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Setting Cherry Max Rivets

Thanks for posting the link, David! Looks like a great tip. Is there a place on Van's website where videos like this are posted?
 
Anyone else at this stage yet? I?m having horrible luck with theses rivets even following the video, only about 1 in 3 rivets are acceptable.
 
Having a lot of trouble too, even using a cherry max hand puller. I tried the Van way of lubing the stem but no joy. Have had to order more. Thinking of going to find a pneumatic cherry max puller.
 
Here is a good explanation of how CherryMax Rivets work, and what happens when one is properly set. http://www.cherryaerospace.com/docs/catalogs/CA-1011.pdf
Before the CherryMax blind rivet was introduced, The CherryLock rivet was the structural blind rivet of choice. The main drawback to the CherryLock rivet was the requirement for a specialized, expensive puller that would set the mandrel lock ring during the pulling process. This lock ring is important as it positively locks the mandrel in place and allows the rivet to develop design strength. The CherryMax rivet uses a washer ("anvil") to set the lock ring, so a standard "pop rivet" puller can usually be used to set them. This is one reason why CherryMax rivets are approved on Standard Category aircraft size-for-size with solid rivets.
To easily remove a CherryMax rivet, the lock ring should be ground away, with a pencil grinder or a high-speed grinder and cutoff wheel. The (usually steel) mandrel can be driven out and the rivet head drilled as with a solid rivet.
 
Thought I would share my experience setting the CR3213-4-08 cherry max rivets on the RV12is fueslage spar assembly. For starters, I have set many cherrymax rivets over the years with zero issues. I have the cherrymax hand tool, and lubricated the rivets like in the video. Despite all of this, I was getting maybe 1 in 4 rivets to set properly. Finally walked away and decided to order a new batch of rivets. Not cheap, but was able to get them for $1 each when ordering 50 through Aircraft Tool Supply.

Rivets came today. Not a single failure with the new batch, setting 30 rivets. What a difference, much to my relief. Not sure why a different batch mattered, but it did. Visually, I could not tell the difference between the two. So if you are following the video and still having issues, try ordering another batch from a different source.

One other comment, for those who are not familiar with a properly set cherrymax, make sure you learn and check these rivets. They need to be properly pulled and locked to get full strength.
 
Aaron, did you lubricate the new batch of rivets like the video shows, or did you just pull them the way they came from the factory?

Thanks,
 
I lubricated them like the video. Did the same with the original Van?s rivets, but they would still not set properly.
 
I lubricated them like the video. Did the same with the original Van?s rivets, but they would still not set properly.

Thanks! I followed the instructions in the video but also need to reset some of the CherryMax rivets in that spot. Very frustrating!
 
Like most people I had a lot of fun with the long cheryymax rivets, they were a real PIA. What seemed to work best is to pull them REALLY slowly with a manual puller. The air puller didn't work at all (it pulls too quick). I had to replace almost all of them twice before I finally got the hang of it.

BTW - i had no idea about the lubrication hack, that might have made it somewhat easier.
 
I had the same experience AaronG had. I'm a first time builder, so I thought it was me, but I have a friend who has built a 12 before, has 30+ years of experience in the industry and has access to an official CherryMax pneumatic puller :) Even with all of that, we had a high failure rate pulling these rivets (with the lubrication trick).

I think for whatever reason batches of these rivets simply fail to pull correctly. With a new batch they pulled fine.
 
I had the same experience AaronG had. I'm a first time builder, so I thought it was me, but I have a friend who has built a 12 before, has 30+ years of experience in the industry and has access to an official CherryMax pneumatic puller :) Even with all of that, we had a high failure rate pulling these rivets (with the lubrication trick).

I think for whatever reason batches of these rivets simply fail to pull correctly. With a new batch they pulled fine.

Isn't this all ironic? These things are stupid expensive and are "Aviation" quality. You'd think quality control would be better.
 
Well, I just got to this part of the 12iS fuse build, and just let me say, #&@$! Cherry Max rivets. :mad:

Like others, this is what I got in return for my lubrication efforts:
cJdsuCql.jpg


Switching from the pneumatic to a slow manual pull helped a little, but still not perfect.

Is there any reason we can't finish setting the ^%$! things with a squeezer? For that matter, can't we just use squeezed rivets in the first place?

(EDIT: To clarify, I wasn't trying to squeeze the aluminum body of the rivet to set it like an AN470, I was simply trying to finish pushing the stem through to it's final locked position. I think this is a valid solution, but I should've used a flat set on the shop head, to emulate the install-washer, instead of the domed set I used, and I should've not squeezed so much. Mechanically, if done properly, there should be no difference between pulling the stem through vs pushing it through)

Here's what they look like after a good post-pop squeeze, back and front. Are they good, or do they need replaced? (EDIT: Yeah, not happy with those, they will be replaced)
L9ZDcpwl.jpg

sJvmyKml.jpg
 
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The Cherry rivets are used because they are stronger than AN470 rivets.
I don?t have time to go into a long description of how they are designed but if oh do a bit of research today will find that what you did to improve their installation likely did nothing and might hav even reduced their strength.
Main point, don?t assume that just because they are both called rivets, that what is relevant to one is relevant to the other.

I didn't assume, that's why I asked the question. They were already not set properly, so what I did either finished setting them or it left them still in need of removal, so no harm no foul. I'm looking for advice and useful information, not scolding. Thanks.
 
Had much better luck on the second side by adding a last-second squirt of WD-40 to the tip and being very very careful with the hand puller. I was rewarded with a very satisfying double-pop and what look like properly set rivets according to the manual. Perhaps WD-40 would have worked better for the pre-lube than the 3-in-1 oil I used?

(Note there is one 'bad' rivet here that I post-squeezed)
SIKxsQcl.jpg

ZHrQPyil.jpg
 
I didn't assume, that's why I asked the question. They were already not set properly, so what I did either finished setting them or it left them still in need of removal, so no harm no foul. I'm looking for advice and useful information, not scolding. Thanks.
Well, ok then. You had already done it and then asked.

Ok deleting my post
Maybe someone else an help
 
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Well, I just got to this part of the 12iS fuse build, and just let me say, #&@$! Cherry Max rivets. :mad:

Like others, this is what I got in return for my lubrication efforts:
cJdsuCql.jpg


Switching from the pneumatic to a slow manual pull helped a little, but still not perfect.

Is there any reason we can't finish setting the ^%$! things with a squeezer? For that matter, can't we just use squeezed rivets in the first place?

Here's what they look like after a good post-pop squeeze, back and front. Are they good, or do they need replaced?

The good news is that the ones that aren't fully set are trivially easy to remove - you can easily drive out the mandrel and then drill the center of the rivet to remove the manufactured head/punch out shaft. Trying to get a fully set one out teaches you very quickly WHY they are stronger than regular rivets.
 
The good news is that the ones that aren't fully set are trivially easy to remove - you can easily drive out the mandrel and then drill the center of the rivet to remove the manufactured head/punch out shaft. Trying to get a fully set one out teaches you very quickly WHY they are stronger than regular rivets.

Well the ones in the bottom row weren't supposed to be there, which I realized after running short of rivets lol, so I will learn right now just how much pain I'm in store for. :eek:
 
Well the ones in the bottom row weren't supposed to be there, which I realized after running short of rivets lol, so I will learn right now just how much pain I'm in store for. :eek:

The trick is to get a punch onto the mandrel and drive it out. It's possible to very carefully drill into the center of the rivet but the mandrel is very hard steel, so the bit wants to slide off center into the softer aluminum. So I found two ways to help this: Use a very sharp bit in a rivet removal tool (works only on universal head rivets) to get a start on the center, then drive mandrel out (like a 1/16 punch IIRC). Or use a hard steel punch with a tapered point to get a start on the center part of the rivet. Both styles have a locking ring which can be worked out, but I never had any luck with that without ether a good drill into the center or punching out the mandrel.


Another approach:

https://www.google.com/search?q=dri...me&ie=UTF-8#kpvalbx=_OX5uXua6PKKq_QbvtpWYCg24
 
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Thanks Turner. I wasn't looking forward to it, but I must've gotten lucky. All I did was give 'em a few god whacks with a spring-loaded center punch then drill out a spot for the regular punch to snap the head off and punch out the shop-head. Not going to become my favorite past-time, but not what I had feared. Holes aren't even wallered out. (Note, some of the removed rivets were 'bad' post-squeezed, but they didn't seem any different to remove from the properly set ones) Of course now that I've said this all future removals are sure to be pure agony. :rolleyes:
hdqc1K4l.jpg
 
will the Milwaukee electric rivet tool work with Cherrymax

I'm just about to install the doubler on the wing and it has one Cherrymax rivet which is a type I have never installed. After researching through the forum, I see that some are having better luck pulling slow with a manual puller (after lubing). Does anyone have any experience on CherryMax rivets with the Milwaukee M12 puller? It works well for the LP3-4.
 
It works

I'm just about to install the doubler on the wing and it has one Cherrymax rivet which is a type I have never installed. After researching through the forum, I see that some are having better luck pulling slow with a manual puller (after lubing). Does anyone have any experience on CherryMax rivets with the Milwaukee M12 puller? It works well for the LP3-4.

I've used the Milwaukee rivet gun, and it set all the Cherrymax rivets I had to install perfectly.
 
I've used the Milwaukee rivet gun, and it set all the Cherrymax rivets I had to install perfectly.

Makes sense, that gun has a much slower controlled pull compared to a pneumatic.

For the lube, I recommend WD40 or something with a similar thin consistency. 3-IN-ONE oil did not work well for me; I assume it was too thick/viscous. ymmv
 
I'm just about to install the doubler on the wing and it has one Cherrymax rivet which is a type I have never installed. After researching through the forum, I see that some are having better luck pulling slow with a manual puller (after lubing). Does anyone have any experience on CherryMax rivets with the Milwaukee M12 puller? It works well for the LP3-4.

Inconclusive because there was also a lube change, but we had poor results with M12 puller on the Cherrymax rivets that go in the fuselage bulkhead. Better results were had with the manual puller. Like I said, a lube change and bit of process adjustment was also involved so it may not be the puller so much as the lube. Once I was getting decent results I didn't want to go back and experiment much.

There were so many bad rivets that we had to order a box of replacements so I'll tinker more once those are here. My suspicion, like others you can find with some searching, is that the batch of rivets can make a big difference.
 
Inconclusive because there was also a lube change, but we had poor results with M12 puller on the Cherrymax rivets that go in the fuselage bulkhead. Better results were had with the manual puller. Like I said, a lube change and bit of process adjustment was also involved so it may not be the puller so much as the lube. Once I was getting decent results I didn't want to go back and experiment much.

There were so many bad rivets that we had to order a box of replacements so I'll tinker more once those are here. My suspicion, like others you can find with some searching, is that the batch of rivets can make a big difference.

Anyone with experience from Cherry rivets supplied from Aircraft Spruce? I ordered some CR3213-4-2 CHERRYMAX RIVETS from them. Hope to find someone with the G-27 pop rivet tool, or anything else that would certainly work to set them properly.

Edit: Punched one of the old ones out, and drilled a #30 hole in a 2x4 about 7/16" deep, and tapped the mandrels partially back out, for all 15 rivets I bought. Put them all back in the plastic bag that Aircraft Spruce ships them in, and then sprayed a blast of LPS-2 in the bag, and juiced all the rivets. Friend has a Craftsman manual puller, along side a couple of pneumatic pullers. It took 4 pulls for the manual riveter to finally "grab" the mandrel, then it pulled tight. Another "pop" and the mandrel came off. Got a good nice, tight rivet in place now. LPS-2 and the current batch of rivets from Aircraft Spruce work great. About $0.65 a rivet, plus shipping, on orders of either 50, or 100 or less, I think, then it's 50c a pop. I bought 2 new 500-5 6 ply Airhawk tires and some window cleaner, with the rivets, so the shipping was free.

Really feels like getting this plane, and going through it, is practically doing an annual inspection on it, just for my piece of mind.
 
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