Category: Bath Tub Shower Sink Surface Repair


TO: Multi-Tech Products

What would cause this wrinkling during a repair?   (see photo below)

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Thanks,
Ryan

To: Ryan

I could give a more specific answer if you had provided more information. Were you using our MMA system, or the Quick Glaze process? What filler was used? What steps did you take prior to seeing the wrinkling? Did you follow our procedures?

So, I will try to explain all of the potential causes. If you were using the Quick Glaze system, it could occur during the spraying operation.

The Base Coat is first sprayed on the surface, and it contains a hardener that cures the coating. The Clear Coat needs to be applied before the Base Coat is completely cured. Otherwise, the solvents in the Clear Coat will attack the Base Coat, and it can create the wrinkling. The Clear Coat can go on directly over the color. The Finishing solvent can also be sprayed directly on to these coatings.. All of the coatings should be applied consecutively, as quickly as possible. Under normal ambient temperatures, the time window is about 45 minutes. Higher temperatures will reduce this working time. Waiting 45 minutes or longer to apply the Clear Coat will make the Color coatings wrinkle. The retarder must also be used as the reducer for the base color coat for thinning. Against all of our recommendations, some people fail to use the QG Clear Coat. If there is no clear coat on the application, you will need to remove the color by sanding and applying a lacquer thinner to remove all of the coatings before re-applying them, correctly..

These issues do not exist with the MMA system. Furthermore, the operating time windows on applying the various MMA coatings are very flexible

However, the MMA System or the Quick Glaze system can lift or wrinkle a previously sprayed repair. For example, it can occur when an epoxy or other unknown coating was used as the base color spray. However, both systems can work well as a touch up of a complete refinish job unless the refinish coating that was used was an epoxy, or there was no clear coat used..

A less common cause is something wrinkled under the color and the clear coats. It could have been the filler, or you sprayed over uncured resin in the FRP shell? If it is uncured resin with this level of wrinkling, the area would be soft when poked with a screw driver or sharp tool.

Hope this helps.

Rob

 

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To:  Multi-Tech Products

The pedestal base on my vitreous china bathroom lavatory is broken into two pieces.  Do you have a product that I can use to glue them together?

Thanks,

Tom

 

To: Tom

Yes, you can use our Poly-Filler to glue vitreous china together.  You will need to prepare the surfaces to be joined by sanding with 220 grit wet/dry sandpaper.  It will set in about 3- 5 minutes.  If you need more time, you can refrigerate the Poly-Filler prior to use.  This will double the working time.  When completed, there will be a line at the joint.  This can be hidden using our MMA repair kit, which can be supplied in a color-matched coating.  The entire pedestal would need to be refinished to achieve a uniform color.  You will need to let us know the manufacturer of the lavatory, and their color name.  You will follow the directions shown in the MMA procedure, which is available in our website.

Thanks,

Rob Clos

To: Multi-Tech Products

I am the owner of a Bath Refinishing business. We currently specialize in refinishing bathtubs, showers, sinks, counter tops, etc. We have recently been asked by several plumbing supply companies to start offering bathtub spot repair and warranty work for their new bathtubs. There currently is no one offering this service within 100+ miles. While we can do an amateur job of color matching and feathering, we are not proficient at this type of work. Do you offer training or recommend a training company so that we can become proficient in this industry?

Please feel free to call or e-mail me. I am eager to discuss this with you.

Thank you,
Josh
To: Josh

We want to thank you for your interest in Multi-Tech Products for bath surface repair materials.
When people have experience in bathtub refinishing and use of our bathware repair materials, we find it is an easy transition from re-finisher to spot repair technician. The key is the right equipment, the right repair system, and the correct color for the brand of bathtub or spa being repaired. Although there are color variations in the industry, and within a manufacturer’s products, our colored systems can be finely adjusted by an operator with relative ease. Usually when ordering a specific color associated with a brand, it will be delivered to you very close to the manufacturer’s color standard and adjustments will be minimal. There are aspects to a specific product that can change color from the exact standard, which may cause the need to adjust color of the repair coating.  One example is color can change in acrylic-surfaced products as it is thermoformed into the tub shape.  Other potential color changes can occur due to the type of surface material, the unit age and technician ability.

Our Customer Service Department will help you to order the MTP recommended Starter Kit.  It will help you get acquainted with our spot repair materials. You should experiment with it on something like a scrapped bathtub that one of your retailers might have in stock. You should also practice using the proper air brush. The kit will include complete instructions, and will have a filler, color coating and a clear coat. It is our experience that most re-finishers use this kit as a first step in getting started performing spot repairs without a full training course. The most important tool for performing spot repairs is the correctly selected air brush with an adequate capacity (CFM) air compressor. We offer all of these tools.
We have two systems for surface repair materials:

1) MMA System which is utilized by manufacturers to achieve that perfect factory repair. (Polishing is required on the sprayed coating due to inherent factory air contamination)
2) Quick Glaze System which is normally chosen by repair professionals for field service. (a non-polished, quicker application because of less air contamination in homes)

Both systems use our Poly Filler and our coatings, which include a base color followed by a clear coat to protect the color from the environment. These coatings are applied with a single action, gravity fed airbrush.   I want to emphasize the importance of using the right airbrush, which is described and featured in our instructions. The other important consideration is the choice of the right type of mini compressor “tank type” with motor (1cfm) that delivers the optimum spray performance at 45 to 55 psi pressure for this specific style of airbrush and coatings.  If you make the wrong decisions regarding these critical factors, you will set yourself up for product performance problems such as  the coating being sprayed too “dry”, poor spray quality, or color and gloss matching.

The instructions will guide you to all the right tools. You will also find all recommended tools and accessories on our site.

Here are the links:
http://www.multitechproducts.com/categories/Quick-Glaze-System/
http://www.multitechproducts.com/categories/MMA-System/

Instructions:
http://www.acrylicfiberglass.com/Procedures/BATH%20REPAIR-Quick%20Glaze.pdf
http://www.acrylicfiberglass.com/Procedures/BATH-REPAIR-MMA.pdf

Tools on our site:
http://www.multitechproducts.com/electric-tools/
http://www.multitechproducts.com/paasche-h-airbrush-sets-extra-jars-longer-hose-options/

Please let our Customer Service Representative know what bath tub manufacturers supply your market area.
You may want to get that information from the supplier that is encouraging you to get into the repair business.
This will help you decide on initial color(s) and the correct repair system to order.
After becoming proficient in bath repair, I encourage you to expand your services to spa/hot tub repair. This can be very lucrative, since repair fees are generally higher. Procedures are similar, but you must use our Acrylic Filler rather than the Poly-Filler, since a spa surface is considered to be wet constantly.
Hope you find this helpful,
Rob Clos

Rob,

Thank you for the response. I look forward to using Multi-Tech surface repair products.
I am excited to test your Starter Kit and will be placing an order for the airbrush kit and supplies/products as soon as I have reviewed the options. Please don’t hesitate to call me if you have any questions.

Thank you,

Josh

TO:  Multi-Tech Products

I am trying to repair a hairline crack in a vitreous china (white Kohler K6652) service sink.  Which product would you recommend and what color white?
Thanks
Cindy
Cindy,

Unfortunately, a hairline fracture in vitreous china means there is a crack all the way through the fixture.  Vitreous china can be repaired and even glued back together with our colored Poly Paste product, and we have it in Kohler white.   However, the issue is how to get the Paste into the fracture.  Unless there are separated (broken)  pieces  than can be glued together, you would have to grind a “V” groove through the entire thickness of the sink.   Creating this “V’ groove would produce more damage to the surface than the original hair-line fracture, since it would be very visible.   Also, the back of the unit would need some kind of reinforcement to hold it together.  This procedure could be used if there is good access to the sink, but there are complications.

The repair would be complicated and require a refinish of the whole sink. The next question would be,  “should a service sink be completely refinished?”   The answer is no.  A service sink probably gets too much use and is exposed to damaging impacts, so a refinish would not last very long.  It could also be exposed to strong cleaning chemicals, which would cause the refinished surface coating to fail.

If it is sufficient to achieve a fix simply to prevent leakage through the crack, it could be repaired as described above. Be aware of the aesthetics limitations, and I would not give any kind of warranty.

Many things to think about. But, it is just wise to sometimes walk away from certain jobs. And sometimes, a technician needs to just make things functional too.

Hope this helps,

Rob

TO: Multi-Tech Products

I recently completed a cosmetic damage repair on a shower wall surround. I used my standard repair filler, color coating and methods. The repair failed as the filler fell out of the prepared area while the coating bonded well. I remember not recognizing the material but proceeded with my usual methods anyway. It was a small crack and the structure was solid. When I used my grinder to prepare the crack, I found a material with two or three layers. It had different colors to the layers. The thin bath ware top white color, a pure white plastic like layer, and the structural layer similar to a composite reinforced structure. The structure layer did not smell like fiberglass when I ground into it some. What do you think it was, and what is the proper way to repair it so it will hold?

Thanks,
Steve
Dear Steve;

It sounds like you found a product made from what is called “co-extruded” in the industry. This material is less expensive than traditional materials and is becoming more popular in economy products. You will find them at your local Home Centers. Manufacturers continually seek materials and processes to lower manufacturing costs. Historically, most bath tubs and shower products have been manufactured from cross-linked, cast acrylic sheet or gel coat. Both are reinforced with FRP (polyester resin with embedded glass fibers). Cast acrylic sheet is the most expensive acrylic on the market, and the cross-linked variety was specifically engineered for bathtubs and spas. Therefore, it has the best balance of physical and chemical properties for these applications.

The co-ex product you experienced is made by extruding a two-layer sheet – the top is a lower molecular weight, un-cross-linked acrylic, and the bottom is ABS (acrylonitrile-butadiene-styrene copolymer). Typically, the sheet is .125″ thick with the top layer being about .025″ and the bottom layer about .100″. When formed into bathtubs or shower walls, it can then be reinforced with FRP, polyurethane (PU), or have no reinforcement. PU may have glass fibers in the resin, and it can be a high density foam or a smooth coating. Sometimes it is reinforced with fiberboard strips or panels.

You mentioned there was an odor when grinding the structure. This is usually the best way to establish identity of a polyester resin. Simply use sand paper (320 grit) to sand the material in question before proceeding with a repair. Grinding may be required to expose the different layers. Polyester resins will have a distinct sweet smell with sanding or grinding friction. After the sanding test to confirm that it is a polyester, it is safe to use similar polyester resins for filling and reinforcement purposes. If there is no polyester odor, use our binding resin for reinforcement. It is formulated to adhere to PU and other plastic surfaces.

We would also recommend verifying the structural strength and integrity of the repair zone before applying the color coatings. Be certain there is no movement or stress to the area when hand pressure is applied. If there is, remove any filler and start over with the repair.

When repairing the cosmetic surface of bath products made with “co-ex” , our materials and processes work well. Our MMA or Quick Glaze systems perform very well as the color coating. In fact, since the lower molecular weight acrylic is not cross-linked, coatings adhere to it better. However, compared to polyester resins, it is more difficult to achieve adhesion on ABS or PU. So, you should not use Poly-Filler or any polyester resin based crack or putty fillers. The deceiving factor is that most polyester fillers will initially bond to the material for a short period.   However, after time it will lose its adhesion to the ABS or PU, and will break away from the repair zone. Our acrylic filler should be used for this application.

I hope this provides you the necessary information to perform the best repair.  If you need more help, please call or email.

Thanks,

Rob Clos

To:  Multi-Tech Products

I am a new surface repair tech, and I am having difficulty getting a good cured repair on gel coat bathtub repairs. The surface remains tacky too long, and doesn’t achieve a satisfactory hardness. What am I doing wrong?
Thanks,
Richard
Richard,

The most common problem repair technicians have is “a tacky surface” after the sprayed gel coat has completed its heat cycle. The easy explanation is they have attempted to use a short cut in the application.
Many repair pros try to spray gel coat through a Preval® sprayer, since it is easy and convenient. This sprayer is an aerosol set up that allows mixing the ingredients in a glass jar. It is then atomized at low pressure using an aerosol source.
The low pressure requires the gel goat to be thinned excessively for spraying. This results in creating a recipe outside of the manufacturer’s requirements for optimum performance. Technicians have reported to us they try to use acetone as a thinner and create a 50% mixture. Every gel coat chemist says “do not thin gel goat more than 10-15% and use styrene only”

Gel coat is made for production factories “ready to spray” at 60-80 psi at the gun. Catalyzing at the gun tip yields optimum chemistry in this setting. The mold keeps oxygen away from the surface and gives the maximum hardness to the sprayed gel coat surface. When cured gel coat is pulled from the mold’s surface, there is absolutely no tackiness.

To duplicate this result in a repair application and achieve a tack free finish, you must:
-Spray pure gel coat at the recommended pressure (50-60psi). This requires an air compressor and proper spray gun or air brush.
-Spray it as close to the original manufacturer’s formula as possible (thin no more the 10-15%)
-Catalyze to between 1 to 3% with 90% MEKP
-Thin only with styrene.
-Most importantly, seal the surface at “peak exothermic cycle” with PVA.

All materials and tools are available from us. Using the proper materials and equipment will yield a more professional result, and a happier customer.

For more information on proper application of gel coat go to:

http://www.multitechproducts.com/content/Procedures/GELCOAT%20REPAIR%20GUIDELINE%20NCINSTGCGD-v%202.pdf

Ken Wolfe
Consulting Chemical Engineer
Multi-Tech Products Corp.

TO:  Multi-Tech Products

I am repair technician and I can never achieve a hidden repair with your MMA system on acrylic.
My filler and contour application is perfect, but I always have a dark ring effect around the repair area after buffing.
I know factories use this product to get perfect repairs. What do they do differently? One factory even sends me the color. So I know it is the right color.
What am I doing wrong?  See photo.

John

Repair Technician

photo

 

 

 

 

 

 

Hello John,

This is one of the most common questions from repair technicians about achieving the perfect repair with our MMA System on acrylic bath and shower repairs.   The simple answer is the Clear Coat must be used.  Many technicians don’t understand the functions and importance of the clear coat, and therefore they think it is not necessary.

Some bath ware manufacturers send  only the product color coating (base coat) to technicians for warranty repairs. This certainly helps the contracted technician to use the proper color, but it might give the impression that only the base coat is needed for the repair.  I would also believe the customer service representative may not understand all of the requirements, as well.  However, the clear coat plays a role in both the dark ring, and the endurance of the repair.  The dark ring you mention develops when the base coat is sanded and polished without the presence of Clear Coat.

Since the MMA Basecoat is highly pigmented, it is not designed to withstand dirt, soap and general bath and shower environment usage.  Over a short period of time, the repair zone without Clear Coat will change color and become stained.  The Clear Coat is formulated to seal the base coat and give the repair its hardness, UV protection, and longevity.

How to remove the dark line?

With a good color match to the surface, the dark line will disappear when the Base coat color is sprayed on to the surface. This is done by  blending (feathering) the outer ring of the color application with the airbrush and spray process.  The dark ring appears, again, when the base coat is sanded. The sanding process  removes the hiding ability of the blend-out of the spray.  The clear coat, applied over the sanded base coat, can not remove the dark line. The clear coat must be sprayed over a “blended and without being sanded base coat”.  This will seal the feathered affect, and hide the dark line. Then the clear coat is sanded and polished. But the clear coat cannot be sanded excessively to remove the coatings, entirely.  The clear coat will then protect the colored base coat, and leave the blended area undisturbed.

Typically, this does not happen with gel coat repairs. Why does it happen on acrylic repairs?

Acrylic is a translucent material composed of a clear polymer with pigments added to achieve the desired color.  When compared to acrylic, gel coat is a resin with a higher loading of pigment.  Acrylic products are made by vacuum forming a flat sheet, heated to a high temperature, into the desired shape.  A highly loaded acrylic resin would be more brittle, and less able to be thermoformed.  Whereas, gel coat is sprayed onto a mold surface, so it can be highly loaded with pigment as long as it can be sprayed.  Higher-priced products are made from acrylic, since it is superior in properties needed for bath ware and spas compared to gelcoat resin.  When repairing a surface, a coating is used to match the color of the product.  It is sprayed over the repair filler and it’s adjacent area.  When the coating is applied to an acrylic surface, it creates a shadow at sharp, delineated edges of the coating. This is due to the thickness and transparency of the acrylic.  Even with a good repair base coat color match,  a dark halo is cast around the repair when sanded.  The only way to address the shadow casting effect, is to blend(feather) the base coat color, and apply (spray) a clear coat over it for protection and to preserve the appearance.

How to “blend” or “feather” the MMA base coat?

A single action (important) air brush operating at 35 psi (1 cfm air source) at the gun is required.  First, spray the base coat sufficiently to cover the filler area. This may take several layers (see MMA instructions).  Then open up the airbrush spray pattern to allow a higher volume of product to be sprayed. Using the correct temperature thinners and a smooth spray-out from the gun, pull the gun away (6-8 inches) from the spray surface, and feather coat the base coat around the edges of the previous sprayed area. Try to achieve a smooth surface that hides the edges of the over-spray.  If the product has sprayed a little dry and the surface around the area looks dull, wet-out those areas with straight MMA Finishing solvent from the gun in a clean separate jar. Do not over flood the area. Allow the coating and Finishing solvent to evaporate  (dry) before clear coating. This is the procedure required to create undetectable repairs on surfaces.  This spot repair technique also works with our Quick Glaze Systems.

Here is a summary of the important reasons to use Clear Coat over MMA Basecoats:

-Clear Coat seals the base coat color to retain its match and blend (feather effect) during the sanding and buffing process.
-Clear Coat is imperative for gloss and wear protection.
-Clear Coat adds depth to the acrylic look and effect matching the original surface.
-Clear Coat seals the color coat so it will not absorb detergents, dirt and elements from hard water.(most important) -Clear Coat is a necessary system component formulated and designed to be used with every MMA Basecoat application.

Other important MMA System components and tips are:

-The proper airbrush (Single action) 35 psi at the gun with a 1 cfm air source. Very important.
-Use MMA System Thinners, only. Alternative thinners will effect spray performance and final color.
-Use proper rated temperature thinners for ambient working conditions. The wrong thinner selection can cause dry spray out.
-Note: MMA Basecoats will darken as they dry. Decide on color adjustments after it dries.  Light forced heating is okay.
-Sanding can be performed on base coats, but reapply the base coat and perform the feathering prior to Clear Coating.

Here is a link to the MMA System repair instructions.

http://www.acrylicfiberglass.com/Procedures/BATH-REPAIR-MMA.pdf

Rob Clos

President

 

Dear Multi-Tech Products;

I have a crack in the radius at the bottom of an acrylic bathtub.  Must I contract someone to install an inlay to replace the entire bottom of the bath, or is their an acceptable, easier way to fix it?  See the photo.

Thanks,

Roger

photo 2 photo 1

To: Roger

The use of an inlay to repair cracks in the bottom of a bathtub is always the safest way to prevent re-occurrence.   However, after saying that, there can be some latitude in recommended repair techniques depending on the severity and exact location of the crack(s).  I would say that your example, where the one crack is located right at the radius does not require an inlay.  If the crack extended into the flat area, it would need a more stealthy repair offered by inlays.

Your crack, most likely, occurred due to either insufficient support under the base, or movement in the tub.  In sufficient support allows the tub bottom to flex under weight.  This repeated flexing eventually results in crack formation.  Therefore, my first recommendation is to add structural support by injecting our 5-lb. density polyurethane foam into the base cavity to restrict movement.  It does not increase basic structural strength, but it is effective in reducing movement.  If additional structure strength is necessary, it will need to be added using fiberglass resin over the top of the weak area.  The combination of these two processes will provide the permanent repair desired.

You can refer to the blog entry, FIXING A SQUEAKY, FLEXING BATHTUB OR SHOWER, for a description of how to add polyurethane foam.  Your small crack area can be fixed using a glass fiber stitch mat with our Binding resin.  The stitch mat should be cut to a size that completely covers the crack, and extends about 3 inches beyond it.  Refer to http://www.multitechproducts.com/content/Procedures/Binding-Resin-Spa-Blister-Repair-2010.pdf for instructions on laying down stitch mat.  Obviously, this means the repair zone will be raised in relation to the normal surface.  So you should use our Poly-Filler or Poly-Paste to buildup and transition smoothly to the existing surfaces.   Since this area is at the edge of the tub bottom, it will not effect water drainage.

Roger, theoretically,  any crack on a bathtub bottom could be repaired in this manner.  However, based on the size and exact location, it could significantly diminish the ability of the tub to drain, properly.  Your case is simple, and these procedures should result in a very satisfactory repair.  Crack size and location are the determining factors whether to resort to an inlay repair.  Inlays also offer the ability for a technician to offer the optimum warranty for a repair.

After these procedures are completed, the color needs to be restored to match the other surfaces.  Refer to the procedures on bathtub crack repair for directions on preparing the surface and spraying a colored coating over the repair.  You may also choose to use our color-matched repair paste.   In cases that the bathtub has a textured surface, the surface can be duplicated using the texture additive materials described in repairing granite spas.  However, you may decide that it is acceptable to leave a small smooth area at the repair, if it is not noticeable.

I hope this information helps you to resolve your problem.  Please call if you have further questions.

Regards,

Rob Clos

TO: Multi-Tech Products:

I am a repair technician; I have inspected a cultured marble whirlpool with a 4″ vertical crack on the tub. The crack is on the bottom radius around 12″ from the drain. The tub has leaked through due to the crack.  Do you have a method/product that we can use to repair cultured marble and guarantee that the tub would no longer leak.

Any help you can give us would be greatly appreciated.  We look forward to hearing back from you.  If you have any questions, please don’t hesitate to contact us. Otherwise, have a wonderful day.

All the best,
Maureen

TO: Maureen

You describe a thermal stress crack created by the shock of hot and cold water.  I have seen this type of crack go completely around the perimeter of the tub.

In order to repair it, and prevent future propagation of the same crack, you need to drill a hole at each end of the visible crack.  Be sure to drill through the entire depth of the tub with a ¼ drill.   Then grind a deep slot into the structure along the entire length of the crack. Just grinding an 1/8th inch groove in the top surface is insufficient since it will continue to crack. This is because the crack goes through the complete structure. The surface will continue to expand and contract as it is exposed to hot and cold water. This expansion and contraction will lead to a new crack directly through the repair. Cultured marble bathtubs aren’t reinforced with glass fibers, so they have less strength to resist failure from expansion cracks.   If there is access to the back of the bathtub, you should attempt to add reinforcement using fiberglass mat.  The combination of reinforcement on the back side and grinding the crack open through the structure will provide the best permanent repair.

The fact that this is a relatively short crack improves the probability that this crack can be satisfactorily fixed.

If there is no way to get glass on the backside, aggressive grinding and heavy glass reinforcement from the top side will achieve a good repair. The repair procedure should be:

  1. Grind the crack to create a recess in the top surface along the crack wide enough ( probably 2 to 3 inches) to accommodate the fiberglass mat.
  2. Using a heavy duty die grinder, grind a slot channel that would hold a recessed layer of heavy duty stitch mat. The stitch mat would be about an 1/8th of inch thick. A slot grove would need to be ground ¼ inch deep to hold the mat and the resin while leaving enough room for the poly filler after the mat and resin application. The slot groove would not go through the structure, but leave enough structure to bond to. The slot groove would hold the width of the Stitch mat to straddle the crack a little over an inch on each side of the crack. If the crack is 1/16th inch by 12 inches. The slot groove should straddle the crack by 1 ¼ on each side and extend past the end of the crack the same. Total groove over the crack 2 ½ inches x 14 ½ inch long by ¼ deep.
  3. With the groove and the crack prepared to except the fiberglass application, apply catalyzed Iso resin to the glass first and place it in the groove.  Smooth out and remove bubbles.
  4. Force cure with a heat gun.
  5. Fill with Poly-filler.
  6. Use our Quick Glaze system with the Clear Coat to achieve better color match and appearance.

You should charge your customer between $350 to $450 for this best-practice job, and it should take 3-4 hours to complete.

Hope this helps.

Rob Clos

Dear Multi-Tech,

Hello,  I have a question about your acrylic filler and granite materials.. One, should the clear coat be white in color,  it looks cloudy, not clear. Two, everything for the repairs pastes are different in consistency from body fillers for spreading and shaping. Third, the product is very hard when cured making it harder to sand. Is this how it’s supposed to be? It doesn’t seem correct to me being a body repair tech for 25 years, clear is never cloudy and this filler repair when cured is hard as nails and not easy to sand?

Max

Hello Max,

The cloudiness of the clear is correct for the product. It is rich in resin bringing a high solids content to the product. However, this will not cause it to be visible on the surface of the repair.

Everything else you describe is normal. The hardness of the end product will provide a higher quality repair with greater endurance in the spa and bath surface repair applications.

Your comments about the consistency of the acrylic resins are normal opinions from an auto body person’s experience base.

Most auto body products are developed for ease of workability, while giving good performance in the relatively dry environment that vehicle surfaces must endure.

Body filler, spot putty’s, primers and automotive coatings (having ease of use) will all absorb water and fail, especially when used for a bath tub or spa surface repair.

photo 1

 

 

 

 

 

 

 

The picture shows how auto body fillers fail when used for bath or spa repairs.

Since bath tub and hot tub environments are wet environments (water, heat and chemicals), they require resins which contain high levels of special additives to prevent moisture absorption, so they will provide the expected durability and performance.

Thus, the completed repair is much harder than in auto body repair materials.

At the same time, these special additives impart color and translucency to the initial clear resin.

The chemistry of these additives are designed to be compatible with the base resin and provide the desired properties for superior performance.  Unfortunately, this means they may be more difficult to work with.  A hard surface in a bathtub or spa repair results in better performance.

A good rule of thumb; if the product sands, shapes and works easily (softer), it will absorb water and deteriorate in a very wet environment.  Auto body pastes and epoxies fall in this category.

Even though these plastic products may be more difficult to work with, they have been designed for the purpose. These issues are minimized with the use of proper tools.

Aggressive grinding and shaping will require applying the filler in multiple layers. To fill voids, skim coat applications, using the same filler, will provide maximum performance in the finished repair.

Your comments and observations are expected. We have many repair techs from the auto body industry using our products.  Understand there will be a learning curve while adjusting application and working techniques when transferring to Multi-Tech surface repair products.

I hope this helps, and good luck with your repairs.

Rob Clos