Messages

I think I recall a Pfaff twin-needle single-bobbin machine that sewed parallel seams on the top and zig zag on the bottom, but can't find a reference to the machine now.

For similar threads, pun not intended, on another forum that might help, you could try the following in google:

tension problem in reverse site:leatherworker.net

As for skipping stitches, here is a link to another forum. The last post has a link to a sewing machine troubleshooting pdf that has 31 causes and solutions for skipping stitches.

http://leatherworker.net/forum/topic/59405-new-juki-1541s-keep-jamming/

Here is a link to an adjustment manual.

http://keysew.com/Webpages/Owners&PartsBooks/OwnersBooks/Pfaff1245_AdjustmentManual.pdf

Might not be helpful but if you try the following google search, there are a few posts that mention the Pfaff 1245 and thread fraying:

pfaff 1245 thread fraying site:leatherworker.net

Tim,

As for timing the machine, here are some videos that although not precisely your machine might be helpful.

Consew 225 Hook Timing:
https://www.youtube.com/watch?v=1wNBPX8i524

Needle-guard Adjustment:
https://www.youtube.com/watch?v=9EWODLVlOxo

Adjusting Juki LU-563 class machines:
•   Change stitch length
•   Set stitch length indicator
•   Adjust foot lift height, balance and timing
•   Adjust rocker arm position
•   Center needle position in feed dog hole
•   Adjust feed dog height
•   Adjust maximum possible stitch length
•   Adjust for equal Forward/Reverse stitch length
https://www.youtube.com/watch?v=iiaaT1npYrQ

BTW, Uwe has made several other really helpful videos.

... what was the name of the Guide ?  or  key word to search ?

The name of the file is (was) sewing_troubleshooting_chart.pdf. The URL was:
http://designer-entrepreneurs.com/blog/illustrations/sewing_troubleshooting_chart.pdf

The printed name in the file is "Sewing Machine Troubleshooting Chart"

The file disappeared from the Web about a year ago. I've searched for the file several ways and cannot find even a cached version. Actually, I think I recall that another section of the file was posted on this forum several years ago and I was able to find the full version then and saved the file

Anyone can send a PM and I'll email the file.

Copied below is a list of problems and causes and solutions from a 25 page trouble shooting chart that seems no longer to be available on the Web.

Loops or Knots on the Underside of the Fabric
The lower thread lies straight on the underside of fabric and the upper thread appears there in form of loops or small knots.
1.Cause: The tension of the upper thread is too weak or the tension of the lower thread is too tight.
Solution: Tighten the tension of the upper thread, or loosen the tension of the lower thread, until the tensions of both threads are correctly balanced.
2.Cause: There are dirt, lint or pieces of thread between the Tension Discs.
Solution: Take apart the upper tension, clean the Tension Discs thoroughly, then replace the upper tension and adjust it correctly.
3.Cause: The upper thread has cut deep grooves into the Tension Discs.
Solution: Replace the defective Tension Discs with new ones.
4.Cause: The Bobbin Case is not threaded correctly. The Bobbin unwinds itself in the wrong direction.
Solution: Thread the Bobbin Case correctly.
5.Cause: The head of the Tension Adjusting Screw of the Bobbin Case protrudes too much and catches and retards the upper thread.
Solution: Adjust this screw correctly. If this condition continues to persist, smoothen the head of this screw with fine emery cloth or replace the defective screw with a new one.
6.Cause: The stitch hole in the Throat Plate or Feed Dog is too small.
Solution: Replace the Throat Plate or Feed Dog with one that has a larger stitch hole.
7.Cause: The point of the Needle is bent over ("hooked point").
Solution: Replace the defective Needle with a new one.
8.Cause: The Bobbin is not evenly wound. It unwinds itself irregularly.
Solution: Replace the Bobbin with one that is wound evenly.
9.Cause: The Bobbin is damaged or bent and does not revolve freely and evenly.
Solution: Replace the defective Bobbin with a new one.
10.Cause: Lint or dirt in the Bobbin Case prevents the Bobbin from revolving freely.
Solution: With a pointed pin remove all dirt from this part. Clean with kerosene and dry thoroughly before replacing in the machine.
11.Cause: The needle is not correctly timed in relation to the Loop Taker (Hook).
Solution: Make certain that the Needle is pushed all the way up into the Needle Bar and held there firmly. Adjust the point of the Loop Taker in relation to the Needle. For "Timing" follow this general rule: The Needle must have risen about 3/32 of an inch from its lowest position at the moment the point of the Loop Taker is just at the center of the rising Needle. At this moment the point of the Loop Taker must be about 1/16 of an inch above the eye of the Needle.
12.Cause: There is insufficient clearance between the Bobbin Case Holder and the Bobbin Case Holder Position Bracket in horizontal axis Rotary Hook Machines. On vertical axis rotating hook types may be insufficient clearance
between tab extending from Bobbin Case to the left and the notch at the underside of the Throat Plate.
Solution: Turn the machine by hand and observe where the upper thread gets caught.
Increase the clearance, where required, by carefully removing material from the component parts of the machine (by means of fine emery cloth). Smoothen the repaired portions with crocus cloth. The heaviest thread to be used must pass freely between these parts.
13.Cause: The mechanism for releasing the upper thread tension is incorrectly adjusted. It releases the tension of the upper thread too early.
Solution: Adjust this mechanism so that the tension of the upper thread is released only during the last moment of the upward motion of the Presser Bar Lifter.
14.Cause: The upper thread gets caught somewhere below the Throat Plate.
Solution: Examine Hook and Bobbin Case with regard to rough spots which may catch the upper thread and retard it, thus causing the loops on the underside of the fabric. Eliminate all rough spots with the aid of an oilstone or with fine emery cloth, and then polish these portions with crocus cloth or on a buffing wheel.
15.Cause: The Thread Take-up Spring (Check Spring) is not adjusted and does not work properly.
Solution: Adjust the Thread Take-up Spring until it has the correct tension and its upward motion is just finished at the moment the Needle enters the fabric.

I've used one to get a needle-thread base setting in case I really screw up the tension. I've never needed to adjust the bobbin-thread tension. I should probably also get that base setting.

Try the following in google for related posts on another forum.

thread tension gauge site:leatherworker.net

Repeatable top and bottom thread tensions can be possible using a tension gauge.

Here are links describing using a tension gauge.

http://www.brother-usa.com/ModelDocuments/Consumer/Maintenance%20Guide/MG_BES_1230AC_1240BC_1241BC_1260BC_1261BC_1262_1263_960BC_961BC_EN_442.PDF

http://jukiindia.com/Item-List/Adjustment_Procedue.pdf

http://sew24.blogspot.com/2012/11/how-to-measure-thread-tension-with.html

... is the 217? a walking foot zig zag.

No, the Bernina 217 is not a walking foot sewing machine. Here's a link to the best description I've found online.

http://www.ashleyandthenoisemakers.com/blog/2015/5/7/bernina-217-review

As the article states, one with the optional cam reader is apparently difficult to find. However, after-market cams can be purchased, and that's were I got the multi-pont, multi-step cams.

Since you are considering a made in China machine, you might not be aware that in addition to the LSZ-1 sewing machine, Sailrite also sells "Professional" machines that seem suitable for sail making and repair. With Sailrite you might get better after sale support than some other dealers.

Here is a link to a Salirite sewing machine comparison chart.

http://www.sailrite.com/PDF/Sailrite%20Sewing%20Machine%20Comparison%20Chart.pdf

The Sailrite forum might have some user experience with these machines.

http://forum.sailrite.com

... with regards to "point" I think they call it, or stitch.

On the word "point" and sail-making -repairing zig zag sewing machines, the reference might be the capability for multi-point, multi-step zig zag often seen on sails.

My Bernina 217 has a cam reader, and I have a three-point, two-step cam and a four-point, three-step cam. I've used the later for UV panel jib replacement on a 36' sailboat 140° genoa. The head also needed replacement. Getting the sail rolled-up and under the arm was a real hassle. Repairing the head and tack of the sail with multiple layers of Dacron, webbing and leather covering was only just possible. The maximum thread size seems to be V-92 for this machine. Elsewhere on the sail, thread size was apparently V-138. Essentially, the machine was only marginally adequate for my skill level and a sail this size. I wouldn't even consider attempting repair on my mainsail.

Depending upon the size of sails, were I to consider sail repair zig zag sewing machine, I'd want to determine the type of sails, size of the sails, the need for multi-point, multi-step, thread size and space under the arm.

In addition to staples, I should have mentioned:

•   HDX 3/4 in. Mini Spring Clamps, I aways have 15 or so clamped on the thread stand for quick access (about 40 cents each from Home Depot)

•   Binder clips from an office supply store, such as 3/4" wide, 3/8" capacity

Not an expert, just DIY. However, to ensure matching fabric pieces on long runs, I layout the project and make either matching fabric to fabric marks or matching small inset cuts using a tool for that purpose called a pattern making notcher. The inset cuts are similar to the little matching triangle notches in dress making, just narrow and shallow.

The worst case I learned from was sewing a 40' finished zipper into a jib cover. The ends of the two sides of the zipper weren't close even though I used seam tape. Stapling, which I also use, was not possible. I unpicked the stitches, reapplied the zipper sides to the fabric with seam tape, checked that the starts and ends were correct, than made matching marks on each side of the zipper to the fabric, and sewed slowly ensuring that the marks on the zipper tape matched the corresponding marks on the fabric.

Update: I should have mentioned that in other situations, I've sewn from the center to the sides to avoid creep.

cute little accessory for sewing seams of varying thickness.

The varying thickness spacers that Virginia mentioned might be similar to the presser foot spacers mentioned in the earlier post. I think that the jean-a-ma-jig comes in only one thickness.

http://www.nancysnotions.com/product/presser+foot+spacers.do