HAMMER-AND-NAIL FITNESS

(Page 2 of 2)

December/January 1998
 
Article Tools
Print
Comments
RSS
Bookmark and Share

RELATED CONTENT

Cut a 3/8"-diameter steel shaft to length (6", by these plans), so that it passes 1" into one of the 24 1/2"-high pieces and protrudes 1/8" outside of the opposite 24 1/2"-high piece.

Assemble the two side frames using coach bolts, spring washers, and nuts. The two frames should be carefully aligned before drilling the holes for the lower pulley shaft. After drilling the holes, place the steel pulley shaft in position to keep the two side frames aligned. Then position the two 20"-long top pieces and drill the 3/8"-diameter holes for the top pulley shaft (use a 5"-long coach bolt for this upper shaft).

Bolt the two side frames on either side of the rear frame and install the pulleys with a suitable number of 1"-outside-diameter x 3/8"-inside-diameter packing washers, as shown on the plan view drawing. (I used six 3/64"-thick washers on each of the two pulley shafts.)

Cut two 9 1/2"-long foot rests from 2 x 4 material and screw them to wedges mounted on the 54"-long inclined pieces.

ASSEMBLING THE WEIGHT SYSTEM

Cut a 9 1/2" length of 3/8"-diameter rope and tie it to a 1 1/2"-diameter dowel. Feed the other end of the rope over the two pulleys and attach to the desired number of 5-pound and/or 10-pound weights.

Workout Math

If four 10-pound weights are used and the distance through which they are raised is 41", then the work per stroke is: 41"/12 x 40 Ibs = 137 ft-Ibs. If this work is done in 1.08 seconds (which corresponds to 120 strokes in 4 minutes, 15 seconds) the power is 137 ft-lbs/1.08 secs x 1.356 = 171.6 watts (or 0.23 hp). To calculate other powers, use the following equation: power (watts) = 0.113 x distance load is raised (inches) x total weight (lbs)/time (secs).

Page: << Previous 1 | 2 |
Bookmark and Share
RSS | Comments | E-mail | Print

Comments

Add Your Comment

Please note that there is currently a problem with the comments function and your comment may or may not post successfully. We are working to correct the problem and thank you for your patience. 

You can use this comment form to enter your personal experiences or additional information and resources that you'd like to share with Mother Earth News readers. Your helpful advice will be posted on this page.  E-mail addresses are never displayed on comments, but they are required to confirm your comments.

Line breaks and paragraphs are automatically converted — no need to use <p> or <br> tags.

New to Mother Earth News?
Sign up to share comments.
Asterisks(*) indicate required fields.
Name*
Your name appears next to your comment.

E-mail Address*
This will be your login ID.

City State Zip Code

Password*


Confirm Password*

Comments
1500 character limit (Offensive materials and/or spam will be removed, no HTML allowed)
Please Note: Your sign-up must be verified via e-mail before your comment is published.
FEATURED ARTICLES
MOST POPULAR


Subscribe Today - Pay Now & Save 66% Off the Cover Price

First Name: *
 Last Name: *
Address: *
 City: *
State/Province: *
 Zip/Postal Code:*
Country:
 Email:*
(* indicates a required item)
Canadian subs: 1 year, (includes postage & GST). Foreign subs: 1 year, . U.S. funds.
Canadian Subscribers - Click Here
Non US and Canadian Subscribers - Click Here

Lighten the Strain on the Earth and Your Budget

Mother Earth News is the guide to living — as one reader stated — “with little money and abundant happiness.” Every issue is an invaluable guide to leading a more sustainable life, covering ideas from fighting rising energy costs and protecting the environment to avoiding unnecessary spending on processed food. You’ll find tips for slashing heating bills; growing fresh, natural produce at home; and more. Mother Earth News helps you cut costs without sacrificing modern luxuries.

At Mother Earth News, we are dedicated to conserving our planet’s natural resources while helping you conserve your financial resources. That’s why we want you to save money and trees by subscribing through our Earth-Friendly automatic renewal savings plan. By paying with a credit card, you save an additional $4.95 and get 6 issues of Mother Earth News for only $10.00 (USA only).

You may also use the Bill Me option and pay $14.95 for 6 issues.