VansAirForceForums  
Home > VansAirForceForums

-POSTING RULES
-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.

  #1  
Old 05-12-2022, 11:31 AM
Radioflyer Radioflyer is offline
 
Join Date: Nov 2009
Location: Boston
Posts: 225
Default Carbon Sumps

Just out of curiosity, any experience replacing the standard engine oil sump w one made from a carbon layup? The main interest would be to save weight and implement cold air induction. Some weight savings and other benefits could be gained by making the sump a smaller volume than the standard 8 qt or so capacity. Any RV's flying w carbon sumps?
Reply With Quote
  #2  
Old 05-12-2022, 11:51 AM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 6,669
Default

Ask SAP (Superior Air Parts) how that worked out for them
__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 2000+ hrs, New Titan IO-370, Bendix Mags, MTV-9 prop
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154
Reply With Quote
  #3  
Old 05-12-2022, 11:59 AM
Freemasm Freemasm is offline
 
Join Date: Nov 2017
Location: Orlando
Posts: 730
Default

Quote:
Originally Posted by Walt View Post
Ask SAP (Superior Air Parts) how that worked out for them
Weren't those Magnesium? Been too long.

Doesn't matter. Designing for the nominal case, no problem.

As for the off-nominal? One good backfire or over-prime condition/gas in the inlet for whatever reason and the experiment is over. Save weight elsewhere.
Reply With Quote
  #4  
Old 05-12-2022, 12:53 PM
David Paule David Paule is offline
 
Join Date: Dec 2009
Location: Boulder, CO
Posts: 5,300
Default

Carbon can be very thermally conductive. I've had clients use it specifically for that attribute, as a heat conductor. If you design such a thing, it's something to consider. Its thermal deformation, though, is zero to slightly negative, so the sump-case joint will be affected by that, another design issue.

Magnesium is nearly the same density (it's slightly higher) so that might be a better material.

Dave
Reply With Quote
  #5  
Old 05-13-2022, 06:50 AM
Southern Pete Southern Pete is offline
 
Join Date: Jul 2015
Location: England
Posts: 171
Default

Quote:
Originally Posted by Freemasm View Post
Weren't those Magnesium?
Ryton, an "engineering" plastic. Couldn't cope with the expansion forces involved in a back-fire. Carbon should be much better able to withstand those forces as the fibres carry the loads, but there are many other issues. A few years back Kitplanes carried a report on a carbon sump - took quite a bit of development work as I recall.
Reply With Quote
  #6  
Old 05-13-2022, 08:27 AM
rocketbob's Avatar
rocketbob rocketbob is offline
 
Join Date: Jun 2006
Location: 8I3
Posts: 3,835
Default

I still have one of these sumps for another project and have had plans to reinforce the intake with carbon and possibly add a pop off valve.
__________________

Please don't PM me! Email only!

Bob Japundza CFII A&PIA
N9187P PA-24-260B Comanche, flying
N678X F1 Rocket, under const.
N244BJ RV-6 "victim of SNF tornado" 1200+ hrs, rebuilding
N8155F C150 flying
N7925P PA-24-250 Comanche, restoring
Not a thing I own is stock.
Reply With Quote
  #7  
Old 05-13-2022, 09:42 AM
hgerhardt's Avatar
hgerhardt hgerhardt is offline
 
Join Date: Oct 2006
Location: torrance, ca
Posts: 799
Default

Quote:
Originally Posted by rocketbob View Post
I still have one of these sumps for another project and have had plans to reinforce the intake with carbon and possibly add a pop off valve.
I designed and built a carbon fiber intake for my Pontiac GTO in the 90's. It has a 440 cu in plenum with a 3" dia blowoff valve in the bottom. A few times that has come in handy with backfires which make a pretty sizable BOOM and then smoke from the hood edge gaps as it dissipates.

Problem with an airplane application is the blowoff valve needs to be on the bottom most likely, which is where the fuel would puddle if someone hamfistedly overprimes the engine. A backfire would spray all that burning fuel into the lower cowl with probably bad consequences. I suppose you could connect a tube to the blowoff valve to duct the flaming mixture out the cowl outlet, but by then the assembly is so heavy that you've defeated the original purpose of having a composite manifold.

Click image for larger version

Name:	roar5.jpg
Views:	47
Size:	114.4 KB
ID:	25778 Click image for larger version

Name:	roar4.jpg
Views:	55
Size:	81.7 KB
ID:	25779
Reply With Quote
  #8  
Old 05-13-2022, 09:26 PM
Taltruda Taltruda is offline
 
Join Date: Oct 2017
Location: Las Vegas, NV
Posts: 1,188
Default

Wow that’s a work of art! All carbon? How light was it? Seriously talented…
__________________
Tom
Las Vegas
RV-4 flying…
RV-8 empenage finished 10-2020

Wings Started.. 11-2020
Reply With Quote
  #9  
Old 05-13-2022, 10:56 PM
hgerhardt's Avatar
hgerhardt hgerhardt is offline
 
Join Date: Oct 2006
Location: torrance, ca
Posts: 799
Default

Quote:
Originally Posted by Taltruda View Post
Wow that’s a work of art! All carbon? How light was it? Seriously talented…
Thanks! It's been 25 years since I built that and at least 10 years since it's been off the engine, but it's around 10 lbs. It's not entirely carbon; it has 1/2" thick aluminum rails which bolt to the heads with the carbon bonded on top of those, and there's an aluminum ring embedded in the carbon to provide threaded holes to attach the throttle body (which I also made from billet 6061-T6 based on Chevy LT1 geometry). And the aluminum injector bosses bonded in.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 07:18 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.