Harvard canopy rubbers

Ollie · **Posted:** Mon Feb 25, 2013 1:39 pm

My rollers have been ordered, but now I need some weather strips for my new canopy transparencies.

I've heard that they are very hard to find and that nowadays folks use RTV and other products to make everything fit.

What's your take on that?

:roll:

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11319

I have no experience, but wouldn't RTV be kind of weak? I think fuel tank sealant would be stronger, but be careful you don't glue your canopy shut!

I'm curious to know the "real" answer to this.

Ollie · **Posted:** Mon Feb 25, 2013 4:02 pm

That's what the guy at Lance told my mechanic.

51fixer · **Posted:** Mon Feb 25, 2013 4:08 pm

bdk wrote:

I have no experience, but wouldn't RTV be kind of weak? I think fuel tank sealant would be stronger, but be careful you don't glue your canopy shut!

I'm curious to know the "real" answer to this.

I believe Lance has kits for the glass pane seals.
Their are some different setups as far as is it stock glass or thicker plexiglas. Is it G or Mk IV canopies with larger side panels. The individual parts of each canopy are different between the std and the G type due to the large single side or dual side glass panels used. Each type needs different types of channel or P strip.
Check prints or parts book as well as the reg manuals if you can.
Be careful riveting it back together as well as drilling it apart. The wedge segments in the corners are cast and I've seen them crack if your not careful.

Ollie · **Posted:** Mon Feb 25, 2013 4:23 pm

Lance do not have any kits in stock.

Looks like we'll have to go channel hunting.

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11319

Ollie,

You might want to start here:

http://www.steelerubber.com/

http://content.steelerubber.com/uploads ... cialty.pdf

They may have a master catalog of shapes, so you might want to fax them a sketch.

51fixer · **Posted:** Mon Feb 25, 2013 10:57 pm

Ollie wrote:

Lance do not have any kits in stock.

Looks like we'll have to go channel hunting.

Do you have the rubber shape out of the parts book? Might be a 2P or C3 or some designation like that.
If it matches up with my prints I can email you the dimensions from the print.

Old Shep · **Joined:** Thu Jun 09, 2005 5:49 pm **Posts:** 219

I'm in the midst of changing all the glass: it isn't easy! I've already cracked two of the side panels out of the five we've done so far (glass: very expense from Lance) plus the sizes of what Lance has did not quite fit one section of my canopy (Harvard II)....he did have the channel rubber as of three weeks ago and I hope he has more as I need some additional! There are other ways to put the glass in (and by the way the rounded plexiglas top pieces are much easier to install), you can work with some other kinds of rubber. Your A&P can suggest stuff. PRC works well along with some kind of rubber....If I break another glass piece I'll switch to plexiglas for the side pieces as well!

Old Shep

Jason · **Posted:** Wed Feb 27, 2013 12:56 am

The seal sections are hard to find, as mentioned previously, there are a few different profiles depending on what Texan/Harvard you have. Lance can supply the 7E32 which is correct for the windscreen on all Harvards according to EO-05-55A-3, probably Texan/SNJ too?

I was lucky enough to buy from Banaire nearly (!!) all the seal I needed for the Harvard IV I'm putting back together, but unfortunately I've now learned I need another 4 metres to finish the fixed rear enclosure & obviously now that Banaire aren't accepting orders, they can't help me out. I'm guessing they must of been getting it from somewhere & I'm trying to find out now?

I've just received a quote to extrude it, & that came to AU$500 to setup then $4-$8 a metre... so still looking.

I definately would not be using RTV to seal the transparencies. I used clear silicon to attach the cork strips to the transparencies, but then installed the transparencies & seals without any sealant.
Lots of soap & water were used to install them, and seal installation had to be done very slowly & carefully using a soft plastic 1 inch wide scraper to work around the frame & gently coax the seal into position.

The windscreen was the only exception, I used an industrial caulking compound (same as automotive windscreen sealant) in all of the grooves of the the extruded rubber seals.. this seemed to work well.

51fixer has good advice about being carefull rivetting the frames back together.... I wasn't comfortable rivetting them & ended up squeezing the rivets instead.

Jason

The Inspector · **Posted:** Wed Feb 27, 2013 11:46 am

Here's an old automotive trick to seal and waterproof the glass once installed (and it must work because Rolls Royce uses it for windshields and backlight glass) take a syringe or an infuster and squirt petroleum jelly into the gap edges of the gasket and glass, it remains forever flexible and cleans up easily just remember you don't need gallons of it, a very thin bead will spread out and seal perfectly. You can also use GO-JO type gel handcleaner and string to make the installation easier. A lanolin based hand cream will sometimes revive older, dried seals. :wink:

RobC · **Posted:** Mon Mar 04, 2013 11:00 pm

For the windshield, I used a product called 3M Strip-calk #08578, which I got from A/C Spruce. It is far superior to RTV. It will not peel and it is made for windshields.

For the rear Harvard (or in my case, Yale) hood, there is an extrusion in the A/C Spruce catalog, part # 05-00952. It appears to fit correctly, 3/8 OD, 3/16 ID and 1/2 inch depth. I have not tried it yet, but cannot guess why it would not work. It does not have the bead that Jason was looking for, but I don't know what that bead does. Anyone out there tried this extrusion?

Now a question: there was some discussion awhile back re: the rear hood molded pieces. I was not sure from the discussion whether you guys went to a T-6 F style bubble, or actually got the stock molded pieces. If the latter, can you tell where you got it from?

Thanks.

Ollie · **Posted:** Tue Mar 05, 2013 12:44 pm

Thanks for the tip, I'll check it out.

We went for the bubble hood, but where I got it they also had the individual panels.

http://www.aircraftwindshield.com

Ask for Jesica.

Ollie · **Posted:** Wed Mar 13, 2013 10:59 am

We found rubber extrusions here: http://www.spaenaur.ca

Should all 6 side glass windows be of the same thickness? The pilot's are thicker than the rest...

:roll:

bdk · **Joined:** Sun May 02, 2004 1:16 am **Posts:** 11319

Do you have a part number to share from their catalog?

Ollie · **Posted:** Wed Mar 13, 2013 3:21 pm

As soon as I run back to the hangar, I'll post them up and I'll have some pictures to show you how it all fits.

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