What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Wheel pants repaired/refurbished?

MacCool

Well Known Member
RV-9A...wheel pants have all taken a beating over the years from one or two bad grass fields and a couple of flat tires on landing. Stress cracks etc at some of the edges. No missing fiberglass.

We have a great body shop in the area, and because this is high-end lake country, they do a huge amount of major fiberglass repair on boats. That said...boats are not airplanes and they're a little concerned about working on airplane components. My goal would be to drop them off, have them do the fiberglass work, then repaint, and we're good to go. However, I'm wondering if I wouldn't be better off sending them off to someone with substantial experience in wheel pants repair. I can arrange the painting, but I don't really have the time to do the job myself right now.

Anyone here know of any companies, services, or experienced builders that does this kind of wheel pants restoration work?
 
My concern about using a boat out automotive place is that they probably use fiberglass mat AKA horsehair instead of actual 9 ounce fabric cloth. Most of us now use epoxy resins, although the wheel pants are probably made from polyester resin, so either one is ok IMO. Another thing is that boat/automotive shops probably don’t pay much attention to the weight of their work..
 
I’ve never found fiberglass repair to be a very time consuming task. Spend more time waiting for resin to dry than anything else.
 
Bob K. at HP Aircraft LLC (an advertiser here on VAF) would probably be willing to do the repair, charging for time and materials.

Bob won't do the paint though. You will get it back with grey vinyl ester primer on the repair areas - or perhaps over the whole thing. Would be basically ready for paint.

You can contact him at HPaircraft.com
 
My concern about using a boat out automotive place is that they probably use fiberglass mat AKA horsehair instead of actual 9 ounce fabric cloth. Most of us now use epoxy resins, although the wheel pants are probably made from polyester resin, so either one is ok IMO. Another thing is that boat/automotive shops probably don’t pay much attention to the weight of their work..

Yeah, they'd be my second-to-last resort (last resort would be me doing it). I'm hoping to find some place a little more aviation-specific.
 
If you have a warm workshop, you should give it a go yourself. Have a look at DanH's posts on doing fiberglass, get the stuff needed, and practice a bit. It's quite satisfying if you are patient, have the right materials, and the right workspace. If in the end it turns out horrible, then give it to someone else to fix - they can just sand away whatever you did if needed.
 
I would have no issues using a boat shop to repair and paint wheel pants. I am sure they have WAY more F/G experience than any aircraft shop. It is not a structural part, so no need for an airframe specialist. In order to assist with further repairs, I would ask the shop to use epoxy instead of polyester resin for the repairs. I am certain they have experience with that for repairs. I believe the original pants were polyester and somewhere along the way they switched to epoxy. Polyester resin wont adhere well to epoxy.

Larry
 
Last edited:
*sigh*...long waiting list for this kind of fiberglass repair. Looks like I may have to do it myself :mad: .


My wheel pants are painted with automotive paint. What's your favorite method of paint stripping from fiberglass? Chemical vs soda blasting? If chemical, what's your favorite stripper.
 
Sanding

Ive never used chemicals on fiberglass. Repair, sand smooth, shoot epoxy primer, paint with 2k enamel of one color.

If the few ounces of old color bothers you, sand it off. FG is porous to a degree, not sure id want a chemicals on them, scared id not get it all off . I did this to all my FG parts last year. Cowl, pants, VS trim etc. All looked like new.
 
*sigh*...long waiting list for this kind of fiberglass repair. Looks like I may have to do it myself :mad: .


My wheel pants are painted with automotive paint. What's your favorite method of paint stripping from fiberglass? Chemical vs soda blasting? If chemical, what's your favorite stripper.

I wouldn't remove the paint just hit it with a DA to knock it down some and all the way to F/G where paint is loose or chipped. Aircraft stripper would work, but not sure what it will do to the F/G. Soda blasting is a bad idea, as it chemically interferes with the bonding of some / many epoxy primers. Sand blasting is OK.

Larry
 
Last edited:
Repairing wheel pants really isn’t that hard, and doesn’t take that long - you just have to have a few materials and be willing to make a little bit of a mess. You can leave the old paint on there, and my recommendation is that when you design a paint scheme, make the bottom half of the wheel pants a regular Krylon or Rustoleum color so that they are easy to repaint after repair.

I covered wheel pant repair in Kitplanes a few years back:

https://www.kitplanes.com/easy-wheelpant-repair/
 
The chemical stripper is very strong, it will eat away from the epoxy underneath the paint. I used the paint stripper on my 2K epoxy primed metal part and the epoxy coating lifted off the surface in about 5 minutes after the application of the chemical.
 
*sigh*...long waiting list for this kind of fiberglass repair. Looks like I may have to do it myself :mad: .


My wheel pants are painted with automotive paint. What's your favorite method of paint stripping from fiberglass? Chemical vs soda blasting? If chemical, what's your favorite stripper.

Many won’t use stripper on fiberglass. Bad things can happen. Sanding is a common approach.
 
You can always just buy a new set from Van’s. If they are really bad, this might also be the cheaper solution.

Carl
 
Great advice, guys. I really appreciate you taking the time to help. Not sure what I'm going to do yet. My gear leg fairings are mounted very solidly, so at least I can fly the plane while they're under repair, after the condition inspection is done.
 
W&C Aircraft in Boone Ia. I’m there now building a 9A. They are a builder assist shop. Very knowledgeable
 
As it turns out (discovered while stripping the finish) it looks like these wheel pants were gel coated rather than painted. When I finish the fiberglass repair, should I have them painted or re-gel coated?
 

Attachments

  • EE13A434-886F-4DBD-A4E9-EF8AED75CA80.jpeg
    EE13A434-886F-4DBD-A4E9-EF8AED75CA80.jpeg
    250.4 KB · Views: 163
Epoxy prime

I would not gelcoat. Difficult for future repairs. Sand/wet sand the finish 220.
Do the various structural repairs with epoxy and FB cloth. Personally I like West System. Sand the repair then coat with a fairing mix of 410 filler (easiest to sand) when fair, then Prime with a high build epoxy primer. Primer will wet sand buttery smooth. Re fair and re-prime if needed. Personally i would color match and finish spray with Imron that you can purchase at a local auto paint store. Imron is very durable, although toxic to spray. Another option is prep them smooth and drop them off at an auto body shop and have them painted with the Imron. They should be set up to deal with the toxicity issues.

You may enjoy the challenge of DIY. PM me if you want to give me a call. I can guide you through this. Its easier than you think.
 
Last edited:
I would not gelcoat. Difficult for future repairs. Sand/wet sand the finish 220.
Do the various structural repairs with epoxy and FB cloth. Personally I like West System. Sand the repair then coat with a fairing mix of 410 filler (easiest to sand) when fair, then Prime with a high build epoxy primer. Primer will wet sand buttery smooth. Re fair and re-prime if needed. Personally i would color match and finish spray with Imron that you can purchase at a local auto paint store. Imron is very durable, although toxic to spray. Another option is prep them smooth and drop them off at an auto body shop and have them painted with the Imron. They should be set up to deal with the toxicity issues.

You may enjoy the challenge of DIY. PM me if you want to give me a call. I can guide you through this. Its easier than you think.
Thanks, nice overview. I have experience with fiberglass repair (boats - I just finished fixing up my kids' old Whaler)...I just dislike doing it (tired of sanding). This is a little different since it's at the mounting holes and is at least semi-structural. I have some West 105 and hardener back in the shop. I was hoping to do this in the hangar, but still winter here, apparently.

My plan is to clean, and then reinforce the cracks at the mounting holes by laying some 6 oz fiberglass on the inside (I'm afraid 9oz will be too thick and interfere with re-mounting). I'll probably drip some thin CA into the cracks. Do you think I can then just fair the outside with some microballoons, or would it be better to open the cracks a little from the outside with a dremel and fill with some flox?

Yeah, then I'll take it to the body shop for prep and paint. I was hoping that the advice would be not to re-gelcoat.

I was hoping to get this done before the start of the upper midwest fly-in season, but I guess I'll have to accept flying without pants for awhile :) .
 
Last edited:
Damaged area

If you sand down the damaged area to a recess and and create a feathered edge, you can apply the cloth with multiple layers. This will be a better way and the pro way of fixing this. After you sand the cloth it wont be proud of the surface. Allow for a 1/16- 1/32 or so of low area that will be filled with the 410 fairing compound. It will finish out smooth. Flox is to hard to sand and will make a mess and i don’t recommend it on the surface at all unless it remains lower than the surrounding areas. You can then finish off with the easy sanding 410. Much better and stronger fix. Putting some cloth on the inside as well is not a bad reinforcing method. I used carbon fiber as a reinforcement in this area. The key is to create a feathered edge for the new cloth to bond to.
Sanding with the right tools takes minutes
 
Last edited:
Cracks?

Thanks, nice overview. I have experience with fiberglass repair (boats - I just finished fixing up my kids' old Whaler)...I just dislike doing it (tired of sanding). This is a little different since it's at the mounting holes and is at least semi-structural. I have some West 105 and hardener back in the shop. I was hoping to do this in the hangar, but still winter here, apparently.

My plan is to clean, and then reinforce the cracks at the mounting holes by laying some 6 oz fiberglass on the inside (I'm afraid 9oz will be too thick and interfere with re-mounting). I'll probably drip some thin CA into the cracks. Do you think I can then just fair the outside with some microballoons, or would it be better to open the cracks a little from the outside with a dremel and fill with some flox?

Yeah, then I'll take it to the body shop for prep and paint. I was hoping that the advice would be not to re-gelcoat.
.

Cracks? Hairline cracks, like on the surface? If that is the case, they are likely down through the gelcoat. Gelcoat is rather brittle and not so strong. If the crack is not completely eliminated, it will reappear under your new money, errrr . . . .paint.

On one hand you could take the parts to Midwest Refinishing in Hibbing. Cirrus restorers, painters and outstanding glass knowledge.

But if you are going to do the work , definitely grind down through the gelcoat to do your repairs. Pants are typically thick enough to do one side and lay some cloth. 6oz is good, West is good. I had my gear leg fairings overly restrained and cracked one. They are very thin, I sanded one side with a 1.5-2" arc applied one 6 oz layer, allowed to set, then did the same inside but ground to the patch on the opposite side to be sure the fracture was all gone. Sanded both sides to level and even. I like to do one side at a time to stabilize the piece.

Cracks, recently had an event on my tip, and flexure cause a sunburst of cracks in the gel coat. I first identified all the cracks with a bit of black ink from a printer. Swipe on, wipe off, clean with iso-alcohol. Then using a tulip 1/8" OD grooved the cracks to the glass, not below, and filled the them with a mix of 105, chopped glass fibers, and cabosil. Mixed a lightened slurry still flowing then stiffened with a touch of cab. Mixing only filler to a stiff consistency will not cure well.

If a "crack" has whitened the glass on the inside, then definitely do a two sided job to completely replace the failed area.

I learned all this from DanH , others and breaking stuff.

If you are careful, a 90 deg die grinder with a 2" green roloc sanding disc can do all but the finish grinding.
 
If you sand down the damaged area to a recess and and create a feathered edge, you can apply the cloth with multiple layers. This will be a better way and the pro way of fixing this. After you sand the cloth it wont be proud off the surface. Allow for a 1/16- 1/32 or so of low area that will be filled with the 410 fairing compound. It will finish out smooth. Flox is to hard to sand and will make a mess and i don’t recommend it on the surface at all unless it remains lower than the surrounding areas. You can then finish off with the easy sanding 410. Much better and stronger fix. Putting some cloth on the inside as well is not a bad reinforcing method. I used carbon fiber as a reinforcement in this area. The key is to create a feathered edge for the new cloth to bond to.
Sanding with the right tools takes minutes

OK, thanks. Do you think that 6 oz fiberglass cloth is too heavy for layering on the outside?

Guess I'll get some carbon fiber to re-inforce the mounting area. I like that idea.
 
6 oz

I think you should be fine with the 6 oz. Don't be afraid to sand away the damaged areas. The lower the recess in this case the better as you will be able to build up more new cloth that will bond to the feathered edge. Just be sure to keep the new repaired area lower to accept the fairing filler. You should be able to hit it with primer and not see the repair.
 
On one hand you could take the parts to Midwest Refinishing in Hibbing. Cirrus restorers, painters and outstanding glass knowledge.

Intriguing option..thanks. I just sent them a request for a quote. The Hibbing airport is only about a 30 minute flight from here.
 
In my glider days, doing fiberglass repairs, we used to painstakingly and accurately sand scarf-lines by hand to prepare for a wet lay-up patch. It took many hours of filing, sanding and measuring spread across multiple days.

Then we watched a professional do it. He ground-out his scarf line with a 4-inch angle grinder. It took him about a minute and a half.

Wheel pants are a non-structural part, and a good coat of paint covers up all manner of sins.

My approach would be to use a barrel sander tool on a Dremel to grind back the paint and enough glass to make a scarf line for a patch. Then do the lay-up, use the dremel to cut/sand back the rough edges, apply cotton flock + epoxy filler, sand 'til it's smooth, and paint. It's a wheel pant, it doesn't need to be as strong as a main spar (and no matter how strong you make it, you know it's going to get chipped and cracked again anyway)

I wouldn't bother with gelcoat. As others have observed, it's brittle and prone to cracking (older fiberglass gliders used gelcoat to visibly indicate damage, where the glass structure would bounce back into its regular shape but the surface finish would be shattered)

Making it strong enough and visually attractive can be mostly achieved rapidly with power tools, with minimal wet sanding by hand. And if you get it wrong, it's not hard to grind it back and start again anyway :)

- mark
 
Well, Midwest didn't return my calls or emails so I guess I'm on my own :( .

I opted to buy a 2" orbital sander from Harbor Freight and found that a prep-stripping disc works pretty well in getting me through the gelcoat down to the substrate. I'm doing what Airguard suggested...going to lay down a couple of layers of 6 oz fiberglass on the outside. This is tip of the nose gear wheel pant. It has a couple of lower front cracks and a inside dirt clod gouge.

Suggestions?


.
 

Attachments

  • nose wheel1.jpg
    nose wheel1.jpg
    236.3 KB · Views: 73
  • nose wheel2.jpg
    nose wheel2.jpg
    286.7 KB · Views: 82
  • nose wheel 3.jpg
    nose wheel 3.jpg
    227.5 KB · Views: 87
  • nose wheel 4.jpg
    nose wheel 4.jpg
    254.1 KB · Views: 84
I might put one layer of glass on the outside, and a couple layers on the inside in the affected areas. Having only one on the outside will make blending easier.
Maybe also put a couple layers on the inside in mirror image locations that haven't yet cracked.
 
I might put one layer of glass on the outside, and a couple layers on the inside in the affected areas. Having only one on the outside will make blending easier.
Maybe also put a couple layers on the inside in mirror image locations that haven't yet cracked.

Yeah, as we discussed. I ordered some carbon fiber cloth and I plan to put a couple layers of the insides where the damage is. I’ll use probably a couple layers of fiberglass on the outside. The fiberglass of that nose gear wheel pant is pretty thin compared the main gear pants.
 
Good path!!

Well, Midwest didn't return my calls or emails so I guess I'm on my own :( .

.
Try 218-404-0314 . . . . I think that is a common number that Ross, George, or Kris will answer. It is not like them to miss a call.

In any case, you are on a good path, and if it goes badly, sand it back off and do it again.
 
Back
Top