Baffle Oil Cooler Angle Support

[skelrad]

I'm putting together the baffles and planning out my oil cooler support (9A). Sounds like people have pretty good success beefing up the outer baffle corner with a piece of 1" aluminum angle, as well as supporting the inside cooler flange with a cylinder or boss mounted support that creates a triangle to the cooler.

I don't have any 1" structural aluminum angle on hand. For this use, would the garden variety angle from the big box store be okay, or should I put everything aside until I can order a chunk of structural angle?

 

[PhatRV]

The hardware store angle doesn't have the inner radius to relieve the stress concentration. I made my own angle by bending from 0.032 aluminum sheet. I made two angles, and laminated them to the factory baffle kit.

 

[scarlson]

I'm putting together the baffles and planning out my oil cooler support (9A). Sounds like people have pretty good success beefing up the outer baffle corner with a piece of 1" aluminum angle, as well as supporting the inside cooler flange with a cylinder or boss mounted support that creates a triangle to the cooler.

I don't have any 1" structural aluminum angle on hand. For this use, would the garden variety angle from the big box store be okay, or should I put everything aside until I can order a chunk of structural angle?

You can also forego the baffle reenforcement and mount the oil cooler on the firewall. That location also gives you the option of a bigger oil cooler. I have a 9a with a Titan IO-370 and the 7 row cooler was not adequate in the Summer months.

 

[BillL]

I wanted to get flying and just reinforced for my cooler. It was a coin toss though. Here is a couple of photos that show the areas that get reinforced. Imagine the head orbiting on the end and taking the cooler with it. The baffle is stiffened to connect with the head screws. Then the end of the cooler can wag -pivoting on the vertical attachment to that end baffle (reinforced by vertical .063" angle). The rod connects for that motion - closer to the center of the cooler. For a larger cooler, the remote mount is unquestionably needed. My engine and oil cools just fine w/o oil jets on the pistons. (a tradeoff to be sure).
All seems to be doing well at 300+ hrs. Fingers crossed.

Edit#1: BTW the angle is 6061T6 (35ksi yield ) aluminum, a bent .063 of 2024 (39-40 psi yield) would be stronger (60ksi ultimate), but the hardware store aluminum is relatively weaker (6063 T52 21ksi yield) and would be prone to fatigue failure at the root intersection. Aviation angle has a generous radius for that reason.

Be sure to torque the baffle screws to the head. I had them (2) come loose and fall out. Only 5 hours since last " inspection". - -Like Walt says, "stick a torque wrench on it " to be sure it (anything) is tight. All these screws are now on my list for yearly CI.

Edit#2 - added yield strength of 6061 T6 aircraft aluminum and 6063 T52 architectural aluminum. 5/14/25

 

[skelrad]

The hardware store angle doesn't have the inner radius to relieve the stress concentration. I made my own angle by bending from 0.032 aluminum sheet. I made two angles, and laminated them to the factory baffle kit.

Sorry, that's what I meant by "structural" angle vs the Home Depot variety. I wasn't sure if the radius mattered in this scenario. If it's questionable, I'll just wait for the real deal to arrive. Onlinemetals.com has been a winner for me during this build!

 

[rv8ch]

You can also forego the baffle reenforcement and mount the oil cooler on the firewall. That location also gives you the option of a bigger oil cooler. I have a 9a with a Titan IO-370 and the 7 row cooler was not adequate in the Summer months.

I mounted my cooler on the baffle, with a lot of extra structure, and I still see cracks starting. Cooling is more than fine. I will probably re-do it more like the RV-14. If I were at the stage that @skelrad is now, I'd go with the RV-14 solution. Baffles are not designed to have that kind of weight hanging on them, which is why there is so much discussion about cracking. Mis dos centavos.

 

[Taltruda]

I agree with RV8CH.. mounting the oil cooler on the baffle is a mistake. Eventually it will crack, and either someone will have to repair it over and over, or they’ll redo it the right way and mount it on the firewall. My vote (if you’re taking votes) is to do it right the first time, and NOT mount it to the baffle.

 

[Kiwifly]

with the corner brace tube, there don't seem to be any reports of cracking, the 9 certainly doesn't need a bigger cooler, I have a shutter fitted to mine to reduce cooling.

 

[fixnflyguy]

This is on my -4, but the same dynamics apply. I used SS tubing and a fitting I made for my case halves. 400 hrs., no cracks. Either tube, or angle will do the same thing. Hardware store angle is often 6061 and should work fine. If you use tubing as I did there is a process for "smashing" tube so it doesn't crack. You need to eliminate sharp points from the vise, and a thin filler inside the squeezed area that keeps it from fully flattening..kinda hard to explain.

 

[lr172]

I agree with RV8CH.. mounting the oil cooler on the baffle is a mistake. Eventually it will crack, and either someone will have to repair it over and over, or they’ll redo it the right way and mount it on the firewall. My vote (if you’re taking votes) is to do it right the first time, and NOT mount it to the baffle.

While this is an issue with the design, I don't think this is a fair statement. I read all the posts on this subject when I built my 6 and took steps top beef up the mounting area. I am at 1450 hours on that plane now and no cracks. Sure, the design is poor as shown in plans, but can be successfully improved. The firewall mounted option is not perfect either, as shown on plans. My 10 has this design and cooling performance is lower than the other option IMHO.

 

[Jerry Fischer]

I'm putting together the baffles and planning out my oil cooler support (9A). Sounds like people have pretty good success beefing up the outer baffle corner with a piece of 1" aluminum angle, as well as supporting the inside cooler flange with a cylinder or boss mounted support that creates a triangle to the cooler.

I don't have any 1" structural aluminum angle on hand. For this use, would the garden variety angle from the big box store be okay, or should I put everything aside until I can order a chunk of structural angle?

3/4 x 3/4 from scrap and I added nut plates and never had any more baffle cracks on the RV7
PS use the inside radiused angle to prevent stress.

 

[Ironflight]

While this is an issue with the design, I don't think this is a fair statement. I read all the posts on this subject when I built my 6 and took steps top beef up the mounting area. I am at 1450 hours on that plane now and no cracks. Sure, the design is poor as shown in plans, but can be successfully improved. The firewall mounted option is not perfect either, as shown on plans. My 10 has this design and cooling performance is lower than the other option IMHO.

You can easily “do it right” either way. We have four airplanes with O-360’s and Van’s baffle kits - three have the coolers mounted to the baffles,a Dina one has it on teh firewall. The one on the firewall works great, and there was plenty of room for it (non-RV, our big Tundra). the RV’s are all much tighter to the firewall, so its more difficult to fit the cooler on teh firewall. Build the baffles right and you won’t have a problem.

 

[johnbright]

Many threads on this, here's one:

https://vansairforce.net/threads/oil-cooler-bracket-separated.73707

I like post 28 in that thread YMMV. I resurrected post 28's photos, ref post 38.

 

[Taltruda]

While this is an issue with the design, I don't think this is a fair statement. I read all the posts on this subject when I built my 6 and took steps top beef up the mounting area. I am at 1450 hours on that plane now and no cracks. Sure, the design is poor as shown in plans, but can be successfully improved. The firewall mounted option is not perfect either, as shown on plans. My 10 has this design and cooling performance is lower than the other option IMHO.

Maybe my statement was a little unfair, yes, you could brace and support the baffle mounted cooler to make it last, thick angles, a middle support rod, ect.. but after all those modifications to prevent it from cracking, sometimes they still do. I’ve never seen a firewall mounted cooler cause cracks on the baffles. And with the larger Scatt or Sceet hoses, they cool just fine.