I think we're both headed the same place thru different means.

Just added the third layer.

I've got about 1/2" minimum foam thickness where the cutouts are and about 3/4" everywhere else. I may head out later and get a real low density foam batting just to help even out my poor shaping skills.

Drying in the sun...

 

looks good, keen to see how it turns out.

FYI, the embossing you did probably won't last long, the leather your using is quite soft and will return to its former state.

If you want to emboss it with a lasting imprint, you need to heat the boss first to about 50 - 60 degrees C, press it and leave it under pressure for about 3 or 4 minutes. The heat will break down and collapse the protein chains in the leather and stop it fully returning to its natural state.

recommend practising on some scraps first.

 

I didn't use any heat but I did soak the leather in water, then used some thick paper towels for platens top and bottom (under the leather and over the embossing plate), then put the stack between two 1\2" steel plates, THEN applied full pressure with my hydraulic press (6 ton?) and let it sit under pressure until dry. A day or two.

It's been stiff and well defined for a couple months now. Regardless, it's just contrast for the medallion so if it relaxes some it's no big deal. Gotta get your face right up on it to even see that it's embossed under that medallion.

 

Oh cool, was gonna also suggest leaving under pressure for about 48 hours.

 

You seem to have a lot experience in this arena. I have a question about my next step...

I've got some very thin batting (80\20 quilt batting, about 1/8" th'k, uncompressed.) that I intend to lightly adhere to the back side of the leather after stitching. I was then going to lightly stretch the cover over the assembled seat pan, using contact cement and rivets only on the underside. About a 1" margin around the entire outside perimeter.

That sound OK? I was torn about whether or not to use cement on the seating area.

 

I do have a lot of experience, up until a year ago Handmade leather for bikes was my biz. Had to shut it down due to the building I was in being demolished and unable to find an affordable new location in time. Hoping to kick off again in the coming months if things pan out, anyway enough of the beer talk...

You could do as you mentioned if you are recovering a couch, or never intend to ride in the rain.

Use a spray adhesive (contact or similar) to glue the batting to the top layer of seat foam. You might wanna think about doubling it up if its only 1/8 of inch.

Over the batting you need to put a waterproof layer, otherwise you will get water in the foam and it will never dry out completely, and eventually rot out the foam or cause your glued layers to separate.
The water proof layer needs to be robust, your *** will be punishing it for many thousands of miles, so use a heavy duty, yet pliable plastic. A poor mans solution Ive seen work well is 4 to 5 layers of the heavy duty cling wrap.
Do not stretch the waterproof layer over everything, you'll just compress your batting and the additional stress may cause the waterproof layer to tear after X miles of being *** bashed. Just drape it over so its flat, but not tight.

Fastening the seat cover to the Pan: 1st, give your self about 2 inches to work with, you can trim it later. Don't use contact cement, it just doesn't last, has almost no moisture sealing properties, and will actually melt on a hot day. Since you are fastening leather to Steel, I would certainly rivet, and instead of Contact I've used Mastic, the stuff they seal car windscreens with. Apply it as a thin bead as you rivet as it has no holding strength until after its cured.

just a note about the leather you're using, its nice stuff, soft and comfy, you won't slide around on it so much,......and its very willing to absorb a lot of moisture. Make sure you use a lot of Natural Oil based barrier style product on it often.

 

Thank you! I truly appreciate the advice and opinions. This is my first ever attempt at this kind of thing. I've done some basic home and auto upholstery work but that was pre-assembled seat covers or fabric. Much less involved.

Water exposure will be extremely limited. I have no fenders, header wrap, breather bolts, and open filter element so I avoid water like the plague. This bike is a fair weather toy, not transportation. Rain does sometimes happen without warning, though.

With that in mind, I did choose closed cell neoprene foam and Barge cement. Both are supposed to be strong and "water proof". I know there is no such thing, but I at least tried to keep it in mind.

I have visqueen sheets, maybe 5mil thick, I can use tho. I never thought of that.

I'm trying to keep the seat as slim as possible without being completely unbearable. I only wanted the batting to help camoflauge my mediocre foam work.

Anyway, moral of the story is that I'm OK to keep the leather unsecured in the seating area and I should adhere the batting to the foam?

Oh, I did pick some leather protectant from Tandy. Aussie something, I think... I left it at home. It has beeswax in it and the clerk said it was amazing.


Foam complete. Gonna start pattern making later today.

 

Better to have the batting secured to the foam rather than the leather. This allows the leather to move around a bit without the batting getting all bunched up in one place.

Aussie leather conditioner, it is really good stuff. Don't be afraid to use plenty of it.

 

Excellent. Thanks!

 

Ě forgot to mention, the tools you have for making your sewing holes are actually for leather lace, not thread. They will do but your holes will be oversized and could cause issues down the road.

You need a diamond stitching Awl and an over stitcher to mark your where your holes will be. More work involved but more rugged and a way better finish.