Savvio Pen Finally Filled, But Something's Off

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lakelife13

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Last month I asked this community for pen suggestions. After looking into it and reading up, I went ahead and spent a bit more to get 2 Savvio pens. My thinking was that a more reputable brand would give me peace of mind, and I really do believe quality follows price.

So yesterday, one of my research vials ran dry, and I decided to move that research fluid into one of the Savvio pens.

Once it was loaded, I wanted to verify accuracy. I took an EasyTouch 30g .3ml 8mm needle insulin syringe and inserted it into the pen's end, the same spot where a pen needle would go.

I dialed 5 units and pushed… the insulin syringe only reached 3 units… alright, maybe I messed up somewhere. I tried again: dialed 5 units, pressed the pen button slowly, and the syringe only made it to 4 units.

I did prime the syringe by pulling in air before sticking it into the pen.

Anyone know other testing methods? Could I be making a mistake? Is fluid being lost inside the syringe's 8mm needle because it's too long? Could these pens be counterfeit?

I haven't touched the second pen yet—it's still boxed—but I'm pretty disappointed that I spent so much on my very first 2 pens.
 
When I check whether a pen works, water is the only thing I run through it. (no point burning through peps!)

Before you relied on the syringe to test, did you draw water in and push it back out a handful of times? That step changes a lot in terms of how completely it fills during a test.
 
CandyCap said:

When I check whether a pen works, water is the only thing I run through it. (no point burning through peps!)

Before you relied on the syringe to test, did you draw water in and push it back out a handful of times? That step changes a lot in terms of how completely it fills during a test.
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Yeah, skipping the pep crossed my mind, but it was sitting right there and easier, so I just went for it lol

With the second pen still in the box, I’ll give water a shot and fill the syringe several times. I’ll come back with an update
 
lakelife13 said:

CandyCap said:

When I check whether a pen works, water is the only thing I run through it. (no point burning through peps!)

Before you relied on the syringe to test, did you draw water in and push it back out a handful of times? That step changes a lot in terms of how completely it fills during a test.
Click to expand...
Yeah, skipping the pep crossed my mind, but it was sitting right there and easier, so I just went for it lol

With the second pen still in the box, I’ll give water a shot and fill the syringe several times. I’ll come back with an update
Click to expand...
I have a cartridge that's only for water, which I use when testing. It's marked "test" so I can tell it apart. You can use any cartridge that's already been used. For getting the syringe ready during testing, I've found that warm water gives the best results. Fresh syringes often resist both pulling and pushing, so "loosening" it up is a key step if you want the test dose to be accurate.
 
I filled a cartridge with water, then flushed the insulin syringe with water several times before I began testing. I tried 3 separate tests using various doses. All of them came out inaccurate. I filmed the final tests, but I can't upload the videos here. According to the insulin syringe, the amount delivered is roughly .5 to 1 unit less than what I dialed on the pens. It's only a small gap, yet for what these pens cost, that gap shouldn't exist.
 
RetCurious said:

If something truly seems wrong, reach out to the seller. Did you take a look at the second one?
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The same morning as the test, I emailed them, and I'm still waiting to hear back. Both pens were also tested, yes.
 
CandyCap said:

When I check whether a pen works, water is the only thing I run through it. (no point burning through peps!)

Before you relied on the syringe to test, did you draw water in and push it back out a handful of times? That step changes a lot in terms of how completely it fills during a test.
Click to expand...
This exactly.

Run your test again, but this time fill the syringe first and then empty it. A brand-new syringe has stiction that will skew the result.
 
RetCurious said:

If something truly seems wrong, reach out to the seller. Did you take a look at the second one?
Click to expand...
The vendor got back to me. Their response was that when a dose is below 10 units, being off by 1 unit either way still falls inside ISO pen standards, and for anything above 10 units the allowed variance is 5% of the dialed dose.

So I suppose that means they are within the standard?
 
I avoid doses that tiny. For me, 10 units is the floor. I prefer them even bigger. When I can pick, 20-25 is the sweet spot.
 
lakelife13 said:

Last month I asked this community for pen suggestions. After looking into it and reading up, I went ahead and spent a bit more to get 2 Savvio pens. My thinking was that a more reputable brand would give me peace of mind, and I really do believe quality follows price.

So yesterday, one of my research vials ran dry, and I decided to move that research fluid into one of the Savvio pens.

Once it was loaded, I wanted to verify accuracy. I took an EasyTouch 30g .3ml 8mm needle insulin syringe and inserted it into the pen's end, the same spot where a pen needle would go.

I dialed 5 units and pushed… the insulin syringe only reached 3 units… alright, maybe I messed up somewhere. I tried again: dialed 5 units, pressed the pen button slowly, and the syringe only made it to 4 units.

I did prime the syringe by pulling in air before sticking it into the pen.

Anyone know other testing methods? Could I be making a mistake? Is fluid being lost inside the syringe's 8mm needle because it's too long? Could these pens be counterfeit?

I haven't touched the second pen yet—it's still boxed—but I'm pretty disappointed that I spent so much on my very first 2 pens.
Click to expand...
For a pen that stays within +/- 0.5u, the Allstar Jr is an option since it does 0.5 increments, though its ceiling is 30u. In general I aim for pins between 10-30 units so this issue is less of a factor, and I figure on roughly +/-1u. There's a V2 pen sitting unused in my stash that consistently loses the first unit.

On top of that, check thoroughly that not even the smallest bubbles are present. Once compressed, they reduce the dose. Chilling the water can help them dissolve. Stiction tends to cause fewer headaches with manual pens, whereas autos such as Bird, Gansu, and Convi are pleasant to use but may run VERY slowly or jam.
 
From what I can tell, pretty much every pen struggles when the dose is that tiny. The vendor's stance that being off by about 1 unit is acceptable makes sense to me. Try testing again around 15-20 and make adjustments more gradually. In my opinion, the rubber stopper inside the cartridge takes a while to respond to pressure, particularly when doses are small.
 
Strange. I picked up a low-cost $15 V2 not long ago and ran a check using 5 units — it matched perfectly! I was genuinely caught off guard since I figured it wouldn't be reliable. Any idea what made yours inaccurate?
 
RetCurious said:

From what I can tell, my Savio tracks perfectly when I go up in 10 unit steps. 🤷‍♂️
Click to expand...

I ran multiple tests on my Savvio, using everything from low doses up to high ones, and not a single dosing problem came up. The thing was so dependable that testing it eventually just felt tedious.
 
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