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Getting finish into a double wrap
Posted by:
Ricardo Ortiz
(---.sd.sd.cox.net)
Date: July 28, 2019 06:59PM
Well guys I have a funny feeling something fishy is going on here. I rewrapped a used Calstar 700H with red metallic base and a double guide wrap. 1st wrap is a "C" size then a size "D" over the "C". I used Flex Coat Lite thinking is has a thinner viscosity and will get down through both wraps and to the blank. I warm the wraps with a heat gun, then I pour on the finish and I tried to "push" the finish in with the brush. I didn't notice the finish sinking in, maybe because I put a large brushful on to sink in?
I have seen in the past people wrap the "C" and coat with a light finish and wrap the "D" and then recoat. That may be an old technique. When I wrap I do use a bit of tension, could I be blocking the finish from getting in with a tight wrap? What are the new techniques that I can use to avoid this? Is my 700H now a 196 with weak wraps?? Re: Getting finish into a double wrap
Posted by:
Tom Kirkman
(Moderator)
Date: July 28, 2019 07:21PM
Well you aren't going to "push" finish into the wrap. What you needed to do, was use a finish with the longest pot life possible so that it would have adequate time to soak into the wraps as deeply as possible. Have to keep in mind, that every minute that passes the finish is getting thicker. Heating it only thins it momentarily, whereupon the set and thickening is then speeded up.
I tend to put a very light application of epoxy on the base wrap. Just enough to wet the threads, not enough to build any depth. Let set for until no longer tacky and then overwrap and finish that. Or... you could apply a coat of CP to the underwrap and wrap and finish over that. And no, this does not create a "weak" wrap. ............. Re: Getting finish into a double wrap
Posted by:
Donald La Mar
(---.lightspeed.lsvlky.sbcglobal.net)
Date: July 28, 2019 07:30PM
Finish epoxy adds little strength to thread wraps. The finish protects the thread from moisture, dirt, grime and abrasion, and with some finishes UV.
Generally, the more thread tension and the more the thread is packed the less the epoxy finish penetrates. This is rarely a problem unless the wrap is to be a clear wrap. Some finish epoxies can be thinned with acetone or DNA which reduces the finish viscosity but can have unknown downside impacts in addition to extending the epoxy cure time. A light coat of epoxy to the under wraps before making the guide wraps might be an "old technique" but it works well most evry time. Re: Getting finish into a double wrap
Posted by:
Nick Lam
(---.lmi.net)
Date: July 28, 2019 07:33PM
I wouldn't warm the blank and then put finish on, rather reverse that order. Put the finish on, then warm it. The finish will absorb the heat so it doesn't transfer as much to the blank, also thinning it out considerably allowing it to soak into your wraps.
Best of luck, Nick Re: Getting finish into a double wrap
Posted by:
Bill Lewis
(181.179.19.---)
Date: July 29, 2019 08:30AM
All I make are double wrapped rods. The easiest thing for me and the best results are obtained by putting a coat of epoxy on each wrap before proceeding. One side benefit of using epoxy after each wrap is the next wrap goes on much easier and faster. This is possibily due to the fact that I use only size A thread for all wraps? Bill Re: Getting finish into a double wrap
Posted by:
roger wilson
(---.hsd1.mn.comcast.net)
Date: July 29, 2019 02:27PM
Ricardo,
10-4 on the previous comments. After each layer of wrap, apply a thin coat of finish. After the finish has been applied, slightly heat the finish to let it flow and penetrate. Let it cure overnight and then do the top wrap and repeat the thread finish. Take care Re: Getting finish into a double wrap
Posted by:
Anthony Unger
(---.15.232.186.res-cmts.ovr.ptd.net)
Date: August 01, 2019 07:41PM
A little off topic, but relevent i guess..
I just finished my first closed wrap, whats the best approach for finishing? Im assuming CP, then finish, im having a nightmare with the epoxy over the wrap.. Alot of bubbles.. And lack of penetration.. Im going to sand Tommorrow and apply a 3rd coat.. Only reason i bring this up on this thread is doing layers isnt really an option, yet thats kind of the only option you guys are giving it seems.. Re: Getting finish into a double wrap
Posted by:
roger wilson
(---.hsd1.mn.comcast.net)
Date: August 01, 2019 08:55PM
Anthony,
Very gentle heat will drive out the bubbles, thin the finish and let it all penetrate. The key is GENTLE heat. Too much heat and you boil the finish and it is ruined. Be safe If you look at manufacturing tour videos of rod building shops you will see every one does a flame over the finish after application, to drive out any few bubbles, thin the finish and to let the finish level. All of the rod shops in town do the same thing when building. Just a pass of flame over the freshly applied epoxy to take care of the problems that you have listed. Re: Getting finish into a double wrap
Posted by:
Anthony Unger
(---.sub-174-201-18.myvzw.com)
Date: August 01, 2019 09:01PM
I do tend to overheat.... Sorry, only registered users may post in this forum.
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