ryanww Report post Posted January 3, 2018 (edited) I have a new to me Pfaff 1245-706/48 CLPMN. I'm brand new to industrial sewing machines. I found a copy of the service manual, adjustment manual, and owners manual thanks to some older threads on this site. I still have a few questions. A few simple adjustment questions then some more complicated stitching question. I'll try to provide as much information as possible but if I'm missing something or you need more pictures just ask. I'm using 138 bonded nylon thread and a 190 LR size 22 needle sewing through various leathers, 2-3oz veg tan, 3-4 oz upolstry leather, etc. 1) The presser foot height adjustment screws slipped a bit and I've readjusted the height, but my question is should the needle plate be the bottom stop for the presser foot, or is there a metal on metal stop somewhere else? Before I adjusted it the hinge would bottom out on the frame of the machine and the presser foot would not sit on the needle plate. I'll show in a picture. 2) The manual states that the vibrating foot and the needle point should arrive at the needle plate at the same time when set to the longest stitch length. Mine is very close, probably within 1/16 - 3/32" , but everything seems to feed nicely and be timed together. Is this a real critical adjustment? If I adjust the vibrating foot I'll have to adjust the feed dogs too, because those two seem to be in time really nice together. 3) I'm having a few stitching issues. At first the machine was skipping a few stitches. Someone had adjusted the needle height to be be in approximately the right location when the hook spun around, but I re-evaluated the timing and it was off by about 60 degrees according to the service manual. I successfully re-timed it and now it never misses. However I'm having what looks like tension issues. The stitches look like not enough top tension or too much bobbin tension. I've gone through the whole range of tension on needle thread from barely able to pull the thread through the disc to fairly loose. I've also gone through the full range of bobbin tension and it is currently very loose. Adjusting the needle thread tension does change the appearance of the top a bit, but it's still not pulling the lock up from the bottom. I'm 99.9% sure everything is threaded correctly. I'll show some pictures of the stitching. Thank you in advance for your help! Ryan Top Bottom Edited January 3, 2018 by ryanww Quote Share this post Link to post Share on other sites
Northmount Report post Posted January 3, 2018 You should show us your thread path from spool to the needle as well. It is critical to being able to adjust the top tension. Tom Quote Share this post Link to post Share on other sites
Pintodeluxe Report post Posted January 4, 2018 Pull the tension discs off the upper tension mechanism and check them for wear. That can cause irregular tension issues. How does it sew with #92 thread and the same needle? Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 4, 2018 Quote You should show us your thread path from spool to the needle as well. It is critical to being able to adjust the top tension. Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 4, 2018 Quote How does it sew with #92 thread and the same needle? I have not tried it with any other thread. Before I got it, it was sewing nicely with #69 thread using a different needle through synthetic fabric and webbing. I will check the discs for wear, but the issue is not irregular, it's regularly off Quote Share this post Link to post Share on other sites
Northmount Report post Posted January 4, 2018 You don't show the top guide post in your threading pics. If you take a wrap through it, you can further increase top tension. Too small a needle in tough leather makes it hard to pull the knot up into the leather. Where it was doing fine in textile material with 69 thread, it would appear that the combination of thread, needle size and leather you are sewing is at the root of the problem. Try going up to a larger needle size so there is a bigger hole to pull the knot up into the leather. I imagine you have read a number of posts about bobbin and top tension, so you already know that you don't want much tension on the bobbin. Should be easy to pull the thread from the bobbin. Tom Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 4, 2018 (edited) 18 minutes ago, Northmount said: You don't show the top guide post in your threading pics. If you take a wrap through it, you can further increase top tension I do have a wrap around the top guide post. 18 minutes ago, Northmount said: Try going up to a larger needle size so there is a bigger hole to pull the knot up into the leather I will try this. You may be on to something here. From my reading I figured size #22 with 138 thread was a safe bet. The hole punched by the needle is more of a slit than a hole. I don't currently have any other needle sizes or designs so I will have to get some. Edited January 4, 2018 by ryanww Quote Share this post Link to post Share on other sites
RockyAussie Report post Posted January 4, 2018 Just check that you are getting enough foot pressure down. If you have been mostly doing fabrics the foot pressure may be lighter than what that leather needs. If the leather is veg I would expect to see some at least light pressure marks on your sample piece. Just look and see if the leather comes up a tad when the needle is on its way out ....if it does your knots will form on the bottom. Quote Share this post Link to post Share on other sites
chasman52 Report post Posted January 4, 2018 Thanks you for posting. when I was looking up this youtube thread for your Pfaff1245 I realized I also wasn't threading my 1445 take up through both holes. I'm not sure that will help me. Pay attention the part about the tension disks . He goes around the post. It seems logical.. Hope this helped Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 4, 2018 Quote Just check that you are getting enough foot pressure down. If you have been mostly doing fabrics the foot pressure may be lighter than what that leather needs This is entirely possible that the pressure is too light. I will try to increase the pressure. Good tip, thanks! Quote Pay attention the part about the tension disks . He goes around the post. It seems logica I'm not sure where the idea comes from to go around the post. The manual clearly shows not to go around the post. To be sure I've tried it both ways without any noticeable difference. Quote Share this post Link to post Share on other sites
mikesc Report post Posted January 4, 2018 (edited) You should never go "around the post" ( at the tension discs ), it is there just to stop the tension discs from spinning instead of placing tension on the thread by squeezing them.."he" ( in the video ) is totally wrong. to the OP Ryanww..you also have a metal "finger" ( fastened with a screw to the machine body, it is sticking out across the thread path at a horizontal angle ) just above your needle thread guide..You are going behind this ..so your thread is rubbing on the machine body ( it has obviously been doing so for a while, there are other wear lines )try going in front of this metal bar ( so that the thread is resting against it before it carries on down to the needle thread guide ) this will add a little more top tension ( every "smidgen" can help down there )..combing that with what Rocky Aussie and Northmount said should help. Edited January 4, 2018 by mikesc Quote Share this post Link to post Share on other sites
chasman52 Report post Posted January 5, 2018 Mike and Ryan are correct. I should have looked in the manual too. Sorry for my post. Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 9, 2018 I've noticed some improvement with maxing the downward pressure but not much. I ordered some larger needles, but they have not arrived yet. I've tried a lot of different leathers so far. 2-3 oz veg tan, 4oz upholstery, 4 oz oil tanned. I've noticed with the softer leathers it does pull the knot up a little bit more, but not very much. What is a rough guide for top tension? I have it so tight right now I can hardly pull the thread through the machine with the presser foot down. After stitching the pieces tend to cup a little toward the top because the stitches are so tight. I know that's too much tension. Quote Share this post Link to post Share on other sites
RockyAussie Report post Posted January 9, 2018 Hey Ryan, I am no sewing machine expert and I usually work in metric sizes and missed that a bit earlier in the post. The thickness you are trying to sew with that size thread is a bit extreme. I would be trying a thinner thread for the bobbin if that was alright. If you were up at 5oz (2mm) leather you might have more luck but the 138 (20m) thread knotting into the middle on 2-3oz may be a big ask. With your foot pressure ...Test that it lifts smoothly by lifting them by hand from the feet upward. If there is a jumpy feeling you may need to try more oiling or cleaning up the shaft. Also make sure both feet come down onto the plate with similar pressure when fully down meaning that they are both fully extending down. The bobbin will be very loose to take the thickness you are trying and can take a fair bit to get right. I keep a couple of cases to not have to adjust them when I do get them set for a thread thickness. Hope that is some help until some more expert chips in. Brian Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 10, 2018 Quote If you were up at 5oz (2mm) leather you might have more luck but the 138 (20m) thread knotting into the middle on 2-3oz may be a big ask. I'm a little confused, are you saying it would be easier for the knot to pull up with thicker material? Quote Share this post Link to post Share on other sites
brmax Report post Posted January 10, 2018 In the thickness of the pieces being sewn. Meaning the knot would have more room, thus easier to be centered. Floyd Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted January 10, 2018 On 1/9/2018 at 9:20 AM, ryanww said: What is a rough guide for top tension? I have it so tight right now I can hardly pull the thread through the machine with the presser foot down. After stitching the pieces tend to cup a little toward the top because the stitches are so tight. I know that's too much tension. Ideally, you'll want to use the least top and bottom tensions that lay down good looking stitches without puckering the material. There shouldn't be loose thread on the top or bottom, nor should any knots be visible. If the top or bottom thread either puckers the material or produces loose loops, shorten the stitch length until the stitches lay flat. You should select a thread and needle combination that best produces these results. A well equipped sewing room will have at least two spools (one for the top, one for the bobbin) of each color and size of thread that will be used, as well as packs of needles in every size needed to sew those thread sizes. It is usually a good idea to buy the same brand of thread in these sizes and colors. This leads to predictable results. We have dealers who advertise here that stock their brands of thread in matching shades across multiple thicknesses. Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 10, 2018 Quote A well equipped sewing room I'm not there yet, but working on it! I'm really hoping to be able to use 138 on top and bottom because I like the thicker thread look. Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted January 10, 2018 1 hour ago, ryanww said: I'm not there yet, but working on it! I'm really hoping to be able to use 138 on top and bottom because I like the thicker thread look. That should not be a problem for your Pfaff 1245. Just use #160/23 leather point needles. If you use #140/22 needles the holes will be tighter and the tension required stronger. See if you can buy a pack of #150 Pfaff needles. That is a perfect fit for #138 thread. Quote Share this post Link to post Share on other sites
RockyAussie Report post Posted January 10, 2018 6 hours ago, ryanww said: I'm not there yet, but working on it! I'm really hoping to be able to use 138 on top and bottom because I like the thicker thread look. 2oz leather is only .8mm thick. The thread of 138 if measured is near .4mm. Double that for the knot = .8mm. The thicker leather will be a fair bit easier for you dial in to get close to middle. The thinner bobbin thread would also help a lot unless your foot/ timing is out in some way. As Wiz says above your leather should not be pulling together and should want to sit down flat. Quote Share this post Link to post Share on other sites
Uwe Report post Posted January 12, 2018 While you're fine tuning your machine, I'd suggest installing a proper lower thread guide. The one on your machine looks like a homemade replacement for the original, which looks like this: Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 12, 2018 Quote I'd suggest installing a proper lower thread guide. On my list! Thanks Quote Share this post Link to post Share on other sites
ryanww Report post Posted January 14, 2018 Thanks to everyone for the help! The two most effective suggestions were to use a larger needle and to try thicker leather. Moving to a size #23 needle made a huge improvement. Now making top tension adjustments actually makes a noticable change in the stitch. I think I have a good handle on things now but I'm sure I'll have a million questions as I continue to learn. Thanks again! Quote Share this post Link to post Share on other sites
RockyAussie Report post Posted January 14, 2018 Good news Quote Share this post Link to post Share on other sites