Delrin rod, does it need tapping?
 

Hi.

Having never used delvin before, I'm thinking of making my own links from some 10mm rod. I would like to know if it needs to have a thread cut into the end (tap and die), or if drilling a slightly smaller hole for the screw would be ok?

Thanks in advance.

Neil. :)

Either way works. The threads will hold better though. "thumbsup" Just make sure you use the proper # drill bit. Just a side note, 3mm is #39 or a little tighter 3/32.

You're a star, thanks for the reply... "thumbsup"

I always tap my delrin links.

Check out JeepinDoug. He sells a bushing that allows you to drill the hole in the center of the rod. His 3/8 bushing is about what you need for the 10mm rod.

http://www.rccrawler.com/forum/tools-supplies/150200-link-drill-bushing.html

I generally tap about 1/2 the distance needed. Screws start easier but still have the holding power. Alot depends on the size drill you use. a few thou bigger and you wont need to tap go smaller you might need to...

Absolutly.

JeepinDougs drill bushing is awesome.

http://i380.photobucket.com/albums/o...dThread047.jpg

http://i380.photobucket.com/albums/o...dThread051.jpg

Fast easy and perfect every time. "thumbsup"

If I have a tap handy,I'll tap them. If not,I drill a 2.5mm hole and use a 3mm bolt to form tap the threads. Forming the threads with a bolt,the bolt will thread in allot tighter,sometimes that good,sometimes it's bad. At times,I've had the hex head strip out,probably partly due to wore out hex drivers.

Each build I do gets 2 set of screws, the mock ups and then the final draft set. I have thronw out many stripped screws from raw tapping with just the screw. Just a lil bit to small of a hole and oopps stripped.
So just in case I replace all screws during final reassembly. Im kinna picky. When its done I plan on going to play not repair.....

As matter og fact I try to at least tap some starting threads on my rodends helps to get them threaded straight. I can see how a few turns of the tap wont hurt,, but it has made my life easier lol:)

I always tap delrin. I like being able to take things apart without cursing and throughing stuff:lol:

x2 I always tap them.........

I tap them and sometimes ill use thread locker if its near

Loks like I'll have to get me a tap and die set. Would this one be ok? http://cgi.ebay.co.uk/20-PC-TAP-AND-...3A1|240%3A1318


***Edit, just bought this one.... http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA:IT&ih=001

That looks like it will do great for delrin. It says for metals also, but I didn't see a brand listed so it's hard to say the quality of them. Just be sure that if you tap metals with them, no matter how thin, use cutting oil of some type. Crisco, shock oil, hydraulic fluid, etc all work. Basically any viscous fluid that will suspend shavings "thumbsup"

Thanks Homer.

It arrived today, already tapped some aluminium with success. I'll remember your oil tip for next time...."thumbsup"

For Aluminum work Auto Tranny Fluid (ATF) is one of the best lubricants. Definitely use lube when working metal. You will break your tap eventually if you do not. I have yet to "wear-out" a tap they usually break because of improper technique either a lack of lube or too small of a pilot hole.

BTW, a longer than you need screw and a few scores with a cutting disk or a sharp edged file you can make a tap for those "in a pinch" moments. Use this technique lots, after I've broken my tap... :roll: