Warning regarding Collet Adapters

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danimal
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Warning regarding Collet Adapters

Post by danimal » Wed May 28, 2014 4:28 am

I bought a collet adapter a little while back and it seemed to work great. It adapted my Makita RT701c collet down to 1/8" and I could use all the end mills that I had for my dewalt that I previously used. It worked fantastic... until yesterday. I don't know what happened or what changed but all the sudden it started to pull the end mill out of the adapter as it was running.

I know that up cut end mills will do this, but I have never had a problem up to this point. The first mill I used just randomly snapped before I knew what happened. I thought nothing of it because I have broken quite a few end mills these last years, just not during normal operation. I got out another one and put it in and started the job over. It started fine because it was mostly milling air, but then as I watched it, it started being drawn out of the collet. I tried to hit the e-stop, but did not make it in time. Snap.

So I put in a third end mill and tightened the hell out of it. But about 30 seconds into the job, it started getting drawn into the material. I e-stopped it and caught it just in time. Feeling a little frustrated, I re-did my g-code and changed my tool paths from climb to conventional thinking that was either the problem, or contributing to the problem. It ran for about two full passes, and just as I sat back down it drew it into the material and snapped a third end mill, embedding a chunk of it in the wall behind my machine. Oh yeah, wear eye protection.

To make a short story long, I am throwing away my adapter and will never buy another, because they can randomly stop working. This is made worse when using up-cut end mills, but I imagine that any mill coming loose in your machine is not going to end well. I made sure all three times that the adapter was installed correctly, fully seated in a clean collet, and that the assembly was tight. The only thing I could figure is that it was just loose enough the first time to spin the end mill, immediately ruining the adapter. But even this case is strange because it was still very tight when I disassembled the collet the first time to remove the broke end mill. Take from it what you will, I am just putting my experience out there as a warning.
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WillAdams
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Re: Warning regarding Collet Adapters

Post by WillAdams » Wed May 28, 2014 10:11 am

The tolerances are really small --- probably it was a worst-case conjunction of wear in the adapter, the collet, the collet housing and things happening to fit together so that either things were not aligned or could not be tightened.

I wonder if one shouldn't make it a habit to remove the bit and adapter on a regular basis, counting on the reassembly rearranging the parts for even wear.
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
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Auarhau
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Re: Warning regarding Collet Adapters

Post by Auarhau » Wed May 28, 2014 10:47 am

This happened to me too with an original dremel. I now changed to a Kress with precision collets. I can't speak much for how it operates yet, but one thing was very apparent. The precision collets have a very tight tolerance. At first I thought my 1/8 bits was too large for the 1/8 collet, but it fits just barely when you insert it properly. How was the quality on the adapter you used?
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scott216
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Re: Warning regarding Collet Adapters

Post by scott216 » Wed May 28, 2014 5:15 pm

Auarhau wrote:I now changed to a Kress with precision collets.
I never heard of Kress. I just took a look at their website and these seem pretty nice. Which Kress do you have?
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Little Hands
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Re: Warning regarding Collet Adapters

Post by Little Hands » Wed May 28, 2014 6:05 pm

All,
Try this site http://elairecorp.com/routercollets.html, after market collets for Bosch, Dewalt, Porter Cable (sorry Makita?), I use them with my Bosch Colt & they work great. With that said, when changing bits I clean the collet & bit with an alcohol wipe, maybe over-kill but. In the past, using hand held routers, I have found using adapter/collet combo's you have lots of wear/fatigue on both parts.

megeshg
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Re: Warning regarding Collet Adapters

Post by megeshg » Thu May 29, 2014 7:24 am

danimal, are you on the list for the 1/8 inch collet bulk buy?

Maybe look into that?

WillAdams
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Re: Warning regarding Collet Adapters

Post by WillAdams » Thu May 29, 2014 10:06 am

Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
Nomad 883 Pro #596 (bamboo)

danimal
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Re: Warning regarding Collet Adapters

Post by danimal » Sat May 31, 2014 12:13 pm

megeshg wrote:danimal, are you on the list for the 1/8 inch collet bulk buy?

Maybe look into that?
Dang, I did not even see that thread!

Not to worry though, I just went and ordered a bunch of 1/4 shank end mills so I don't have to fuss with the adapter. After last week I really don't have that many 1/8 shank end mills anyway.

Is the buy still open? Anyone have one that they want to get rid of?
Shapeoko # 1458

RT0701C Spindle || dual y motor || x axis nema23 with custom carriage 1000mm length || z axis nema23 linear rail upgrade with 1/2-10 ACME

WillAdams
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Re: Warning regarding Collet Adapters

Post by WillAdams » Sat May 31, 2014 2:14 pm

See the May 30 update: http://www.shapeoko.com/forum/viewtopic ... 761#p26731
Mark said that he rounded our batch up to 25 total pieces, and would offer the remaining 9 pieces on their website, first come first served, for $19.75 each. If you contact him via the sales E-Mail above and mention that you heard about the custom 1/8" collets for the Makita RT0701C Trim Router on the Shapeoko forums, he will give you the lower $17.50 price break we got for the first group order.
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
Nomad 883 Pro #596 (bamboo)

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