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  #1  
Old 07-16-2021, 04:47 AM
JeremyL JeremyL is offline
 
Join Date: Aug 2020
Location: Maurertown,Virginia
Posts: 119
Default Well I join the reorder group….

It’s official, I have joined the “screw up a part and reorder it” group. Which I’m sure most all of us are in. The dreaded TE wedge countersinking got me. I’m not sure what happened, as to why it chattered so much but it did and vans tech support said “replace.” I was using the Cleveland wedge drilling device, on a drill press running at 450 rpm. My fix for this is going to be….. drop the rpm to the lowest it will go (300) rpm, I have purchased the single flute countersink bit, and decrease the depth by about 2/ 1 thousandths. I have included a couple pictures of the mess and one I thought was interesting from vans tech support. If you have any pointers, etc, I’d love to hear.
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  #2  
Old 07-16-2021, 06:02 AM
Robin8er Robin8er is offline
 
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Location: Socal
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Drill/deburr a scrap piece of mild steel the same diameter as the hole for the counter sink.

Clamp that underneath the aluminum and make the holes line up. The mild steel will serve as a guide for the countersink and will prevent wondering/chattering.

Aluminum will work too, but you will have to make a new one every so often as the hole becomes oblong from use.
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  #3  
Old 07-16-2021, 06:08 AM
BillL BillL is offline
 
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Location: Central IL
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Single flute will address the issues. It is only AFAIK a 1/4 drive not the 1/4-28 thread, but it really is no issue. I find a good variable speed hand drill gave me less chatter. You can easily look at the CS to see if it is aligned.

While drill presses seem like a good precision way to do all things, they have their own limitations. Details spared.

Variable speed hand drill with single flute. Practice on something else and mind your hand grip technique. I always held the drill with the grip up, not down like a pistol. Forearm line of action is more linear with the bit that way - just me . . . maybe mental but what ever works.

Oh- and mineral spirits or Tap-Con or kerosene as a lubricant can get smooth cutting with aluminum if nothing else works.
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Last edited by BillL : 07-16-2021 at 06:11 AM.
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  #4  
Old 07-16-2021, 06:23 AM
RVDan RVDan is offline
 
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Location: Frederick, MD
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Post number 2 has the answer. Anytime that you countersink to a near knife edge hole or beyond, the pilot can’t keep the bit centered. You need a guide, and the backup piece will do that if you clamp it to the work piece. That will work with a hand drill or with a drill press. On a drill press that doesn’t have excessive play, you can simply clamp the work piece down to get a good result.

Different bit types with some technique thrown in can improve the results, but IMO, never as good as stabilizing the pilot or the workpiece.
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  #5  
Old 07-16-2021, 06:23 AM
JeremyL JeremyL is offline
 
Join Date: Aug 2020
Location: Maurertown,Virginia
Posts: 119
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Quote:
Originally Posted by Robin8er View Post
Drill/deburr a scrap piece of mild steel the same diameter as the hole for the counter sink.

Clamp that underneath the aluminum and make the holes line up. The mild steel will serve as a guide for the countersink and will prevent wondering/chattering.

Aluminum will work too, but you will have to make a new one every so often as the hole becomes oblong from use.
This would be a good idea, but for me using the Cleveland device, it won’t workout. Excellent advice though if I didn’t have the device. Thank you.
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  #6  
Old 07-16-2021, 06:39 AM
JeremyL JeremyL is offline
 
Join Date: Aug 2020
Location: Maurertown,Virginia
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Quote:
Originally Posted by BillL View Post
Single flute will address the issues. It is only AFAIK a 1/4 drive not the 1/4-28 thread, but it really is no issue. I find a good variable speed hand drill gave me less chatter. You can easily look at the CS to see if it is aligned.

While drill presses seem like a good precision way to do all things, they have their own limitations. Details spared.

Variable speed hand drill with single flute. Practice on something else and mind your hand grip technique. I always held the drill with the grip up, not down like a pistol. Forearm line of action is more linear with the bit that way - just me . . . maybe mental but what ever works.

Oh- and mineral spirits or Tap-Con or kerosene as a lubricant can get smooth cutting with aluminum if nothing else works.
Thank you bill. I do indeed suspect that it is a pilot hole utilizing the 3 flute bit due to one side of the wedge was able to be countersunk with virtually no chatter. The chatter did not appear until I flipped the wedge over and tried to do the opposite side. So my new plan will be to use the 3 flute on one side , flip the wedge over and then use the single flute. The reason I would use both and not just the single flute is a minor design flaw in the single flute where the pilot breaks off on about 10% of the products. So I hope to minimize side load on the single flute. But we shall see .
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  #7  
Old 07-16-2021, 09:09 AM
Jslow2 Jslow2 is offline
 
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I would check your drill press for levelness/perpendicular to the chuck, it looks like, especially in the second picture, you are not hitting flat when you countersink. The countersink is wider on one side than the other. Maybe its the tool not flat, idk.

I am surprised they said replace, I could swear I've seen posts where they say its acceptable because it is sandwiched between two skins and has proseal in between.

I don't understand Vans picture, are you actually riveting to the countersunk wedge or are two skins doing most of the structural work and the TE wedge is just in between?

Picture of the tool I made from a practice kit to countersink the wedge.
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  #8  
Old 07-16-2021, 09:49 AM
JeremyL JeremyL is offline
 
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Quote:
Originally Posted by Jslow2 View Post
I would check your drill press for levelness/perpendicular to the chuck, it looks like, especially in the second picture, you are not hitting flat when you countersink. The countersink is wider on one side than the other. Maybe its the tool not flat, idk.

I am surprised they said replace, I could swear I've seen posts where they say its acceptable because it is sandwiched between two skins and has proseal in between.

I don't understand Vans picture, are you actually riveting to the countersunk wedge or are two skins doing most of the structural work and the TE wedge is just in between?

Picture of the tool I made from a practice kit to countersink the wedge.

I noticed that too, but that only happened on the back side countersink, so I assumed it was because the pilot wasn’t secure. But I will check the level when I get home just to be sure. I am also surprised they said replace it, seeing other pictures and similar problems but I dunno. To be honest I am sure it would be fine to install but it would bug the heck out of me if I did and they said replace. I’ll paste the quote of exactly what tech support said in regards to that picture….

**Tech support said:** “I would like to point out additionally, that the countersink depth for a nested dimple is a little different than what most initial builders might think. This diagram shows/indicates the feature:”
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  #9  
Old 07-16-2021, 01:00 PM
terrye terrye is offline
 
Join Date: Feb 2010
Location: Vancouver, BC, Canada
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Default Well I join the reorder group….

The Cleaveland jig although it holds the AEX at the right angle to keep the countersink perpendicular to the AEX surface, does NOT center the countersink pilot (thru hole way too big). So any play in your countersink cage and drill press spindle will show up as chatter in the cut. My preference is as previous advice, make a sacrificial backup piece (I made mine from aluminum angle) that has a #40 drill hole to keep the countersink pilot centered.
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  #10  
Old 07-16-2021, 01:13 PM
jacoby jacoby is offline
 
Join Date: Jul 2018
Location: WNC
Posts: 312
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It looks like your countersinks were too deep. You should be setting the cage to flush PLUS 7 clicks. In other words, the rivet should sit 0.007" below the surface. see section 5.5 and the drawing van's sent is why. If you do this, the center of the pilot just barely avoids busting out the other side. You only have a couple of mils to work with here.

You may also not be using enough pressure. I've found countersinks like to go slow and take big bites. YMMV.

If you're having trouble with part wander on the jig, try putting a piece of masking tape on the jig. It'll grab the AEX wedge once you start pushing on it.

Last edited by jacoby : 07-16-2021 at 02:14 PM. Reason: i had the wrong way on the csink!
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