may have to buy a new collet nut as well.


I would get a thread gauge and check the pitch, then use the corect file to repair the threads on the shaft. I would also buy a new collet nut because it would be hard to repair the internal thread.

Here is a link for a thread guage and two more choices on files:

https://www.amazon.com/GOCHANGE-Thr...8&qid=1492523564&sr=8-1&keywords=thread+gauge

https://www.amazon.com/TF-2-Thread-...2522914&sr=8-1&keywords=thread+cleaning+files

https://www.amazon.com/TF-1-Thread-...2522914&sr=8-2&keywords=thread+cleaning+files


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## sunnybob (Apr 3, 2015)

I wouldnt try to repair that.
If that thread breaks loose and the cutter comes out........
doesnt bear thinking about.
Give it to your friend and say "you broke it, you pay for the replacement"


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## MT Stringer (Aug 15, 2012)

Welcome aboard.

I don't have a solution, but I do have a suggestion.

I have a Musclechuck that fits my Bosch 1617 router. I am having a brain freeze on the inventors name - John DeRosa or something like that. I would bet he knows what the thread pitch is for any of the routers he has built the Musclechuck for. That would be a good source of information if the OP could get in contact with him and explain his problem.

Found some info on the inet...>
CNC Router Chuck | DeRosa Engineering | Musclechuck Assembly

Here is a link to a thread discussing router shaft extensions.
http://www.routerforums.com/starting-off/45721-extending-router-bit-shaft.html


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## woodknots (Mar 7, 2012)

I'm going to echo Bob's sentiments - sharp things going fast are scary - I'm not sure I'd try to repair that shaft myself or at all for that matter. The cost of a replacement is hardly worth the possible injuries from a flying bit.


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## hawkeye10 (Jul 28, 2015)

You might try finding a used one on Craigs List. More than likely your best bet is to just buy a new router. I buy a lot of tools from CPO and they have very good customer service. Also don't be afraid of their factory reconditioned tools.

Routers and Trimmers | CPO Outlets


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## luv2shapethings (Apr 28, 2017)

*Thread files = success!*



roxanne562001 said:


> I have used thread files to restore cross threads. You just need to know how many threads per inch that are cut on the shaft. Or you can match the file to the threads on the shaft then file out the area that is cross threaded. Here is a link to thread files on Amazon. Then you may have to buy a new collet nut as well.


Thank you, thank you, thank you. :grin: Only the first thread on the shaft was damaged on my router and the collet nut was fully intact. I purchased the recommended thread files from Amazon and after following the good threads it cleaned the damaged one and my collet nut threads and tightens perfectly. There is no slack in the nut and I am confident it does not pose a safety risk.

Thank you again!

--Jim--


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