Newbie questions; Bolster foam negative material allowance???

[SoInTrouble]

I am doing my first boat project, and it has bolsters.  I have a couple of questions.  I understand you want to have 1/2 inch extra foam on the edges of the foam to tighten up the cushion.  For the bolsters, I have cut and folded the 1" foam around the core and have a bolster core I am happy with.  The circumference measures 22 inches on the top bolster and 17 inches on the bottom bolster.  I want it to look tight and wrinkle free, how much should I shorten the cover over the bolsters?

My second question is; do you sew the entire cover first with the zipper, and then add the bolster pocket piece with the second zipper?  

Thanks.

[kodydog]

Generally when doing cushions, pillows or bolsters I cut and sew the fabric first. Then I shape the foam to fit. Over the years I've learned to get a feel as to how much "push" to add to the foam. In your case I would start with 1" push, side to side, stuff it and see what it looks like. If it looks to tight you can shave some off one end. If it looks to loose around you can add a layer of Dacron. Work with it till you get the look you want. It's not an exact science because different fabrics need different tolerances.


Hope this helps.
Good luck.

I don't understand your second question. More info please.  :)

[baileyuph]

I am doing my first boat project, and it has bolsters.

A description of where these bolsters are located might help.

Are these bolsters in the backrest of a cushion or the bottom cushion?  Sometimes they are at the ends of a seat bottom?  They are part of the seat aren't they?

I will assume they are in a backrest and there are two of them, tubular shape that are horizontal when installed in the seat?  

That might not be the right assumption, but if so, my vision is they are not cylinder, there would be a flat area at the backside, not very visible.  So it would be equivalent to a flat tire, round except where the tire meets the pavement.

In that case, the cylinders shaped as I am assuming could be filled through a zipper opening for each bolster.  Did you have he opportunity of seeing how the original bolsters were configured?  You did take this seat apart?

Whatever; the bolster cover has a length and a diameter.  Therefore the filler, a foam core, in this case you say, should not only be larger in circumference than the cover but longer also.  If this perspective of the issue is good, in general, I wouldn't think that the foam diameter and length should be more than an inch bigger than the cover you make.  Not that much when dealing with foam cores of a higher density.  So, remember that is a variable that one is better able to answer and deal with from experience.  You are not going to be an expert on the first job, no one is an expert that easily.

The smaller bolster you make, being smaller, the core may not need to be oversized as much as the larger bolster, common sense.

Provide a picture of the original, maybe that would help.  Perhaps someone with boat experiece will have a better understanding of your situation?

Doyle

[SoInTrouble]

Generally when doing cushions, pillows or bolsters I cut and sew the fabric first. Then I shape the foam to fit. Over the years I've learned to get a feel as to how much "push" to add to the foam. In your case I would start with 1" push, side to side, stuff it and see what it looks like. If it looks to tight you can shave some off one end. If it looks to loose around you can add a layer of Dacron. Work with it till you get the look you want. It's not an exact science because different fabrics need different tolerances.


Hope this helps.
Good luck.

I don't understand your second question. More info please.  :)

Thanks for the response.  I probably should have filled in some more details.  The bolsters are at the top back of the back bench seat.  There is a sun deck at the back at the top of seat level.  The bolster breaks up the two.  I am asking if the bolster is part of a cushion, what order do you sew the two chambers.  The large one containing the two pieces of foam, then make the separation between them, or do the bolster part, and add the rest of the cushion to the bolster.

[kodydog]

Sometimes those boat cushions are very tricky to reproduce and even harder to describe on a forum like this. I think what you have is a seat cushion and a bolster that acts like a back cushion and the two are connected together.

Different manufacturers produce this type cushion in different ways. When I reupholster a cushion like this I try to take it apart the same way it was put together. Paying close attention to details and taking notes of each step along the way. Then I put it back together the opposite way it was taken apart. It takes some time this way but the results are usually good.

Maybe some of the boat folks have more ideas.

[JuneC]

Is it like this pic (center photo)?
  http://www.boatshop24.com/en/motor-boats/chris-craft-usa-corsair-28-3115527

These don't typically use zippers at all with the bolster and outsides stapled to a board of some sort.  Yours has a soft back that needs a zipper for the internal bolster pull?

June

[DBR1957]

You really need to give us make and model and hopefully a picture. Someone may
actually have experience with the boat you're working on. Until then this is all a
guessing game and no response will answer your question. Worse yet, you might
take advice about something that doesn't apply.

To me "bolster" is a generic term and can apply to many different pieces in a boat.
We need some clarification to better assist you.

[SoInTrouble]

I am doing my first boat project, and it has bolsters.

A description of where these bolsters are located might help.

Are these bolsters in the backrest of a cushion or the bottom cushion?  Sometimes they are at the ends of a seat bottom?  They are part of the seat aren't they?

I will assume they are in a backrest and there are two of them, tubular shape that are horizontal when installed in the seat?  


Doyle

Thanks for the responses; I was away from my computer.
The boat owner fabricated a engine cover/rear seat that is similar to the Chris Craft pictured below.  http://www.boatshop24.com/en/motor-boats/chris-craft-usa-corsair-28-3115527 The bench seat is straight and ends at the side of the boat.  The Bolsters are at the top of the seat, separating the sundeck from the seat back, like on the chris chraft, and at the bottom of the seat behind the knee as you sit, both run from side to side of the boat.  The engine cover and seat open up allowing access to storage.  There are no existing patterns to go from.  Because of the various materials used in fabrication, stapling the bolster is not an option.  The client purchased a huge 25' roll of 6" wide Velcro.  Obviously I will only need a fraction of that, and will be cutting it into strips.  I fabricated the bolsters first, so I would know what I am covering.  I have created one long length of each of the bolsters for the top and bottom.  I will cut them into lengths I need, adding 1" to fill out the cover, I am just not sure how much to reduce the measurement around the bolster for my pattern.