JMW-9/Cartridge Problem

I'm trying to get 1.5 grams on my grado sonata
cartridge, and can't seem to get more than 1-1.25
grams of weight out of the jmw-9 arm mounted
on a scoutmaster. Is their anything i'm missing or do I need a different counterweight?
Did your Grado come with a metal weight designed to fit between the top of the cart and the headshell? If so, that can add the needed weight to the front end to offset the counterweight.

Another option is to contact VPI and get a smaller counterweight for the arm. The last thing you want with the JMW9 arm is to have the counterweight so far forward that it makes contact with the rear portion of the pivot point.
What is the total weight of the Grado Sonata? If it is below 5 grams you will need a lead speacer to increase tracking force. It's very simple. or fabricate a lead spacer or even put blu-takon the headshell. VPI doesn't make a lighter counterweight than that supplie with the Scout
The Scoutmaster comes with a large(ish) counterweight standard. There IS a smaller one available from VPI. I got one from them myself in order to get a satisfactory VTF with the Dynavector 17D which is lighter than than the Grado in question. Blutak will work as a temporary solution. But, unless you are very accurate with its application, it will effect the azimuth of the arm in a negative manner.
I had the opposite problem with my Grado Reference Cartridge.I had it tracking at one point way over spec. at 2.6 grams with my Morch Arm.I realised this when I bought the Shure Precision Stylus Force Gauge SFG-2.
In my case my arm comes with 3 different counter weights
so I was able thru trial and error finally able to get it tracking at about 1.6 grams.I had on to large of a counter weight to begin with,and used my medium and small counterweight to balance things out.
My weights are a bit forward closer to the pivot ,But everything is working fine with my VPI MK3 Morch UP-4 Combo.
I'm not familiar with your arm.Do you have the option of using a heavier counterweight?Your cartridge weighs the same as mine so this may help alot.If not 1 or 2 small lead spacers between headshell and cartridge should help.
Will try to get ahold of vpi today to see about a smaller weight or spacers. I'm using the same shure scale.
I am perplexed at your difficulty. I have the same cartridge & arm and have had no problem dialing in anything between 1.5-2.0 grams using the standard dropped counterweight that came with the turntable/arm from VPI. No additional weight was required. No offense pointing out a seemingly obvious thing, but did you check to make sure all is ok with the Shure gauge? I have had the pivot point get sticky & bind on ocassion.
I had to order another weight than the standard for my Dyna karat.
I just installed a Clearaudio Sigma (4.5gms) on a JMW9 the other day. Clearaudio supplies a lead shim to add in case the counterweight is not light enough for the cart. I don;t know if VPI makes a counterweight smaller then what is supplied with the JMW9. I know they have heavier but not lighter counterweights
I had the same problem using a Karat with my JMW-9. I contacted VPI and they sent me a headshell weight at no cost. Adds weight AND mass. They also recommended against a lighter counterweight as it will further lower the overall mass of the tonearm.
Same problem here, as well, did the same as Jorjen as got the headshell weight from VPI, works well.