RD350 seat

[cliffrod]

This isn't a huge project but is here to do. A good local friend has an affinity for RD Yamahas. He has been assembling bits to do a cafe project for a while. His part is nearing resolution, so now he's ready for a seat. This is as much about art & display as riding. like many of us, his days of youthful pursuits are now tempered by reality... My Guzzi project is nowhere near done, but I'm still collecting pieces.

He brought the rolling chassis over a couple of days ago so I could start the seat buck.



He had a couple of pics of what he likes, so I made a quick center profile to trim & sand into submission while he was here. Very cool to get to use some of my new to me covid-score wood shop equipment to do model work even faster now.

[cliffrod]

For now, I stapled some cardstock along the edges and then trimmed it to establish a general lower edge profile.



Overhead rear view-



I'll flesh out the balance of the hump next and use some sheet metal to replace the card stock.

He still hasn't settled upon a taillight for the seat. We took a few dimensions and I sent him home to find what he likes & wants before this progresses. He also hasn't worked out the seat mounting arrangement beyond "Oh, I'll do something when we get to that point." I didn't tell him that will likely mean some welding along with a repaint of his just-painted frame. We'll see.

He is planning to have tank and seat professionally painted with OEM stripe kit on tank matched/continued along the seat, so that may be a good way to suggest a similar professional paint job for the frame to supplement his rattle-can low$$ work.

[cliffrod]

A few pics of buck progress. I'm not planning to use this as a hammerform, so am just using clear softwood 2x4 lumber on hand. There's a small discrepancy between left and right on the plywood base, so the larger side was used to determine initial cuts. Pieces were then sanded to match both partners as stacked and opposite sides.

As cut-




Sanded square-







The plumb sides still need to be fully matched, tapered, corners rounded, etc. the individual stacks will be glued up before attaching them to the buck or additional shaping & sanding. We will check it on the bike as well, to see whether he prefers the slightly heavier side before they are sized & matched.

The owner has decided to not include a taillight in this build. This bike is being built for display. It will be fully operational and may see parade duty but not regular road use or vintage racing by him. He's old enough that he has passed that stage in life.....

[Steve Murphy]

Looking good Cliff!

[Chazza]

Nice work Cliffy. I often find just as much enjoyment in making the tools and process, as there is in making the part,

Cheers C

[cliffrod]

Lester brought his bike over for some test fitting and direction regarding what he wanted for shape.


The front hump detail is common to some "proper" cafe builds, including these Yamaha. He would like it to overhang and capture the pinch seam at the rear of the tank. I predicted lots of effort trying to rubber bush everything into position and still will likely have chipped paint. He said, "that's ok. It's what I want."

[cliffrod]

Back to the sanding. The trailing end of the seat was beveled a little more. Front hump was recessed for general reference and then attached to the base with screws.





Just like gesso on a plaster model, a couple of coats of polyurethane will keep the buck clean while handling it and during use where aluminum on hands will quickly gray it. It will also yellow with age to a golden honey color. Having a pretty model is good for oohs and aahhs, especially from a patron's significant others who may not be as supportive of $$$ work without it.






After most shaping & sanding was finished and before the polyurethane, the two sides of the rear hump were glued to the central profile element and then reattached to the base with screws. This seat pan pattern will obviously fit an RD350. Having the buck as a modular pattern for reference will allow this hump to be easily used on a different seat base or to remove/install different detail on this base. It's all about capturing information whenever you have the chance.



Having models in inventory makes a big difference in how competitive you can be when quoting work. It also helps convey what you can do and have done to patrons who can imagine but not actually "see" shapes like people who make them. Saying "what I can do" matters less to many people than showing them "what I have done." Seeing a model in person and a picture of an accurate replication of that model closes sales. Having a wall full of sold and used models is one of the best portfolios and advertisements that a craftsman can have, even if it takes years to accrue. Over the long term, making a pattern/buck/model for most jobs makes sense.

He's still thinking about how he wants to install the seat on the frame, which I would rather figure out before proceeding. He's not worried and says "it shouldn't be a any problem.." Time to start the metal work, but not sure that much will happen until after the holidays later next week.

[Peter Tommasini]

Doing well there Cliff , nice one ! .......Please post pics during progress
Peter

[Blue62]

Nice Cliff
Looking forward to your progress on the metal work.

[cliffrod]

Thanks, guys. Free time is a little sporadic but I spent Saturday afternoon starting the metal work. Sunday I worked on my lathe r&r, getting it closer to operational.

I'm not certain that this is the best approach. We'll see. Doing the rear hump in three pieces is practice for my pending Guzzi tank, both in terms of shaping and welding. Adding the front hump to the seat pan will still require another piece across the front to close and support the pan in use. Until the actual mounting arrangement is better sorted, that detail is not as critical. He likes the false wire edge I did on my first (practice) Guzzi seat, so material + extra has been left for that.

I made paper patterns and cut blanks which are still oversized.





I didn't get many pics yet of the base/pan. The front and rear detail were both bent to match the buck. The flange was started. Fit is ok but needing more work. With the long depth to edge, we'll see. It may be better to weld on the flange but I wanted to try it like this first. This seat will be painted, not polished. Still, I want it to be well-surfaced. The front hump was bent and is close to fitting the buck. A little more and it should be a great fit. Some of the extra material is present because I'm trying to decide where weld seams will be. Turning flanges to hide some welds under upholstery is my current plan, in order to help make the painted surfaces better faster. I'm concerned about welding along the corner joints and producing/maintaining excellent corners or edges for paint.


This has base sitting high above the buck. Too much extra material now to easily justify the two pieces together.



I got this sheet from a shop RockHillWill likes a lot. It was the end of their inventory at the time and they weren't sure if it's 3003 or 5000 series .063. It seems harder to work, so I'm guessing it's not 3003... I used it for the peach leaf armature but that was a more casual shape. The scrap I used for the Guzzi seat and fender seemed a lot easier to work. If I need to redo it, I've got a new sheet of 3003 to use.

No matter- Holiday plans means it will be at least another week before there's more shop time.

[cliffrod]

Well, like others here have mentioned lately, there's nothing like getting older to be reminded of things from the past. After 20 yrs of stone work, my right shoulder isn't great. But a chest injury that predates my stone work has become a bigger issue. Getting a vigorous start on the seat several wks ago meant the next day, then next several wks, were needed before I could do more hammer work. So I've spent the down time mounting my arbor press, planishing hammer and shrinker on floor stands to help ease the work when possible. Today I decided things had finally healed enough to do some more metal work.

The bike frame has a nice flow, minor reverse. I wanted to try to fold the sides down from the larger seat pan, even though I doubted I could produce that reverse along the 90 degree fold and still have a long flange to ultimately finish along the bottom with a false wire edge. I was right. it wasn't working. So the turned-down sides were cut off.



The seat pan was then trimmed to match the front and rear humps and I turned a flange at the rear of the front hump. The seat will be painted, but I still figured it best to locate the welds under the upholstery.





Fit to the buck is pretty good.

[cliffrod]

I cut two new pieces for the sides and folded a flange in my small (free) chinese brake that was part of the covid bounty this spring.



Then I used a combination of shrinking and stretching on the horizontal flange to produce the nice flow I was seeking. A simple cardboard pattern of the curve was easy to match.



The vertical sides are perfect, still under plastic. Much better strategy.



Later, the horizontal flange will be trimmed to again place the weld under the upholstery. Pretty happy with the change in strategy. Next is shaping the pieces for the rear hump.

[Chazza]

Nice to see progress Cliffy. Good luck with the aches and pains.

PS photo of the FSP please 😋

[cliffrod]

I'll got some tape around here somewheres....

[neilb]

nice progress cliffy

obviously looking at what you are doing from an outsiders perspective, you could have created an infill block of wood so you could clamp it where the seat dips in. then you could have hammered the flanges over as you wanted to

thank you for posting your progress

[cliffrod]

nice progress cliffy

obviously looking at what you are doing from an outsiders perspective, you could have created an infill block of wood so you could clamp it where the seat dips in. then you could have hammered the flanges over as you wanted to

thank you for posting your progress

I thought about doing an actual hammerform or hammerform areas. Instead, I wanted to see if I could form it without them.

This seat will be painted and I am concerned with the exposed transition corners. I want them to be more radiused than square/sharp. The goal is to make this seat look more factory oem than custom built. That's the reason I didnt want to weld along the corners and then try to make those 90 degree edges pretty enough for paint. The final visible vertical flange along edge of the seat will be finished with a false wire edge. Hammerforming that flange into proper orientation & shape, then smoothing everything up, then trying to do the wire edge didn't seem practical compared to making the portion separately and welding it. Wanted to try it but expected it wouldn't work, at least for me at this point. Maybe later I'll be able to do things like that. Making the flange like this only took a few minutes and both the visible portion & transition corner are excellent.

As far as welding the parts into place- will how the horizontal flange & the seat pan are trimmed to match each other impact any movement when welding? Should the flange be trimmed so that the remaining flange edge is parallel to the shape of the transition corner to help maintain that shape or will it not matter to trim it in a straight line? I don't want to lose some of the shape when its welded together.