prop hub--how tight

[alwaysoar]

There's no way to measure this with a torque wrench that I can figure out, but is there some guideline about how tight the prop hub should be? Obviously, it should be TIGHT! But using an X for a tool, if a 150 point weakling twists it, then.....?

Thanks,

Ed @BTV VT
TF 527

[alwaysoar]

Re: prop hub--how tight

ps. Has anyone got a "key, prop hub" p/n 500400 that's in perfect shape they could over-night to me?

Thanks, ED

[Victor Gisclair]

Re: prop hub--how tight

I have one for a cont. 65. I was'nt planning on getting rid of it but if you need one PM me and we can come up with someting.
Vic
N95110
N8839D

[high time cub]

Re: prop hub--how tight

Hi alwaysoar, The March 2005 issue of Vintage Aircraft covers removal and installation of hubs in detail. There's info on how to make special tools including a modified 1-1/16 inch-1/2 inch drive socket to use with your torque wrench. The hub is torqued 200 to 225 foot pounds. If interested, PM me and I can scan it.

[alwaysoar]

Re: prop hub--how tight

I tried to find the article you mentioned online, but Vintage Aircraft only puts features online. I would really appreciate the article--I've been intalling my hub incorrectly all this time, I'm afraid--certainly not to 200 foot pounds.
Thanks for the offer.

Ed

[Robert Lees]

Re: prop hub--how tight

no way to measure this with a torque wrench

There is...but the torque wrench is about 5 foot long, with a 3/4" drive. You need a big person on the prop hanging on to counter the torque. Yes, the prop needs to be on only to counter the torque!

I made a tool to deliver the torque from the torque wrench (photos on https://www.Taylorcraft.org.uk/Other...tionPhotos.htm about half way down the page).

[alwaysoar]

Re: prop hub--how tight

Thanks Rob, Now where am I going to get such a tool AND a torque wrench that will go to 200 foot pounds?!

[flyguy]

Re: prop hub--how tight

Use a breaker bar with a pipe over it to equal 4 foot total and pull with 50 lbs of force. Find a 50 lb. barbell and set it on the end of the bar, if it moves, it doesn't have 50 lbs. on it yet. We've all been making tools for years. It helps to know a competent machinist. Do the socket thing. I bought a 3/4 inch bar for putting the front struts on a 3rd generation Pontiac Firebird, and put a pipe over it. At my weight I practically had to do a push up on it to get enough torque. Is the spec. "wet" or dry? It makes a BIG difference.
Darryl

[alwaysoar]

Re: prop hub--how tight

Good idea--That solves the, where to I find a torque wrench problem. Thanks, Ed @BTV VT

[zero.one.victor]

Re: prop hub--how tight

I read the prop hub installation article also. Very informative. The article has a photo of torking the prop hub nut down with a standard-size tork wrench & the specially-made socket/adapter (page 17). The article cautions against using a big breaker bar & estimating tork (by hanging on it, etc)-- besides usually getting the thing on so tight you can't get it loose later, you take a chance on unduly stressing the hub & shaft which invites cracks.
I think whatever standard size tork wrench that goes up to 200-225 ft-lbs should be used. If you don't have enough beans to tork it that much, put a short extension onto the handle area of the tork wrench. A 12 inch extension should allow 100 ft-lbs of elbow grease to be multiplied to 200 ft-lbs at the handle area of the wrench. No?

Eric

[zero.one.victor]

Re: prop hub--how tight

I just checked my Sears Craftsman tool catalog. They have a couple 1/2" drive tork wrenches that go to 250 ft lobs. One (a digital model) is $99.99, the cheaper of the two analog (?) models is $139.99. This one measures 21" long. FWIW

Eric

[Guest]

Re: prop hub--how tight

I think there is a Continental Service Bulliten that tells how to tighten the hub. Check out the Continental site. Dave.

[Guest]

Re: prop hub--how tight

I think there is a Continental Service Bulliten that tells how to tighten the hub. Check out the Continental site. Dave.

I just read an Aeronca Service Letter (#14) that gives instructions on taper shaft prop hub removal & installation. It is also called Champion Aircraft Helps & Hints #14.