I think this applies to both home machine and LA quilting. Is it possible to use a different color thread in the bobbin without having little "dots" show up on the other side? I can't seem to do it at home and my LA quilters say it is nearly impossible for them to avoid having these dots show up. Sometimes it isn't important, depending on colors, but other times it is distracting and rather messy looking.

The other question is mostly a LA question. Frequently I like to include extra blocks from the front into the backing; often I want to center these blocks. But the LA quilter says it is very difficult if not impossible to ensure that the blocks will truly end up centered on the back. Any thoughts on this?

maybe hunt for a new longarmer? but for me at least it is really really hard to do at home. no matter how hard I try. I am just happy if the backing isn't crooked. good luck

I think it is difficult to center it perfectly, but people do it.
You have to really play with your tension to avoid dots.

I have a mid arm (15") maybe if you use a thicker batt it may work but those stitches would have to be perfectly centered in the layers to keep one from showing, when it's washed those needle holes will close up some and make it less visible. when you put a quilt on a frame you do each layer seperate, on a different roller and just can't know for sure that the center of the top and the center of the back is going to roll up equally to hit center to center, side to side is pretty easy but not top to bottom.

[quote=SunQuilts]I think this applies to both home machine and LA quilting. Is it possible to use a different color thread in the bobbin without having little "dots" show up on the other side? I can't seem to do it at home and my LA quilters say it is nearly impossible for them to avoid having these dots show up. Sometimes it isn't important, depending on colors, but other times it is distracting and rather messy looking.

I'm so glad you asked this question. I just thought it was me and my machine. Now I don't feel so bad, and I'll be following what people say.

I am a longarmer and it is very difficult.I have done it once or twice but can't get perfection any more so I go with matching or close to matching thread in top and bobbin.

It is very hard not to get the little dots from the back showing in the front. It depends mainly on the tension. You need to try changing it by very small increments at a time until you get it right. But, it also depend on the threads. Thinner threads behave different than thicker threads and they tend to show different, so the tension that works for one thread will not show for another.

I agree with your longarmer. The way the stitch on our machines is created makes it very hard, near impossible to not have the dots show. And you can get the tension just perfect but if you change anything about the FMQ you're doing, the dots will show again. It's just easier to match the top and bobbin(same color) or use variegated threads.

Just never use white or light batting and quilt on black fabric--you will get bearding--how well I know this. Long arms use a big needle.

I am a longarmer and it is very hard for the dots to disappear without changing the tension, The LA tension is a pain to keep adjusting. I did it once and never again.

I don't change the thread colors so the bobbin is different,all the colors are the same top and bottom.

I do quilts for cust who entered them in shows and they win ribbons,so the thread being the same color as top and bottom is okay.