Cowl bumps

[senior]

Does anyone know of availability of cowl bumps like the ones in 3rd post down only in aluminum??
From looking at them they are as nice a little item as I can find to cover my plug holes only they are in plastic...I would prefer aluminum.

http://www.joea.com/phpBB2/viewtopic.php?f=15&t=3501&hilit=bumps

[M Jones]

Re: Cowl bumps

Maybe not as nice looking, but try these:

http://store.wagaero.com/product_info.php?products_id=8075

You would want to call and ask if they're aluminum because that's not specified. I believe they are because mine came from WagAero, but it has been a few years so they may have changed.

[mikerice]

Re: Cowl bumps

We have nice long teardrop shaped in aluminum, but they were there when we bought the BC12D. I think they might be from Univair. Not Tcraft stock items though.

[M Towsley]

Re: Cowl bumps

My first BC-12 had small cutouts above the plug leads and then someone made a couple of very small bumps that were riveted in. Much, much cleaner and nicer looking than the store-bought bumps.

[senior]

Re: Cowl bumps

We have nice long teardrop shaped in aluminum, but they were there when we bought the BC12D. I think they might be from Univair. Not Tcraft stock items though.

I tried every word or compilation of phraes I could think of on their search engine & came up with nothing.
I think I'll try the PA-11 style you pointed out since the plastic ones seem to be really odd sizes to cover the plugs!

The plastic offerings are
1. 1-1/4 deep x 3" W x 5-3/4 L
or
2. 1/2" deep x 1-3/4 W x 4-1/2 L


As a side note to those interested, the short REM-37BY plug still require bumps in all positions but right rear.
Not sure how the bird would look with two bumps one side...one bump the other

[flyguy]

Re: Cowl bumps

Univair has a longer one that handles both plugs. It is listed for Ercoupe. My old catalog page 29, P/N 40428. Online, haven't checked. Aluminium.
DC

Just looked them up online. Holy Moley Batman! $77 each.

Time to pound some metal.

[mikerice]

Re: Cowl bumps

UNIVAIR PART Catalog:

Part Number Product Name Price
415-40428 ERCOUPE SPARKPLUG FAIRING $77.81
Displaying 1 to 1 (of 1 products) Result Pages: 1

Those are the ones on our plane- I would WAG at 12-14" long. Very unobtrusive visually. I added a foam plug at the baffle to keep air from flowing thru the fairing to the rear engine compartment- was worth a noticeable temp drop on hot days...

[Hank Jarrett]

Re: Cowl bumps

Years ago I saw a friend make a tear drop blister by carefully cutting an airfoil hole through a steel plate. He clamped a piece of dead soft aluminum between the holed plate and a solid one with a threaded hole in it and proceeded to pump grease between the plates through the hole. The aluminum stretched up into the airfoil shape hole and made the most perfect blister you can imagine! He even cleaned the grease out of the blister and loaded it back into the grease pump for re-use.
I know it wasn't as easy as he made it look. He knew exactly how much to radius the trailing edge of the hole, the edges of the hole in the plate and Lord knows where he got the grease pump to form it, but it was sure pretty and each one came out exactly the same.
Hank

Imagine how the first one came out when the high pressure grease split the aluminum and sprayed it all over the room!

[flyguy]

Re: Cowl bumps

Way before I got distracted by my front tank problem I was thinking: modeling clay male form (easy), plaster female mold from that, (also easy), and then carbon fiber layed up inside. OR: fiberglass if one wished. Install with a rubber-like flexible adhesive plus maybe two minature safety bolts.
DC

[barnstmr]

Re: Cowl bumps

Personally, I dislike the thought of changing the cowl appearance on a Taylorcraft. I know that many do this. It is more effort and parts are more scarce, but I just installed ercoupe style cups... no bumps required. See thread here.

[waltermrich]

Re: Cowl bumps

Do not feel bad about sending back your harness, I bought a harness from Arn Air about 3 year ago but failed to ask how much he would charge for the harness , it was nearly $300 . I sent it back to him and he gave me a refund, I bought one out of the Spruce cataloge for $165 plus shipping , which is great. I will say he does good work on Magnetos.

[flyguy]

Re: Cowl bumps

Just seeing the picture of the Cups I had a totally subversive thought. Wonder if a plug adapter and resistive automotive plugs would work with them. I have cups now, but my Eisemann on the top is really noisy. Bottom with shieldeds is very quiet. I know the resistor damps the leading edge of the spark where the RF energy is. Probably could not work out a fit.
Ah well. I might check.
DC

[barnstmr]

Re: Cowl bumps

Are your P-leads also shielded?