# Foam To Foam Bond For Turning?

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#### dixontj93060

##### Well-Known Member
Just to qualify, dhbarr mentioned 3M 78 in post #2, which is probably best for your application (see note link below). Personally I have just used 3M 90 before as I have it in the shop and it worked fine. I also keep 3M 77 in my shop, but it's reapplication qualities made it too weak for foam board use.

https://multimedia.3m.com/mws/media/765001O/iatd-product-info.pdf

#### cavecentral

##### Well-Known Member
I've used gorilla glue, but it is a harder material than the foam. Also, no clue what glues will not effect your hot wire cutting. I used a lathe hand turned with a trim router cutting the foam (total mess of pink confetti to clean up after).

#### mkadams001

##### Well-Known Member
Since you are getting a lot of recommendations maybe tell us what type of foam you are using.

There are a lot of good recommendations here.

If you are using a urethane foam which would be closed cell you will need an adhesive that does not require air to dry. I have used a lot of 10 to 18 lb foam boards and use epoxy or gorilla glue with good results.

Spray 90 should would ok on denser foams but I would not use spray 77 because it is better suited for paper and such. If you are going the contact cement route then I think any contact adhesive would work (yellow in the can stuff, 3M or equal)

#### TopRamen

##### SA-5
I guess I did'nt think about the way the hot wire cutter would encounter the adhesive yet, so that is a good point Kevin.

I'm using the blue Dow brand insulation foam, and will be for the foreseeable future, as I can get as much of it as I like for free in these already cut sizes:

#### TopRamen

##### SA-5
Here's the video that I watched that had me thinking about the Glidden Gripper, but that would likely be fairly thick for the hot wire to go through.

This lady is not turning the foam, just carving it, so I can see why she likes the Glidden product, and why it is probably in retrospect, not ideal for this application.

[video=youtube;rnOegaOKu38]https://www.youtube.com/watch?v=rnOegaOKu38[/video]

#### mkadams001

##### Well-Known Member
I think that is an extruded polystyrene. I think post #2 has the best choices.

#### rstaff3

##### Oddroc-eteer
On the only big cone I did, I used some type of polyurethane glue. If whatever you use is expanding, make sure to compress the stack well while it sets. Also, I found that the discontinuities of the denser material tended to cause ridges at the joints. They compress slightly and it is easy to take the surrounding foam faster than the glue. I ended up cutting the ridges out and back filling them with Fill'n'Finish before lamination. This may be handled better with extra practice or a faster lathe, but I only planned on doing the one big cone!

#### Micromeister

##### Micro Craftman/ClusterNut
really not sure how big a cone your trying to turn.
Biggest SM Styrofoam cone I've done is BT-101 (3.9"). That was glued up with 3M 77 spray adhesive.

I've also turned a lot of High density foam board 18 to 22lb/cu ft. These 1 and 1-1/2" thick pieces are joined with Polyurethane glue clamped well all around as the stuff expands a great deal. the biggest cone done that way was BT-80, most however are smaller BT-70 & below.

#### TopRamen

##### SA-5
really not sure how big a cone your trying to turn.
Biggest SM Styrofoam cone I've done is BT-101 (3.9"). That was glued up with 3M 77 spray adhesive.

I've also turned a lot of High density foam board 18 to 22lb/cu ft. These 1 and 1-1/2" thick pieces are joined with Polyurethane glue clamped well all around as the stuff expands a great deal. the biggest cone done that way was BT-80, most however are smaller BT-70 & below.
I've been working with 3M77 and Elmer's Spray Adhesive from the dollar store for a month now.
The 3M never really dries on the Blue Foam, whereas the Elmer's offers the Permanent Bond option in it's instructions. I used both when building the steps for my dog to use to get in and out of the car. It was not going to matter on the final product, as it was covered in wall repair FG, then filled with expanding foam before being papered and sprayed with flexible sealant, but during the build of the skeleton of the structure, the wait 3-5 seconds then bond immediately for permanent adhesion of the Elmer's held up much better to my walking up and down on. Both make no difference when cutting with the hot wire cutter, and since the foam cones get a skin anyhow, it likely does not matter incredibly much, but I prefer the Elmer's for now, even though I get the 3M at the hardware store I used to work at with a discount, so price is not a deciding factor in my case, only performance and ease of use.
I don't want to stand there waiting 30-40 second poking at it with my glove knuckle to test for tackiness, especially if I know it is never going to cure fully anyhow.
I have not tried the 3M 90, and will do so when I get around to it, but it's a wonder I remembered to come update this thread.
I was also making structures of various aspects for my yard from blue foam, and again, I would got out the next day and have to press everything done with the 77 back together, so I simply put that project on hold.
The tiny cans of Elmer's are not well suited to building a shed for example.
I used a half gallon of TBII on foam with the double glueing method and got very durable results, but that's not ideal for nosecones or stuff that's going on the lathe.
I'll report back to this thread after I try the 3M 90 product.

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#### Micromeister

##### Micro Craftman/ClusterNut
I saw a video that says Glidden Gripper Primer is the best thing, but when I found Glidden Gripper on Amazon, it was \$101 a gallon.:y:

What are you folks using to glue high density foam together for turning cones and such?

I already have an idea that JB Weld and JB Kwik will work great, but not if I need volume.
High density Foam, Sign Foam, and other brands are expaned Polyurethane foam. To bond these materails the "Best" glue is a Polyurethane Glue. Such as Gorilla Glue or Elemers Ulitmate Polyurethane glue. Do note; both are water activated Expanding glues that must be tightly clamped to ensure they do not misalign the parts as they cure.

SM type Closed Cell Styrofoam on the other hand is an expanded Polystyrene, which takes another advesive altogether.

If you are really interested in what glues or adhesives work with which materials, especially all the various Plastics (polyurethane foam is a plastic) you might want to take a look at Tech Tip-017 "Working with Plastics" over on the www.narhams.org website in the library section from the left hand menu. It's a 12pg in depth look at what sticks to what and what doesn't There is also a seperate Photos add-on file that might also be of help.
Working as the chief Purchasing agent for a Large Custom Sign Company using all kinds of different plastics and other material I had to research and find the "best" possible sources for bonding adhesiveds and glues. Tech Tip-017 is an end result of many of those searches.

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#### TopRamen

##### SA-5
Thanks John!
Will do!

I made a plug for a mold today out of expanding foam using a payload bay template, some paper CR's punched with holes made in OR, a BT-5 stripped body tube, nose block and nose cone, teflon tape, and a BT-55 conical to hold it while I foamed it.
It's too bad I had the gloves, respirator and goggles on for the outdoor process, as I did not get pic's of it, but it seems to have worked out very nicely for a first go, and if the plug turns out well, I'll end up with a mold for BT-60 conicals.
The tip was frustrating me about getting perfect, so I decided to see if the process I envisioned was even valid by simply deciding to chop it off and go through with it for proof of concept.
If I decide that it should be a flying nose cone rather than a plug to make molded parts, I can remove the wooden dowel if need be by cutting the exposed portion of BT-5 hanging out of the shoulder, as I was careflu to only have the dowel held in with a little of the foam.
That way if the cone is for flying, I can take advantage of the hollow body tube core up to the point of the upper most CR that is sized around a BT-5 nose block from BMS, or even if I had to, drill through that balsa to the upper hollow under the BT-5 cone.
I just used a few tows of CF that were roughed up and CA'd to the Balsa at the tip to give me a rigid surface to press into a bearing if I need to chuck in in the drill to rough sand it, as my lathe is still "Almost Ready". If it was finished, I would not have tried this experiment, and I'm glad I did, as I learned a lot, and this is a very light cone even with the dowel still in it.
I used Crown 3470 spray mold release inside the BT-55 plastic cone to make sure I could get the two apart, and it worked well.

I was pleasantly surprised to see how well it fit a BT-60 after just some quick clean up with sandpaper and then some very gentle touches of an acetone soaked Q-tip. Some factory plastic/balsa or glass cones don't even fit this nice, but that's understandable as they have to make thousands of them, so they cannot pay attention to detail for each one.

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#### Viking

##### Well-Known Member
...
SM type Closed Cell Styrofoam on the other hand is an expanded PVC, which takes another advesive altogether
....
Actually, SM Styrofoam is XPS or eXtruded Poly-Styrene.

For EPS/XPS foam, I've had plenty of success for years with simple adhesives like PVA (PolyVinyl Acetate. 'White Glue', not the Alcohol mold-release type PVA ) or where water resistance is needed, 30-min epoxy.
For both, I use a squeegee to apply spread a very thin even coat on both surfaces, then just mate the surfaces and weigh down.
Both adhesives make joints that are stronger than the parent material = win.

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#### TopRamen

##### SA-5
Actually, SM Styrofoam is XPS or eXtruded Poly-Styrene.

For EPS/XPS foam, I've had plenty of success for years with simple adhesives like PVA (PolyVinyl Acetate. 'White Glue', not the Alcohol mold-release type PVA ) or where water resistance is needed, 30-min epoxy.
For both, I use a squeegee to apply spread a very thin even coat on both surfaces, then just mate the surfaces and weigh down.
Both adhesives make joints that are stronger than the parent material = win.

I've heard of those methods in some of the information and videos I've watched, and while I have no problem trying white glue for this, since it is cheap, even by the gallon, I'de hate to use pretty much any epoxy just to slap a stack of blue foam together.
Growing frustrated with my progress on my 3/8" spindle lathe, tonight I put together the parts for a half inch shaft lathe, that will atleast get me turning cones while I finish the overly complicated mess I've got myself into what with wanting to make it collapsible and easily stored when not in use, and the guides for the hot wire are not really necessary just to make some LPR practice cones and whatsits. I can even take this set up and simply chuck the 3/8" spindle into it, rather than wait to find the right belt for my other motor and the 2 shaft collars I'm missing, but this motor is overkill for nearly anything, as it was supposed to be the replacement for my free standing drill press which has been out of commission for nearly two years.
Anyhow, atleast I'll be spinning things tomorrow/today, even if they be spinning at unheard of velocities. I can do some LPR wood cone in lightweight woods and even some MMX stuff, as I've been turning those for the past few months on a regular old Black and Decker from the 70's and they come out ok. This will let me have both hands free and not have to worry about overheating anything, as this Craftsman motor has overload protection.
I'll have to figure our if it is safe to use a dimmer switch with it to slow it down as I only have a few pulleys to fit it, and I don't want to start cannibalizing my Drill Press, which is very nice IMO and from the late 30's-early 40's if I remember last time I looked it up.

This rig just needs a different piece of wood to mount it on that is out in the shed, and a pillow block to hold the bearing I put on the right hand shaft that has the chuck on it now. The plate needs some teeth, then I can screw that on there too as an option since that is right hand threaded too, and from a lathe I had a long time ago for making small gun parts like trigger assembly retention pins and such, where the pin is typically held captive by a torsion spring or such, and needed be as precise or tempered as properly as stuff like firing pins and what have you. The white thing is just a cover I made for the wire wheel, so I can turn the shaft by hand when powered down and not have to wear a glove. Keeping the wire brush wheel would unbalance it, but having it be free spinning doing what wire wheels are intended to do while my attentions are focused on my workpiece is not a safe option. I'll wear eye pro anyhow, but why risk anything with my luck.
In the morning, I'll hit the white plastic with heat and conform it around the wheel. I'm just done messin' with it for tonight.

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#### Micromeister

##### Micro Craftman/ClusterNut
Actually, SM Styrofoam is XPS or eXtruded Poly-Styrene.

For EPS/XPS foam, I've had plenty of success for years with simple adhesives like PVA (PolyVinyl Acetate. 'White Glue', not the Alcohol mold-release type PVA ) or where water resistance is needed, 30-min epoxy.
For both, I use a squeegee to apply spread a very thin even coat on both surfaces, then just mate the surfaces and weigh down.
Both adhesives make joints that are stronger than the parent material = win.
You are correct, my bad...SM Styrofoam is expanded Polystyrene not PVC. slip of the typewriter
That said however; depending on the size of the SM Styrofoam the OP is using, white glue alone in any from is NOT the recommended adhesive. This is especially true of anything that is going to be high speed lathe turned.
For most Lathe turning I've found using a 3/8" or 1/2" hardwood dowel center with either 5 or 30minute epoxy in a thin layers as mentioned in your post above allows accurate turning without fear of the object flying apart.

Top: if you are using a base back plate as shown laying on your table, a scrap piece of thin (1/4" or 3/8") Plywood makes a great way to mount the foam blank. I still use a 3/8" dowel through the middle on large cones to give the Live to dead tail center something to bear on.

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#### TopRamen

##### SA-5
You are correct, my bad...SM Styrofoam is expanded Polystyrene not PVC. slip of the typewriter
That said however; depending on the size of the SM Styrofoam the OP is using, white glue alone in any from is NOT the recommended adhesive. This is especially true of anything that is going to be high speed lathe turned.
For most Lathe turning I've found using a 3/8" or 1/2" hardwood dowel center with either 5 or 30minute epoxy in a thin layers as mentioned in your post above allows accurate turning without fear of the object flying apart.

Top: if you are using a base back plate as shown laying on your table, a scrap piece of thin (1/4" or 3/8") Plywood makes a great way to mount the foam blank. I still use a 3/8" dowel through the middle on large cones to give the Live to dead tail center something to bear on.

Thanks for the tips, and I will try them.

Here's the video of me turning on the lathe to watch it spin. That's as far as I made it today, but I might be able to make something with it tomorrow.

https://www.youtube.com/watch?v=v5xgqUitNcc&feature=youtu.be

Oh, and the first cone I'm doing is going to use the Elmer's Spray, as I have full confidence in it.

I'm going to make a custom holding chuck for it using paper templates, fiberglass and carbon fiber, but for now it will just be foam on a spindle.

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#### Micromeister

##### Micro Craftman/ClusterNut
Thanks for the tips, and I will try them.

Oh, and the first cone I'm doing is going to use the Elmer's Spray, as I have full confidence in it.

I'm going to make a custom holding chuck for it using paper templates, fiberglass and carbon fiber, but for now it will just be foam on a spindle.
Pretty nifty use of an old tool box Top!
Are you using the tool box side as your tool rest? I'm not quite seeing where your foam or wood is going to be mounted, on the metal rod inside the box?

Not sure if you have ever turned anything on a lathe or not so I'll just make an assumption here;
Accurate turning requires the use of a cutting tool rest to ensure correct alignment with the material being turned and the cutting tool, file, rasp, or sanding block being applied to the material. Without a tool rest of some kind the very best turning will most certainly be Out-of-Round to totally unuseable.

Your tool rest does not have to be attached permanently to the Lathe (thou it is a good idea to do so if the rest is long enough to support tools and stiff enough not to allow flexing.) That said: any stationary tool rest can be used. The major thing is that it can be locked into a position where the turning can be most effectively be addressed with the various tools needed to shape and smooth the part. Over the years I've made a number of Tool Rests to be used with either one of my 4 lathes or for some nose cones mounted to my Drill Press stand. Most Rests are no more then 6" long to eliminate flexing, Longer need to be made of very stout material making the upper angle (where the tool acutally rests) harder to make.
Hope this make some sense. Below are two photos of a fairly simple rest made for a SCRAP Wood lathe the club had me design so our members could make their own with simple hand tools and an old 1/2" drill or electric motor. Please note that this tool rest is indepentent of the Lathe on which is used. The rest is C-Clamped in place where needed, while being moveable to cover the entire lenth of the lathe turnable area.

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#### astrojase

##### Loves rockets...
During our full-scale V2 build (lots of foam) we were using a product called Liquid Nails by Selleys, to glue the foam inserts etc... the water-based version which worked quite well...

Then we discovered that the aerosol expanding foam works really well too - sticky as all hell, and it is foam so once cured it sands almost as easy as the foam you are using it on...again, made by Selleys called 'Space Invader' and water based. Parfix is another brand but make sure you get the water based version. Spray it on, let it expand a little, then compress the join and wipe off any excess as you go...

So, use foam to glue foam

#### TopRamen

##### SA-5
Pretty nifty use of an old tool box Top!
Are you using the tool box side as your tool rest? I'm not quite seeing where your foam or wood is going to be mounted, on the metal rod inside the box?

Not sure if you have ever turned anything on a lathe or not so I'll just make an assumption here;
Accurate turning requires the use of a cutting tool rest to ensure correct alignment with the material being turned and the cutting tool, file, rasp, or sanding block being applied to the material. Without a tool rest of some kind the very best turning will most certainly be Out-of-Round to totally unuseable.

Your tool rest does not have to be attached permanently to the Lathe (thou it is a good idea to do so if the rest is long enough to support tools and stiff enough not to allow flexing.) That said: any stationary tool rest can be used. The major thing is that it can be locked into a position where the turning can be most effectively be addressed with the various tools needed to shape and smooth the part. Over the years I've made a number of Tool Rests to be used with either one of my 4 lathes or for some nose cones mounted to my Drill Press stand. Most Rests are no more then 6" long to eliminate flexing, Longer need to be made of very stout material making the upper angle (where the tool acutally rests) harder to make.
Hope this make some sense. Below are two photos of a fairly simple rest made for a SCRAP Wood lathe the club had me design so our members could make their own with simple hand tools and an old 1/2" drill or electric motor. Please note that this tool rest is indepentent of the Lathe on which is used. The rest is C-Clamped in place where needed, while being moveable to cover the entire lenth of the lathe turnable area.

I used to have a metal lathe, so yeah, I get the finer points of lathing, but this is just for making foam cones, that will be glassed and then sanded to specification. and for other things, but I get what you are saying.

I might have mentioned it, but if not, I'll mention it again. There will be guides on either side of the spindle, to use a hot wire to cut the foam to approximate shape and size. These same guides will then be my tool rest for sanding.
I stole the Idea from the I can't remember right now folks that I mentioned earlier.

Here's a foamy mock up to illustrate:

I have not made the locks for the hinged parts of the box yet, nor the mounts for placing the guide templates(Tool Rests) in, so the little bit of turning I did today was freehand just to see if the motor had enough power, which it did'nt.
I got a new motor test fit and even ran for a few seconds today, but then it got dark, so I'll mount that up tomorrow.

Oh, and the Elmer's spray works just fine, but I have spray foam too and some other stuff, but I see no reason cost wise to worry about using anything else right now.

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#### TopRamen

##### SA-5
SpeedMotionRockets are the folks I got the Idea from, but their website won't load, so I can't show you there lathe in action.
It is much larger, but uses the process that I'm going to use.

#### TopRamen

##### SA-5
Still did not get my guide brackets made, but I did get it rebuilt today and running.
I trust myself to freehand a couple before being anal about exact dimensions.
It's not like I'm making stuff to sell, or am going to ever run out of free blue foam.

[video=youtube;9nwZHdVUCX0]https://www.youtube.com/watch?v=9nwZHdVUCX0[/video]

#### TopRamen

##### SA-5
Lathe 2017 sneak peek:

This one will handle metal and wood, so I will certainly knock out a few nose cones while I'm at it. Built as a real lathe with real machine parts, I will use it first to build it's bigger sister, which I will use to make a milling head for my first homemade milling machine.
I have acquired the requisite skills and advice in these matters through the necessity of having to acquire so much vintage machinery to fix my home.
I hope to be able to get back to rockets, working in my new actual workshop by the end of this year.
Life is so much easier with pulleys, belts and motor being hooked to everything that does what I used to have to do by hand.

#### TopRamen

##### SA-5
I've got a real lathe now, along with the one I'm building, and though it is an old Shopsmith, it would not even notice if you were turning foam with it, as it can do wood pretty good.
It needs a little work and modification, but these are the things I've been doing and getting good at for the time I've been absent from rocketry.
When I have time to start building rockets again, I've got so many new skills and manufacturing technologies that I can really build some cool stuff.
One fellow is holding a Gorton Pantograph engraving machine for me, since he has room for it, and you could do some really incredible detail work on foam with something like that, even though it is meant for metal. I'm also trying to learn pattern making for casting work.
I need to clean this thing up and fit my mods, but a nicer one is being lent to me by a guy up the road, as he no longer uses his or maybe never used it. I have to go get it next week sometime, as he is busy this weekend.

#### TopRamen

##### SA-5
I'm well on my way now, but in order to properly run and maintain a lathe, it needs to be set up level on a solid surface, like most other machines, and so I am building a real shop for these things so as to have my house back finally.
the Shopsmith goes well, and I've applied the "Primer/Bondo Spot and Glazing Putty, repeat ad nauseum" to the Aluminum castings with wonderful results so far.
Yes, I' am going to glass it and CF it for the heck of it. The surface finish of the casting would not allow for a good bond of the glass if I did not fill the imperfections, so most of the primer and Bondo will get scrubbed away before composite cloths are applied, but I filled everything as best I could with JB weld and sanded that smooth first, but you can only use so much JB weld on something this size before you realize you can get away with smoothing out the remaining spots with primer and putty. In the very end, I'm even going to paint over the CF, so all the work will be hidden anyhow, but it will be a wonderfully rigid and enjoyable thing to have.
One of the coolest parts is that just like you folks here on the Rocketry forum have supported my efforts to learn and try new thing through sending me stuff to work with, folks in the machining forums also are very gracious and kind, so I now have a free compound to use on my frankenlathe, along with various carbide and HSS tooling. The configuration of the SS makes it easy to make a template jig for, and so for tiny metal things and larger lightweight things like foam, it will take on all comers.

I swapped a free 3/4" hollow chisel mortising bit for a dial indicator, so I can get the spindle tuned up and if necessary replace the bearings, to get as little as two thou of run-out, thanks to things I have learned. That was on a stock frame however, that someone added an extra bearing to. My frame will weigh twice as much, and feature enhancements, so I stand a chance of having a particularly fun piece of equipment to work with. I'm also shortening the ways of the machine and mounting it to a table extension of a sliding tablesaw, so it will weigh in considerably more than any hacked Shopsmith I have yet to come across in my research. By the time I am done, I will likely have other lathes, but this one is my learning lathe, so it will be just fine if it is not as perfect as can be for my purposes. Five or ten years from now I'll be able to scratch build a lathe that will rival the best, but in order to build a lathe you need a lathe first.

#### TopRamen

##### SA-5
Hooray, a functional shopsmith at last, with parts to spare thanks to the first one. This one was even free.
Two headstocks are better than one.