The hinges should be 6 way adjustible. In, out. Up, down. Left, right. Start adjusting all of the doors for clearance, paying attention to the in out first.

We did adjust the left/right and maxed out the spacing between the bumping doors. They still bump.

The hinges are Blum Compact 38C, bought from A&H Turf. I looked on the Blum website and found the planning brochure for this hinge. It said minimum reveal is 9/32". I confess I didn't measure our actual to that level of detail. I will do this evening when I get home.

OK, finally got back to this. We double checked that both the bumping doors max adjusted away from each other. The gap was 5/16" at the top and bottom, which is more than the minimum 9/32" requirement. But they still won't both open at the same time without bumping each other.

Ideas?

OK, lets talk terminology here for clarity. What exactly do you mean by ''bumping in to each other''? Where are they touching? Pics?

Is this a butt door? Did you allow the 1/4" for each door of the butt cabinet? A 30''W cabinet has two doors that measure 14 3/4"W, not 14 7/8"W.

Are the hinge side of each door "bumping" when you try to open both?

Easiest solution would be to buy 1 1/4 overlay hinges for those doors, as long as you've got clearance on the knob side of the door. What's the size of the door, and what's the opening?

I'm also a little confused here, are you talking back to back hinging?

If so, what would be the need to open both doors at the same time?

Yes, back-to-back hinging is the problem. The corners of the doors on their hinge sides are bumping when we open both at the same time. Which we'd do, in this case, when emptying the dishwasher (one cabinet holds plates, the other cups).

We put a couple washers in the hinge on the RH door to shift it an extra 1/8" or so, and now the corners just kiss each other when opening simultaneously, and they can be opened one at a time and remain open together without bumping. Gap between those 2 doors when closed is now 3/8".

To provide some of the other details of how I ordered the hinges for these:
LH cabinet is 28" wide, 25" opening, left side abuts wall.
Doors: 13 5/8" wide, with 1" overlay hinges on left and 1 3/8" overlay hinges on right. That leaves 3/8" reveal on left side (against wall) and 1/8" on right side.

RH cabinet is 30 1/2" wide, 27 1/2" opening, right side abuts window.
Doors; 15" wide, with 1 3/8" overlay hinges on left and 1 1/2" overlay hinges on right. That makes it flush on the right side, 1/8" on the left.

Sophie: if I'm understanding you correctly, that you need to leave 1/8" reveal on either side of the door for whatever's next to it, that's what I did.

Taylor: if I use 1 1/4" overlay hinges, I'll have 1/2" gap between the doors, and that's not full overlay, is it? Barker Door was very clear that 1/4" was the standard for full overlay: Barker measuring tutorial

You need to leave 9/32" next to EACH door, for a total gap between doors of 9/16".

I think you said you were at 3/8" between the doors? My full overlay doors are 1/2" apart between cabinets. They can open simultanously no problem, But, we're talking they just barely miss each other by a hair. :-)

So did I read these instructions/specs wrong?

Here's what Barker said:

And here's the Blum spec:

That doesn't look to me like you need 1/2" and 9/16" respectively. Unless there's a missing instruction that calls out the different requirement if you've got 2 doors with hinges butting together? Is that what I missed?

The good news, I suppose, is that out of 64 doors and drawers, I only have 4 pairs of doors that will butt hinges, so at least those are the only ones we'll need to shim/cheat to make work.

Well, Barker is telling you to use 39C hinges, which requires 7/32" minimum reveal (per door), which is a total gap of 7/16". That's well over the 1/4" total gap they tell you to allow. I think they owe you some new doors. But since you didn't buy the hinges from them, I don't know how far you'll get. Do you only have the problem with 2 doors? If so, I'd expect they'll make it right for you.

The Blum spec is stating that you need a minimum reveal of 9/32". That's for each door. I don't know what 1/2" you're referring to. Each door needs the space of 9/32" to open fully without hitting an obstacle.

Imagine that the wall in the above drawing (it's the part extending forward to the right of the hinge) is actually an open door on the adjacent cabinet. The door on the left needs 9/32" gap to not hit that other door when it's open. The blown-up image shows how the corner of the open door is to the right of where it was when it was closed. So a fixed object (in this case it's the open right door) needs to be at least 9/32" away from the edge of the closed door. The same holds true for the right door when it's opened. The right door, when closed, needs to be at least 9/32" away from a fixed object on the left side (which in this case is the open left door).

"Taylor: if I use 1 1/4" overlay hinges, I'll have 1/2" gap between the
doors, and that's not full overlay, is it? Barker Door was very clear
that 1/4" was the standard for full overlay: Barker measuring tutorial"

Maybe not, but your doors will work.
Switch one door that's "bumping" to 1 1/4 OL hinges, then adjust it out

catbuilder: re your point about the 39C hinges, if you're right, that I need double the specified 7/32", or 7/16" clearance total between 2 hinged doors, which based on my experience here is correct (i.e., the doors clear each other if I have twice the specified clearance), then Barker's instructions to leave 1/4" between doors is incorrect, as it's 3/16" shy of the requirement.

Here's an answer on the barker forums specifically dealing with back-to-back hinges, and Chad gives tips to shrink the gap from 1/2" to 1/4". 1/4" overlay answer. Sigh. I think I'll post a question there and see what he has to say about their errant instructions.

Taylor: Switching hinges as you propose would accomplish the same thing as shimming out the 1 3/8" hinge. It's clear that I'm not going to get "full overlay" with 1/4" gap as described. :-(

Thanks to everyone for helping me sort this out.

Simple answer: Reorganize your dishes.

Complicated answer, yes the clearance is for EACH door. It's additive, not singular. Changing one hinge to a partial overlay will do it.

Per Chad Barker: "Keep in mind that the compact hinges must have about 1/4" clearance on each side to operate properly" and on the Barker Door website: "Notes:

Make sure you have at least 1/4" reveal (gap between doors). If you go less than 1/4", then you may run into problems with the operation of the doors."

These statements are direct contradictions of each other. I agree that their instructions are incorrect, and that's why I think they owe you new doors (especially since as of at least 8 months ago they admittedly knew of the problem). The only way I see to maintain the 1/4" gap is to have all the doors next to each other open the same direction.

Make sure you have at least 1/4" reveal (gap between doors). If you go less than 1/4", then you may run into problems with the operation of the doors." That statement is used in conjunction with the photo (as posted by weedy above) which shows a door next to drawers. So it is correct in that you need at least 1/4". It would have been better if instead of door they said door/drawer, but it appears that on their website they often use the word door when they mean drawer..

This is a great thread since I never thought about clearance between doors and drawers. I hope weedyacres that you solve the problem. Please do share any updates.

Perhaps a monkey wrench in this thread:
I have some cherry cabinets that have the same Blum hinges, but they're 15/16th!

I'm also wondering if it might be easier for the OP to pick up some of the hinges used for seriously, 100% overlay. They're not blum (will have to check) but they bring the door forward (towards you) then open. These came on a cabinet I picked up at a reuse center and the doors really are, 100% overlay.

Here's Chad's answer:
"I do not work for Blum, nor did I design the hinges, but I assume that
the compact hinges are not really designed to have two back to back
doors being opened at the same time. This is just not a common
occurrence as one set of doors would typically be closed prior to
opening a separate set of doors."

He makes it sound as though my need is odd, but given the responses above, it seems to be known by the GW experts to allow double clearance when hinges back to each other. So I'm surprised that the experts at Barker aren't aware of it. And I'm a bit disappointed that they are sidestepping it instead of saying "good point, we'll update our measuring guides to warn others about this." Oh well.

I'm not going to hit them up for new doors or anything. We can remedy the issue on the 4 sets of doors that back up to each other. And I'm not so anal that I care about those doors being closer together in the middle than others in the kitchen. I'd rather live with that than paint 8 new doors. :-)

off the cuff but have you thought about planing a hair off the door?