Perhaps a larger needle? Could be getting deflected on the thicker stuff

Of course first look for mechanical things, sometimes the heel of the pedal could bottom out on the cross bar before returning to the full rest position. Sometimes the return spring is wimpy, solution is to stick a bit of scrap foam under the pedal to assist. Return spring has extra notches on the c...

Outstanding!

For pleats or diamonds, like you mentioned, i'll mark it out and sew the perimeter at 1/4inch before cutting. Then my 3/8 construction seam hides it. Never found the need for more than that

Our apprentice went last spring and had really good things to say. In addition to the sewing and patterning techniques, they covered installing, estimating and billing. It's expensive, but you'll otherwise learn these lessons the hard way costing you time and likely material too. If you can swallow ...

Make him sign a waiver if you choose to do it. There are leathers that can be used for boat cabins. Whether that is what he has, who knows. Likewise, there are some leathers that shouldn't be used in a boat. Find out exactly what he has, oil tan, vag tan, etc., and go from there

And spray your blades with a silicone spray lubricant. It's amazing how much it helps and won't hurt the foam

This is how i do it. Once you do your math and find the angle, mark the foam. I use the table edge as a lower guide and the mark on top as an upper guide. Keeping the saw foot in level contact with the table lip as i cut if that makes sense. https://i.imgur.com/m3IGlit.jpeg https://i.imgur.com/gzi59...

A picture of the bobbin case area and the hook drive gears will tell me a lot

Look for a triple feed machine. Reverse is nice but don't discount machines that dont have it; if it checks your other boxes. Look at the paint. Always going to be scissor rash and a bit of paint missing on the bed of an older machine, but if most or all of the paint is gone from the bed indicates h...

I like the clear. It'll appear white when sewn on white material and blends better with other colors in my opinion.

Not much to do but oil it up and give it a go. If it moves freely and makes a good stitch then you're good to go. Don't worry about adjusting anything but thread tensions unless you figure out you need to. I'd start out with T90 thread and a size 20 needle.

Just gotta roll, cram and fight it through. I always split my piece from table cutout to the edge (usually aft) so it can be installed/removed while the table is in place. Splitting it helps with fighting it through. @BigRig, i like sunbrella acrylic braid for binding vinyl flooring. It takes tight ...

Tried the melting method and it works just fine but snipping a piece of 3/4 binding folded over the teeth and just sewn in with the zipper is more efficient time wise. #10 zipper stops aren't difficult to put on, i use a pair of curved needle nose pliers and they do a fine job.

Something like this perhaps?

Triple check thread path and make sure you're not resting your knee on the knee lifter

You have a spring in the bobbin case to control backlash. Bobbins without the cardboard could easily hang up on that spring. The cardboard eliminates that but if perhaps it is the wrong size bobbin, you'll get slop in the bobbin case which could potentially cause an issue. Bobbin tension is differen...

The servo's with a knob have brushes. You'd need a brushless servo in order to add needle positioning. I'd second fibersport's suggestion of looking at speed reducers. Pretty easy add on to your setup and slows it down a bunch.

Here is an example of what a brand new programmable machine does.


A cam driven machine needs a different cam for each one

If it's cam driven, make sure it's already set up for the stitch you want to make. Or at least having the correct one with it. They're all digital nowadays, finding cams could prove difficult