VN-42 Not Driving VNails - mostly AGAIN

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Larry Peterson

Larry Peterson

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I had an issue a couple of weeks ago with my VN42 not driving nails and it was fixed - or so it seems. Here is the thread that talks about that. https://www.thegrumble.com/threads/vn-42-not-driving-vnails-mostly.88189/ Problem - VN-42 Not Driving VNails - mostly

It was fixed by replacing the Piston Driver Blade. That fixed the problem - sorta.

Since then it has worked partially. When I start up in the morning, it will drive the vnails for 2-3 frames and then take a break. literally. It will drive a vnail and then for the next one in won't. If I let it rest/reset/rejuvenate itself for a couple of minutes and then go back, it will drive a single vnail and then it won't so i let it "rest" for a couple of minutes and its good to go for exactly one vnail. So I drive 1 vnail, go do something else for a couple of minutes, drive 1 vnail, etc. Not very productive.

So this morning it appears to have gone on a permanent break. I did one frame normally and one the second frame it went into its drive, then rest routine. I go the second frame done and part of a third and now it won't drive vnails at all.

So it appears that some other component has gone bad.............but which one. Here are a list of replacement components the FT sells. Hopefully it is one of them.

Foot Pedal,Touch Lever, Pushbutton Control Valve (732290002)​

732290002_ddc485f6-db56-476c-abbd-9fc9b98d0423_450x.jpg


There is another control valve 732440003 that isn't listed in the store. The VN42 uses 3 of them.

Pressure Regulator (735630002)​

Product Number: 41-599​


735630002b_73fd616b-7640-446f-9ed0-afd5ef840c14_450x.jpg


I replaced this a few years ago.

Soft Clamp Regulator (735130006)​

735130006_99f1fd73-9e88-4424-b811-87d41d4b6ea7_450x.jpg


Solenoid/Valve (732140004)​

732140004_450x.jpg


That's basically all the replacement parts that they sell at https://shop.fletcher-terry.com/collections/pneumatics Pneumatics | Shop Fletcher Terry

Any suggestions. I am apparently dead in the water until I figure this out.

BTW, I do have sufficient pressure. When the vnail doesn't drive it sounds like there isn't enough air pressure to drive it but the pressure gauge reads OK (about 100 psi).

One of the suggestions in the manual is an excess of water or oil and to
"Remove the surplus of oil and water from
the valves by disconnecting the air lines
one by one, forcing out the water with
the air"

There are a million lines. not sure how to go about this. Has anyone else done this?
 
Larry although there are a number of components that can cause Alfamacchine firing issues the main one is the control valve, there are 3 control valves fitted to your machine and each one controls a specific movement:
Hammer firing
Vertical clamping
Horizontal clamping

If you are confident in working on your machine then the easiest and free way to determine whether it is the valve causing issues is to swap the Hammer firing valve with the Horizontal clamping valve as the valves are identical, this way if the valve is at fault then the fault will transfer itself to the Horizontal clamp and the Hammer will fire correctly.

if this confirms the valve is faulty then just purchase a new valve or a control valve seal kit at a later date.

(P.S, always take a photo before swapping any valves as then you have a visual record of where the pipes go)

Good luck!

Mark
 
Thanks for the help. In looking at the diagram below, it appears that the middle control valve (#19) is the one that controls the hammer firing. It also looks like the bottom air feed for each valve comes from a common source so I don't need to change those out when I test. I can't tell from the diagram which is the vertical clamping and which is the horizontal so I will have to look closer tomorrow when I try this.


vn42PneumaticDiagram.jpg
 
The schematic diagram shows the valve on the left is the hammer valve, the middle one is the vertical clamp and the right one the horizontal clamp.

(the default layout on the machine is the lowest down of the 3 valves is hammer and the top one of the 3 is the horizontal clamp)
 
Hi I was hoping someone could assist me I have a problem with an alpha machine.

As soon as I put wedges in my machine the piston will not drive a wedge into the frame.
It won't even drive a wedge when there is no frame.

If there is no wedge in the magazine the piston will drive perfectly fine.
Any idea what I can do?
 
If the piston moves as vigorously as it seems like it ought to with no nails inserted, then almost certainly the "nailing head" that guides the nails into the frame has some (or a lot) of crud in it. Thankfully, you can take it out, then take it apart and clean it. There might even be a nail stuck in there, which could happen from one of two reasons I can think of:
1. The afore-mentioned crud (usually glue).
2. the thing has several trillion nails shot through it and it has worn so much that there's room for two nails to start the journey, but not enough to complete it.

So, take it off, take it apart and see what you have. If it's just crud, clean it and put it back together. We just had this situation in the last week or so. If there's a nail plus crud, ditto. If there are two nails, buy a new "nailing head". They aren't cheap, because they are made of hardened steel, but way cheaper than a new machine.

This is a manual for our Inmes 5P underpinner, but I expect most if not all underpinners work on the same general principle. Look at pages 15-16 for how to remove, disassemble and clean the nailing head. If your machine is different, as I suspect it is, @Larry Peterson may well have a manual for it on his site.

 
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David Waldmann said:
If the piston moves as vigorously as it seems like it ought to with no nails inserted, then almost certainly the "nailing head" that guides the nails into the frame has some (or a lot) of crud in it. Thankfully, you can take it out, then take it apart and clean it. There might even be a nail stuck in there, which could happen from one of two reasons I can think of:
1. The afore-mentioned crud (usually glue).
2. the thing has several trillion nails shot through it and it has worn so much that there's room for two nails to start the journey, but not enough to complete it.

So, take it off, take it apart and see what you have. If it's just crud, clean it and put it back together. We just had this situation in the last week or so. If there's a nail plus crud, ditto. If there are two nails, buy a new "nailing head". They aren't cheap, because they are made of hardened steel, but way cheaper than a new machine.

This is a manual for our Inmes 5P underpinner, but I expect most if not all underpinners work on the same general principle. Look at pages 15-16 for how to remove, disassemble and clean the nailing head. If your machine is different, as I suspect it is, @Larry Peterson may well have a manual for it on his site.

Click to expand...
The piston head is brand new and have just replaced it today everything is clean as I have cleaned all parts while replacing the piston head
 
Jamil said:
The piston head is brand new and have just replaced it today everything is clean as I have cleaned all parts while replacing the piston head
Click to expand...
There are two parts that need to operate - the "hammer" and the "guide". Did you take the "guide" apart? I can't imagine one being made from a solid block of steel, as the opening has to be precisely milled and I can't think of a machine capable of doing so in a solid piece.

Af you did, and it is all clean and not worn, my next suspicion would be the nails themselves. Are they the same brand as the machine? If not, get some name brand ones and try them. Yes, they are often more difficult to source and more expensive, and that may not be the answer. But, it might be. Or maybe some other non-branded nails - maybe the batch you have is a bad one.
 
Taught of adjusting the guide, could possibly be out of alignment.
Will try a new batch of staples as well.
I use the alpha staples mostly 7mm and 10mm.
I appreciate the help. 👍
 
Jamil said:
Taught of adjusting the guide, could possibly be out of alignment.
Will try a new batch of staples as well.
I use the alpha staples mostly 7mm and 10mm.
I appreciate the help. 👍
Click to expand...
Was the VN42 working before and it just stopped working now?
I have used a number of Alfa,Mitre Mite, ITW v-nailers although I am most familiar with the VN-2 and the VN2+1and I have some experience with the VN42.
Do you have the factory v-nail heads for 7mm and 10mm (and 12mm and 15mm if you are using them)?
Those v-nail heads are $120 each now...:shutup:
I used to complain when I bought them in the past when they were $80 each.:icon11:
Screen Shot 2023-04-25 at 10.59.08 PM.png
Screen Shot 2023-04-25 at 10.56.54 PM.png
 
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Jamil said:
The piston head is brand new and have just replaced it today everything is clean as I have cleaned all parts while replacing the piston head
Click to expand...

Did you fit the new hammer piston the correct way round? half of the hammer end shaft has a raised lip and it is this lip that makes contact with the V nails.
 
The lip is positioned where the wedges are loaded so when the piston is fired the lip is directly under the wedge.
Is this correct.
It was working perfectly fine before the piston was replaced
 
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