Sonar Tow Cable Sheave Plans
Drawing package and bills of material to build your own 12 in bend diameter sheave for towing an Imagenex YellowFin side scan sonar on Rochester A240185 3/16 in armored wireline.
The finished sheave, built to these plansCheckout is being set up. Get in touch if you want a copy now.
The package includes
- 13 drawings (4 assemblies, 9 parts) as ANSI B PDFs
- BOMs with McMaster-Carr numbers for the purchased parts
- Assembly notes: press fits, torques, fit checks
- Material and finish called out on every part
To build it yourself you need
- Manual or CNC mill for the plates, anchor and retainers
- Rotary table on the mill for the wheel
- Lathe for the axle
- Arbor press for the bronze bushings
- Anodizing, in house or outside
- Or send the drawings to a machine shop
Drawings in the package
| RR-SHEAVE-10014 | Sheave assembly, 12 in bend diameter |
| RR-SHEAVE-10013 | Frame assembly, fixed |
| RR-SHEAVE-10012 | Plate assembly, side, moveable |
| RR-SHEAVE-10006 | Sheave wheel assembly |
| RR-SHEAVE-00011 | Axle, 17-4 PH |
| RR-SHEAVE-10003 | Wheel, threaded side |
| RR-SHEAVE-10004 | Wheel, non-threaded side |
| RR-SHEAVE-10005 | Wheel bushing, bronze |
| RR-SHEAVE-10007 | Side plate, moveable |
| RR-SHEAVE-10008 | Side plate, fixed |
| RR-SHEAVE-10009 | Cable retainer, acetal |
| RR-SHEAVE-10010 | Top anchor |
| RR-SHEAVE-10015 | Axle bushing, bronze |
The finished sheave
| Cable | 3/16 in wireline, Rochester A240185 or equal |
|---|---|
| Bend diameter | Ø12.07 in pitch |
| Working load | 1,250 lb at the hook, including dynamic loads |
| Overall size | 13.50 W x 19.25 H x 3.33 D in |
| Weight | 11.6 lb |
| Wheel | Ø13.50 in, 6061-T6, on SAE 841 bronze bushings |
| Axle | 17-4 PH stainless |
| Mount | 5/8-11 rotating eyebolt, swivels 360° |
| Fleet angle | 2° max |
Max line tension at 1,250 lb hook load
| Wrap angle | 180° | 120° | 90° | 60° |
|---|---|---|---|---|
| Line tension, lbf | 625 | 722 | 884 | 1,250 |
Hook load = 2 x line tension x sin(wrap / 2). Stay within the cable's own working limit too.
What the drawings look like
The top assembly drawing, watermarked. Every part drawing has the same title block, tolerances, material, finish and notes.
🔍 Click to enlargeBuilt and used on the boat
Photos from building the sheave in these plans. The full build story is on the cable sheave project page.
Questions
What do I get?
One ZIP file: the 13 drawings as PDFs (ANSI B size, 11 x 17), the bills of material with McMaster-Carr part numbers for the purchased parts, the product data sheet and the assembly notes.
How do I get the files?
Right after you pay, the checkout shows a download button, and the same link is emailed to you with your receipt. Lost the email? Get in touch and I will resend it.
Do I need CAD?
No. Every part is fully dimensioned on its drawing, so a machinist can work straight from the PDFs.
Can a machine shop make the parts for me?
Yes. You may give a shop the drawings for the parts they are making for your sheave. See the plans license.
How was the 1,250 lb rating worked out?
From an engineering analysis of every part in the load path, with a design factor of 3 on yield (ASME BTH-1, Category B) and 4 on breaking strength (ASME B30.26). It applies to a sheave built with the materials and hardware on the drawings.
Can I buy a finished sheave?
Yes. Contact me for price and lead time.
Refunds?
The plans are a digital download, so sales are final. If a file is damaged or missing, I will send a working copy.
Checkout is being set up. Get in touch if you want a copy now.
Plans are licensed to the buyer to build sheaves for their own use. A machine shop may use the drawings to make parts for the buyer. No resale of the drawings. See the plans license. YellowFin is a trademark of Imagenex Technology Corp. Not affiliated.