Hi Thomas We use a very simple solution.
We simply shorten a normal needle to 6.5 mm and push it into another syringe that has *two *of the white PTFE ferrules made by Hamilton. (We salvage the extra ferrule from another needle.) We use a 22 gauge needle (not 22S, where the S stands for *small *inner diameter). Now you can push the two syringes together and make your LCP. It helps if you tighten the knurled nose-piece to compress the PTFE ferrules before you join the syringes. You have to keep a little pressure on the two syringes to hold them together while you mix up the LCP, or use eg tape. (Which is why we've made a little mixer on a rail, but that's another story.) One nice feature is that you hardly waste any LCP and the needle for dispensing it is already attached to the syringe. Let me know if you need more info or you'd like me to send you a short needle. Best wishes, Patrick On 16 December 2014 at 02:14, Thomas Cleveland <thomas.clevel...@gmail.com> wrote: > > Hi everyone, > > Thanks for the advice. I had, in fact, already ordered some > commercial couplers, but they haven't come in yet, and there was an > experiment I wanted to do today. > > Here's what I found: > > 1. The steel ferrules have an orientation, with a "tight" side and a > loose side. They can be removed by sliding in one direction, but not > the other. Even then, it's pretty difficult. I had to use pliers, > and pieces of needle broke off during the process. The tight side of > the ferrule then needed to be reamed open slightly with a steel tool > before I was able to slide the ferrule onto the other needle. > > 2. Soldering stainless steel is really a pain. > > In the end I got a coupler that seems to work well, but it was a pain, > and it's a bit charred looking. > > Thanks again, > Tom > > > On Mon, Dec 15, 2014 at 6:01 PM, Aaron Thompson > <aaron.a.thomp...@gmail.com> wrote: > > I agree with Jim – purchasing the couplers will get you up and running > much > > quicker. > > > > TTP also sells nice couplers: > > > https://www.ttplabtechstore.com/ttp_ecom/cc/ItemDetails.jsp?@where.ItemID@EQ=3072-01050&sessionkey=# > > > > Aaron > > > > > > > > On Mon, Dec 15, 2014 at 12:38 PM, Bernhard Rupp < > hofkristall...@gmail.com> > > wrote: > >> > >> Tried the RN kludge.... at least I did not get it to work. You cannot > >> tighten the plastic swage lock type sleeves > >> tight enough. On operation the pressure drives the PEEK tubing out of > the > >> compression fit. > >> Maybe if you have a jig that holds the 2 syringes in a fixed position so > >> they cannot move apart it can work. > >> > >> Best, BR > >> > >> -----Original Message----- > >> From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of > >> Daniel Anderson > >> Sent: Monday, December 15, 2014 8:48 PM > >> To: CCP4BB@JISCMAIL.AC.UK > >> Subject: Re: [ccp4bb] Fabricating hamilton syringe coupler for LCP > >> preparation > >> > >> Here's my addition to Jim Fairman's reply: > >> > >> You could use a pair of RN compression fittings (www.hamilton dot com > part > >> number 55751-01) and a segment of HPLC tubing. HPLC tubing within my > field > >> of view can have an inside diameter as small as 0.005 inch. > >> > >> hope that helps, Happy Merry, etc., > >> Dan > >> > >> > >> On 12/15/2014 11:09 AM, Thomas Cleveland wrote: > >> > Hi all, > >> > > >> > I'm trying to put together some homemade syringe couplers following > >> > the published instructions from the Caffrey group. I'm having a bit > >> > of trouble with this part: > >> > > >> > "The stainless steel ferrule of the second needle is removed and > >> > placed on the free end of the coupling needle such that the double > >> > thumb nut is held symmetrically between the two steel ferrules" > >> > > >> > Has anyone done this, and if so, how did you remove the stainless > >> > steel ferrule from the second needle in order to place it over the > >> > first? The stainless steel ferrule appears to be firmly attached and > >> > I'm having trouble removing it. > >> > > >> > Thanks, > >> > Thomas Cleveland > -- patr...@douglas.co.uk Douglas Instruments Ltd. Douglas House, East Garston, Hungerford, Berkshire, RG17 7HD, UK Directors: Peter Baldock, Patrick Shaw Stewart http://www.douglas.co.uk Tel: 44 (0) 148-864-9090 US toll-free 1-877-225-2034 Regd. England 2177994, VAT Reg. GB 480 7371 36
