Pfaff 145 h3 reverse stitch length shorter than forward

[ThomasBH]

So I've spend some time fiddling and reading manuals / watching youtube videos.

1. I adjusted the needle bar height to be the exact height of the outer walking foot so that it wouldn't collide, but this caused other issues, namely the hook point did not meet the scarf to grab the upper thread properly. Made some terrible sounds and broke a needle. I could not find a manual for the 145/545 mentioning the distance the needle bar should be at bottom dead center (BDC), but in a 1245 repair manual it mentioned 15mm. It was set to 15mm before I made these adjustments, so I just returned it back to 15mm. I am assuming that this aftermarket welting foot is the issue and am hoping the proper Pfaff foot doesn't strike. Can anyone confirm what the 145 H3 needle bar height should be set to?

2. Watching this video (also for a 1245) it states that the needle hook should be right in the middle of the scarf. My machine seems to be slightly lower than this. It mentions the needle bar should be at BDC, then 2mm up for the hook to meet the scarf. Mine is probably 3mm up, however it seems to be working fine. I also notice that the hook also hits and deflects the needle slightly, maybe 0.5mm. I see in another Cechaflo 1245 video he has his 1245 hitting the scarf slightly. Should I be concerned with this? Should I adjust it to be exactly 2mm and not touch the scarf?

3. Relating to both 1 & 2, my machine is supposed to be using the 134-35 needles but the previous owner gave me about 10 packs of 135-17s, which are about 1mm longer. So maybe he had timed the machine for the longer needles? Maybe because they were more available? I am going to try using one of these to see if it works any differently.

4. Will any of the above adjustments actually affect the forward to reverse motion of the stitch length?

 

[Johnny]

Thomas

1. Can anyone confirm what the 145 H3 needle bar height should be set to? My machine is a H4 and uses 190 needle system. I can give you that dimension if you want it when I get home.

2. Should I adjust it to be exactly 2mm and not touch the scarf? The needle bar should rise 2mm (for a C model machine) and should not touch the hook about .1mm clearance.

3. Timing for 134-35, 135-17 needles. If the only difference is the 1mm length then set the needle bar height using that needle. I probably would start with the recommended needle system for your machine.

4. Will any of the above adjustments actually affect the forward to reverse motion of the stitch length?  In my case I could not get the reverse stitch length correct, I checked and made adjustments from the setup document and then I was able to get the reverse stitch length fixed. My needle bar height was way off and I am amazed it even sewed.

Try this with a fine black marker place a line 1.5mm above the top of the eye of the needle and install it then bring your needle bar up 2mm the tip of the hook should be at the black line if not loosen the needle bar screw and adjust it so that it is.

I am wondering if the reverse stitch length is not correct because of the welting foot and not having a regular foot installed?

I have an extra set of pressor feet if you want I could send them to you and you can send them back when you get yours. I am happy to help if you like send me a pm and I will give you my number maybe be easier to help over the phone. 

Johnny

Edited February 14, 2022 by Johnny
Typo

[Johnny]

Thomas

Can anyone confirm what the 145 H3 needle bar height should be set to? Mine has 20mm at bottom, again my machine is a H4 it has 14mm pressor foot clearance.

Once I had the timing right I was able to adjustment the eccentric to correct the reverse stitch length. One thing I might add to adjusting the eccentric is to place reference marks on it to keep track of the direction and how much I moved it, do little bit at a time.

Don't give up these are great machines!

Johnny

[ThomasBH]

20 hours ago, Johnny said:

Johnny, thank you for the detailed reply!

1. Can anyone confirm what the 145 H3 needle bar height should be set to? My machine is a H4 and uses 190 needle system. I can give you that dimension if you want it when I get home.

I’d appreciate that, but I think the H4 would have a significantly higher needle bar proportional to the extra needle length.

2. Should I adjust it to be exactly 2mm and not touch the scarf? The needle bar should rise 2mm (for a C model machine) and should not touch the hook about .1mm clearance.

Upon more fiddling the hook point was touching only the eye of the needle, so I lowered the needle bar so that it will arrive in the middle of the scarf  

3. Timing for 134-35, 135-17 needles. If the only difference is the 1mm length then set the needle bar height using that needle. I probably would start with the recommended needle system for your machine.

Agreed that I should be focus on using the recommended needle and that is what I’ve been doing for my adjustments. 

4. Will any of the above adjustments actually affect the forward to reverse motion of the stitch length?  In my case I could not get the reverse stitch length correct, I checked and made adjustments from the setup document and then I was able to get the reverse stitch length fixed. My needle bar height was way off and I am amazed it even sewed.

Try this with a fine black marker place a line 1.5mm above the top of the eye of the needle and install it then bring your needle bar up 2mm the tip of the hook should be at the black line if not loosen the needle bar screw and adjust it so that it is.

I am wondering if the reverse stitch length is not correct because of the welting foot and not having a regular foot installed?

This is hopefully the issue and nothing harder to fix. Same with my my needle bar striking the outside foot. I think my needle bar is arriving 1.5mm above the eye, but I will try this trick with the marker.

I have an extra set of pressor feet if you want I could send them to you and you can send them back when you get yours. I am happy to help if you like send me a pm and I will give you my number maybe be easier to help over the phone. 

Thank you for the offer and will take you up on it if mine do not arrive (I’m leaving for two weeks with work today,  so theoretically they’ll arrive within that time)

Certainly I’m close to my wit’s end. I feel like I have done virtually everything recommend and the timing should be on.

-the hook point meets the middle of the scarf approx. 3mm up from BDC

-I reduce the needle bar height to match the above once the hook point was perfectly centre of needle, I think it’s around 14mm now. This has now worsened the striking of that outside foot.

-The walking feet seem to be arriving at the feed dogs at the correct time after adjustment

-While this machine is new to me I hadn’t fully tested it before having the above issues but the thread tension is having a lot of issues as well. I’ve played with the upper and lower many times and it’s just not working right. I definitely have to have the upper way tighter than a machine should and it still won’t balance the knot in the middle. Sometimes I almost think I got to cooperate, then it causes tension balance issues on turns, or a will just be inconsistent. This has me thinking my timing is off, but I followed that YouTube video very closely

So many issues!

Thanks for any additional help! I wont be able to touch the machine for a few weeks by the way.

 

20 hours ago, Johnny said:

 

 

[ThomasBH]

After much more fiddling and a local sewing machine technician stopped by I seem to have gotten my 145 into a state that I'm pretty happy with.

While the forward / reverse stitch length was the most noticeable issue when I first received the machine, after additional testing the inconsistent tension was of much more concern. My forward and reverse stitches are still not consistent, especially if I change the stitch length. (I have decided to just leave it at '2' for most purposes where I have adjusted it to match fwd/rev for at least 4 or 5 stitches)

The tech found four issues:

1. The hook/bobbin assembly was not fully seated in its slot (maybe a couple of mm higher than it should've been) This caused this part to wobble:

2. The hook/bobbin assembly position needed to be rotated slightly(using the right hand screw that allows some horizontal adjustment)

3. The throat plate had been damaged/enlarged where the hook/bobbin case slots into it on the underside, this caused loops to form at the wrong time. Here you can see the closest throat plate with some damage/odd shape and the new binding throat plate in the rear of what it should look like.

4. Micro burs / sharp edges on some components

Thank you all for your help, much appreciated. I have tried to include lots of photos and descriptions to help any future users facing issues. Feel free to DM me if you need any help yourselves.

Also, for those interested you can get very cheap binding sets to have a cylinder arm style synchronized binder, this would work on a 145, 545 and 1245.

https://www.aliexpress.com/item/1005003451959950.html?spm=a2g0o.9042311.0.0.14334c4d3mdpTs