Note from a Sick Puppy

Cheap tools are no bargain... but about half of my bucking bars and bumping
dollys started out as the head of a large ball peen hammer... or small drilling
sledge. (You can pour the hole full of lead for added mass.)

Most homebuilders aren't aware of the fact that the basic bucking bars are
MEANT to be modified. You'd start with a standard #149 (or whatever), mark the
part you wanted cut away, fill out the ticket and send it over to the machinist
to be modified. It would come back, cut to the required shape with the edges
all smoothed up and the face polished. Then it would go onto the rack
associated with that particular assembly jig, allowing you to reach in through
the access panel, up through the lightening hole and set a particular row of
rivets whilst hanging upside down by your toes.

Funniest thing in the world is to see some RV assembler struggling to set a
rivet with an unmodified 142. But even funnier is the look on their face when
you suggest cutting off that troublesome edge or machining a groove in the face
to clear the adjacent rivet.

A buck is a portable anvil. It's supposed to MATCH the work. One glance at
rack of the things should give you a hint that they can come in ANY size &
shape. While the original fabrication may have used half a dozen modified
bucks, you can't believe how crazy things get when you're talking repair work.
Coming up with a buck that works, without having to dismantle the whole damn
wing, makes string theory sound simple.

Nowadays, the hardest part of making up a buck is finding a suitable lump of
steel without having to take out a second mortage. For me, those Harbor
Freight hammers and sledges have been like money from home :-)

-R.S.Hoover

In Veeduber wrote:

Nowadays, the hardest part of making up a buck is finding a suitable
lump of steel without having to take out a second mortage. For me,
those Harbor Freight hammers and sledges have been like money from
home :-)

I've been blessed by having a small quantity of 3/4" steel plate and
other scrap to work with. So far it has been used to make press brake
dies for forming fittings, some small jigs, and a few bucking bars.
Here is a picture I took of my homemade bars and the leather storage
pouches which protect the polished surfaces when not in use:

http://www.rawlinsbrothers.org/buckbars.jpg

Bar #1, from left, is made to a pattern published in the Bear-Tracks
newsletter, and is what Bob Barrows recommends for bucking "all" of the
rivets on the Bearhawk. #2 is similar to the heel/toe bars included in
riveting kits except the big end is 1-1/8 rectangular steel, and the
handle is a piece of steel pipe filled with lead to give it more heft. #
3 is something I made for bucking rivets inside wing leading edges, and #
4 was the scrap left over after cutting #3. It looked like it might be
useful at some point. These were cut out using the taiwanese bandsaw
that should be in every homebuilder's garage, with the working edges
polished down to 400 grit and buffed with emery compound on a sisal
wheel.

I probably spend too much time making tools and not enough making actual
airplane parts, but it is all part of the fun I guess. Thanks for the
tip on the el cheapo hammers as a source of material. I have another
bar in mind but haven't been able to find a suitably thick piece of
scrap steel.

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/

I probably spend too much time making tools and not enough making actual
airplane parts

-------------------------------------------------------

I've always assumed scratch-building airplanes WAS about making tools. The
airplane is simply the by-product and an inexpensive one at that.

Except for a couple of Dreadnaughts like Dave Long's Midget Mustang, the sheet
aluminum in most lightplanes only amounts to a couple hundred pounds at best.
Even purchased new it's hard to spend more than a thousand bucks for the
aluminum, assuming you buy from the distributor and not some retail outfit that
only handles aluminum as a sideline. Access to aerospace surplus sales yards
can reduce that amount to an average $2/lb, including rivets.

Different strokes an' all that.

-R.S.Hoover

From: Del Rawlins

snip


I probably spend too much time making tools and not enough making actual
airplane parts, but it is all part of the fun I guess.


Del Rawlins-

That's when you know you are doing things right. A properly made tool, fixture
or jig is supposed to make the project easier.

I can't tell you the number of times I have modified a tool for a one of
project and have later found other uses.

Dan, U.S. Air Force, retired

On 20 Mar 2004 18:21:31 GMT, (Veeduber) wrote:

Cheap tools are no bargain... but about half of my bucking bars and bumping
dollys started out as the head of a large ball peen hammer... or small drilling
sledge. (You can pour the hole full of lead for added mass.)

Most homebuilders aren't aware of the fact that the basic bucking bars are
MEANT to be modified. You'd start with a standard #149 (or whatever), mark the
part you wanted cut away, fill out the ticket and send it over to the machinist
to be modified. It would come back, cut to the required shape with the edges
all smoothed up and the face polished. Then it would go onto the rack

I never could figure out why you guys go to allt he work of polishing
the things.

A little rust, a bit of pitting, and they aren't near as likely to
slide off. I'll admit they are a bit messy to use and it does take a
bit of cleaning up afterwards. Well, that and your leather gloves
leave hand prints on everything they touch after that.

snip

Nowadays, the hardest part of making up a buck is finding a suitable lump of
steel without having to take out a second mortage. For me, those Harbor
Freight hammers and sledges have been like money from home :-)

I've found our local steel supplier has a big bin/dumpster of small
pieces of all sorts of sizes and thicknesses and it's generally free.
Course I have purchased a small fortunes worth of big pieces from him
too.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

-R.S.Hoover