- Posted by andy_c (A) on August 22, 2004 at 15:36:22
Hi all,I spent most of the day yesterday building interconnects for my new system using Belden 89259 and Canare RCAP-C4F RCA connectors. I thought I'd share my experiences in the hope that it might help anyone else considering going the same route. There are a number of helpful web sites for cable construction with the Canare crimp-type connectors, but none that I know of that specifically deal with the Belden 89259 cable. One excellent article on DIY cable construction using Canare connectors can be found at Chris White's site at http://white.hometheatertalk.com/. Click on "DIY A/V Cables". Chris used Canare cable in his examples.
There were two major issues to consider before ordering parts.
1) Find the correct Canare part number for use with Belden 89259.
2) Avoid the use of the very expensive Canare crimp tool and die.For item 1, I looked up all the relevant dimensions of Belden 89259 in the Belden catalog, which can be downloaded in PDF form from their web site. You should download this as well as the Canare PDF catalog. The key items are the outer diameter of the 89259 center conductor (.030 in.) and the nominal core OD (.135 in, also called the insulator OD). This is the dielectric OD, not the outer insulator OD (which is covered by the "Nominal OD" spec). To figure out the part number, I first figured out the pin and sleeve part numbers separately, then found the connector part number that uses that combination of pin and sleeve. Look at the Canare LV-77s center conductor spec in their catalog. It's .031 diameter, extremely close to our desired .030 value. It uses the RCAP-C77 connector, which uses the B11016D pin. So now we have our pin part number, B11016D. The insulator (core) OD of the Belden 89259 is .135 in. The closest Canare cable to this is the LV-61S at 0.142. It uses the RCAP-C4A connector, which uses the crimp sleeve BN7015A. This is the sleeve part number. So we want the Canare connector that uses pin B11016D and sleeve BN7015A. That's the Canare RCAP-C4F. I ordered these and they fit like they were made for the cable.
For item 2, there' s been much discussion in various groups about how to avoid the expensive Canare tool and die. I found out that several users have successfully used the Paladin 8000 crimping tool with the Paladin 2649 die. See the thread http://hometheatertalk.com/httalk/viewtopic.php?t=5996 for more info. Mittie Dragosljvich recommended increasing the crimping pressure on this tool by two notches, which is what I did. This tool used to be available for $22 from here: http://store.yahoo.com/technicalconnectionsinc/80secrfr.html , but these were some oddball Sprint-branded tools of which there were a limited quantity. I paid $40 for mine from the same place, but it was a true Paladin retail-packaged tool. That's still a lot cheaper than the Canare tool. I ended up using this tool with the 2649 die, and everything worked just fine.
Other items you'll need: You'll need a good coax stripper. I used the Canare TS-100E from Markertek.com http://www.markertek.com/SearchProduct.asp?item=TS100E&off=68 (cost: $67.23). This device doesn't have a standard setup for the Belden 89259, so you'll need to adjust the blade heights to make it work. I'll have more to say about this later. Have a look at Chris White's site for pictures of what the cable should look like after stripping. You should also get yourself a good cable cutter. Canare recommends using as clean a cut as possible, perpendicular to the direction of the cable with a minimum of cable "squishing". A cable cutter makes this easy. I took Chris White's advice and used the one from Parts Express - http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=360-622. Part number is 360-622. This cheap-looking tool does a great job, going through the rather stiff 89259 like butter, wich a clean, square cut. I looked for a similar tool at my local Lowe's, but that one was about $18. So you come out ahead with the PartsExpress tool, even when shipping is considered. Finally, the Canare connectors are not color-coded for left and right. You'll likely want some colored heat shrink tubing to mark your cables. PartsExpress has this. I mistakenly ordered the 6 mm stuff. It was big enough to fit over the cable, but not big enough to fit over the crimp sleeve. Bummer! Don't make the same mistake I did. Get the 12 mm stuff. They state that the 3-to-1 colored tubing can be shrunk with a hair dryer. I bought a heat gun, as I plan on using it for some other DIY electronics projects as well. If what they say is right (and I have no reason to believe that it isn't), a heat gun isn't necessary.
The other item needed of course is the cable itself. I got this at Anixter. It seemed rather pricy at $1.50 per foot for a 100 foot roll, but every other place I looked at (not a lot of places) was more expensive. If you find a good place that has it cheaper, please post!
So what was the experience like? Well, by far the hardest part was getting the Canare TS-100E stripper adjusted correctly for the Belden 89259. They have a table of cable types with their dimensions and the height of the adjustment screws for each cable. They also provide a nice metal straightedge for measuring the adjustment screw height. I located the closest cable type (Belden 1506A), set the screw heights to the recommended values for that cable and tried it. I met with only limited success using this approach. The key to success of this operation is to understand how the tool works. Open up the tool and observe the three blades inside. You'll be able to figure out which screw adjusts which blade and which blade affects which cut. Turning the screw clockwise results in a deeper cut, with counterclockwise resulting in a shallower cut. This is an iterative process. Make a test strip. If it's not right, cut off the end you just stripped, readjust the stripper and try again. Repeat until correct. One problem I had even after getting the three blade adjustments correct was that the outer insulator wasn't coming off easily, and there were too many strands of the shield being cut off in the process. This turned out to be from a small error in the "V support" adjustment (the fourth adjustment, screw "A"), which raises and lowers the cable with respect to all three blades and keeps is centered in the circular opening. Once I got this right, the outer insulator came off easily after the strip, and there were much fewer shield strands cut off in the process. Don't be in a hurry during this process. Success will come when you understand the cause-and-effect relationships of adjusting the screws and apply that understanding to get results. Allow yourself plenty of time for this.
A few hints:
1) If you're doing this inside your home and not in a garage, do the stripping over a wastebasket, as many cable fragments and wire pieces will fall out of the tool, making a mess.
2) After each strip, loosen the lid release thumb screw of the stripper to allow the lid to be opened all the way. Shake out the cable debris both from the inside of the tool and the inside of the round handle part. DO NOT PUT YOUR FINGERS INTO THE INSIDE OF THE TOOL FOR THIS, AS THERE ARE SHARP BLADES WHICH CAN CUT YOU!.
3) Place the crimp sleeve on the cable *before* stripping. Otherwise you'll have to slide it over the stripped shield, and many shield wires can get caught on the sleeve in this process. This is annoying, and I did it wrong many times.
4) Use the 0.255 hex crimp for the sleeve and the 0.052 square crimp for the center pin.
5) When crimping the center pin, partially close the tool before crimping to allow the opening to guide the pin into place. Push the cable toward the tool in the process. This will prevent gaps between the pin and dielectric. Do the center pin crimp in an area with good lighting. The center conductor crimp is harder to get right than the sleeve crimp. The sleeve crimp is a slam dunk.
6) If you can, buy the B11016D pins separately from the rest of the parts (Markertek.com). Order extra pins, as they are easy to drop, and it's also possible to damage them by inserting them into the crimp tool improperly without noticing it. I dropped a couple of them into the wastebasket accidentally, and wasn't about to rummage throught the trash to find them. I also damaged one due to an incorrect insertion into the crimp tool.
7) After crimping the center conductor, you may be alarmed to see that it's at an angle with respect to the cable. This seems to be a result of the flexibility of the stranded center conductor allowing inadvertent bending of the center conductor during the crimping process. In my case when this happened, it was completely harmless. I just straightened it and it was fine.Hopefully this info will be of use to someone who wants to build their own interconnects using this combination of cable and connector. Happy DIY'ing!
